Consumer palatability scores and volatile beef flavor compounds of five USDA quality grades and four muscles

Proximate data, consumer palatability scores and volatile compounds were investigated for four beef muscles (Longissimus lumborum, Psoas major, Semimembranosus and Gluteus medius) and five USDA quality grades (Prime, Upper 2/3 Choice, Low Choice, Select, and Standard). Quality grade did not directly affect consumer scores or volatiles but interactions (P < 0.05) between muscle and grade were determined. Consumer scores and volatiles differed (P < 0.05) between muscles. Consumers scored Psoas major highest for tenderness, juiciness, flavor liking and overall liking, followed by Longissimus lumborum, Gluteus medius, and Semimembranosus (P < 0.05). Principal component analysis revealed clustering of compound classes, formed by related mechanisms. Volatile n-aldehydes were inversely related to percent fat. Increases in lipid oxidation compounds were associated with Gluteus medius and Semimembranosus, while greater quantities of sulfur-containing compounds were associated with Psoas major. Relationships between palatability scores and volatile compound classes suggest that differences in the pattern of volatile compounds may play a valuable role in explaining consumer liking

Feeding microalgae meal (All-G Rich (TM); Schizochytrium limacinum CCAP 4087/2) to beef heifers. I: Effects on longissimus lumborum steak color and palatibility

Citation: Phelps, K. J., Drouillard, J. S., O'Quinn, T. G., Burnett, D. D., Blackmon, T. L., Axman, J. E., . . . Gonzalez, J. M. (2016). Feeding microalgae meal (All-G Rich (TM); Schizochytrium limacinum CCAP 4087/2) to beef heifers. I: Effects on longissimus lumborum steak color and palatibility. Journal of Animal Science, 94(9), 4016-4029. doi:10.2527/jas2016-0487The objective of this study was to examine effects of 4 levels of microalgae meal (All-G Rich, Schizochytrium limacinum CCAP 4087/2; Alltech Inc., Nicholasville, KY) supplementation to the diet of finishing heifers on longissimus lumborum (LL) steak PUFA content, beef palatability, and color stability. Crossbred heifers (n = 288; 452 +/- 23 kg initial BW) were allocated to pens (36 pens and 8 heifers/ pen), stratified by initial pen BW (3,612 +/- 177 kg), and randomly assigned within strata to 1 of 4 treatments: 0, 50, 100, and 150 g . heifer(-1) . d(-1) of microalgae meal. After 89 d of feeding, cattle were harvested and LL were collected for determination of fatty acid composition and Warner-Bratzler shear force (WBSF), trained sensory panel evaluation, and 7-d retail color stability and lipid oxidation analyses. Feeding microalgae meal to heifers increased (quadratic, P 0.25) but tended (P = 0.10) to increase total PUFA in a quadratic manner (P = 0.03). Total omega-6 PUFA decreased (linear, P = 0.01) and total omega-3 PUFA increased (quadratic, P 0.16); however, off-flavor intensity increased with increasing concentration of microalgae meal in the diet (quadratic, P 0.19); therefore, the negative effects of microalgae on color stability were not due to fiber metabolism differences. Feeding microalgae meal to finishing heifers improves PUFA content of beef within the LL, but there are adverse effects on flavor and color stability

Feeding microalgae meal (All-G Rich (TM); Schizochytrium limacinum CCAP 4067/2) to beef heifers. II: Effects on ground beef color and palatability

