USDA MATURITY INDICES AND PALATABILITY OF BEEF RIB STEAKS1

In a population of 195 beef carcasses, as maturity increased (by whole USDA groups) from A to B, flavor, tenderness and overall palatability ratings for rib steaks decreased (P < .05); further increases in maturity (B vs. E) resulted in subsequent decreases (P < .05) in tenderness and overall palatability. Subdivision of whole maturity groups into thirds and subsequent data analyses supported precepts in USDA grade standards of declining palatability with advancing maturity, but the declines, when they occurred, were nearly linear through the extremes (from A^? to E⁺) and did not support the concept, in USDA grade standards, of a precipitous decline in eating satisfaction at or near the B⁺/C^? maturity line. Among seven carcass maturity indices, all were similarly and singularly related (P < .05) to palatability of rib steaks, with some measure of skeletal maturity (the best of these was color/shape of the rib bones) plus some measure of muscle maturity (the best of these was color of the longissimus muscle) combining (by means of multiple regression analyses) to predict tenderness (panel ratings and shear values) with maximum precision. Neither total pigment concentration (a chemical measure of muscle color), amount of ether-extractable lipid (a chemical measure of intramuscular fatness) nor marbling score (a visual measure of intramuscular fatness) was able to explain more than about 7% of the observed variability in palatability ratings for cooked beef steaks. Data suggest that more attention should be paid to appearance of rib bones in a carcass (to better assess effects of maturity) and that less attention could be paid to differences between SLIGHT, SMALL and MODEST in marbling in the ribeyes, in attempting to predict, via USDA grading, the palatability of beef rib steaks.     

RELATIONSHIP OF USDA MARBLING GROUPS TO PALATABILITY OF COOKED BEEF

As marbling increased from“practically devoid” to“moderately abundant”, loin steaks were more palatable (P<0.05) about 2/3 of the time, round steaks were more palatable (P<0.05) about 1/8 of the time, and loin steaks were more likely to be assigned high (≥6.00) panel ratings and to have low (≤3.63 kg) shear values. However, increases in marbling from“slight” to“moderately abundant” (A maturity) and from“small” to“moderately abundant” (A+B maturity) had little or no efect on percentage incidence of loin or round steaks with panel ratings ≤2.99 or ≥4.00, or with shear values ≥6.35 kg or ≤4.99 kg. Differences in marbling explained about 33% (loin) and 7% (top round) of the variation in overall palatability ratings in A, B, C, and A+B maturity carcasses.     

Palatability of Beef Skirt Steaks as Influenced by Grade/Maturity Group, Anatomical Location and Mechanical Tenderization

Beef inside and outside skirts (n = 120) obtained from 30 U.S. Choice carcasses and from 30 U.S. Utility cow carcasses were used in a study to evaluate anatomical location, grade/maturity group and method of mechanical tenderization on the palatability of cooked “fajita” beef. Ratings for juiciness, muscle fiber tenderness, overall tenderness, and overall palatability were higher (P < 0.05) for outside skirts than for inside skirts. Skirt steaks—inside and outside—from U.S. Choice carcasses were juicier, more tender overall, and more palatable overall than skirt steaks from U.S. Utility carcasses. Cubing, as a method of tenderization, was more useful for skirts from U.S. Utility carcasses than for skirt steaks from U.S. Choice carcasses.     

RELATIONSHIP OF USDA QUALITY GRADES TO PALATABILITY OF COOKED BEEF1

Prime carcasses produced loin and round steaks that were more palatable (P < 0.05) than were those from carcasses of Choice through Canner (7 grades) in 85.7% of comparisons and from carcasses of Choice through Standard (3 grades) in 69.0% of comparisons; comparable percentages were 71.4% (6 grades) and 42.9% (2 grades) for Choice and 74.3% (5 grades) and 35.7% (1 grade) for Good. Among Prime through Standard carcasses, grade predicted flavor, tenderness and overall palatability of loin steaks with 30 to 38% accuracy, but could explain no more than 8% of the variation in panel ratings/shear force values of round steaks.     

