Pork muscle profiling: pH and instrumental color of the longissimus thoracis is not representative of pH and instrumental color of shoulder and ham muscles

From a population of 351 pork carcasses, 3.0-cm thick chops from the 10th rib location of the longissimus thoracis, faced surfaces of the triceps brachii and serratus ventralis muscles from the boneless shoulder, and faced surfaces of the biceps femoris, semitendinosus, semimembranosus, adductor, rectus femoris, and vastus lateralis muscles from the boneless ham were evaluated for pH and instrumental color (Minolta CR-400). Evaluations were conducted for at least three different locations on each of the muscle samples and averaged before data analysis occurred. The longissimus thoracis had the lowest pH and the lightest and least red color compared with the other eight muscles evaluated in this study (mean differences ranged from 0.98 to 8.70 for L*, 3.98 to 12.56 for a*, and 0.026 to 0.409 for pH). Furthermore, regression analysis suggested that pH and color values for the longissimus thoracis were not adequate predictors for pH and color values obtained from other muscles and therefore consideration should be given to the individual muscles that are of interest.

Technical note: An update of the predicted lean yield equation for the Destron PG-100 optical grading probe

The objective was to update the equation used for prediction of pork carcass leanness with the Destron PG-100 optical grading probe. A recent cutout study (completed in 2020-2021) consisting of 337 pork carcasses was used for this research. An updated equation was generated using a calibration dataset (n = 188 carcasses) and prediction precision and prediction accuracy of the new equation was evaluated using a validation dataset (n = 149 carcasses). The updated equation was generated using forward stepwise selection multiple regression techniques in PROC REG of SAS, and the same parameters as the existing equation were used to fit the model. The updated Destron equation [89.16298 - (1.63023 × backfat thickness) - (0.42126 × muscle depth) + (0.01930 × backfat thickness2) + (0.00308 × muscle depth2) + (0.00369 × backfat thickness × muscle depth)] and the existing Destron equation [68.1863 - (0.7833 × backfat thickness) + (0.0689 × muscle depth) + (0.0080 × backfat thickness2) - (0.0002 × muscle depth2) + (0.0006 × backfat thickness × muscle depth)] were similar in their prediction precision for determination of carcass lean yield (LY), with the updated equation R 2 = 0.75 and root mean square error (RMSE) = 1.97 and the existing equation R 2 = 0.75 and RMSE = 1.94. However, when prediction accuracy was evaluated using the variance explained by predictive models based on cross-validation (VEcv) and Legates and McCabe's efficiency coefficient (E1), the updated equation (VEcv = 67.97%; E1 = 42.41%) was much more accurate compared with the existing equation (VEcv = -117.53%; E1 = -69.24%). Furthermore, when accuracy was evaluated by separating carcasses into 3% carcass LY groupings ranging from less than 50% LY to greater than 62% LY, the existing equation correctly estimated carcass LY 8.1% of the time, while the updated equation correctly estimated carcass LY 47.7% of the time. In an effort to further compare the abilities of the updated equation, comparisons were made with an advanced automated ultrasonic scanner (AutoFom III), which scans the entire carcass. The prediction precision of the AutoFom III was R 2 = 0.83 and RMSE = 1.61, while the AutoFom III correctly estimated carcass LY 38.2% of the time and prediction accuracy calculations for the AutoFom III were VEcv = 44.37% and E1 = 21.34%). Overall, refinement of the Destron PG-100 predicted LY equation did not change prediction precision, but substantially improved prediction accuracy.

Sous Vide Cook Temperature Alters the Physical Structure and Lipid Bioaccessibility of Beef Longissimus Muscle in TIM-1

Changes in the physical states, induced with different sous vide cooking temperatures, significantly (P < 0.05) altered lipid bioaccessibility measured in the TNO-simulated gastrointestinal tract model-1 of AAA boneless beef striploin, containing the longissimus lumborum muscle. The denaturation of actin significantly correlates with the total cumulative free fatty acid (FFA) bioaccessibility, whereby the striploin cooked to 60 °C presents the maximum lipid bioaccessibility (15.8 ± 1.0%), rate constant (k_a) for FFA hydrolysis (0.087 ± 0.003 min^-1), and greatest actin denaturation enthalpy (-0.57 ± 0.06 ΔH). Thus, thermal treatments above 60 °C significantly decrease the kinetics of lipolysis (70 °C = 0.042 ± 0.002 min^-1 and 80 °C = 0.047 ± 0.002 min^-1) and the resultant total lipid bioaccessibility (70 °C = 8.6 ± 0.7 and 80 °C = 8.3 ± 0.5%). This research highlights the potential to manipulate the physical food structure to alter digestion kinetics, supporting the need to understand supramolecular structures in food and their nutritional outcomes.

