National Beef Quality Audit-2022 Phase 1: face-to-face and digital interviews

The National Beef Quality Audit (NBQA) has been conducted regularly since 1991 to assess and benchmark quality in the U.S. beef industry, with the most recent iteration conducted in 2022. The goal of NBQA Phase I is to evaluate what needs to be managed to improve beef quality and demand. Interviews (n = 130) of industry personnel were conducted with the aid of routing software. In total, packers (n = 24), retailers (n = 20), further processors (n = 26), foodservice (n = 18), and allied government agencies and trade organizations (n = 42) were interviewed. Interviews were routed in software based on interviewee involvement in either the fed steer and heifer market cow and bull sectors, or both. Interviews were structured to elicit random responses in the order of determining "must-have" criteria (quality factors that are required to make a purchase), best/worst ranking (of quality factors based on importance), how interviewees defined quality terms, a strength, weakness, opportunities, threats (SWOT) analysis, general beef industry questions, and sustainability goals (the latter four being open-ended). Quality factors were 1) visual characteristics, 2) cattle genetics, 3) food safety, 4) eating satisfaction, 5) animal well-being, 6) weight and size, and 7) lean, fat, and bone. Best/worst analysis revealed that "food safety" was the most (P < 0.05) important factor in beef purchasing decisions for all market sectors and frequently was described as "everything" and "a way of business." Culture surrounding food safety changed compared to previous NBQAs with interviewees no longer considering food safety as a purchasing criterion, but rather as a market expectation. The SWOT analysis indicated that "eating quality of U.S. beef" was the greatest strength, and cited that educating both consumers and producers on beef production would benefit the industry. Irrespective of whether companies' products were fed or market cow/bull beef, respondents said that they believed "environmental concerns" were among the major threats to the industry. Perceived image of the beef industry in the market sectors has improved since NBQA-2016 for both fed cattle and market cow/bull beef.

National Beef Quality Audit-2022: Transportation, mobility, live cattle, and hide assessments to determine producer-related defects that affect animal welfare and the value of market cows and bulls at processing facilities

The National Beef Quality Audit (NBQA)-2022 serves as a benchmark of the current market cow and bull sectors of the U.S. beef industry and allows comparison to previous audits as a method of monitoring industry progress. From September 2021 through May 2022, livestock trailers (n = 125), live animals (n = 5,430), and post-slaughter hide-on animals (n = 6,674) were surveyed at 20 commercial beef processing facilities across the U.S. Cattle were transported in a variety of trailer types for an average distance of 490.6 km and a mean transport time of 6.3 h. During transit, cattle averaged 2.3 m2 of trailer space per animal indicating sufficient space was provided according to industry guidelines. Of all trailers surveyed, 55.3% transported cattle from an auction barn to a processing facility. When surveyed, 63.6% of all truck drivers reported to be Beef Quality Assurance certified. The majority (77.0%) of cattle were sound when evaluated for mobility. Mean body condition scores (9-point scale) for beef cows and bulls were 3.8 and 4.4, respectively, whereas mean body condition scores (5-point scale) for dairy cows and bulls were 2.3 and 2.6, respectively. Of the cattle surveyed, 45.1% had no visible live animal defects, and 37.9% had only a single defect. Of defects present in cows, 64.6% were attributed to an udder problem. Full udders were observed in 47.5% of all cows. Nearly all cattle were free of visible abscesses and knots (97.9% and 98.2%, respectively). No horns were observed in 89.4% of all cattle surveyed. Beef cattle were predominantly black-hided (68.9% and 67.4% of cows and bulls, respectively). Holstein was the predominant dairy animal observed and accounted for 85.7% of the cows and 98.0% of the bulls. Only 3.1% of all animals had no form of identification. Findings from the NBQA-2022 show improvements within the industry and identify areas that require continued education and research to improve market cow and bull welfare and beef quality.

Palatability Assessments of Beef Top Loin Steaks Sourced from Three Quality Grade/Brand Categories from Texas and Non-Texas Processing Establishments

Beef top loin steaks from Top Choice (Modest and Moderate marbling), Choice (primarily Small marbling), and Select (Slight marbling) beef strip loins from Texas and Non-Texas (Kansas, Nebraska, and Colorado) beef processing establishments were obtained to determine the role of source and USDA grade/brand category on consumer sensory panel and Warner-Bratzler shear (WBS) evaluations. The number of strip loins obtained were 58 Texas Top Choice, 54 Texas Choice, and 56 Texas Select and 60 Non-Texas Top Choice, 52 Non-Texas Choice, and 58 Non-Texas Select. There were source × USDA grade/brand category interactions for overall liking (P = 0.012) and tenderness liking (P = 0.002) in which the Texas Top Choice steaks received ratings that did not differ (P &gt; 0.05) from Texas Select steaks but did differ (P &lt; 0.05) from the Non-Texas Top Choice steaks. There were no (P = 0.079) differences in WBS values for steaks from the 2 sources even though the P value approached significance. For USDA quality grade/brand category, there were differences (P &lt; 0.001) in WBS values, but not in the direction one might expect: Choice steaks had the lowest (P &lt; 0.05) WBS values compared with those from Top Choice and Select steaks, which did not differ (P &gt; 0.05) from each other. Percentage dis- tribution of WBS values according to tenderness categories showed that all of the Top Choice and Choice steaks, regardless of source, had values that met the threshold values for Very Tender (WBS &lt; 31.4 N) or Tender (31.4 N &lt; WBS &lt; 38.3 N). While geographic purchasing biases may remain, these data assist in supporting informed decisions regarding palatability and consumer acceptability as functions of beef sourcing.

Palatability assessments of beef strip loin steaks portioned by weight or by thickness sourced from various carcass weight/ribeye area size combinations

Beef carcasses (n = 90; U.S. Choice) met a 3 ribeye area (REA - Small, Medium, Large) × 3 carcass weight (CW - Light, Intermediate, Heavy) scheme to assess palatability on steaks cut by portion thickness (PT- 3.18 cm) and weight (PW -340 g). Significant interactions revealed trends for steaks from the Small REA, regardless of CW, to have among the lowest shear-force values. For PT steaks, significant interaction for overall liking revealed no differences for Small and Medium REA across all CW categories, but steaks from Large REA from Light CW differed (P < 0.05) from the other two CW categories. For PT steaks, overall liking and tenderness liking scores were higher (P < 0.05) for Small REA compared to other categories, whereas CW did not influence any palatability trait. REA and CW do impact beef steak palatability, though steaks from all combinations were "very tender" and highly acceptable from a palatability standpoint.

Sorting beef subprimals by ribeye area size at the packer level to optimize utility and product uniformity in foodservice and retail

The objectives of the study were to evaluate if sorting beef carcasses at the packer level by loin muscle (LM) area, using instrument grading technology, would increase the consistency of three boxed beef products for the foodservice and retail sectors of the industry. U.S. Department of Agriculture (USDA) Choice beef sides (n = 100) and USDA Select sides (n = 100) were selected and stratified into five LM area categories (±2.9 cm²): 1) 77.4, 2) 83.9, 3) 90.3, 4) 96.8, and 5) 103.2 cm². Beef lip-on ribeyes and boneless strip loins were obtained from USDA Choice sides and full, partially defatted tenderloins were obtained from USDA Select sides. Subprimals were scanned with a portioner that captured visual images and dimensional analyses of each subprimal, and data were analyzed by the software to determine multiple portioning outcomes for each subprimal. Portioning data were generated for each subprimal based on a variety of targeted portion weights (ribeye and strip loin steaks = 340.2 g; tenderloin steak = 170.1 g), as well as various portion thicknesses (ribeye and strip loin steaks = 31.8 mm; tenderloin steak = 44.5 and 50.8 mm). Subprimal utility varied across targeted portion weights and thicknesses within each LM area category. For the ribeyes and strip loins, optimal portion weight and thickness combinations were observed more frequently in LM area categories 1 and 2 than for the three larger LM area categories. Analysis of data for tenderloins revealed that LM area categories played a lesser role in identifying optimization of steak portion weight and thickness combinations. Findings demonstrate that creating categories of beef subprimals based on LM area as opposed to subprimal weight might provide a unique sorting method that would improve boxed beef product consistency and uniformity for foodservice and retail sectors.

Assessment of Salmonella Prevalence in Lymph Nodes of U.S. and Mexican Cattle Presented for Slaughter in Texas

Foodborne salmonellosis has been traced to undercooked ground beef and other beef products in the past, and peripheral lymph node (LN) presence in the fatty tissues of beef carcasses is one possible source of Salmonella contamination. Researchers have previously reported higher rates of Salmonella prevalence in LNs from cattle raised and harvested in Mexico compared with rates typically observed from cattle harvested in the United States. With cattle of Mexican origin comprising the majority of U.S. live cattle imports, the objectives of this study were designed to determine whether Salmonella prevalence in LNs differed (i) between cattle of Mexican and U.S. origins when exposed to the same South Texas feeding operation and (ii) between warm and cool seasons. To meet these objectives, paired (left and right sides) subiliac LNs ( n = 800 LNs; n = 400 pooled samples) were collected from 100 carcasses per origin (Mexico and United States) per season (cool, December to January; warm, July to September). Overall, Salmonella prevalence in LN samples was 52.0% (208 of 400). No difference ( P = 0.4836) was seen in Salmonella prevalence as a function of origin, with 54.0% (108 of 200) and 50.0% (100 of 200) of LN samples returning Salmonella-positive results from cattle of Mexican and U.S. origin, respectively. Salmonella prevalence differed ( P = 0.0354) between seasons, with 46.5% (93 of 200) of cool and 57.5% (115 of 200) of warm season samples returning Salmonella-positive results. Serotyping of PCR-confirmed positive samples resulted in 14 different serovars being identified, with Cerro (21.6%), Anatum (19.7%), Muenchen (17.8%), Montevideo (14.4%), and Kentucky (12.0%) comprising the majority of serovars. These results suggest that factors other than cattle origin may be impacting Salmonella prevalence rates in bovine LNs and that additional research is needed to better understand the role of environment and management-related factors on Salmonella prevalence in bovine LNs.