Characterization of cutability and palatability attributes among different slaughter groups of beef cattle

Fifteen slaughter cattle from five groups (Charolais crossbred bulls, Brahman crossbred steers, Holstein steers, mixed-Exotic crossbred heifers and Hereford-Angus crossbred steers) were randomly selected from a commercial feedlot. Time-on-feed was 108, 114, 102, 108 and 145 days for the aforementioned groups, respectively. Carcasses from Charolais crossbred bulls had the highest percentage yield of chuck and round, but the lowest percentage yield of loin; hereford-Angus crossbred steers had the lowest percentage yield of round and Holstein steers had the lowest percentage yield of rib. Carcasses from Charolais crossbred bulls had the highest percentage yield of major retail-ready subprimals and lean trim, Hereford-Angus crossbred steers had the highest percentage yield of fat trim and Holstein steers had the highest percentage yield of bone from the major wholesale cuts. Mean percentage yields of closely trimmed, boneless retail cuts were highest for carcasses from the bulls and lowest for carcasses from the Hereford-Angus steers. Although Holstein steer carcasses had less fat trim than Brahman-crossbred steers mixed-Exotic heifers, this advantage was largely offset by their higher percentage of bone. Loin steaks from carcasses of Charolais crossbred bulls, Holstein, mixed-Exotic heifers were comparable (P > 0·05)with those of Hereford-Angus steers for shear force and sensory panel tenderness ratings. However, loin steaks from carcasses of Brahman-crossbred steers had significantly higher (P < 0·05) shear force values (least tender) and lower (P < 0·05) tenderness and overall palatability ratings. No diffeerences (P > 0·05) were found for flavor desirability of loin steaks among any of the groups. For bottom round steaks, Hereford-Angus steers received the highest palatability ratings while those from Holstein steers received the lowest palatability ratings.     

CONSUMER EVALUATION OF THE PALATABILITY OF USDA SELECT,USDA CHOICE AND CERTIFIED ANGUS BEEF STRIP LOIN STEAKS FROM RETAIL MARKETS IN LUBBOCK,TEXAS, U.S.A.

ABSTRACT

Select, Choice and Certified Angus Beef (CAB) strip loin steaks were sold in Lubbock, TX to determine consumer acceptability. A home survey was attached to each package of steaks (return = 191 steak evaluations). Consumers did not detect differences in tenderness or flavor, but rated CAB steaks juicier (P < 0.05) than Select or Choice. However, 68% of CAB consumers rated steaks as extremely or very tender, but less than half rated Choice and Select steaks the same way. Consumer tenderness and flavor scores for Select steaks were more variable, but consumer satisfaction and tenderness acceptability did not differ (P > 0.05) between grades. Trained sensory panelists rated CAB steaks higher (P < 0.05) than Choice or Select for all palatability traits except flavor intensity. Shear force decreased (P < 0.05) by quality grade as CAB steaks sheared with the least resistance. These results showed marbling influenced objective palatability measures and decreased the variation in both objective and consumer measures of palatability.

PRACTICAL APPLICATIONS

Quality grades were established to predict beef palatability, but marbling can be an unreliable predictor of tenderness. Branded beef programs, such as Certified Angus Beef (CAB), have been developed to distinguish higher palatability products and provide more consistent products for consumers. Consumers can distinguish between levels beef tenderness and are willing to pay a premium for tender beef. Moreover, consumers find product consistency is moderately important when purchasing fresh beef. Therefore, the purpose of this study was to determine consumer acceptability based on in‐home evaluations of strip loin steaks from United States Department of Agriculture Select and Choice grades and CAB purchased from a retail supermarket environment.