Effects of Replacing Antibiotics in Finishing Cattle Diets with Plant-Based Additives on Meat Quality and Sensory Attributes

ObjectivesLimited research has investigated the effects of plant-based additives fed to feedlot cattle beyond cattle growth performance and carcass characteristics. Thus, the objective of this study was to investigate the effects of feeding antibiotic supplements versus essential oils and/or benzoic acid to finishing cattle on meat quality and sensory attributes of the longissimus thoracis (LT) muscle.Materials and MethodsCrossbred steers (N = 63) were placed into 3 blocks based on initial weight. Within each block, 1 of 5 treatments were randomly applied using an Insentec feeding system for 98 d: (1) control (CON) diet (no supplement); (2) monensin/tylosin (M/T) diet (monensin supplemented at 33 mg/kg on dry matter (DM) basis; tylosin supplemented at 11 mg/kg on DM basis); (3) essential oils (EO) diet (supplemented at 1.0 g/steer/day); (4) benzoic acid (BA) diet (supplemented at 0.5% on DM basis); and (5) combination (COMBO) diet (essential oils supplemented at 1.0 g/steer/day and benzoic acid supplemented at 0.5% on DM basis). Beef rib (IMPS#107) sections from the right side of carcasses were collected from a commercial processing facility and transported to the U of Guelph meat science laboratory and processed into 2.54 cm LT steaks. pH and objective color were collected for the LT steaks at 6 d post-mortem. Samples for cooking loss and shear force were aged for 7 d and 14 d post-mortem. Samples for sensory were aged for 7 d post-mortem. Duplicate 5 to 6 g homogeneously blended LT samples were analyzed for moisture content by forced-air convection oven drying at 100°C for 24 h (Method 950.46, AOAC. Lipid content of the dried samples were determined by Soxhlet extraction with petroleum ether, followed by 24 h of oven drying at 100°C. Cooking loss was measured after cooking samples to an internal temperature of 72°C. Warner-Bratzler shear force (WBSF) was measured on 1.3 cm diameter cores that were cut parallel to muscle fibers. Meat quality results were analyzed as a randomized complete block design (RCBD) with fixed effects of treatment, block and their interaction using PROC GLIMMIX of SAS. For sensory analysis, 8 highly trained panelists evaluated the tenderness, juiciness, chewiness, beef flavor intensity, and off-flavor intensity of steaks using a 15-cm line scale. Each steak was cooked to 68°C and served to each panelist as two 1-cm cubes. Results were analyzed as a RCBD with the fixed effects of treatment, panelist, and their interaction and the random effect of session.ResultsThere were no significant differences (P > 0.07) among treatments in this study for pH, objective color, % moisture, WBSF, or cooking loss of LT samples. Ribeye from the CON diet had significantly less % crude fat (P = 0.05) compared to other treatments. There was an effect of diet on the tenderness, chewiness, juiciness and beef flavor intensity of steaks as determined by the panelist. Specifically, CON and COMBO steaks were tougher, chewier and less juicy. All steaks had strong beef flavor, especially the BA steaks. Off-flavors were barely detectable.ConclusionResults showed that EO and BA when fed to finishing cattle do not affect meat quality. Trained panelists reported steaks in the M/T, EO, and BA diet were tender, juicier, and had stronger beef flavors. Potential off-flavors and off-aromas in finishing feed did not translate to beef products.

Processing Characteristics and Sensory Attributes of Bacon Manufactured From Seven Value-Added Cuts of Beef

