The objective of this study was to identify the threshold for color and discoloration for consumers to purchase ground beef and to determine the best objective measurement to predict consumer purchase intent. This study was designed in 2 phases, with Phase 1 requiring consumers to evaluate ground beef samples of multiple days of display simultaneously, and Phase 2 having consumers evaluate samples of only a single day of display. Ground beef packages (80% lean) were evaluated for overall appearance liking and purchase intent (yes/no) by consumers (n=216 and 318). Additionally, packages were evaluated for L*, a*, b*, calculated percentage of metmyoglobin, oxymyoglobin, chroma, hue angle, and trained sensory panel redness and discoloration scores. Models showed that each of the objective measures evaluated were predictors (P<0.05) of consumer purchasing intent. All logistic regression equations (P<0.01) had high R2 values of 0.48 to 0.86 (Phase 1) and 0.26 to 0.65 (Phase 2) and correctly classified 78.1% to 90.1% (Phase 1) and 70.5% to 84.0% (Phase 2) of samples as would/would not purchase. Linear regression equations predicting consumer overall appearance ratings with objective measures also resulted in significant (P<0.01) models, with R2 values of 0.57 to 0.93 and 0.35 to 0.54. The a* values of 21.6, 24.6, 28.3, and 30.5 (Phase 1) and 20.7, 26.2, 31.7, and 35.4 (Phase 2) correspond with consumers being 50%, 75%, 90%, and 95% likely to purchase the product at full price. However, if the product was discounted, the a* values were reduced to 17.9, 21.4, 25.0, and 27.4 (Phase 1) and 17.7, 22.7, 27.7, and 31.1 (Phase 2). The models generated from this study provide the ability to predict consumer willingness to purchase ground beef and provide ground beef processors an indication of potential consumer purchasing behaviors based upon objective values that are easy to measure.

The objective of this study was to compare the quality characteristics of current plant-based protein ground beef alternatives (GBA) to ground beef (GB) patties of varying fat percentages. Fifteen different production lots (n = 15/fat level) of 1.36 kg GB chubs of 3 different fat levels (10%, 20%, and 27%) were collected from retail markets in the Manhattan, KS area. Additionally, GBA products including a foodservice GBA (FGBA), a retail GBA (RGBA), and a traditional soy protein–based GBA (TGBA) currently available through commercial channels were collected. Consumers (n = 120) evaluated sample appearance, juiciness, tenderness, overall flavor liking, beef flavor liking, texture liking, and overall liking. Additionally, samples were evaluated for color, texture profile, shear force, pressed juiciness percentage (PJP), pH, and fat and moisture percentage. All 3 GB samples rated higher (P < 0.05) than the 3 GBA samples for appearance liking, overall flavor liking, beef flavor liking, and overall liking by consumers. Similar results were found with trained sensory panelists, which rated the GBA as less (P < 0.05) juicy, softer (P < 0.05), and lower (P < 0.05) for beef flavor and odor intensity and higher (P < 0.05) for off-flavor intensity than the GB. Moreover, the GBA had less (P < 0.05) change in shape through cooking and a lower (P < 0.05) percentage of cooking loss and cooking time than the GB. Also, the GBA all had lower (P < 0.05) shear force and PJP values than the GB. The color of the GBA differed (P < 0.05) from the GB, with the GB samples being more (P < 0.05) red in the raw state. These results indicate that the GBA provide different eating and quality experiences than GB and should thus be considered as different products by consumers and retailers.

Woody breast (WB) is a myopathy observed in broiler Pectoralis major (PM) characterized by its tough and rubbery texture with greater level of calcium content. The objective of this study was to investigate the functionality/integrity of WB sarcoplasmic reticulum (SR), which may contribute to the elevated calcium content observed in WB and other factors that may influence WB texture. Fourteen Ross line broiler PM [7 severe WB and 7 normal (N)] were selected, packaged, and frozen at −20°C at 8 h postmortem from a commercial processing plant. Samples were used to measure pH, sarcomere length, proteolysis, calpain activity, collagenase activity, collagen content, collagen crosslinks density, and connective tissue peak transitional temperature. Exudate was also collected from each sample to evaluate free calcium concentration. The SR fraction of the samples was separated and utilized for proteomic and lipidomic analysis. The WB PM had a higher pH, shorter sarcomeres, lower % of intact troponin-T, more autolyzed μ/m calpain, more activated collagenase, greater collagen content, greater mature collagen crosslinks density, and higher connective tissue peak transitional temperature than the N PM (p ≤ 0.05). Exudate from WB PM had higher levels of free calcium than those from N PM (p &lt; 0.05). Proteomics data revealed an upregulation of calcium transport proteins and a downregulation of proteins responsible for calcium release (p &lt; 0.05) in WB SR. Interestingly, there was an upregulation of phospholipase A2 (PLA2), and cholinesterase exhibited a 7.6-fold increase in WB SR (p &lt; 0.01). Lipidomics data revealed WB SR had less relative % of phosphatidylcholine (PC) and more lysophosphatidylcholine (LPC; p &lt; 0.05). The results indicated that upregulation of calcium transport proteins and downregulation of calcium-release proteins in WB SR may be the muscle’s attempt to regulate this proposed excessive signaling of calcium release due to multiple factors, such as upregulation of PLA2 resulting in PC hydrolysis and presence of cholinesterase inhibitors in the system prolonging action potential. In addition, the textural abnormality of WB may be the combined effects of shorter sarcomere length and more collagen with greater crosslink density being deposited in the broiler PM.