     

Reducing Postmortem Aging Time of Beef with Electrical Stimulation

Two studies (Study 1 = 23 forage-fed steers; Study 2 = 20 grain-fed steers and heifers) were conducted to determine relationships of electrical stimulation (ES) and/or postmortem aging (PA) to tenderness of beef. For Study 1, steaks from ES sides had lower (P < 0.05) Warner-Bratzler shear (WBS) values than steaks from not-ES sides for each PA period. In addition, the percentage reduction in WBS values was greater for the steaks from the ES-Day 2 group (–29.5%) than for steaks from even the longest PA period (14 days) from the not-ES group (–25.8%). For Study 2, during the fist three PA periods (1, 2 and 5 days), ES resulted in more desirable (P < 0.05) flavor ratings (Day l), higher (P < 0.05) tenderness ratings and lower (P < 0.05) WBS values (Day 1, 2, 5) and more desirable (P < 0.05) overall palatability ratings (Day 1, 2). During the last three PA periods (8, 11 and 14 days), ES resulted in higher (P < 0.05) tenderness ratings (Day 8), lower (P < 0.05) juiciness ratings (Day 11, 14) and lower (P < 0.05) WBS values (Day 8). Based on these results, ES had the greatest impact on beef palatability if the period of aging was 8 days or less; with additional aging time, ES effects on palatability were negated. When each treatment (ES, not-ES) was divided into two groups based on median tenderness ratings for the not-ES group, ES had the greatest impact on those carcasses in the “tough” group while ES had little impact on those carcasses in the “tender” group. ES will accelerate the postmortem aging of beef but the aging time reduction and extent of ultimate tenderization appears to be affected by the inherent tenderness of the beef.     

Relationship of USDA Maturity Groups to Palatability of Cooked Beef

In comparison to carcasses of B, C or E maturity, carcasses of A maturity produced broiled steaks which: (a) had higher (P < 0.05) palatability ratings in 62 to 86% of comparisons, (b) were decidedly less variable (C.V.), (c) were more likely to be assigned high (≥ 6.00) and less likely to be assigned low (≤ 2.99) sensory panel ratings, and (d) were more likely to have low (≤ 3.63 kg) and less likely to have high (≥ 6.35 kg) shear force values. Position within the A or A + B maturity group(s) explained 0–4% (loin steaks) and 10–18% (round steaks) of the observed variation in overall palatability ratings and/or shear force values.     

Interrelationships of breed type, USDA quality grade, cooking method, and degree of doneness on consumer evaluations of beef in Dallas and San Antonio, Texas, USA

The objective of this research was to evaluate the consumer controlled factors of cooking method and degree of doneness on top loin steaks from different USDA quality grades (Low Choice, High Select or Low Select) and breed-types (English, Continental European Cross or Brahman Cross). In addition, cities within the same region were evaluated for differences in consumer controlled factors and palatability responses. The in-home product test was conducted in Dallas and San Antonio, Texas, USA. Consumers (n=173) evaluated steaks for overall like (OSAT), tenderness (TEND), juiciness (JUIC), and flavor (FLAV) using 23-point hedonic scales. Respondents in Dallas cooked their steaks to higher degrees of doneness than did those in San Antonio. Outdoor grilling was the most frequently used method of cookery for steaks in both cities. Generally, consumers in San Antonio gave higher palatability ratings to Choice steaks and Dallas consumers gave higher ratings to Select steaks. The interactions of city×cooking method, breed-type×cooking method, and degree of doneness×cooking method were significant for all palatability attributes. In addition, the interaction of cooking method×quality grade was significant for TEND, JUIC, and FLAV. Warner-Bratzler shear (WBS) force was determined on a steak from each strip loin. Steaks from Continental European Cross cattle and Low Choice carcasses had the lowest WBS values. Differences in consumer preparation of beef top loin steaks present very unique challenges for the beef industry. Consumer information programs may serve a valuable role in connecting consumer perceptions with the preparation techniques needed to consistently achieve satisfaction.     

Palatability of Meat from Mule Deer

To determine the palatability of meat from mule deer, a 10-member trained sensory panel evaluated meat from seven mule deer harvested in Texas. Beef rib roast and venison rib roast, loin steaks and semimembranosus steaks, and ground meat patties (beef, venison, venison/beef, and venison/pork) were evaluated. Venison contained much less fat than beef. Beef was more palatable than venison except for tenderness. The main difference in palatability was that venison was less juicy than beef. Mixing ground venison with beef or pork increased the palatability of venison to that of ground beef.     

