Impact of beef carcass size on chilling rate, pH decline, display color, and tenderness of top round subprimals

Beef carcass weights in the United States have continued to increase over the past 30 yr. As reported by the United States Department of Agriculture, grid-based carcass weight discounts begin when carcasses exceed 408 kg. Despite weight discounts, beef carcass weights continue to increase. At the same time, an increased prevalence of discoloration and color variability in top round subprimals has been observed throughout the industry which may be influenced by the increases in carcass weights. The objectives of this study were to assess the effects of beef carcass size and its relationship to chill time, color, pH, and tenderness of the beef top round. In the current study, eight industry average weight beef carcasses (AW, 341–397 kg) and eight oversized beef carcasses (OW, exceeding 432 kg) were evaluated. Temperatures and pH measurements were observed on both sides of all carcasses for the initial 48 h postharvest at a consistent superficial and deep anatomical location of the respective top rounds. Carcasses were fabricated into subprimals at 48 h and top rounds were aged at 2 °C for an additional 12 d. The superficial location of both AW and OW carcasses cooled at a faster rate (P < 0.01) than the deep locations. The deep location of OW carcasses had a lower pH and a more rapid (P < 0.01) initial pH decline. Quantitative color of steaks from OW carcasses had greater mean L* (lightness; P = 0.01) and initial b* (yellowness; P < 0.01) values. The delayed temperature decline and the accelerated pH decline of the deep location of the top round of OW carcasses occur at different rates than AW carcasses. Delayed rate of cooling leads to irreversible impacts on steak appearance of top round steaks fabricated from OW beef carcasses when compared with AW carcasses.

Dry potato extracts improve water holding capacity, shelf life, and sensory characteristics of fresh and precooked beef patties

The objective was to examine shelf stability, cooked product yield, and sensory characteristics of beef patties that had no binder (Control), incorporated soy flour (Textured Vegetable Protein; TVP) or one of three dry potato extracts: X-TRATOS™ (potato extract), X-TRATOS™ O (potato extract with mustard), or X-TRATOS™ W (potato extract with sodium acid pyrophosphate). In retail display patties, all binders decreased discoloration and lipid oxidation compared to Control, and X-TRATOS™ O was superior (P < 0.05) to all other treatments. Cooking yield was higher (P < 0.05) in patties containing potato extracts compared with patties containing TVP, which had higher yield than Control patties. Beef patties with potato extracts were juicier (P < 0.05) than Control and TVP patties and had higher (P < 0.05) overall acceptability than Control patties. We conclude that potato extracts are effective binders for use in fresh or precooked beef patties because they improve retail shelf life, cooked product yield, and sensory characteristics.

Retail Display Properties and Consumer Perception of Extended Aged Beef Topically Treated with Ascorbic Acid and Rosemary Extract

Extended aging increases browning and decreases redness in fresh beef. The goal of this study was to test an already proven combination of antioxidants (0.05% ascorbic acid + 0.1% rosemary extract) using a method that could be applied at the retail level to simply and effectively extend the shelf-life of extended aged beef. The specific objective was to analyze the effect of topical application of ascorbic acid and rosemary extract on color, lipid oxidation, microbial growth, and sensory perception of beef longissimus lumborum (LL; n = 12) and semimembranosus (SM; n = 12) muscles wet aged at 0°C for 14, 28, and 42 (extended aging period) days. After aging, steaks were cut, sprayed with 2 mL of a 0.05% ascorbic acid + 0.1% rosemary extract solution (treated) or untreated (control), and subjected to retail display. Antioxidant treated LL steaks had greater (P < 0.05) L* (lightness) values, but lower (P < 0.05) a* (redness) and b* (yellowness) values than control steaks. Furthermore, antioxidant treatment decreased (P < 0.05) browning on d 4 of retail display compared to control steaks. Consumers scored antioxidant treated SM steaks as less tender on d 28, more juicy on d 14 but less juicy on d 18 and 42. Antioxidant treatment did not affect lipid oxidation, microbial growth, or sensory flavor scores. As expected, longer aging periods resulted in less color stability of LL and SM steaks. Although the antioxidant treatment resulted in measurable subjective color improvements, these improvements are likely not detectable by the consumer.

Influence of extended aging on beef quality characteristics and sensory perception of steaks from the biceps femoris and semimembranosus

The objective was to determine the influence of post-fabrication aging (2, 14, 21, 42, and 63days) on beef quality characteristics and consumer sensory perception of biceps femoris (BF) and semimembranosus (SM) steaks. Lipid oxidation and aerobic plate counts increased (P<0.05) with longer aging periods and retail display times. An aging period by day of retail display interaction (P<0.05) was observed for a* and b* values of the BF and SM. Warner-Bratzler shear force values decreased (P<0.05) with longer aging for the SM, while no difference was observed for the BF. Consumer panel results revealed that longer aging periods increased (P<0.05) acceptability of the SM, tenderness of both muscles, and tended to increase (P=0.07) juiciness of the SM. Our results show that extended aging reduces retail color stability yet has positive effects on consumer perception of tenderness of both muscles and overall acceptability of the SM.

Effects of dietary potato by-product and rumen-protected histidine on growth, carcass characteristics and quality attributes of beef

We hypothesized that variable composition in finishing rations, more specifically; the proportion of potato-by-product (PBP) and rumen protected histidine (His) supplementation may influence growth and meat quality attributes. Two different diets were fed (1) finishing ration with corn and barley as grains (CB, n = 20) and (2) substitution of 10% corn, DM basis, with PBP (PBP, n = 20). Additionally, half of each dietary treatment received 50 g/hd/d rumen protected His (HS, n= 20) while the other half received no supplement (NS, n = 20). Inclusion of 10% PBP or HS did not affect growth or carcass traits. Color stability was analyzed using Hunter color values as well as AMSA visual appraisal in both longissimus thoracis (LT) and gluteus medius (GM) muscles. The LT, but not the GM, of CB steers was more color stable over a 9 d simulated retail display compared to those fed a PB diet. Steers receiving HS produced significantly (P < 0.05) more color stable LT and GM steaks.