Consumer and Warner-Bratzler Shear Evaluations of Steaks from Blade Tenderized, Aged, or Frozen Sirloin Subprimals

Paired USDA Choice top sirloin butts (n = 60) were divided equally across 3 trials: 1) blade tenderized (BT) versus non-blade tenderized (NBT), 2) refrigerated versus frozen aging/storage, and 3) 14-d versus 35-d refrigerated aging. Steaks from subprimals were evaluated using Warner-Bratzler Shear (WBS) force testing and consumer sensory evaluation. Consumers found BT steaks to be more tender and palatable compared to NBT steaks (P < 0.05), even though WBS values did not differ. Steaks from refrigerated versus frozen and 14- versus 35-d age treatments did not differ (P > 0.05) in consumer sensory ratings or WBS values. When compared to refrigerated, frozen storage of product did not affect consumer sensory ratings. Lack of differences between 14- and 35-d aging treatments indicated that the top sirloin butt did not require extended-aging periods to increase tenderness. Blade tenderization remains important for the top sirloin; however, purveyors may have options in postmortem aging and frozen storage of product without sacrificing quality.

National survey of Salmonella prevalence in lymph nodes of sows and market hogs

Livestock are known to harbor Salmonella in their gastrointestinal (GI) tract and lymphatic tissues. Pathogens may be transferred from the GI tract to external carcass surfaces during normal harvest procedures but can be mitigated by antimicrobial carcass interventions. Lymph nodes (LNs) are typically encased in fat and are protected from antimicrobial carcass surface treatments, thus serving as a possible root cause of foodborne illnesses attributed to Salmonella in meat products. Members of the pork industry are committed to food safety and want to better understand Salmonella as a potential contaminant in pork products. To establish a baseline of Salmonella prevalence in porcine LNs across the United States, 21 commercial pork harvest facilities, representing northern (n = 12) or southern (n = 9) geographical regions, participated in this study. As processing volumes allowed, 25 carcasses were selected from each establishment. From each carcass, left and right superficial inguinal LNs (n =1,014 LNs) were removed and pooled to yield one sample per animal or n = 507 total LN samples. Salmonella prevalence rates differed (P < 0.05) between hog types in both regions. Specifically, 6.4% of market hog and 37.0% of sow samples were Salmonella positive in the northern region. This was reversed in the southern region as 13.0% of market hog and 4.8% of sow samples were Salmonella positive. There also was a difference (P < 0.05) in prevalence rates between northern and southern regions for sows, but not market hogs (P > 0.05). Type of chilling method (conventional, blast, or other) used at each market hog facility (n = 12) was documented. In the northern region, prevalence rates of Salmonella across chilling types were as follows: 20.0%, 2.7%, and 1.3% positive samples for conventional, other, and blast chill methods, respectively. In the southern region, 20.0% of samples were positive for conventional, 0.0% for blast, and 12.0% for other chilling methods. In both regions, samples from conventionally chilled carcasses returned more (P < 0.05) positive results than any other chill method. Overall, the higher rate of Salmonella prevalence in northern sows warrants further investigation, and members of the pork industry would benefit from the identification of possible methods to address the presence of Salmonella in porcine LNs.

Comparison of Salmonella Prevalence Rates in Bovine Lymph Nodes across Feeding Stages

Peripheral lymph nodes (LNs) located in the fatty tissues of beef carcasses have been shown to harbor Salmonella and, thus, potentially contaminate ground beef. Salmonella prevalence within LNs is known to differ among feedlots. Two South Texas feeding operations (identified as locations A and B) known to harbor salmonellae in the feedlot environment, while historically producing cattle with opposing rates (one "high" and one "low") of Salmonella prevalence in LNs, were used in this study. To determine whether this difference was due to cattle source or factors associated with different stages of feeding, weanling steers of common and known origin were followed through normal feeding stages at both operations. Eighty Angus-sired beef steers were harvested at each of four feeding stages: 1, postweaning; 2, background or stocker; 3, 60 days on feed; and 4, 120 days on feed. Left and right subiliac and superficial cervical LNs ( n = 304) were collected from each carcass, and similar node types were pooled by animal ( n = 152). Results showed a difference ( P < 0.05) in prevalence of Salmonella in bovine lymph nodes between location A and location B and among feeding stages in location B. Salmonella was not isolated from any feeding stage 1 (postweaning) or location A LN samples. Within location B, there was an increase in Salmonella prevalence as cattle moved into later stages of feeding: at 22.2% (4 of 18), 77.8% (14 of 18), and 94.4% (17 of 18) for feeding stages 2, 3, and 4, respectively. Although the reasons for the differences seen between feeding operations and for increased Salmonella prevalence in LNs at later feeding stages remain unexplained, these results indicate that factors other than cattle source are likely influencing Salmonella prevalence in LNs.

National Beef Quality Audit-2016: assessment of cattle hide characteristics, offal condemnations, and carcass traits to determine the quality status of the market cow and bull beef industry

To continue the series that began in 1994, the National Beef Quality Audit (NBQA) – 2016 was conducted to quantify the quality status of the market cow and bull beef sector, as well as determine improvements made in the beef and dairy industry since 2007. The NBQA-2016 was conducted from March through December of 2016, and assessed hide-on carcasses (n = 5,278), chilled carcasses (n = 4,285), heads (n = 5,720), and offal items (n = 4,800) in 18 commercial processing facilities throughout the United States. Beef cattle were predominantly black-hided; 68.0% of beef cows and 67.2% of beef bulls possessed a black hide. Holstein was the predominant type of dairy animal observed. Just over half (56.0%) of the cattle surveyed had no mud contamination on the hide, and when mud was present, 34.1% of cattle only had small amounts. Harvest floor assessments found 44.6% of livers, 23.1% of lungs, 22.3% of hearts, 20.0% of viscera, 8.2% of heads, and 5.9% of tongues were condemned. Liver condemnations were most frequently due to abscess presence. In contrast, contamination was the primary reason for condemnation of all other offal items. Of the cow carcasses surveyed, 17.4% carried a fetus at the time of harvest. As expected, mean carcass weight and loin muscle area values observed for bulls were heavier and larger than cows. The marbling scores represented by cull animal carcasses were most frequently slight and traces amounts. Cow carcasses manifested a greater amount of marbling on average than bull carcasses. The predominant fat color score showed all carcasses surveyed had some level of yellow fat. Only 1.3% of carcasses exhibited signs of arthritic joints. Results of the NBQA-2016 indicate there are areas in which the beef and dairy industries have improved and areas that still need attention to prevent value loss in market cows and bulls.

National Beef Quality Audit - 2016: Survey of carcass characteristics through instrument grading assessments

The instrument grading assessment portion of the National Beef Quality Audit (NBQA) - 2016 allows the unique opportunity to evaluate beef carcass traits over the course of a year. One week of instrument grading data was collected each month from 5 beef processing corporations encompassing 18 facilities from January 2016 through December 2016 ( = 4,544,635 carcasses). Mean USDA yield grade (YG) was 3.1 with 1.37 cm fat thickness (FT), 88.9 cm LM area, 393.6 kg HCW, and 2.1% KPH. Frequency distribution of USDA YG was 9.5% YG 1, 34.6% YG 2, 38.8% YG 3, 14.6% YG 4, and 2.5% YG 5. Increases in HCW and FT since the NBQA-2011 were major contributors to differences in mean YG and the (numerically) increased frequency of YG 3, 4, and 5 carcasses found in the current audit. Mean marbling score was Small, and the distribution of USDA quality grades was 4.2% Prime, 71.4% Choice, 21.7% Select, and 2.7% other. Frequency of carcasses grading Prime on Monday (6.43%) was numerically higher than the average frequency of carcasses grading Prime overall (4.2%). Monthly HCW means were 397.6 kg in January, 397.2 kg in February, 396.5 kg in March, 389.3 kg in April, 384.8 kg in May, 385.0 kg in June, 386.1 kg in July, 394.1 kg in August, 399.1 kg in September, 403.9 kg in October, 406.5 kg in November, and 401.9 kg in December. Monthly mean marbling scores were Small in January, Small in February, Small in March, Small in April, Small in May, Small in June, Small in July, Small in August, Small in September, Small in October, Small in November, and Small in December. Both mean HCW and mean marbling score declined in the months of May and June. The month with the greatest numerical frequency of dark cutters was October (0.74%). Comparison of overall data from in-plant carcass and instrument grading assessments revealed close alignment of information, especially for YG (3.1 for in-plant assessment versus 3.1 for instrument grading) and marbling (Small for in-plant assessment versus Small for instrument grading). These findings allow the beef industry access to the greatest volume of beef value-determining characteristics for the U.S. fed steer and heifer population than ever reported, resulting in potentially more precise targeting of future quality and consistency efforts.

National Beef Quality Audit-2016: In-plant survey of carcass characteristics related to quality, quantity, and value of fed steers and heifers

The National Beef Quality Audit (NBQA)-2016 used in-plant cooler assessments to benchmark the current status of the fed steer and heifer beef industry in the United States. In-plant cooler assessments ( = 9,106 carcasses) were conducted at 30 facilities, where approximately 10% of a single day's production were evaluated for USDA quality grade (QG) and yield grade (YG) factors. Frequencies of evaluated traits were 66.5% steer and 33.4% heifer sex classes and 82.9% native, 15.9% dairy-type, and 1.2% estimated breed types. Mean USDA YG factors were 1.42 cm for adjusted fat thickness, 89.5 cm for LM area, 390.3 kg for HCW, and 1.9% for KPH. Mean USDA YG was 3.1, with a frequency distribution of 9.6% YG 1, 36.7% YG 2, 39.2% YG 3, 12.0% YG 4, and 2.5% YG 5. Mean USDA QG traits were Small for marbling score, A for overall maturity, A55 for lean maturity, and A for skeletal maturity. Mean USDA QG was Select with a frequency distribution of QG of 3.8% Prime, 67.3% Choice, 23.2% Select, and 5.6% lower score. Lower score included dark cutter (1.9%), blood splash (0.1%), and hard bone, which are USDA overall maturity scores of C or older (1.8%). Marbling score distributions were 0.85% Slightly Abundant or greater, 7.63% Moderate, 23.54% Modest, 39.63% Small, 23.62% Slight, and 0.83% Traces or less. Carcasses that were Choice or Select and USDA YG 2 or 3 accounted for 70.7% of the carcasses evaluated. Compared with the previous NBQA, we found a numerical increase in mean USDA YG, USDA QG, adjusted fat thickness, HCW, LM area, and marbling score with an increase in dairy-type carcasses and percentage of carcasses grading USDA Prime and Choice as well as frequency of USDA YG 4 and 5. The findings from this study will be used by all segments of the industry to understand and improve the quality of fed steer and heifer beef that is being produced.