ObjectivesThere is great opportunity for the beef industry to add value to cuts that are currently marketed as low value cuts (i.e., cuts from the chuck, round, and flank/plate). The objective was to evaluate the processing characteristics and sensory attributes of bacon manufactured from seven different cuts of beef.Materials and MethodsThe seven cuts evaluated included the brisket (IMPS#120), the clod heart (IMPS#114E; divided horizontally into two halves; referenced as the wide half or silverskin side and the narrow half or non-silverskin side), the flank (IMPS#193), the outside flat (IMPS#171B), and the short plate (IMPS#121A; broken down into the deboned short rib half and the navel half). The cuts were injected using a standard commercial bacon cure (water, salt, corn syrup solids, sodium phosphate, sodium erythorbate, sodium nitrate, sodium bicarbonate, and glycerin; Herman Laue Spice Company Inc.; Uxbridge, Ontario, Canada) to a targeted rested pump uptake of approximately 20% (± 3%). The injected cuts were cooked to an internal temperature of 62°C in a smokehouse (ScottPec, Guelph, Ontario). Following cooking, cuts were cooled to 4°C and then sliced into 4.0 mm slices using a deli slicer. Slices were vacuum packaged, boxed, and stored at 4°C for zero, thirty, sixty, or ninety days. Following the allotted storage period, slices were stored at –20°C until evaluation of sensory attributes and cooking loss. Slices were cooked at 204°C for 15 min in a convection oven. Processing characteristics were conducted in six or seven replications for each cut. Sensory evaluation was conducted on three randomly selected samples for each cut at each of the four storage times (the same samples within each cut was used at each storage time). Processing data were analyzed using PROC GLIMMIX of SAS (v9.4) with fixed effect of cut and random effect of replication. A trained descriptive sensory panel of 6–8 panelists evaluated the differences in oxidative flavor and aroma (using a 4-pt nominal scale), and differences in beef flavor intensity, muscle fiber toughness, and connective tissue amount (using magnitude estimation). Sensory data were analyzed as repeated measures using PROC GLIMMIX of SAS (v9.4) with fixed effect of cut, storage day, and their interaction, and random effects of session, panelist, and replication.ResultsAs expected, dimensions and processing weights differed (P < 0.01) among cuts. Rested pump uptake was not different (P = 0.29) among cuts. Smokehouse yield was greater (P < 0.05) for the brisket, outside flat, and short plate (both halves) compared with the clod heart (both halves) and flank. Bacon slice cooking loss and sensory characteristics are presented in Table 4.ConclusionOverall, this research indicated that a variety of beef cuts can be used to manufacture beef bacon. The differences in sensory properties that were quantified in this study, allow manufacturers to tailor their cut selection to the sensory properties most valued by their consumers. All cuts exhibited oxidative stability when stored up to 90 d.Table 4Bacon slice cooking loss and sensory analysis of bacon manufactured with different beef cuts. Main effects of cut after 0, 30, 60, and 90 d of storage

The Effect of Breadfruit (Artocarpus altilis) Flour on Color of Comminuted Beef Compared with Other Flour Sources

ObjectivesNovel, non-allergenic ingredients with properties that improve the quality of processed meat products are needed for the meat industry. The objectives of this study were to investigate the effect of breadfruit (Artocarpus altilis) flour on color of comminuted beef compared with other flour sources.Materials and MethodsFlour sources included breadfruit, corn, soy, tapioca, and wheat. All flours were obtained commercially and were unmodified. Lean beef (from the same commercially sourced batch targeted to 90% lean and 10% fat), 10% ice, 1.5% salt, and flour sources at two inclusion levels (2.5% and 5%) were mixed using a bowl chopper to prepare beef patties for evaluation. The ground beef was manufactured into 115 g patties that were placed on a retail display shelf under continuous LED lighting at 4°C for 7 d. Lighting was measured periodically during the study and LUX was ensured to be between 1612.5 lux and 2152.0 lux. Objective CIE L* (lightness), a* (redness), and b* (yellowness), chroma, and hue scores were collected with a Minolta CR-400 Chroma meter (Konica Minolta Sensing, Inc., Osaka, Japan) utilizing a D65 light source and a 0° observer with an aperture size of 8 mm on each day of the simulated retail display. This study was conducted in three independent replicates for each treatment. Statistical analyses for parameters (L*, a*, b*, chroma, and hue) were conducted using the MIXED procedure of SAS with fixed effects of flour source*inclusion level, day, and their interaction. Least square means were separated using the PDIFF option with a Tukey-Kramer adjustment. Differences were considered statistically different at P < 0.05.ResultsThe interaction of storage day and treatment significantly (P ≤ 0.001) affected a*, b*, chroma, and hue. There was not an interaction of storage day and treatment for L*. Both the main effect of storage day and the main effect of treatment significantly (P < 0.01) affected all the attributes measured in this study. Mean L* over the display period of beef patties prepared with 2.5% breadfruit flour were not different (P = 0.95) compared with control samples. There was no significant difference between the mean hue over the 7-d display period of the beef patties prepared with 2.5% breadfruit flour compared with control samples. a* decreased at different rates for each treatment throughout the display period. Beef patties prepared with 2.5% and 5% breadfruit flour were redder (greater a*; (P < 0.05)) compared with other treatments and control samples over the 7-d display period. To the contrary, a* values of beef patties prepared with soy flour were less than (P < 0.05) other treatments and the control samples on Day 0 and Day 1 and remained constant at lower values as the display period increased.ConclusionBreadfruit flour improved the redness of comminuted beef products immediately and prevented discoloration for a longer period. The results indicate that breadfruit flour can effectively improve initial color and stability of color in processed beef products. More research is warranted to further investigate the mechanism of action of breadfruit flour in governing the color properties of comminuted beef products.