Consumer Assessment of Beef Tenderloin Steaks from Various USDA Quality Grades at 3 Degrees of Doneness

A consumer study was conducted to determine palatability ratings of beef tenderloin steaks from USDA Choice, USDA Select, and USDA Select with marbling scores from Slight 50 to 100 (USDA High Select) cooked to various degrees of doneness. Steaks were randomly assigned to 1 of 3 degree of doneness categories: very‐rare, medium‐rare, or well‐done. Consumers (N = 315) were screened for preference of degree of doneness and fed 4 samples of their preferred doneness (a warm‐up and one from each USDA quality grade treatment in a random order). Consumers evaluated steaks on an 8‐point verbally anchored hedonic scale for tenderness, juiciness, flavor, and overall like as well as rated steaks as acceptable or unacceptable for all palatability traits. Quality grade had no effect (P > 0.05) on consumer ratings for tenderness, juiciness, flavor, and overall like scores, with all traits averaging above a 7 (“like very much”) on the 8‐point scale. In addition, no differences (P > 0.05) were found in the percentage of samples rated as acceptable for all palatability traits, with more than 94% of samples rated acceptable for each trait in all quality grades evaluated. Steaks cooked to well‐done had lower (P < 0.05) juiciness scores than steaks cooked to very‐rare or medium‐rare and were rated lower for tenderness (P < 0.05) than steaks cooked to a very‐rare degree of doneness. Results indicate consumers were not able to detect differences in tenderness, juiciness, flavor, or overall like among beef tenderloin steaks from USDA Choice and Select quality grades.     

Effects of cryogenic chilling on beef carcass grade, shrinkage and palatability characteristics

Alternate right or left sides of 90 carcasses were randomly selected and chilled at -70°C for 5 h, held at +16°C for 4 h and held at 1°C for 15 h (rapid chill-RC). The remaining sides were chilled at -7°C for 24 h (conventional chill-CC). Physical measurements and USDA quality grade data were obtained at 24 h post mortem and palatability samples were collected at 3-5 days post mortem. RC sides had 0·9% less shrinkage (P < 0·05) at 24 h post mortem when compared to paired CC sides. Beef sides that were given the RC treatment had a darker, softer lean (P < 0·01) and received higher marbling scores (P < 0·01) at 24 h post mortem than did CC sides. Loin steaks from RC sides had longer sarcomeres, less shear resistance and higher sensory panel tenderness ratings. It may be possible to rapidly chill carcasses with less carcass shrinkage and with no detrimental effects on USDA quality grade or on beef palatability.     

Effects of USDA feeder grade and time-on-feed on carcass characteristics and cooked beef palatability

Yearling feeder steers (n = 128), selected to vary in frame size and muscle thickness, were fed for 100, 130 or 160 days and then slaughtered. USDA grade data were collected and cooked rib steaks were evaluated for palatability attributes. Frame size was positively related to carcass weight and longissimus muscle area and negatively related to all fatness measures and to USDA yield grade. Steaks from large-framed steers received the lowest sensory panel ratings for juiciness and overall palatability. Muscle thickness of feeder steers was positively related to all measures of carcass muscling. Steaks from thinly muscled (No. 3) steers received higher ratings for juiciness and overall palatability than did steaks from thickly muscled (No. 1) steers. Large-framed or thickly muscled (No. 1) steers produced the lowest percentages of carcasses with at least Choice quality. Although some statistically significant differences were observed when the data were sorted by frame size or muscle thickness, few real trends were evident that would be of value to cattle feeders.     

Evaluation of an Accelerated Processing System for Precooked Beef Products

Twelve beef carcasses were used to determine the effects of accelerated processing (hot-boning) on cooking, palatability and storage characteristics of precooked beef products. The conventional (CS) and the accelerated processed (AS) sides were fabricated into rib roast, strip loin, chuck roll, and pizza topping and products were precooked by convection oven, broiling, water bath or in a steam kettle, respectively. Products from the AS sides had lower cooking losses for strip loin steaks and chuck rolls and shorter cooking times for loin steaks and rib roasts than did product from CS sides. Rib roasts and chuck rolls from both processing systems were very acceptable in tenderness, but AS loin steaks were unacceptable in tenderness. Loin steaks and rib roasts from AS had less off-flavor than roasts from CS sides.     