National Beef Quality Audit-2016: Transportation, mobility, live cattle, and carcass assessments of targeted producer-related characteristics that affect value of market cows and bulls, their carcasses, and associated by-products

The National Beef Quality Audit–2016 marks the fourth iteration in a series assessing the quality of live beef and dairy cows and bulls and their carcass counterparts. The objective was to determine the incidence of producer-related defects, and report cattle and carcass traits associated with producer management. Conducted from March through December of 2016, trailers (n = 154), live animals (n = 5,470), hide-on carcasses (n = 5,278), and hide-off hot carcasses (n = 5,510) were surveyed in 18 commercial packing facilities throughout the United States. Cattle were allowed 2.3 m² of trailer space on average during transit indicating some haulers are adhering to industry handling guidelines for trailer space requirements. Of the mixed gender loads arriving at processing facilities, cows and bulls were not segregated on 64.4% of the trailers surveyed. When assessed for mobility, the greatest majority of cattle surveyed were sound. Since the inception of the quality audit series, beef cows have shown substantial improvements in muscle. Today over 90.0% of dairy cows are too light muscled. The mean body condition score for beef animals was 4.7 and for dairy cows and bulls was 2.6 and 3.3, respectively. Dairy cattle were lighter muscled, yet fatter than the dairy cattle surveyed in 2007. Of cattle surveyed, most did not have horns, nor any visible live animal defects. Unbranded hides were observed on 77.3% of cattle. Carcass bruising was seen on 64.1% of cow carcasses and 42.9% of bull carcasses. However, over half of all bruises were identified to only be minor in severity. Nearly all cattle (98.4%) were free of visible injection-site lesions. Current results suggest improvements have been made in cattle and meat quality in the cow and bull sector. Furthermore, the results provide guidance for continued educational and research efforts for improving market cow and bull beef quality.

National Beef Quality Audit-2016: Phase 1, Face-to-face interviews

The National Beef Quality Audit (NBQA) is conducted every 5 yr and was most recently again conducted in 2016. Face-to-face interviews gauged progress in quality associated with live cattle production using procedures first utilized in NBQA 2011. The 2016 NBQA was the first in which interviews concerning fed steers and heifers were combined with an audit of market cow and bull beef. Face-to-face interviews were designed to illicit definitions for beef quality, estimate willingness to pay (WTP) for quality attributes, establish relative importance rankings for important quality factors, and assess images, strengths, weaknesses, potential threats, and shifting trends in the beef industry since the 2011 audit. Individuals making purchasing decisions in 5 market sectors of the steer/heifer and cow/bull beef supply chain were interviewed, including packers (n = 36), retailers (including large and small supermarket companies and warehouse food sales companies; n = 35), food service operators (including quick-serve, full-service, and institutional establishments; n = 29), further processors (n = 64), and peripherally-related government and trade organizations (GTO; n = 30). Face-to-face interviews were conducted between January and November of 2016 using a designed dynamic routing system. Definitions (as described by interviewees) for 7 pre-determined quality factors, including: (1) How and where the cattle were raised, (2) Lean, fat, and bone, (3) Weight and size, (4) Visual characteristics, (5) Food safety, (6) Eating satisfaction, and (7) Cattle genetics were recorded verbatim and categorized into similar responses for analysis. Compared to NBQA-2011, a higher percentage of companies were willing to pay premiums for guaranteed quality attributes, but overall were willing to pay lower average premiums than the companies interviewed in 2011. Food safety had the highest share of preference among all interviewees, generating a double-digit advantage over any other quality factor. The 2 beef industries have an overall positive image among interviewees, and despite lingering weaknesses, product quality continued to be at the forefront of the strengths category for both steer and heifer beef and market cow and bull beef.

National Beef Tenderness Survey—2015: Palatability and Shear Force Assessments of Retail and Foodservice Beef

Beef retail steaks from establishments across 11 US cities and beef foodservice steaks from establishments in 6 US cities were evaluated using Warner-Bratzler shear (WBS) force and consumer sensory panels. The average post-fabrication aging time of steaks at retail establishments was 25.9 d with a range of 6 to 102 d, and those from foodservice establishments averaged 31.5 d with a range of 3 to 91 d. The retail steaks with the lowest WBS value (P < 0.05) was the boneless top loin, compared to the top round steaks, which had the higher (P < 0.05) average WBS value. For the foodservice sector, top loin and ribeye steaks had the lowest (P < 0.05) WBS values, whereas the top sirloin represented the highest (P < 0.05) WBS values. The top blade retail steaks received among the highest consumer ratings (P < 0.05), whereas the top round and bottom round steaks received among the lowest (P < 0.05) consumer ratings for overall liking, tenderness liking, tenderness level, flavor liking, and juiciness liking. For the foodservice sector, the ribeye and top loin steaks were rated higher (P < 0.05) than top sirloin steaks for all consumer rating categories. The WBS values and sensory ratings were comparable to previous surveys, indicating no substantial changes in tenderness. Additional emphasis in improving the tenderness of top and bottom round steaks is necessary to increase consumer acceptability of these cuts.

Assessment of Postmortem Aging Effects on Texas-style Barbecue Beef Briskets

Palatability traits (tenderness, juiciness, flavor, and overall liking) of beef briskets (n = 48) were evaluated for 3 different postmortem aging period comparisons: 7 d vs. 21 d (Set 1), 21 d vs. 35 d (Set 2), and 7 d vs. 35 d (Set 3). Briskets were prepared as Texas-style barbecue by seasoning with salt and pepper and smoking with oak wood over a long period (approx. 11 h) using a commercial oven designed for such purposes until deemed tender (approx. 85°C internal temperature). Within each treatment set, Warner-Bratzler shear (WBS) force measurements did not differ (P > 0.05) between aging days; however, WBS force measurements for point (Mm. pectorales superficiales composed of the M. pectoralis transversus and M. pectoralis descendens) were lower (P < 0.05) compared to the flat portions (M. pectorals profundus) within each aging set. Consumer panelists did not (P > 0.05) detect differences between aging days within each set for overall liking, flavor liking, tenderness liking, and juiciness liking. Conversely, differences were found between brisket point and flat portions; Set 1 differed for flavor liking (flat > point; P = 0.0348) and juiciness liking (point > flat; P = 0.0004), Set 2 differed for overall liking (flat > point; P = 0.0499) and juiciness liking (point > flat; P < 0.0001), and Set 3 differed for overall liking (flat > point; P = 0.0296) and juiciness liking (point > flat; P = 0.0112). Our findings indicate postmortem aging did not improve beef brisket palatability, but we did note differences between point and flat portions. Preparing beef briskets as Texas-style barbecue resulted in products with low WBS values and high consumer palatability ratings, which helps demonstrate why barbecued briskets are so popular.

Assessment of Postmortem Aging Effects on Texas-style Barbecue Beef Briskets

Palatability traits (tenderness, juiciness, flavor, and overall liking) of beef briskets (n = 48) were evaluated for 3 different postmortem aging period comparisons: 7 d vs. 21 d (Set 1), 21 d vs. 35 d (Set 2), and 7 d vs. 35 d (Set 3). Briskets were prepared as Texas-style barbecue by seasoning with salt and pepper and smoking with oak wood over a long period (approx. 11 h) using a commercial oven designed for such purposes until deemed tender (approx. 85°C internal temperature). Within each treatment set, Warner-Bratzler shear (WBS) force measurements did not differ (P > 0.05) between aging days; however, WBS force measurements for point (Mm. pectorales superficiales composed of the M. pectoralis transversus and M. pectoralis descendens) were lower (P < 0.05) compared to the flat portions (M. pectorals profundus) within each aging set. Consumer panelists did not (P > 0.05) detect differences between aging days within each set for overall liking, flavor liking, tenderness liking, and juiciness liking. Conversely, differences were found between brisket point and flat portions; Set 1 differed for flavor liking (flat > point; P = 0.0348) and juiciness liking (point > flat; P = 0.0004), Set 2 differed for overall liking (flat > point; P = 0.0499) and juiciness liking (point > flat; P < 0.0001), and Set 3 differed for overall liking (flat > point; P = 0.0296) and juiciness liking (point > flat; P = 0.0112). Our findings indicate postmortem aging did not improve beef brisket palatability, but we did note differences between point and flat portions. Preparing beef briskets as Texas-style barbecue resulted in products with low WBS values and high consumer palatability ratings, which helps demonstrate why barbecued briskets are so popular.

National Beef Quality Audit-2016: Transportation, mobility, and harvest-floor assessments of targeted characteristics that affect quality and value of cattle, carcasses, and by-products

The National Beef Quality Audit-2016 (NBQA-2016) was conducted to assess current transportation, mobility, and quality characteristics of U.S. fed steers and heifers. Data were collected at 17 beef processing facilities between March and November 2016. About 8,000 live cattle were evaluated for transportation and mobility, and about 25,000 carcasses were evaluated on the slaughter floor. Cattle were in transit to the slaughter facility for a mean duration of 2.7 h from a mean distance of 218.5 km using trailers with dimensions ranging from 17.84 m² to 59.09 m². Area allotted per animal averaged 1.13 m² and ranged from 0.85 m² to 2.28 m². A total of 96.8% of cattle received a mobility score of 1 (walks easily, no apparent lameness). Identification types (35.1% had multiple) were lot visual tags (61.5%), individual tags (55.0%), electronic tags (16.9%), metal-clip tags (9.2%), bar-coded tags (0.05%), wattles (0.01%), and other (2.6%). Cattle were black-hided (57.8%), Holstein (20.4%), red-hided (10.5%), yellow-hided (4.8%), gray-hided (2.9%), brown-hided (1.3%), and white-hided (1.1%). Unbranded hides were observed on 74.3% of cattle; 18.6% had brands located on the butt, 6.3% on the side, and 1.3% on the shoulder (values exceed 100% due to multiple brands). For hide-on carcasses, 37.7% displayed no mud or manure; specific locations for mud or manure were legs (40.8%), belly (33.0%), tail region (15.5%), side (6.8%), and top-line (3.9%). Cattle without horns represented 83.3% of the sample, and cattle that did have horns measured: < 2.54 cm (5.5%), 2.54 to 12.7 cm (8.3%), and > 12.7 cm (2.9%). Carcasses without bruises represented 61.1% of those sampled, whereas 28.2% had 1, 8.2% had 2, 2.1% had 3, and 0.3% had 4 bruises. Of those carcasses with a bruise, the bruise was located on the loin (29.7%), round (27.8%), chuck (16.4%), rib (14.4%), and brisket/plate/flank (11.6%). Frequencies of offal condemnations were livers (30.8%), lungs (18.2%), viscera (16.3%), hearts (11.1%), heads (2.7%), and tongues (2.0%). Compared to NBQA-2011, fewer cattle were identified for traceability, fewer were black-hided, a greater number were Holstein cattle, more with no brand and no horns, fewer without bruises, more liver, lung, and viscera condemnations, and fewer heads and tongues were condemned. The NBQA remains an influential survey for the U.S. beef industry to provide benchmarks and strategic plans for continued improvement of beef quality and consistency.