Relationship Between Carcass Weight, Muscle, Fat, and Predicted Lean Yield for Commercial Pigs in Ontario

ObjectivesGreater knowledge of variance and relationships of pork carcass parameters could be used to improve performance, efficiency, and profitability of the pork industry. Previous research has investigated the correlation between pork carcass parameters; however, there are still many misunderstandings, particularly in commercially representative pigs. Thus, the purpose of this study was to examine the correlation and variance of carcass weight, fat depth, muscle depth, and predicted lean yield in commercial pigs.Materials and MethodsThe second largest commercial pig slaughter facility in Ontario slaughtered approximately 1.5 million pigs in 2018. Carcass data (hot carcass weight, fat depth, muscle depth, and predicted lean yield) from 1025,572 pigs was used for this study with pigs slaughtered on each production day of 2018 (between January 2, 2018 and December 31, 2018). Hot carcass weight was reported immediately following slaughter as a head-on weight, and fat depth and muscle depth were measured with a Destron PG-100 probe (International Destron Technologies, Markham, Ontario). The equation used for predicted lean yield was the Canadian Lean Yield equation (CLY (%) = 68.1863– (0.7833 × fat depth) + (0.0689 × muscle depth) + (0.0080 × fat depth2) – (0.0002 × muscle depth2) + (0.0006 × fat depth × muscle depth). Pearson product moment correlation coefficients were calculated among all parameters using RStudio version 1.1.456 and R version 3.5.1 statistical software. Correlation coefficients were considered significantly different from 0 at P < 0.05. Correlations were considered weak (in absolute value) for r < 0.35, moderate for 0.36 ≤ r ≤ 0.67, and strong for r ≥ 0.68. Linear regression models were created between parameters that had meaningful relationships using the RStudio statistical software. Gnuplot version 5.2 was used to create scatter plots to allow for better visualization of the correlation between meaningful parameters.ResultsThe mean ± standard deviation for fat depth, muscle depth, hot carcass weight, and predicted lean yield were 18.27 ± 4.12 mm, 65.69 ± 9.06 mm, 105.93 ± 8.39 kg, and 61.03 ± 1.91%, respectively. We observed weak positive correlations between fat depth and hot carcass weight (r = 0.27; P < 0.0001), and between muscle depth and hot carcass weight (r = 0.17; P < 0.0001). We obtained a weak negative correlation between predicted lean yield and hot carcass weight (r = –0.21; P < 0.0001). The predicted lean yield equation used for this set of pigs included measurements for fat depth and muscle depth, so strong correlation between these parameters was expected. We obtained a moderate positive correlation between muscle depth and predicted lean yield (r = 0.39; P < 0.0001) and a strong negative correlation between fat depth and predicted lean yield (r = –0.96; P < 0.0001).ConclusionResults from this dataset revealed that hot carcass weight was generally not correlated with fat depth, muscle depth, or predicted lean yield. The conclusion of this study based on the current dataset is that pigs do not reach a weight threshold where they consistently become fatter or heavier muscled.

Technological Properties of Beef Emulsions Prepared with a Novel Processed Potato Ingredient (O’Brien’s Best)