This study’s objective was to understand the relationships between biochemical tenderness components andobjective/sensory measure of tenderness of 8 muscles from beef carcasses. Longissimus thoracis (LT), pectoralis profundus (PP), supraspinatus, triceps brachii (TB), gluteus medius (GM), rectus abdominus (RA), rectus femoris, and semitendinosus (ST) were collected from 10 USDA upper 2/3 Choice beef carcasses and assigned to a 2- or 21-d aging period (n=160). Troponin-T degradation, desmin degradation, sarcomere length, collagen content, mature collagen crosslink density, intramuscular lipid content, pH, Warner-Bratzler Shear Force (WBSF), and trained sensory panel analyses were measured. A Pearson correlation analysis was conducted to determine the relationship between each tenderness contributor measured in this study with WBSF or the overall tenderness evaluated by the trained panelist for each of the 8 muscles.In addition, multivariate regression models were constructed to confirm this relationship. The results showed that muscle anatomical locations and physiological functions driven by muscle fiber types may explain some of the biochemical/tenderness differences found in this study. The correlation analysis showed that each muscle had a specific tenderness factor(s)that contributed to the overall tenderness. For instance, tenderness for LT, TB, GM, RA, and ST may be influenced more by proteolytic degradation, while the collagen characteristics may primarily influence tenderness for PP. Also, lipid content has a significant influence on GM tenderness. Finally, the multivariate regression model showed that almost all of the biochemical measurements conducted in this study contributed to overall tenderness to some degree across muscles.Increasing the knowledge base on the various tenderness components’ level of contribution will allow end-users to develop specific tenderness management strategies to ensure consistent tenderness in beef products.

A total of 72 male Boer goat kids (21.7 ± 0.5 kg) were fed for 21 d with 3 kids per pen and 12 pens per treatment. Dietary treatments were: 0% inclusion of dried distillers grains with solubles (DDGS; 0% DDGS) or 33% DDGS inclusion (33% DDGS) and were provided ad libitum. Goats and feeders were weighed weekly to collect body weights (BW) and determine feed disappearance in order to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F). At the conclusion of the feeding study, a subset (n = 30; 2–3 goats from each pen representing six6 pens per treatment) of goats were harvested, carcasses evaluated, and loins were fabricated into 2.54 cm chops. Goat chop discoloration was evaluated by trained panelists and measured for L*, a*, and b* values on days 0, 4, 7, and 10 under retail display conditions. Samples were collected and analyzed for lipid oxidation, fatty acid profile, and hydrophilic and lipophilic antioxidant capacity. No evidence of differences was observed for final BW, ADFI, G:F, and carcass characteristics (P > 0.05). However, goats fed the 0% DDGS diet had greater ADG compared with those fed a diet containing 33% DDGS (P = 0.05). Overall, visual evaluation of discoloration, L*, a*, and b* as well as lipid oxidation data confirmed that feeding 33% DDGS to goats had no effect on goat chop discoloration and lipid oxidation (P > 0.10). However, all chops demonstrated a display effect, which they increased in visual discoloration and lipid oxidation and decreased in a* and b* values (P < 0.01) over the entirety of the 10-d period of retail display, regardless of the dietary treatments. As expected, feeding 33% DDGS to goats decreased relative percentage of multiple and total monounsaturated fatty acids, but increased relative percentage of multiple and total polyunsaturated fatty acids (PUFA; P < 0.05). The antioxidant capacity measurements showed no treatment difference in the hydrophilic portion (P > 0.10), but chops from the 33% DDGS treatment had greater lipophilic antioxidant activity compared with the 0% DDGS chops (P < 0.05). In conclusion, including 33% DDGS to the diet may negatively impact goat growth performance, but did not impact any carcass characteristics. Feeding a diet with 33% DDGS resulted in an increase in the PUFA content of goat chops but did not appear to impact meat color or lipid oxidation. The supposed negative consequence from increased PUFA is likely counterbalanced by the increased antioxidant capacity in the lipid component of meat, resulting in no difference in meat shelf-life.

Although studies evaluating freezing are prevalent, most have used varied postmortem aging times to facilitate study design. The lack of a comprehensive study evaluating equally aged fresh and frozen steaks prevents a true under-standing of the impact of freezing. Therefore, the objective of this study was to determine the eating quality and consumer perception differences between fresh and frozen beef steaks of 3 equal aging periods. Beef carcasses were selected from a processing plant on 2 kill dates 1 wk apart to allow for a 1-wk freezing period, fabricated, and aged for 21, 28, or 35 d. On the same day, all samples of equal aging periods were fed to consumer and trained sensory panelists, sheared for shear force, and powdered for lab assays. For consumer panels, the first 4 steaks were given with no additional information, whereas the last 4 steaks were served with the labels “previously frozen” or “fresh, never frozen.” The consumer panelists rated the frozen samples as more tender (P0.05). Even when given additional information, the perception of quality was not impacted (P>0.05). Similarly, the trained panelists rated the frozen samples higher (P<0.05) than the fresh counterparts for overall tenderness, but the fresh samples scored higher (P<0.05) for initial and sustained juiciness. Supporting the sensory data, the frozen steaks had lower (P<0.05) shear force values regardless of the aging period. However, the fresh samples resulted in lower (P<0.05) purge and cook loss. Although some meat quality factors were impacted by freezing, the overall eating quality and perception of quality were not negatively impacted. Therefore, frozen meat should not be discounted due to the eating quality or perception of the quality of beef steaks.