Citation: Phelps, K. J., Drouillard, J. S., O'Quinn, T. G., Burnett, D. D., Blackmon, T. L., Axman, J. E., . . . Gonzalez, J. M. (2016). Feeding microalgae meal (All-G Rich (TM); Schizochytrium limacinum CCAP 4067/2) to beef heifers. II: Effects on ground beef color and palatability. Journal of Animal Science, 94(9), 4030-4039. doi:10.2527/jas2016-0488The objective of this study was to examine the effects of feeding microalgae meal (All-G Rich, Schizochytrium limacinum CCAP 4087/2; Alltech Inc., Nicholasville, KY) to finishing heifers on 85% lean and 15% fat (85/15) ground beef PUFA content, palatability, and color stability. Crossbred heifers (n = 288; 452 +/- 23 kg initial BW) were allocated to pens (36 pens and 8 heifers/pen), stratified by initial pen BW (3,612 +/- 177 kg), and randomly assigned within strata to 1 of 4 treatments: 0, 50, 100, and 150 g center dot heifer(-1) center dot d(-1) of microalgae meal. After 89 d of feeding, a subset of heifers (3/pen) was harvested and the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius were collected for processing into ground beef. At 42 d postmortem, 85/15 ground beef was formulated and formed into 112-g patties and fatty acid composition, subjective palatability, and 96-h retail color stability analyses were conducted. Increasing dietary microalgae meal concentration increased ground beef 20: 5n-3 and 22: 6n-3 fatty acids (quadratic, P 0.12). Feeding microalgae meal affected (P = 0.02) b* at 24 h and decreased (linear, P = 0.08) b* at 48 h. From h 0 to 36 of display, microalgae affected redness of patties (P 0.20) but tended to affect (P = 0.10) cohesiveness scores. As the amount of microalgae meal fed to heifers increased, beef flavor intensity decreased (linear, P < 0.01) and off-flavor intensity increased (quadratic, P < 0.05). Surface oxymyoglobin and metmyoglobin were impacted by microalgae meal from 12 to 36 h of display (P < 0.01). From 48 to 84 h of display, feeding microalgae meal to heifers decreased (linear, P < 0.09) surface oxymyoglobin and increased (linear, P < 0.02) surface metmyoglobin of patties. Although feeding microalgae meal to heifers increases the PUFA content of 85/15 ground beef, there are undesirable effects on flavor and color stability

Influence of Production Practice Information on Consumer Eating Quality Ratings of Beef Top Loin Steaks

The purpose of this study was to identify if consumers’ palatability scores of beef top loin steaks were affected by disclosing production practices or brands related to each product. Strip loins were selected to represent 5 treatments: Grain-Fed Natural (Natural), Certified Angus Beef (CAB), Local Grass Fed (Grass), USDA Select (Conventional), and USDA Certified Organic (Organic). Two separate experiments were conducted (n = 120/experiment). In Experiment 1 and 2, panelists received the 5 treatment samples in a standard blind testing format in segment 1 (S1). In the second segment (S2) of Experiment 1, short descriptions were read aloud to participants before receiving each of their 5 samples, but all samples were actually USDA Select (false disclosure). In the second segment of Experiment 2, treatment descriptions were provided that matched the 5 treatments samples (true disclosure). When consumers evaluated samples in S1, they rated the Natural and CAB samples more tender and juicier (P < 0.05) than the other 3 treatments, and Organic was the least tender. Flavor and overall liking were greater (P < 0.05) for Natural and CAB steaks, while Conventional was intermediate, and flavor and overall liking were lowest for Grass and Organic (P < 0.05). When consumers received Select samples representing the 5 treatments, false disclosure decreased tenderness and juiciness of Natural, increased flavor liking of CAB, and increased tenderness, flavor liking, and overall liking of Organic (P < 0.05). True treatment disclosure increased flavor liking and overall liking of CAB and Grass, increased overall liking of Natural, and decreased juiciness of Conventional (P < 0.05). These results indicate consumers’ perception of eating quality can be influenced by quality differentiated brand names and labeling claims, particularly claims related to production practices

Effect of extended postmortem aging and steak location on myofibrillar protein degradation and Warner-Bratzler shear force of beef M. semitendinosus steaks