ObjectivesThe processed potato ingredient tested in this study was a commercially available ingredient (O’Brien’s Best; Botaniline Foods, LLC) that consists of skinned, sliced potatoes that were cooked to an exact time/temperature to enhance physiochemical properties. The objective of the study was to assess the technological properties of beef emulsion modeling systems prepared with the novel processed potato ingredient (O’Brien’s Best).Materials and MethodsThe meat used in this study was lean ground beef from one master batch of beef that was targeted to 90% lean and 10% fat. The meat batter formulations contained 20% water, 6.15% spice/seasoning, 0.18% Prague powder, and 0.0035% sodium erythorbate, and varying quantities of sodium tri-polyphosphate, salt (NaCl), and binders (processed potato, tapioca starch, or all-purpose binder). In total, eight treatments were formulated and manufactured on three separate, independent occasions (N = 24 experimental units; n = 3 replications). Three treatments were formulated with the novel processed potato ingredient (formulated without phosphate, 0.635% NaCl, and either 5, 10, or 15% the processed potato ingredient). Three treatments were formulated with commercially sourced tapioca starch (formulated without phosphate, 0.635% NaCl, and either 5, 10, or 15% commercial tapioca starch, which was tested to be 78% starch purity). Two treatments were formulated with a commercial formulation [formulated with 0.30% sodium tri-polyphosphate, 10% all-purpose binder (a multi-ingredient proprietary blend binder from Herman Laue Spice Company Inc.; Uxbridge, Ontario), and 1.905% NaCl, or 1.270% NaCl]. Parameters tested were cooking loss, proximate composition of cooked meat batters, texture profile analysis of cooked meat batters, and instrumental color of uncooked and cooked meat batters. Data were analyzed with the GLIMMIX procedure of SAS v9.4 with a fixed effect of treatment and a random effect of replication. Least square means were separated using the PDIFF option with a Tukey-Kramer adjustment. Differences were considered statistically different at P < 0.05.ResultsCooking loss was not different (P = 0.44) among treatments and ranged from 0.64% to 0.77%, indicating acceptable stability for all emulsion formulations in the study. Proximate composition revealed significant differences (P < 0.05) in moisture, protein, ash, and other components (carbohydrates), while lipid content was unaffected. Texture profile analysis revealed that textural properties were generally unaffected (P > 0.05) by treatment, with the exception of less gumminess (P < 0.05) and less chewiness (P < 0.05) in processed potato formulated emulsions compared with the tapioca starch and commercially formulated emulsions. Instrumental color of uncooked emulsions was affected to a greater degree than instrumental color of cooked emulsions. Yet, when tapioca starch was included at high levels (> 10%) in cooked emulsions lightness (L*) and yellowness (b*) were greater (P < 0.05) compared with emulsions formulated with the processed potato ingredient and with the commercial formulations.ConclusionIn summary, the technological properties (cooking loss, texture profile analysis, and instrumental color) of beef emulsion systems were largely unaffected by the processed potato ingredient (despite removal of phosphates and less NaCl) and performed similar to the commercial formulations.

The Effect of Specialty Salts on Cooking Loss, Texture Properties, and Instrumental Color of Beef Emulsion Modeling Systems

ObjectivesSalt plays an integral role in meat processing, and reduction or exclusion will have negative impacts on water holding capacity and binding function of protein and fat. Specific to meat emulsions, NaCl is used in the formulation due to its effect on the solubilization (extraction) of myofibrillar meat proteins, which allow the formation and stabilization of the interfacial matrix during manufacture and preparation. While previous research has addressed preservation (shelf-life and oxidation attributes) and flavor (sensory attributes) when using specialty salts in meat products, the application of specialty salts in meat emulsions has never been addressed in a scientific manner. Therefore, the purpose here was to evaluate the incorporation of different levels and types of specialty salts on the physicochemical and textural characteristics of beef emulsions.Materials and MethodsThree specialty NaCl salts (premium sea salt, pink sea salt, and gray sea salt) were added to beef emulsion modeling systems at three different inclusion levels (0.70, 1.00, and 1.30%) and then compared with commercially sourced white salt. Salt (NaCl) purity levels for commercially sourced white salt, premium sea salt, pink sea salt, and gray sea salt were 99.8, 99.8, 95.2, and 94.9%, respectively. Cooking loss, emulsion stability, proximate composition, pH, texture profile analysis, and instrumental color of the emulsions were evaluated with three independent replications from one batch of ground beef. One batch of ground beef was used to properly control for confounding factors such as beef source and day of manufacture. Treatment was applied to one of twelve 500-g base emulsions (without artificial food dyes, preservatives, spices, and seasonings) containing beef (according to the level of salt added), water (28.14%), oil (8.00%), starch (2.00%), and phosphate (0.35%) for each replication (36 total experimental units). Data were analyzed with PROC GLIMMIX of SAS with fixed effects of salt type, salt inclusion level, and their interaction, and the random effect of replication. Least square means were separated using the PDIFF option with a Tukey-Kramer adjustment, and was further separated using an orthogonal set of estimate statements to analyze linear and quadratic effects for salt inclusion level. Differences were considered different at P ≤ 0.05.ResultsEmulsion stability and cooking loss were primarily affected (P < 0.01) by salt inclusion level rather than salt type (P ≥ 0.13). Stability increased and cooking loss decreased as salt inclusion level increased (linear P < 0.01). Proximate composition of cooked meat emulsions trended differently as salt increased from 0.70% to 1.30% salt inclusion level for the different salt types. Moisture increased and lipid decreased for commercial white salt, while moisture decreased, and lipid increased for all three of the specialty salts. Hardness, springiness, gumminess, and chewiness of emulsions increased as the level of salt increased for all the treatments and were greatest (P < 0.0001) in all treatments at the 1.30% salt inclusion level, however, no differences were observed between the salt types.ConclusionOverall, salt inclusion level, rather than salt type, had significant effects on the solubilization of protein and dispersion interactions of the emulsions, which affected physicochemical and functional properties.