Phase I of The National Beef Quality Audit-2011: quantifying willingness-to-pay, best-worst scaling, and current status of quality characteristics in different beef industry marketing sectors

The National Beef Quality Audit (NBQA)-2011 benchmarked the current status of and assessed progress being made toward quality and consistency of U.S. cattle, carcasses, and beef products after the completion of the first NBQA in 1991. Unlike previous NBQA, objectives of the 2011 Phase I study were to determine how each beef market sector defined 7 quality categories, estimate willingness-to-pay (WTP) for the same quality categories by market sector, and establish a best-worst (B/W) scaling for the quality categories. Structured face-to-face interviews were conducted and responses were recorded using dynamic routing software over an 11-mo period (February to December 2011) with decision makers in each of the following beef market sectors: Feeders (n = 59), Packers (n = 26), Food Service, Distribution, and Further Processors (n = 48), Retailers (n = 30), and Government and Allied Industries (n = 47). All respondents participated in a structured interview consisting of WTP and B/W questions that were tied to 7 quality categories and then were asked to "define" each of the 7 categories in terms of what the category meant to them, resulting in completely unbiased results. The 7 quality categories were a) how and where the cattle were raised, b) lean, fat, and bone, c) weight and size, d) cattle genetics, e) visual characteristics, f) food safety, and g) eating satisfaction. Overall, "food safety" and "eating satisfaction" were the categories of greatest and second most importance, respectively, to all beef market sectors except for Feeders. Feeders ranked "how and where the cattle were raised" and "weight and size" as the most important and second most important, respectively. Overall, "how and where the cattle were raised" had the greatest odds of being considered a nonnegotiable requirement before the raw material for each sector would be considered for purchase and was statistically more important (P < 0.05) as a requirement for purchase than all other categories except "food safety." When all market sectors were considered, "eating satisfaction" was shown to generate the greatest average WTP percentage premium (11.1%), but that WTP premium value only differed statistically (P < 0.05) from "weight and size" (8.8%). Most notably, when a sector said that "food safety" was a nonnegotiable requirement, no sector was willing to purchase the product at a discounted price if the "food safety" of the product could not be assured.

National Beef Quality Audit-2011: Harvest-floor assessments of targeted characteristics that affect quality and value of cattle, carcasses, and byproducts

The National Beef Quality Audit-2011 (NBQA-2011) was conducted to assess targeted characteristics on the harvest floor that affect the quality and value of cattle, carcasses, and byproducts. Survey teams evaluated approximately 18,000 cattle/carcasses between May and November 2011 in 8 beef processing facilities. Cattle identification methods were lot visual tags (85.7%), individual visual tags (50.6%), electronic tags (20.1%), metal-clip tags (15.7%), other (5.3%), none (2.5%), and wattles (0.5%). Hide colors or breed types were black (61.1%), red (12.8%), yellow (8.7%), Holstein (5.5%), brown (5.0%), gray (5.0%), white (1.4%), and brindle (1.0%). Brand frequencies were none (55.2%), 1 (40.4%), 2 (4.4%), and 3 or more (0.04%) brands, and brands were located on the butt (35.2%), side (9.0%), and shoulder (2.5%). Hide locations of mud or manure were no mud/manure (49.2%), legs (36.8%), belly (23.7%), side (14.9%), top-line (11.0%), and tail region (13.7%). There were 76.2% of cattle without horns, and the majority of those with horns (71.6%) were between 0 cm and 12.7 cm in length. Permanent incisor numbers were zero (87.3%), 1 (1.4%), 2 (8.0%), 3 (0.9%), 4 (1.9%), 5 (0.3%), 6 (0.2%), 7 (0.1%), and 8 (0.02%). Most carcasses (77.0%) were not bruised, 18.7% had 1 bruise, 3.4% had 2 bruises, 0.6% had 3 bruises, and 0.3% had more than 3 bruises. Bruise locations were loin (50.1%), rib (21.3%), chuck (13.8%), round (7.3%), and brisket/flank/plate (7.5%). Condemnation item and incidence were whole carcass (none recorded), liver (20.9%), lungs (17.3%), tongue (10.0%), viscera (9.3%), and head (7.2%). Compared with the NBQA-2005, the NBQA-2011 had an increased percentage of black-hided cattle (56.3 vs. 61.1%), more cattle with brands (38.7 vs. 44.8%), and more cattle with some form of identification (93.3 vs. 97.5%). In addition, there was a lesser percentage of carcasses with bruising in 2011 (23.0%) than in 2005 (35.2%), as well as a smaller percentage of carcasses with more than 1 bruise (2005 = 9.4% vs. 2011 = 4.2%). Compared with the 2005 audit, a similar percentage of the cattle were deemed 30 mo of age or older using dentition (2005 = 2.7% vs. 2011 = 3.3%). The information from NBQA-2011 helps the beef industry measure progress against previous NBQA assessments and provides a benchmark for future educational and research activities.

National Beef Quality Audit-2011: Survey of instrument grading assessments of beef carcass characteristics

The instrument grading assessments for the 2011 National Beef Quality Audit evaluated seasonal trends of beef carcass quality and yield attributes over the course of the year. One week of instrument grading data, HCW, gender, USDA quality grade (QG), and yield grade (YG) factors, were collected every other month (n = 2,427,074 carcasses) over a 13-mo period (November 2010 through November 2011) from 4 beef processing corporations, encompassing 17 federally inspected beef processing facilities, to create a "snapshot" of carcass quality and yield attributes and trends from carcasses representing approximately 8.5% of the U.S. fed steer and heifer population. Mean yield traits were YG (2.86), HCW (371.3 kg), fat thickness (1.19 cm.), and LM area (88.39 cm(2)). The YG distribution was YG 1, 15.7%; YG 2, 41.0%; YG 3, 33.8%; YG 4, 8.5%; and YG 5, 0.9%. Distribution of HCW was <272.2 kg, 1.6%; 272.2 to 453.6 kg, 95.1%; and ≥453.6 kg, 3.3%. Monthly HCW means were November 2010, 381.3 kg; January 2011, 375.9 kg; March 2011, 366.2 kg; May 2011, 357.9 kg; July 2011, 372.54 kg; September 2011, 376.1 kg; and November 2011, 373.5 kg. The mean fat thickness for each month was November 2010, 1.30 cm; January 2011, 1.22 cm; March 2011, 1.17 cm; May 2011, 1.12 cm; July 2011, 1.19 cm; September 2011, 1.22 cm; and November 2011, 1.22 cm. The overall average marbling score was Small(49). The USDA QG distribution was Prime, 2.7%; Top Choice, 22.9%; Commodity Choice, 38.6%; and Select, 31.5%. Interestingly, from November to May, seasonal decreases (P < 0.001) in HCW and fat thicknesses were accompanied by increases (P < 0.001) in marbling. These data present the opportunity to further investigate the entire array of factors that determine the value of beef. Data sets using the online collection of electronic data will likely be more commonly used when evaluating the U.S. fed steer and heifer population in future studies.

National Beef Quality Audit-2011: In-plant survey of targeted carcass characteristics related to quality, quantity, value, and marketing of fed steers and heifers

The 2011 National Beef Quality Audit (NBQA-2011) assessed the current status of quality and consistency of fed steers and heifers. Beef carcasses (n = 9,802), representing approximately 10% of each production lot in 28 beef processing facilities, were selected randomly for the survey. Carcass evaluation for the cooler assessment of this study revealed the following traits and frequencies: sex classes of steer (63.5%), heifer (36.4%), cow (0.1%), and bullock (0.03%); dark cutters (3.2%); blood splash (0.3%); yellow fat (0.1%); calloused rib eye (0.05%); overall maturities of A (92.8%), B (6.0%), and C or greater (1.2%); estimated breed types of native (88.3%), dairy type (9.9%), and Bos indicus (1.8%); and country of origin of United States (97.7%), Mexico (1.8%), and Canada (0.5%). Certified or marketing program frequencies were age and source verified (10.7%), ≤A(40) (10.0%), Certified Angus Beef (9.3%), Top Choice (4.1%), natural (0.6%), and Non-Hormone-Treated Cattle (0.5%); no organic programs were observed. Mean USDA yield grade (YG) traits were USDA YG (2.9), HCW (374.0 kg), adjusted fat thickness (1.3 cm), LM area (88.8 cm2), and KPH (2.3%). Frequencies of USDA YG distributions were YG 1, 12.4%; YG 2, 41.0%; YG 3, 36.3%; YG 4, 8.6%; and YG 5, 1.6%. Mean USDA quality grade (QG) traits were USDA quality grade (Select(93)), marbling score (Small(40)), overall maturity (A(59)), lean maturity (A(54)), and skeletal maturity (A(62)). Frequencies of USDA QG distributions were Prime, 2.1%; Choice, 58.9%; Select, 32.6%; and Standard or less, 6.3%. Marbling score distribution was Slightly Abundant or greater, 2.3%; Moderate, 5.0%; Modest, 17.3%; Small, 39.7%; Slight, 34.6%; and Traces or less, 1.1%. Carcasses with QG of Select or greater and YG 3 or less represented 85.1% of the sample. This is the fifth benchmark study measuring targeted carcass characteristics, and information from this survey will continue to help drive progress in the beef industry. Results will be used in extension and educational programs as teaching tools to inform beef producers and industry professionals of the current state of the U.S. beef industry.