Citation: Phelps, K. J., Drouillard, J. S., Silva, M. B., Miranda, L. D. F., Ebarb, S. M., Van Bibber-Krueger, C. L., . . . Gonzalez, J. M. (2016). Effect of extended postmortem aging and steak location on myofibrillar protein degradation and Warner-Bratzler shear force of beef M. semitendinosus steaks. Journal of Animal Science, 94(1), 412-423. doi:10.2527/jas2015-9862The objective of this study was to evaluate the effect of steak location and postmortem aging on cooked meat tenderness and myofibrillar protein degradation of steaks from M. semitendinosus (ST). Following harvest and a 6 d chill period, the left ST was removed from carcasses of crossbred feedlot steers (n = 60, average hot carcass weight 427 +/- 24 kg). Each ST was fabricated into ten 2.54-cm thick steaks originating from the proximal to distal end of the muscle. Steaks cut adjacent to each other were paired, vacuum packaged, and randomly assigned to 7, 14, 21, 42, or 70 d of aging at 2 +/- 1 degrees C. After aging, within each steak pair, steaks were randomly assigned to Warner-Bratzler shear force or myofibrillar proteolysis analysis (calpain activity and desmin and troponin-T degradation). Muscle fiber type and size were also determined at the 2 ends of the muscle. There was no location x d of aging interaction (P = 0.25) for ST steak WBSF. Steak location affected (quadratic, P 0.13). Type I, IIA, and IIX muscle fibers were larger at the proximal end of the muscle than the distal end (P < 0.01). Increasing d of aging improved WBSF (quadratic, P < 0.01) for the duration of the 70 d postmortem period. As d of aging increased, intact calpain-1 activity decreased (quadratic, P < 0.01) with activity detected through 42 d. Day of aging affected autolyzed calpain-1 (linear, P < 0.01) and calpain-2 activity (quadratic, P < 0.01). Through d 70 of aging, the intensity of intact 55 kDa desmin band decreased (linear, P < 0.01), while there was an increase (linear, P < 0.01) in the degraded 38 kDa band. Similarly, d of aging increased troponin-T proteolysis, indicated by a decrease (quadratic, P < 0.01) in intensity of the intact 40 kDa band and an increase (linear, P < 0.01) in the 30 kDa degraded band. Intramuscular WBSF differences are not due to proteolytic activity or myofibrillar degradation and seem related to muscle fiber size. The improvement of ST steak WBSF through 70 d of aging is partly due to continued degradation of desmin and troponin-T. Calpain proteolytic analysis indicates that autolyzed calpain-1 and calpain-2 may be involved in extended postmortem myofibrillar protein proteolysis

Palatability of Beef Strip Loin Steaks Representing Various Marbling and Maturity Levels from Grain-Fed Beef

This study compared palatability traits of beef strip loin steaks with varying marbling scores from young and mature grain-fed beef. Strip loins (n = 150) were selected from grain fed cattle representing ten treatments with the following USDA marbling scores: Slightly Abundant or greater (SLAB+), Moderate or Modest (MD/MT), Small (SM), Slight (SL), and Traces or Practically Devoid (TR/PD) from young “A” maturity carcasses (Y) and mature “C” or greater maturity carcasses (M). Subprimals were fabricated into 2.5-cm steaks at 21 d postmortem and stored frozen until further analysis. Consumer (n = 120) sensory panelists evaluated cooked steaks for tenderness, juiciness, flavor liking, and overall liking. Trained panelists (n = 15 sessions) evaluated each sample for initial and sustained juiciness, initial and sustained tenderness, flavor intensity, and off-flavor intensity. For all traits, consumer and trained panelists’ scores generally decreased with decreasing marbling score, regardless of maturity. According to consumers, maturity had no effect on juiciness or flavor liking within each marbling score, except flavor liking of SLAB+ was greater (P < 0.05) for young than mature carcasses. Conversely, young carcasses had greater tenderness scores than mature within all marbling categories except SM, which translated to greater overall liking of MD/MT, SL, and TR/PD of young compared to their mature counterparts (P < 0.05). Trained panelists detected very few differences between young and mature samples within their respective marbling score; however, M-MD/MT had lower initial and sustained tenderness coupled with greater off-flavor intensity than Y-MD/MT (P < 0.05). Mature samples with SLAB+ and MD/MT marbling were rated greater than or equal to Y-SM for all traits, indicating the presence of marbling from feeding a grain diet prior to harvest may elicit a similar eating experience to young beef by offsetting negative palatability traits often associated with mature beef

Comparing Honduran and United States Consumers’ Sensory Perceptions of Honduran and U.S. Beef Loin Steaks

The objective of this study was to compare the eating quality characteristics of beef from the United States and Honduras and to assess the willingness of Honduran and U.S. consumers to pay for these products. All U.S. sourced strip loins from grain-finished cattle, aged 21 d, were selected to equally represent USDA Select (SEL; n = 6) and upper 2/3 (Top) Choice (TC; n = 6) quality grades. Additionally, strip loins (n = 6) from Honduran grass-finished (HGRASS) cattle and grain-finished (HGRAIN) cattle (n = 6) were collected from a commercial abattoir in Siguatepeque, Honduras and aged 21 d. Samples were evaluated on 8-point hedonic scales for flavor, tenderness, juiciness, and overall liking by 240 consumers in each country. Consumers indicated if each trait was acceptable, and willingness to pay for each sample was rated in U.S. dollars (or the Honduran Lempiras equivalent): $0, 3, 6, and 10 per 0.45 kg. Chemical composition and Warner-Bratzler shear force (WBSF) were also determined. The TC had greater (P 0.05) from HGRAIN. The HGRAIN had greater WBSF values than TC and SEL, which did not differ (P > 0.05); however, HGRASS was similar (P > 0.05) to all other treatments. The TC had greater tenderness and flavor liking scores (P < 0.05) than all other treatments, followed by SEL, HGRASS, and HGRAIN, with a significant difference between each treatment. Honduran consumers assigned greater ratings for tenderness and flavor liking when compared to U.S. consumers. The lowest rated treatment in both countries was Honduran grain-finished followed by Honduran grass-finished. Consumers in Honduras were willing to pay more for samples when compared to U.S. consumers. Consumers were also willing to pay a premium for products with greater palatability, regardless of the country of origin