Correlation Among Ground Beef Lipid Content, Color, and Lipid Oxidation Over a 7-Day Simulated Retail Display Period

ObjectivesGround beef is more susceptible to lipid oxidation compared to whole muscle beef cuts. This is due to its smaller particle size and greater surface area, which makes the meat products more prone to be exposed to various environmental factors during production. The objective of this study was to determine the relationships among ground beef lipid content, instrumental color, visual discoloration, and lipid oxidation over a 7d simulated retail display period.Materials and MethodsBeef inside rounds (IMPS #168) from the right sides of steer carcasses (n = 63) were collected from a commercial processing facility and delivered to the U of Guelph Meat Science Laboratory for further analyses. Each inside round was trimmed of all subcutaneous fat and connective tissue, and then fabricated into ground beef patties (113 g/patty) at two targeted fat addition levels (no added fat and 25%). Lean ground beef (no added fat) was made by grinding cubes of inside round muscle through a Sirman Master 90 Y12 meat grinder (Sirman USA, Franklin Park, IL). Regular ground beef (25% added fat) was made by grinding cubed round muscle with an additional 25% subcutaneous fat that originated from the rib primal of the same carcass. For the simulated retail shelf life study, 2 crust frozen patties (crust frozen for 1 h to improve packaging ability) were placed on a Styrofoam meat tray with a soaker pad and overwrapped with PVC film. In total, there were 4 trays of patties per ID (2 trays/targeted fat level). Trays were placed under two LED lights (52 W, 1850 lumens, color temperature of 4000K, 1612.5 to 2152 lux) at 4°C and the locations on shelves were changed every 24 h. Minolta L*, a*, b* color and subjective surface discoloration were evaluated every 24 h for 7 d. Lipid peroxidation of patties before and after the retail display was estimated using thiobarbituric reactive substances (TBARS; mg MDA/g fat). Lipid content of patties was quantified using Soxhlet extraction with petroleum ether. Summary statistics and Pearson correlation coefficients were determined using the PROC CORR procedure of SAS. Correlations were regarded as weak at r < |0.35|, moderate at |0.36| ≤ r ≤ |0.67|, and strong at r ≥ |0.68|.ResultsLipid content in the 126 ground beef samples evaluated in this study ranged from 3.47% to 30.43% (16.30% ± 6.18%). A moderate and significant correlation was observed between lipid content and change in TBARS values (r = –0.59, P < 0.0001). Similarly, an increase in lipid content is moderately correlated with a decrease in a* values (r = –0.58, P < 0.0001) and an increase in surface discoloration after a 7d display period (r = 0.53, P < 0.0001). Δ TBARS values was weakly correlated with Δ L* (r = 0.24, P < 0.01), Δ a* (r = 0.11, P = 0.25), and visual discoloration (r = –0.16, P = 0.09). Finally, Δ a* was strongly correlated with surface discoloration values at d7 (r = –0.76, P < 0.0001).ConclusionAn increase of lipid content in ground beef had a moderate association with decreased redness, greater surface discoloration, and less change in lipid oxidation over a 7d simulated retail display period. Color values were not great predictors of lipid oxidation values and trained technicians often equated visual discoloration in beef to a deviation from the desired cherry red color.

A comprehensive perspective of food nanomaterials

Nanotechnology is a rapidly developing toolbox that provides solutions to numerous challenges in the food industry and meet public demands for healthier and safer food products. The diversity of nanostructures and their vast, tunable functionality drives their inclusion in food products and packaging materials to improve their nutritional quality through bioactive fortification and probiotics encapsulation, enhance their safety due to their antimicrobial and sensing capabilities and confer novel sensorial properties. In this food nanotechnology state-of-the-art communication, matrix materials with particular focus on food-grade components, existing and novel production techniques, and current and potential applications in the fields of food quality, safety and preservation, nutrient bioaccessibility and digestibility will be detailed. Additionally, a thorough analysis of potential strategies to assess the safety of these novel nanostructures is presented.

Growth performance, carcass quality, fresh belly characteristics, and commercial bacon slicing yields of growing-finishing pigs fed a subtherapeutic dose of an antibiotic, a natural antimicrobial, or not fed an antibiotic or antimicrobial

The objective was to compare growth performance, belly characteristics, and bacon slicing yields of growing-finishing pigs fed a subtherapeutic dose of an antibiotic, a natural antimicrobial, or a diet containing no antibiotics or antimicrobials. Barrows and gilts (96 each, initial BW: 27.52±3.98kg) were housed in 48 pens (8 replications per treatment) in a 2×3 factorial randomized complete block design. Pens were assigned 1 of 3 diets: antibiotic free, oregano or tylosin phosphate. Pigs were slaughtered at an average BW of 127.31±10.18kg. There were no differences among dietary treatments for growth performance (P≥0.06), carcass cutability (P≥0.42), loin quality (P≥0.28), fresh belly dimensional characteristics (P≥0.11), IV (P≥0.87) or bacon processing characteristics (P≥0.07). Given the lack of differences in meat quality from pigs fed diets without antibiotics, the implementation of VFD in the United States should not result in changes in pork quality.