Salmonella prevalence in bovine lymph nodes differs among feedyards

Lymphatic tissue, specifically lymph nodes, is commonly incorporated into ground beef products as a component of lean trimmings. Salmonella and other pathogenic bacteria have been identified in bovine lymph nodes, which may impact compliance with the Salmonella performance standards for ground beef established by the U.S. Department of Agriculture. Although Salmonella prevalence has been examined among lymph nodes between animals, no data are currently available regarding feedyard origin of the cattle and Salmonella prevalence. Bovine lymph nodes (279 superficial cervical plus 28 iliofemoral = 307) were collected from beef carcasses at a commercial beef harvest and processing plant over a 3-month period and examined for the prevalence of Salmonella. Cattle processed were from seven feedyards (A through G). Salmonella prevalence was exceptionally low (0% of samples were positive ) in cattle from feedyard A and high (88.2%) in cattle from feedyard B. Prevalence in the remaining feedyards ranged widely: 40.0% in feedyard C, 4.0% in feedyard D, 24.0% in feedyard E, 42.9% in feedyard F, and 40.0% in feedyard G. These data indicate the range of differences in Salmonella prevalence among feedyards. Such information may be useful for developing interventions to reduce or eliminate Salmonella from bovine lymph nodes, which would assist in the reduction of Salmonella in ground beef.

Effect of zilpaterol hydrochloride supplementation on cutability and subprimal yield of beef steer carcasses

Beef steers (n = 11,877) from 7 studies were fed zilpaterol hydrochloride (ZH) for 0 or 20 to 40 d before slaughter to determine the effects of ZH on subprimal weight and yield. Carcasses were selected based on mean HCW of treatment groups for fabrication into boneless, closely trimmed, or denuded subprimals, lean, fat, and bone. Data from the 7 trials were pooled for statistical analysis. Feeding ZH increased (P < 0.05) weights of all major subprimals compared with steers not supplemented with ZH. Also, subprimals from the hindquarter, including valuable cuts like the tenderloin, strip loin, and top sirloin butt, increased (P < 0.05) as a percentage of cold carcass weight from steers fed ZH. The tenderloin was 0.06 percentage units greater (P < 0.05), the strip loin was 0.08 percentage units greater (P < 0.05), and the top sirloin butt was 0.11 percentage units greater (P < 0.05) in ZH-fed steers when compared with steers not fed ZH. Supplementation of ZH greatly increased (P < 0.05) total saleable carcass yield by 1.76 percentage units, whereas ZH inclusion decreased (P < 0.05) the percentage of fat trim and bone by 0.58 and 1.10 percentage units, respectively. Therefore, ZH can be utilized by the beef industry to improve red meat yield efficiency throughout the beef production chain.

Predicting red meat yields in carcasses from beef-type and calf-fed Holstein steers using the United States Department of Agriculture calculated yield grade

Analyses were conducted to evaluate the ability of the USDA yield grade equation to detect differences in subprimal yield of beef-type steers and calf-fed Holstein steers that had been fed zilpaterol hydrochloride (ZH; Intervet Inc., Millsboro, DE) as well as those that had not been fed ZH. Beef-type steer (n = 801) and calf-fed Holstein steer (n = 235) carcasses were fabricated into subprimal cuts and trim. Simple correlations between calculated yield grades and total red meat yields ranged from -0.56 to -0.62 for beef-type steers. Reliable correlations from calf-fed Holstein steers were unobtainable; the probability of a type I error met or exceeded 0.39. Linear models were developed for the beef-type steers to predict total red meat yield based on calculated USDA yield grade within each ZH duration. At an average calculated USDA yield grade of 2.9, beef-type steer carcasses that had not been fed ZH had an estimated 69.4% red meat yield, whereas those fed ZH had an estimated 70.7% red meat yield. These results indicate that feeding ZH increased red meat yield by 1.3% at a constant calculated yield grade. However, these data also suggest that the calculated USDA yield grade score is a poor and variable estimator (adjusted R(2) of 0.31 to 0.38) of total red meat yield of beef-type steer carcasses, regardless of ZH feeding. Moreover, no relationship existed (adjusted R(2) of 0.00 to 0.01) for calf-fed Holstein steer carcasses, suggesting the USDA yield grade is not a valid estimate of calf-fed Holstein red meat yield.

Effects of feeding zilpaterol hydrochloride for twenty to forty days on carcass cutability and subprimal yield of calf-fed Holstein steers

Zilpaterol hydrochloride (ZH) is designed to increase carcass leanness, chilled side weight (CSW), and percent saleable yield. The objective of this study was to evaluate the effect of a single dose of ZH on cutability and subprimal yield of calf-fed Holstein steers when fed for increasing durations. Two hundred forty steers were fed 8.3 mg/kg of ZH on a DM basis for 0, 20, 30, or 40 d, with a 3-d withdrawal before slaughter. After slaughter, steers were fabricated into 4 pieces (round, loin/flank, rib/plate, and chuck), packaged in combos, shipped to 2 locations, and further fabricated into subprimal pieces and trim. Trim was collected from each primal and separated into groups based on composition of 90, 80, and 50% lean. Zilpaterol hydrochloride increased (P = 0.01) CSW by 6.22 kg and saleable yield by 6.4 kg when included in the diet for 20 d. Furthermore, saleable yield as a percentage of CSW was increased (P = 0.03) 1.18 percentage units when included in the diet for 20 d. Steers fed ZH for 20 d had heavier strip loins (4.47 vs. 4.12 kg, P = 0.02), tenderloins (2.75 vs. 2.49 kg, P = 0.02), and ribeye rolls (5.74 vs. 5.30 kg, P = 0.01) than steers not fed ZH. These advantages are further demonstrated as a percentage of CSW. Strip loins (P = 0.06), tenderloins (P = 0.04), and ribeye rolls (P = 0.04) of ZH-fed steers had a greater percentage of CSW than controls. Zilpaterol hydrochloride also increased the percentage of CSW of the 3 primary components of the round when fed for 20 d. The knuckle was 0.10 percentage units heavier (P = 0.11), the top round was 0.24 percentage units heavier (P = 0.04), and the bottom round was 0.22 percentage units heavier (P = 0.03) in ZH-fed steers when compared with steers not fed ZH. Based on these data, it can be concluded that ZH significantly increased subprimal cutting weights, yields, and percentage saleable yield of calf-fed Holstein steers when fed for at least 20 d before slaughter. Zilpaterol hydrochloride increased percentage of CSW of subprimal cuts from Holstein steers in the round and to a lesser degree in the loin.

National Beef Quality Audit-2005: survey of targeted cattle and carcass characteristics related to quality, quantity, and value of fed steers and heifers

The National Beef Quality Audit-2005 assessed the current status of quality and consistency of US fed steers and heifers. Hide colors or breed type were black (56.3%), red (18.6%), Holstein (7.9%), gray (6.0%), yellow (4.9%), brown (3.0%), white (2.3%), and brindle (1.0%). Identification method and frequency were lot visual tags (63.2%), individual visual tags (38.7%), metal-clip tags (11.8%), electronic tags (3.5%), bar-coded tags (0.3%), by other means (2.5%), and without identification (9.7%). Brand frequencies were no (61.3%), 1 (35.1%), and 2 or more (3.6%), and brands were located on the butt (26.5%), side (7.4%), and shoulder (1.2%). There were 22.3% of cattle without horns, and the majority of those with horns (52.2%) were between 2.54 and 12.7 cm in length. Percentages of animals with mud or manure on specific body locations were none (25.8%), legs (61.4%), belly (55.9%), side (22.6%), and top-line (10.0%). Permanent incisor number and occurrence were zero (82.2%), 1 (5.2%), 2 (9.9%), 3 (0.4%), 4 (1.2%), 5 (0.1%), 6 (0.3%), 7 (0.0%), and 8 (0.7%). Most carcasses (64.8%) were not bruised, 25.8% had one bruise, and 9.4% had multiple bruises. Bruise location and incidence were round (10.6%), loin (32.6%), rib (19.5%), chuck (27.0%), and brisket, flank, and plate (10.3%). Condemnation item and incidence were liver (24.7%), lungs (11.5%), tripe (11.6%), heads (6.0%), tongues (9.7%), and carcasses (0.0%). Carcass evaluation revealed these traits and frequencies: steer (63.7%), heifer (36.2%), bullock (0.05%), and cow (0.04%) sex classes; dark-cutters (1.9%); A (97.1%), B (1.7%), and C or older (1.2%) overall maturities; and native (90.9%), dairy-type (8.3%), and Bos indicus (0.8%) estimated breed types. Mean USDA yield grade (YG) traits were USDA YG (2.9), HCW (359.9 kg), adjusted fat thickness (1.3 cm), LM area (86.4 cm(2)), and KPH (2.3%). The USDA YG were YG 1 (16.5%), YG 2 (36.3%), YG 3 (33.1%), YG 4 (11.8%), and YG 5 (2.3%). Mean USDA quality grade traits were USDA quality grade (Select(90)), marbling score (Small(32)), overall maturity (A(64)), lean maturity (A(57)), and skeletal maturity (A(68)). Marbling score distribution was Slightly Abundant or greater (2.7%), Moderate (4.3%), Modest (14.4%), Small (34.5%), Slight (41.2%), and Traces or less (2.9%). This information helps the beef industry measure progress and provides a benchmark for future educational and research activities.