Palatability of New Zealand Grass-Finished and American Grain-Finished Beef Strip Steaks of Varying USDA Quality Grades and Wet-Aging Treatments

The objective of this study was to evaluate palatability of strip loin steaks from grass- and grain-fed beef across5 United States Department of Agriculture (USDA) quality grades and 3 wet-aging periods. Beef strip loins (N=200; 20/USDA quality grade×fed cattle type) representing 5 USDA quality grades (USDA Prime, Top Choice [Average and High Choice], Low Choice, Select, and Standard) and 2 fed cattle types (New Zealand grass-finished and U.S. grain-finished)were used in the study. Each strip loin was equally portioned into thirds and randomly assigned to one of 3 wet-aging periods (7 d, 21 d, or 42 d). Consumer panelists (N=600; 120/location: Texas, California, Florida, Kansas, and Pennsylvania) evaluated 8 grilled beef steak samples for palatability traits, acceptability, and eating quality. All palatability traits were impacted by the interaction of diet×quality grade (P&lt;0.05). Although similar (P&gt;0.05) to grass-fed Prime steaks for juiciness, tenderness, and overall liking, grain-fed Prime steaks rated higher (P&lt;0.05) than all other grass- and grain-finished treatments for all palatability attributes. Grass-finished Top Choice, Low Choice, and Standard steaks rated higher (P&lt;0.05) than the respective grain-finished quality grades for juiciness and tenderness. Grain-finished Standard steaks rated lower (P&lt;0.05) than all other grass- and grain-finished treatments for juiciness, tenderness, and overall liking but were similar (P&gt;0.05) to grass-finished Standard steaks for flavor liking. Our results indicate that beef strip loin steaks of similar quality grades from grass-finished New Zealand cattle produce similar eating experiences when compared with those from U.S. grain-finished beef, even following extended postmortem aging. This indicates improved palatability for consumers based on marbling without respect to grass- or grain-finishing diets

Effects of Marbling and Postmortem Aging on Consumer Assessment of United States Lamb Loin

Consumer sensory analysis was performed to evaluate the effects of three marbling categories [LOW, Intermediate (MED), and HIGH] and 2 postmortem aging categories (21 d and 42 d) on the palatability of lamb loin chops as determined by U.S. consumers and to determine the relationship between marbling, flank streaking, intramuscular fat percentage (IMF), and palatability traits. Marbling and aging did not interact to affect any of the scores for palatability attributes, their acceptances, or the frequency of their overall eating quality classifications (P 0.05). Aging also influenced (P < 0.05) all traits, as consumers scored 21 d samples greater for all palatability traits than their 42 d counterparts. A greater (P < 0.05) percentage of consumers categorized 42 d samples as ‘unsatisfactory’ and fewer as ‘better than everyday’ or ‘premium quality’ than 21 d samples. A larger proportion of consumers categorized HIGH samples as ‘premium quality’ than MED or LOW and fewer called HIGH ‘good everyday quality’ compared to MED (P < 0.05). Flank streaking, marbling score, and IMF were all influenced (P < 0.01) by marbling category in a linear fashion. Increasing marbling score, more so than flank streaking, was positively linked to increasing eating quality scores. Also, tenderness, juiciness and flavor liking are major drivers for consumer sensory scores for overall liking, with flavor liking having the strongest relationship to overall liking of lamb. Overall, consumers preferred HIGH marbling over LOW and MED marbling loin chops, but had difficulty distinguishing between LOW and MED. Furthermore, extending postmortem aging of lamb loin from 21 to 42 d reduced scores for eating quality traits