A comparison of intact and degraded desmin in cooked and uncooked pork longissimus thoracis and their relationship to pork quality

The objective was to compare desmin abundance (intact, degraded, and the ratio of intact desmin to degraded desmin) in samples from cooked and uncooked pork and establish its relationship to pork quality traits. Pork chops (2.54-cm thick) from twenty-four pork loins were randomly assigned to treatment (cooked or uncooked). Intact and degraded desmin in cooked and uncooked chops aged 1d were weakly correlated (r<|0.35|) with Warner-Bratzler shear force at 1 and 14d postmortem aging. Intact and degraded desmin in cooked and uncooked chops aged 14d were moderately correlated (|0.35|<r<|0.59|) with Warner-Bratzler shear force at 1 and 14d postmortem aging. Intact:degraded desmin in cooked and uncooked pork aged 1 and 14d was generally weakly correlated (r<|0.35|) with pork quality traits, with only a few exceptions. This research supports previous reports that the same sample can be used for tenderness of cooked pork and the determination of desmin abundance.

Effects of marketing group on the quality of fresh and cured hams sourced from a commercial processing facility

The objective was: 1) to characterize the effect of marketing group on fresh and cured ham quality, and 2) to determine which fresh ham traits correlated to cured ham quality traits. Pigs raised in 8 barns representing 2 seasons (hot and cold) and 2 production focuses (lean and quality) were used. Three groups were marketed from each barn. A total of 7,684 carcasses were used for data collection at the abattoir. Every tenth carcass was noted as a select carcass for in-depth ham quality analyses. Leg primal weight and instrumental color were measured on 100% of the population. On the select 10% of the population, hams were fabricated into sub-primal pieces, and 3-piece hams were manufactured to evaluate cured ham quality and processing yield. Data were analyzed as a split-plot design in the MIXED procedure of SAS with production focus as the whole-plot factor, and marketing group as the split-plot factor. Pearson correlation coefficients between fresh and cured ham traits were computed. There were no differences ( ≥ 0.15) in instrumental color or ultimate pH ( ≥ 0.14) among fresh ham muscles from any marketing group. The only exception was the semimembranosus of marketing group 2 was lighter than marketing group 1 ( = 0.03) and the dark portion of the semitendinosus muscle from group 1 was lighter than from group 3 ( = 0.01). There were no differences ( ≥ 0.33) in ultimate pH of fresh ham muscles between production focuses, but several muscles from quality focus pigs were lighter in color than ham muscles from lean focus pigs. The lack of differences in fresh ham quality lead to few differences in cured ham quality. Cured hams from the quality focus pigs had greater lipid content ( < 0.01) than hams from lean focus pigs. Cured lightness values of hams from marketing group 1 and 2 were 1.52 units lighter than hams from marketing group 3 ( 0.01). Overall, marketing group did not impact ham quality. Fresh ham quality was not strongly related to cured ham quality. Some correlations were present between fresh and cured ham traits, but those relationships were likely not strong enough to be used as a sorting tool for fresh hams to generate high quality cured hams.

Effects of time after a second dose of immunization against GnRF (Improvest) independent of age at slaughter on commercial bacon slicing characteristics of immunologically castrated barrows

The objective was to determine the effects of time after a second dose of anti-GnRF immunization on fresh belly characteristics and slicing yields of immunologically castrated (IC) barrows, physically castrated (PC) barrows and gilts slaughtered at 24 weeks of age. The second dose was staggered so that IC barrows were slaughtered at 4, 6, 8, or 10 weeks after the second dose. Fresh belly characteristics (N=141) were collected at slaughter and bacon was manufactured commercially. The main effects in the model were treatment and the random effects of block and block within replication. Thickness, flop distance, and lipid content increased (L; P<0.04) and iodine value tended to decrease (L; P=0.08) with time after the second dose in IC barrows. Slicing yields increased with time after the second dose (L; P<0.01), but were similar (P=0.11) among sexes. Increasing time of slaughter after second anti-GnRF dose improves fresh belly and bacon slicing characteristics in IC barrows.