Dry versus wet aging of beef: Retail cutting yields and consumer sensory attribute evaluations of steaks from ribeyes, strip loins, and top sirloins from two quality grade groups

Top Choice (n=48) and Select (n=48) paired bone-in ribeye rolls, bone-in strip loins, and boneless top sirloin butts were assigned randomly to one of two aging treatments, dry or wet, and were aged for 14, 21, 28 or 35d. Cutting tests, performed to determine retail yields and processing times, showed dry-aged subprimals had lower total saleable yield percentages and increased processing times compared to wet-aged subprimals. Sensory and Warner-Bratzler shear evaluation was conducted to determine palatability characteristics. For the most part, aging treatment and aging period did not affect consumer sensory attributes. However, ribeye and top loin steaks from the Top Choice quality grade group received higher sensory ratings than their Select counterparts. For top sirloin steaks, no consumer sensory attributes were affected by aging treatment, aging period, or quality grade group.

Dry versus wet aging of beef: Retail cutting yields and consumer palatability evaluations of steaks from US Choice and US Select short loins

Paired beef short loins from US Choice (n=48) and US Select (n=48) carcasses were assigned to be dry or wet aged for 14, 21, 28 or 35d. After aging, short loins were processed to determine retail yields and processing times. Upon completion of cutting tests, steaks were served to consumers to assess palatability characteristics. Retail cutting tests showed that dry-aged short loins had reduced yields and increased cutting times when compared to wet-aged short loins. Consumers were unable to determine differences between dry- and wet-aged steaks and for aging periods; however, USDA quality grade had a significant impact on consumer perception of palatability attributes.

Retail cutting characteristics for US Choice and US Select beef subprimals

US Choice (Ch) and US Select (Se) beef subprimals from the rib, chuck, plate, loin, and round were obtained to conduct retail cutting tests. Subprimals were merchandised into bone-in or boneless retail cuts and associated components by experienced retail meat merchandisers. These Se subprimals had less (P<0.05) trimmable fat than their Ch counterparts: ball tip, top sirloin, outside round, inside round, and ribeye. Se inside rounds, outside rounds, eye of rounds, boneless striploins, and ball tips had greater (P<0.05) purge losses than the same cuts from Ch. The only subprimals where grade impacted total saleable yield were the top (inside) rounds (Ch=80.13%, Se=87.34%; P=0.004) and outside rounds cut into roasts, steaks, and cubed steaks (Ch=87.61%, Se=90.28%; P=0.05). Methods to increase retail yields from beef subprimals should consider minimizing purge and increasing cutting efficiencies in addition to reducing fat trim.

Safety and efficacy of the extended iliofemoral approach in the treatment of complex fractures of the acetabulum

There remains uncertainty about the most effective surgical approach in the treatment of complex fractures of the acetabulum. We have reviewed the experience of a single surgeon using the extended iliofemoral approach, as described by Letournel.

A review of the database of such fractures identified 106 patients operated on using this approach with a minimum follow-up of two years. All data were collected prospectively. The fractures involved both columns in 64 (60%). Operation was undertaken in less than 21 days after injury in 71 patients (67%) and in 35 (33%) the procedure was carried out later than this. The reduction of the fracture was measured on plain radiographs taken after operation and defined as anatomical (0 to 1 mm of displacement); imperfect (2 to 3 mm) or poor (> 3 mm). The functional outcome was measured by the modified Merle d’Aubigné and Postel score. The mean follow-up was for 6.3 years (2 to 17).

All patients achieved union of the fractures. The reduction was graded as anatomical in 76 (72%) of the patients, imperfect in 23 (22%), and poor in six (6%). The mean Merle d’Aubigné and Postel score was 15 (5 to 18) with 68 patients (64%) showing good or excellent and 38 (36%) fair or poor results. Function correlated significantly with the accuracy of the reduction (p < 0.009). Significant heterotopic ossification developed in 32 patients (30%) and was associated with a worse mean Merle d’Aubigné and Postel score of 13.7.

The extended iliofemoral approach can be performed safely in selected complex acetabular fractures with an acceptable clinical outcome and rate of complications. Effective prophylaxis against heterotopic ossification should be strongly considered.

Retail yields from beef chuck and round subprimals from two grade groups when merchandised as single muscle cuts

Beef subprimals from two different grade groups were obtained from two beef processors to assist in updating the Beef Computer Assisted Retail Decision Support (CARDS) program with new fabrication styles. The grade groups consisted of Top Choice (containing subprimals from carcasses with a Modest or Moderate degree of marbling) and Select (containing subprimals from carcasses with a Slight degree of marbling). Subprimals (shoulder clod; top blade, roast; arm roast; knuckle, peeled; outside round, flat) were separated into individual muscles and fabricated into retail cuts by professional retail meat cutters. Mean retail cutting yields and labor requirements were calculated from observed weights (kilograms) and processing times (seconds). Data were analyzed to determine means and standard errors of percentage yield and processing times for subprimals in each grade group, and comparisons were made between grade groups. Generally, there were few differences in processing times between Top Choice and Select subprimals, and the trimming phase required the most time to complete for each subprimal. Differences (P < 0.05) were observed in saleable yield between Top Choice and Select subprimals for the shoulder clod (Top Choice = 73.89%; Select = 78.49%), top blade, roast (Top Choice = 84.36%; Select = 86.70%), and outside round, flat (Top Choice = 85.99%; Select = 91.34%). Trimmable fat differed (P < 0.05) between Top Choice and Select subprimals: shoulder clod (Top Choice = 25.30%; Select = 20.85%), top blade, roast (Top Choice = 14.88%; Select = 12.59%), arm roast (Top Choice = 8.35%; Select = 7.47%), knuckle (Top Choice = 5.72%; Select = 2.73%), and outside round, flat (Top Choice = 13.82%; Select = 7.26%). Most of the differences in saleable yields were related to less trimmable fat for Select subprimals, which also required less trimming time than Top Choice subprimals. These data will serve to update the Beef CARDS program and will provide retailers and foodservice operators with third-party cutting yield and time allocation information.

National Beef Quality Audit-2000: survey of targeted cattle and carcass characteristics related to quality, quantity, and value of fed steers and heifers

The National Beef Quality Audit-2000 was conducted to assess the current status ofthe quality and consistency of U.S. fed steers and heifers. Between May and November 2000, survey teams assessed hide condition (n = 43,415 cattle for color, brands, mud/manure), bruises (n = 43,595 carcasses), offal and carcass condemnation (n = 8,588 cattle), and carcass quality and yield information (n = 9,396 carcasses) in 30 U.S. beef packing plants. Hide colors were black (45.1%), red (31.0%), yellow (8.0%), Holstein (5.7%), gray (4.0%), white (3.2%), brown (1.7%), and brindle (1.3%). Brand frequencies were no (49.3%), one (46.2%), and two or more (4.4%), and brands were located on the butt (36.3%), side (13.7%), and shoulder (3.6%). Most cattle had no (18.0%) or a small amount (55.8%) of mud/manure on their hides, and they had no (77.3%) horns. Most carcasses (53.3%) were not bruised, 30.9% had one bruise, and 15.8% had multiple bruises. Bruise location and incidence were round (14.9%), loin (25.9%), rib (19.4%), chuck (28.2%), and brisket, flank, and plate (11.6%). Condemnation item and incidence were liver (30.3%), lungs (13.8%), tripe (11.6%), heads (6.2%), tongues (7.0%), and carcasses (0.1%). Carcass evaluation revealed these traits and frequencies: steer (67.9%), heifer (31.8%), and bullock (0.3%) sex-classes; dark-cutters (2.3%); A (96.6%), B (2.5%), and C or older (0.9%) overall maturities; and native (90.1%), dairy-type (6.9%), and Bos indicus (3.0%) breed-types. Mean USDA yield grade traits were USDA yield grade (3.0), carcass weight (356.9 kg), adjusted fat thickness (1.2 cm), longissimus muscle area (84.5 cm2), and kidney, pelvic, and heart fat (2.4%). USDA yield grades were Yield Grade 1 (12.2%), Yield Grade 2 (37.4%), Yield Grade 3 (38.6%), Yield Grade 4 (10.4%), and Yield Grade 5 (1.3%). Mean USDA quality grade traits were USDA quality grade (Select85), marbling score (Small23), overall maturity (A66), lean maturity (A65), and skeletal maturity (A67). Marbling score distribution was Slightly Abundant or higher (2.3%), Moderate (4.8%), Modest (13.1%), Small (33.3%), Slight (43.3%), and Traces (3.4%). USDA quality grades were Prime (2.0%), Choice (49.1%), Select (42.3%), Standard (5.6%), and Commercial, Utility, Cutter, and Canner (0.9%). This information will help the beef industry measure progress compared to the past two surveys and will provide a benchmark for future educational and research activities.

Foodservice yield and fabrication times for beef as influenced by purchasing options and merchandising styles

Selected beef subprimals were obtained from fabrication lines of three foodservice purveyors to assist in the development of a software support program for the beef foodservice industry. Subprimals were fabricated into bone-in or boneless foodservice ready-to-cook portion-sized cuts and associated components by professional meat cutters. Each subprimal was cut to generate mean foodservice cutting yields and labor requirements, which were calculated from observed weights (kilograms) and processing times (seconds). Once fabrication was completed, data were analyzed to determine means and standard errors of percentage yields and processing times for each subprimal. Subprimals cut to only one end point were evaluated for mean foodservice yields and processing times, but no comparisons were made within subprimal. However, those traditionally cut into various end points were additionally compared by cutting style. Subprimals cut by a single cutting style included rib, roast-ready; ribeye roll, lip-on, bone-in; brisket, deckle-off, boneless; top (inside) round; and bottom sirloin butt, flap, boneless. Subprimals cut into multiple end points or styles included ribeye, lip-on; top sirloin, cap; tenderloin butt, defatted; shortloin, short-cut; strip loin, boneless; top sirloin butt, boneless; and tenderloin, full, side muscle on, defatted. Mean yields of portion cuts, and mean fabrication times required to manufacture these cuts differed (P < 0.05) by cutting specification of the final product. In general, as the target portion size of fabricated steaks decreased, the mean number of steaks derived from any given subprimal cut increased, causing total foodservice yield to decrease and total processing time to increase. Therefore, an inverse relationship tended to exist between processing times and foodservice yields. With a method of accurately evaluating various beef purchase options, such as traditional commodity subprimals, closely trimmed subprimals, and pre-cut portion steaks in terms of yield and labor cost, foodservice operators will be better equipped to decide what option is more viable for their operation.

National Beef Tenderness Survey-1998

Fifty-six retail stores representing 15 retail chains and 14 foodservice facilities in eight U.S. cities were sampled to determine the tenderness of beef steaks at retail and foodservice levels based on Warner-Bratzler shear (WBS) values and consumer evaluation panels. Retail consumer panels were conducted at five universities. Each retail and foodservice steak was evaluated using 10-point scales. Steaks were divided into the following quality groups for statistical analysis: Prime, Top Choice, Choice, Select, and Lean or No Roll. Quality group had no effect on WBS values of retail clod, chuck roll, top round, bottom round, eye of round, top loin, top sirloin, or ribeye steaks but did (P < .05) affect values for the T-bone/porterhouse. The percentages of retail top round, eye of round, and bottom round steaks with a WBS force > 3.9 kg were 39.6, 55.9, and 68.0, respectively. Foodservice ribeye, top loin, and top sirloin steaks had WBS values less than 3.4 kg for all quality groups, with Prime ribeye steaks having lower (P < .05) WBS values than ribeyes from the other quality groups. With the exception of the retail ribeye steak, quality group did not affect consumer sensory ratings of retail and foodservice steaks. Average postfabrication aging times were 32 d for foodservice subprimals and 19 d for retail cut subprimals. These data indicate that improvements in the tenderness of retail cuts from the round are needed. Finally, quality group had little or no effect on consumer sensory evaluations and WBS values of retail and foodservice steaks used in this study.

Carcass traits and retail display-life of chops from different goat breed types

Four groups of goats, Boer x Spanish, straightbred Spanish, Spanish x Angora, and straightbred Angora were slaughtered at a constant age according to accepted industry procedures. At 24 h postmortem, various carcass yield and quality measurements were taken. At 48 h postmortem, one side from each carcass was fabricated into major wholesale cuts for dissection into percentage lean, bone, and fat. Rib chops from the opposite side were fabricated, packaged, and displayed in a retail case. Trained panelists evaluated the rib chops over 4 d of retail display for lean color, surface discoloration, and overall appearance; packages were opened and analyzed for off-odor on d 4. When slaughtered at constant ages, Angora goats had lighter (P < .05) live and hot carcass weights than all other breed types, and Boer x Spanish goats had heavier (P < .05) live and carcass weights than Spanish goats. Live and carcass weights for Boer x Spanish and Spanish x Angora goats did not differ (P > .05). Carcasses from Angora goats had considerably smaller (P < .05) longissimus muscle areas than all other breed types. Carcasses from Spanish goats had lower (P < .05) carcass conformation scores than carcasses from Boer x Spanish goats but did not differ (P > .05) from carcasses of the other two breed types. Carcasses from Angora goats had smaller (P < .05) leg circumferences than the carcasses from Boer x Spanish and Spanish x Angora breed types. In general, carcasses from Boer x Spanish and Spanish goats possessed higher (P < .05) percentages of lean and lower (P < .05) percentages of fat for the side than did carcasses from Spanish x Angora and Angora goats. When the Spanish x Angora carcasses were compared to the Angora carcasses, it seemed that the addition of the Spanish breeding tended to increase lean and decrease fatness for most side or primal comparisons. There were no (P > .05) breed type or breed type x day effects for lean color, surface discoloration, overall appearance or off-odor; however, day of display did influence (P < .05) these traits. Crossing Spanish with Angora goats may be an option to improve carcass characteristics over that of straightbred Angora.

Effect of breed-type and feeding regimen on goat carcass traits

Meat-type (Boer x Spanish and Spanish) goats from two feeding regimens (feedlot and range) were slaughtered and live and carcass weights were obtained. At 24 h after death, various yield and quality measurements were collected. One side from each carcass was fabricated into major wholesale cuts for dissection into major carcass components. Feedlot goats had heavier (P<.05) live and carcass weights and carcasses that yielded more (P<.05) dissectible fat and lean and less (P<.05) bone, as a percentage of carcass weight, than did the carcasses of range goats. In the feedlot environment, Boer x Spanish goats had greater (P<.05) live weights, carcass weights, actual and adjusted fat thicknesses, carcass conformation scores, and leg circumference scores than did Spanish goats of similar age. The only breed-type differences that were significant after adjusting for live weight using analysis of covariance were that Boer x Spanish goats in the feedlot treatment had greater (P<.05) actual and adjusted fat thickness and carcass conformation than Spanish goats on the feedlot treatment. The Boer x Spanish goat carcass trait advantage could mainly be attributed to their larger size and enhanced capacity for growth.

Predicting carcass composition of beef cattle using ultrasound technology

We evaluated 20 slaughtered cattle with ultrasound before hide removal to predict fat thickness and ribeye area at the 12th rib for possible use in carcass composition prediction. Carcasses were fabricated into boneless subprimals that were trimmed progressively from 2.54 to 1.27 to .64 cm maximum fat trim levels. Stepwise regression was used to indicate the relative importance of variables in a model designed to estimate the percentage of boneless subprimals from the carcass at different external fat trim levels. Variables included those obtained on the slaughter floor (ultrasound fat thickness and ribeye area; estimated percentage of kidney, pelvic, and heart [KPH] fat; and warm carcass weight) and those obtained from carcasses following 24 h in the chill cooler (actual fat thickness, actual ribeye area, estimated percentage of KPH fat, warm carcass weight, and marbling score). At all different subprimal trim levels, percentage KPH was the first variable to enter the model. In the models using measures taken on the slaughter floor, ultrasound fat thickness was the only other variable to enter the model. Ultrasound fat thickness increased R2 and decreased residual standard deviation (RSD) in models predicting subprimals at 2.54-cm maximum fat trim; however, at 1.27- and .64-cm trim levels, R2 and RSD increased. Models using the same two variables (except actual fat instead of ultrasound) in the cooler were similar to those using data from the slaughter floor. However, as more cooler measurement variables entered the models, R2 increased and RSD decreased, explaining a greater amount of the variation in the equation. Ultrasonic evaluation on the slaughter floor may be of limited application compared with the greater accuracy found in chilled carcass assessment.

Retail yield and fabrication times for veal as influenced by purchasing options and merchandising styles

Twenty-nine selected styles of subprimals or sections of veal were obtained from a commercial facility to assist in the development of a support program for retailers. They were fabricated into bone-in or boneless retail cuts and associated components by trained meat cutters. Each style selected (n = 6) was used to generate mean retail yields and labor requirements, which were calculated from wholesale and retail weights and processing times. Means and standard errors for veal ribs consisting of five different styles (n = 30) concluded that style #2, 7-rib 4 (10 cm) x 4 (10 cm), had the lowest percentage of total retail yield (P < .05) owing to the greatest percentage of bone. Furthermore, rib style #2 required the longest total processing time (P < .05). Rib styles #3, 7-rib chop-ready, and #5, 6-rib chop ready, yielded the greatest percentage of total retail yield and also had the shortest total processing time (P < .05). Within veal loins, style #2, 4 (10 cm) x 4 (10 cm) loin kidney fat in, had the greatest percentage fat (P < .05). Loin styles #2 and #3, 4 (10 cm) x 4 (10 cm) loin special trimmed, generated more lean and fat trimmings and bone, resulting in lower percentage of total retail yields than loin style #1, 0 (0 cm) x 1 (2.5 cm) loin special trimmed (P < .05). Results indicated that bone-in subprimals and sections required more processing time if fabricated into a boneless end point. In addition, as the number of different retail cuts increased, processing times also increased.

National Beef Quality Audit-1995: survey of producer-related defects and carcass quality and quantity attributes

The National Beef Quality Audit-1995 was conducted to evaluate the progress of the beef industry since the time of the National Beef Quality Audit-1991 in improving quality and consistency of beef. Nine plants were assigned for auditing to Colorado State University, Oklahoma State University, and Texas A&M University. Personnel from each institution visited three of their nine plants twice, once in the spring/summer and once in the fall/winter. Data were collected on 50% of each lot on the slaughter floor and 10% in the cooler during a single day's production (one or two shifts, as appropriate). Of the cattle audited on the slaughter floor, 47.7% had no brands, 3.0% had a shoulder brand, 16.8% had a side brand, 38.7% had a butt brand, and 6.2% had brands in multiple locations. Data revealed that 51.6% of the carcasses had no bruises, 30.9% had one bruise, 12.8% had two bruises, 3.7% had three bruises, .9% had four bruises, and .1% had more than four bruises. In addition, 7.2% of the bruises evaluated were located on the round, 41.1% were on the loin, 20.8% on the rib, and 30.8% on the chuck. Livers, lungs, tripe, heads, tongues, and whole carcasses were condemned at rates of 22.2, 5.0, 11.0, .9, 3.8, and .1%, respectively. Mean USDA yield grade and quality grade traits were as follows: USDA yield grade, 2.8; carcass weight, 338.4 kg; adjusted fat thickness, 1.2 cm; longissimus muscle area, 81.9 cm2; kidney, pelvic, and heart fat, 2.1%; USDA quality grade, High Select; overall maturity, A60; and marbling score, Small-minus.

Influence of wholesale lamb marketing options and merchandising styles on retail yield and fabrication time

Lamb carcasses (n = 94) from five packing plants, selected to vary in weight class and fat thickness, were used to determine retail yield and labor requirements of wholesale lamb fabrication. Carcasses were allotted randomly according to weight class to be fabricated as whole carcasses (n = 20), three-piece boxes (n = 22), or subprimals (n = 52). Processing times (seconds) were recorded and wholesale and retail weights (kilograms) were obtained to calculate retail yield. Subprimals were fabricated into bone-in retail cuts or boneless or semi-boneless retail cuts. Retail yield for subprimal lamb legs decreased from 85.3 +/- .6% for bone-in to 68.0 +/- .7% for a completely boneless retail product. Correspondingly, processing times increased from 126.1 +/- 5.4 s to 542.0 +/- 19.2 s for bone-in and boneless legs, respectively. For all subprimals, retail yield percentage tended to decrease and total processing time increase as cuts were fabricated to boneless or semi-boneless end points compared with a bone-in end point. Percentage retail yield did not differ (P > .05) among whole carcass, three-piece box, and subprimal marketing methods. Total processing time was shorter for subprimals (P < .05) than for the other two marketing methods.