Effects of feeding canola meal from high-protein or conventional varieties of canola seeds on growth performance, carcass characteristics, and cutability of pigs

The objectives of this experiment were to determine growth performance, visceral mass differences, carcass characteristics, fresh meat quality, and carcass cutability of growing-finishing pigs fed diets containing high-protein canola meal (CM-HP) or conventional canola meal (CM-CV). Seven dietary treatments were fed to investigate effects of increasing inclusion rates of CM-HP or CM-CV in a corn-soybean meal diet containing no canola meal (control). Inclusion rates were 33, 66, or 100% replacement of soybean meal with either CM-HP or CM-CV. Pigs (140 barrows and 140 gilts; 2 barrows and 2 gilts per pen) were fed experimental diets in 3 phases with each phase lasting 35, 28, and 28 d, respectively. Within each phase, diets were formulated to be similar in concentrations of standardized ileal digestible indispensable AA and in standardized total tract digestible P, but NE concentrations were not equalized among diets. At the conclusion of the experiment, 1 pig per pen was harvested. Over the 91-d growing-finishing period, no effects of CM-HP on ADG, ADFI, or G:F were observed, but final BW tended ( = 0.06) to be reduced as increasing levels of CM-HP were included in the diets. There was a linear increase ( < 0.05) in ADFI and a linear reduction ( < 0.05) in G:F as CM-CV inclusion level increased. Pigs fed CM-CV also had greater ( < 0.05) ADG and ADFI than pigs fed diets containing CM-HP. There was a linear increase ( < 0.01) in liver weights, as a percentage of live weight, as CM-CV inclusion increased, but that was not the case if CM-HP was included in the diets. There was a linear increase ( < 0.05) in kidney weights, as a percentage of live weight, as CM-HP or CM-CV inclusion increased. There were no differences among treatments for ending live weight, HCW, carcass yield, loin eye area, 10th rib backfat thickness, or estimated carcass lean. Shear force, cook loss, LM moisture, LM extractible lipid, and drip loss were also not different among treatment groups. There were no differences among treatments for any subjective LM quality evaluations (color, marbling, firmness). Pigs fed CM-HP had increased ( < 0.05) boneless lean cutting yields and boneless carcass cutting yields compared with pigs fed CM-CV. In conclusion, CM-HP and CM-CV may fully replace soybean meal as protein supplements in growing-finishing pig diets without substantially impairing pig performance or carcass quality.

A comparison of slice characteristics and sensory characteristics of bacon from immunologically castrated barrows with bacon from physically castrated barrows, boars, and gilts

The objectives were to compare slice characteristics and sensory attributes of bacon from immunologically castrated (IC) barrows with bacon from other sexes using a trained sensory panel. Bacon was obtained for sensory evaluation from 3 experiments. In Exp. 1, trimmed and squared bellies (n=180) of IC barrows, IC barrows fed ractopamine hydrochloride (IC+RAC), physically castrated (PC) barrows, intact males (IM), and gilts were used. Data were analyzed as a general linear mixed model and pen (n=48) served as the experimental unit. Treatment (sex or diet) was a fixed effect in all 3 experiments. In Exp. 2, untrimmed, natural fall bellies (n=96) from IC and PC barrows fed 0 or 30% or a withdrawal distillers dried grains with solubles (DDGS) program when slaughtered at 5 wk after the second dose (25 wk of age) were used. In Exp. 3, untrimmed, natural fall bellies (n=96) from IC and PC barrows fed the same experimental diets as in experiment 2 but slaughtered at 7 wk after the second dose (27 wk of age) were used. Data from Exp. 2 and 3 were analyzed as a 2×3 factorial arrangement in a randomized complete block design and pen was the experimental unit. Bellies from all 3 experiments were processed using the same protocols. In Exp. 1, IM had the greatest (P<0.0001) boar aroma and flavor scores among all treatments. No differences were detected among the other treatment groups for boar aroma or flavor. Intact males had the least (P<0.0001) desirable cured bacon aroma and flavor among all treatments. No differences were detected among the other treatment groups for bacon aroma or flavor. There were no differences in bacon aroma or off-flavor between IC and PC barrows slaughtered at 5 wk after the second dose regardless of DDGS feeding program. Bacon from PC barrows was saltier (P<0.01) than bacon from IC barrows when slaughtered at 5 wk after the second dose. There were no differences in bacon aroma, off-aroma, bacon flavor, or saltiness between IC and PC barrows slaughtered at 7 wk after the second dose regardless of DDGS feeding program. Total slice area of bacon slices from IC barrows slaughtered at 5 wk after the second dose were less (P<0.01) than PC barrows, but the differences diminished (P=0.16) when slaughtered at 7 wk after the second dose. Overall, panelists successfully detected boar odor and flavor in Exp. 1. Immunological castration was as effective as physical castration at eliminating boar aroma and boar flavor in bacon even when feeding differing DDGS feeding programs or when slaughtered at 5 or 7 wk after the second dose.