Subprimal purchasing and merchandising decisions for pork: relationship to retail yield and fabrication time

Boxed pork was obtained to represent four different purchase specifications (different anatomical separation locations and[or] external fat trim levels) common in the pork industry to conduct a study of retail yields and labor requirements. Bone-in loins (n = 180), boneless loins (n = 94), and Boston butts (n = 148) were assigned randomly to fabrication styles within subprimals. When comparing cutting styles within subprimals, it was evident that cutting style affected percentage of retail yield and cutting time. When more bone-in cuts were prepared from bone-in loin subprimals, retail yields ranged from 92.80 +/- .61 to 95.28 +/- .45%, and processing times ranged from 222.57 +/- 10.13 to 318.99 +/- 7.85 s, from the four suppliers. When more boneless cuts were prepared from bone-in loin subprimals, retail yields ranged from 71.12 +/- 1.10 to 77.92 +/- .77% and processing times ranged from 453.49 +/- 8.95 to 631.09 +/- 15.04 s from the different loins. Comparing boneless to bone-in cuts from bone-in loins resulted in lower yields and required greater processing times. Significant variations in yields and times were found within cutting styles. These differences seemed to have been the result of variation in supplier fat trim level and anatomical separation (primarily scribe length).

Subprimal purchasing and merchandising decisions for pork: relationship to retail value

To assess retail value and profitability, cutting test data were obtained in a simulated retail cutting room for boxed pork subprimals, bone-in loins (n = 180), boneless loins (n = 94), Boston butts (n = 148), fresh hams (n = 28), and boneless hams (n = 23). Processing times (seconds) and retail weights (kilograms) were used to determine relative value. Cutting style affected (P < .05) value differential (US$/subprimal) for bone-in and boneless loins. When cutting styles within subprimals were pooled, value differential was affected (P < .05) by purchasing specification for bone-in loins, boneless loins, Boston butts, and inside fresh hams. Processing bone-in loins to a boneless end point produced a greater (P < .05) value differential and percentage of gross margin than a bone-in retail end point. Bone-in loins fabricated to a boneless retail end point produced a greater (P < .05) value differential and percentage of gross margin than boneless loins fabricated to the same end point. The increase in retail value can be attributed to the increased number and weight of retail cuts produced from bone-in loins. The thick, boneless loin cutting style produced a greater (P < .05) value differential and percentage of gross margin as a result of a lower (P < .05) cost of fabrication and increased value of retail cuts than the thin, boneless cutting style. In general, boneless pork cutting methods were more profitable than bone-in cutting methods regardless of subprimal.

National Beef Quality Audit: survey of producer-related defects and carcass quality and quantity attributes

To assess the then-current population of fed beef cattle for quality defects, the federally inspected beef steer and heifer slaughter in 28 packing plants was surveyed during a 3-mo period (October to December 1991). Data were collected over the course of 1 d of production at chain speed. Carcasses were selected randomly to include 50 and 10% of each lot on the slaughter floor and in the cooler, respectively. Slaughter floor defects evaluated were brand location and size, degree of bruising, grubs and injection sites, condemnation of offal, and the presence of mud and horns. USDA grade factors and other data were collected in the cooler. The distribution of hot-iron brand scars on the hide for the sample was as follows: cattle with no brand, 55.0%; cattle with butt brands, 29.9%; cattle with side brands, 13.8%; and cattle with shoulder brands, .8%. In addition, 83.3, 85.6, 76.6, 97.3, 99.9, and 99.8% of the carcasses had no superficial bruising in the chuck, rib, loin, round, brisket, and other areas of the carcass, respectively. The incidence of viscera condemnations for livers, lungs, tripe, and total viscera were 19.2, 5.1, 3.5, and .1%, respectively. Means for the carcass traits were as follows: USDA yield grade, 3.1; hot carcass weight, 344.7 kg; adjusted fat thickness, 1.5 cm; longissimus muscle area, 83.4 cm2; kidney, pelvic, and heart fat, 2.2%; USDA quality grade, high Select; marbling score, Small-minus; and overall maturity, A69.

Estimates of subprimal yields from beef carcasses as affected by USDA grades, subcutaneous fat trim level, and carcass sex class and type

One hundred beef carcasses were selected to represent the mix of cattle slaughtered across the United States. Selection criteria included breed type (60% British/continental European, 20% Bos indicus, and 20% dairy carcasses), sex class (beef and Bos indicus: 67% steers, 33% heifers; dairy: 100% steers), USDA quality grade (4% Prime, 53% Choice, and 43% Select), USDA yield grade (10% YG 1, 43% YG 2, 40% YG 3, and 7% YG 4), and carcass weight (steers: 272.2 to 385.6 kg, heifers: 226.8 to 340.2 kg). One side of each carcass was fabricated into boneless subprimals and minor cuts following Institutional Meat Purchase Specifications. After fabrication, subprimals were trimmed progressively of fat in .64-cm increments beginning with a maximum of 2.54 cm and ending with .64 cm. Linear regression models were developed for each individual cut, including fabrication byproduct items (bone, fat trim) to estimate the percentage yield of those cuts reported by USDA Market News. Strip loin, top sirloin butt, and gooseneck rounds from heifers tended to have a higher percentage yield at the same USDA yield grade than the same cuts from steers, possibly resulting from increased fat deposition on heifers. Percentage of fat trimmed from dairy steers was 2 to 3% lower than that from other sex-class/carcass types; however, due to increased percentage of bone and less muscle, dairy steers were lower-yielding. Fat trimmed from carcasses ranged from 7.9 to 15.6% as the maximum trim level decreased from 2.54 to .64 cm.

National beef tenderness survey

To determine the average tenderness and sensory ratings of beef subprimal cuts sold in retail cases across the United States, retail cuts were purchased through typical retail outlets in 14 metropolitan cities and transported to Texas A&M University for sensory and Warner-Bratzler shear analysis. The overall mean shear force for all cuts was 3.65 kg, and the mean shear force values for chuck, rib, loin, and round cuts were 3.72, 3.36, 3.17, and 4.31 kg, respectively. No difference (P greater than .05) in tenderness was detected among the cuts from the rib. Mean palatability ratings and shear force values of top loin steaks were similar to those of rib cuts. Top sirloin steaks were tougher (P less than .05) and received the lowest sensory ratings compared with other loin cuts. Approximately two to three times as many round and chuck steaks had shear force values in excess of 4.6 kg compared with their roast counterparts. In all cases, roasts tended to be more tender than steaks from the same subprimal source. USDA Choice chuck retail cuts, compared to Select and No-roll chuck cuts, had approximately 10% fewer cuts with shear force values in excess of 4.0 kg. More work is needed to improve meat tenderness, primarily for retail cuts from the round and chuck primals. Future research must investigate the interaction of antemortem and postmortem factors associated with variation in beef tenderness.

Paradoxical effects of tumour necrosis factor in experimental ovarian cancer

Recombinant human tumour necrosis factor (rhTNF) had anti-tumour activity against 2 of 3 human ovarian cancer xenografts growing intraperitoneally (i.p.) in nude mice, producing a moderate (2- to 3-fold) increase in mouse survival time. rhTNF therapy caused a marked influx of polymorphonuclear neutrophils into the peritoneal cavity during the first few days of daily therapy. This was accompanied by a decrease in the number of peritoneal macrophages and lymphocytes. rhTNF also caused an increase in peripheral blood neutrophils. With continuation of daily therapy, the peritoneal neutrophil influx diminished, with restoration of the macrophage and lymphocyte populations. After 2 to 3 weeks there was a small but significant increase in peritoneal Thy 1.2+ cells. In the peripheral blood, the neutrophilia was less marked than at the start of therapy. Mild myelosuppression was indicated by significant falls in haemoglobin and platelet counts. Within 24 hr of the start of therapy in the 2 responsive xenografts (HU and LA) tumour clumps in the peritoneum were surrounded by host inflammatory cells, and tumours fixed to the omentum were infiltrated by neutrophils and mononuclear cells. In both instances necrosis was evident by 4 to 7 days. The third xenograft (OS) grew although the rhTNF therapy induced the same inflammatory changes in the peritoneum. In contrast to its positive effect on the survival of tumour-bearing mice, rhTNF promoted the adhesion of tumour cells to the peritoneum and their establishment as tumour nodules below the mesothelial surface. This phenomenon was seen in all 3 xenografts including the OS xenograft which did not respond in any other way to rhTNF therapy.

Interferons alpha and gamma differ in their ability to cause tumour stasis and regression in vivo

We have studied the antitumour activity of human lymphoblastoid interferon-alpha [HuIFN-alpha(N)] and human recombinant interferon-gamma (rHuIFN-gamma) on 12 early passage (passages 2-7) human tumour xenografts derived from primary malignancies. Systemic daily therapy of established (approx. 0.5 cm diameter) subcutaneous xenografts with HuIFN-alpha(N) resulted in significant tumour stasis, and occasionally regression, in nine of 12 breast, bowel, and ovarian cancers studied. A significant decrease in tumour mitotic index was seen in three HuIFN-alpha(N) sensitive breast tumours. In contrast, none of nine of the same tumours responded significantly to rHuIFN-gamma therapy. Direct administration of rHuIFN-gamma into the tumour did not improve its therapeutic efficacy. However, when tumour cells from xenografts were dissociated and grown as colonies in soft agar, both IFNs, used at doses that are found circulating in vivo after therapy, inhibited colony development in three of three lines tested. Combinations of rHuIFN-gamma and HuIFN-alpha(N) had no synergistic benefit in four of four xenografts studied.

Microflora of Vacuum Packaged Beef Steaks and Roasts Treated with an Edible Acetylated Monoglyceride

Steaks and roasts were fabricated from strip loins and top rounds that were held vacuum packaged for 10 d at 2°C. Steaks and roasts then were treated with 2-3% Dermatex^R Food Grade (DFG), an acetylated monoglyceride, vacuum packaged and stored at 2 ± 2°C for up to 4 weeks (steaks) and 7 weeks (roasts). Aerobic plate counts (APC) and APT counts of control and DFG-treated steaks and roasts did not differ (P>0.05) during refrigerated storage. The microflora of steaks and roasts during storage was dominated by lactic acid bacteria. Treatment with DFG did not influence the microbiological characteristics of the steaks and roasts.