THE EFFECT OF ELECTRICAL STIMULATION ON THE PALATABILITY AND CONSUMER ACCEPTANCE OF BONELESS RIB STEAKS

A total of 25 cattle (5 purebred Simmental, Limousin, or Chianina bulls and 10 each of steers and heifers (1/2 blood Simmental, Limousin, or Chianina) 11 to 15 months of age and with carcasses weighing approximately 270 kg, after approximately 255 days on a high concentrate ration, were utilized to evaluate the effects of electrical stimulation upon the palatability and consumer acceptance of boneless rib steaks. The right side of each carcass was electrically stimulated at 400 V (AC 50 to 60 cycles/sec) using a hog stunner with a maximum output of 5 amps, immediately after splitting, while the left side served as an unstimulated control. Boneless rib steaks were presented to an experienced taste panel (1/side) and distributed to household consumers (4/side) for evaluation of overall tenderness and the acceptability of flavor, juiciness, tenderness, and overall palatability. Significant (P <0.05) treatment effects were not observed in cooking losses, consumer acceptance, or any of the palatability attributes evaluated, indicating that prerigor electrical stimulation, prior to chilling, did not produce meaningful differences in these traits, with the type of cattle and conditions employed in this study.     

CARCASS CHARACTERISTICS, SENSORY PROPERTIES AND MINERAL CONTENT OF MEAT FROM BULLS AND STEERS

Thirty-three bulls and 22 steers were slaughtered and subsequent carcasses were evaluated for carcass characteristics. Longissimus muscle samples were analyzed for sensory properties and concentrations of Cu, Fe and Zn. Bulls produced carcasses with older maturity characteristics, larger ribeyes, less fat and produced longissimus steaks that were less tender and had more organo-leptically detectable connective tissue than steaks from steers. Zn concentration was significantly correlated to skeletal maturity, fat thickness, ribeye area, connective tissue and tenderness before adjusting for sex. After adjusting for sex, mineral content did not significantly correlate as well with many carcass or sensory properties as before adjusting for sex.     

IDENTIFICATION OF THRESHOLD LEVELS FOR WARNER-BRATZLER SHEAR FORCE IN BEEF TOP LOIN STEAKS

Threshold Warner-Bratzler shear (WBS) values were determined by regression analysis of WBS force values and trained sensory panel overall tenderness ratings of beef top loin steaks from A- and B-maturity carcasses (n = 678). Guidelines for retail and foodservice beef were based on 50 and 68% confidence levels, respectively, for overall tenderness ratings of "slightly tender." Due to the extreme variation in tenderness that exists in the current U.S. beef population, more stringent confidence levels were not practical. Threshold WBS values for retail and foodservice beef were 4.6 and 3.9 kg, respectively. When these values were tested against the population of beef in the National Consumer Retail Beef Study, the 4.6 kg value was 88.6% accurate at determining whether or not a steak would be rated less than "slightly tender"by consumers.     

Effects of teeth maturity and fatness of Nellore (Bos indicus) steer carcasses on instrumental and sensory tenderness

This study sought to evaluate the effects of teeth maturity and carcass fatness on physical and sensory traits of the beef ribeye (M. longissimus thoracis). Carcass sides (n = 60) of Nellore steers were grouped into six categories, according to teeth maturity (2, 4 and 6 permanent incisors), and fatness (2 – slight and 3 – average). The boneless ribeye cuts (6th – 9th ribs) were vacuum packed and aged for 14 days. Steaks, 2.5 cm thick, were evaluated as to sarcomere length, shear force and sensory attributes. Sarcomere length was not affected (P > 0.05) by maturity or fatness. Teeth maturity did not influence (P > 0.05) tenderness measured by instrumental or sensory analysis, however rib steaks from fatter carcasses displayed better tenderness (P < 0.01) and lower cooking losses (P < 0.01). In the Nellore steer carcasses produced in Brazil, fatness may be more important than teeth maturity to improve meat tenderness.     

Effects of Hot-Boning and Particle Thickness on Restructured Beef Steaks

Restructured steaks were made using hot-boned or aged beef made from sliced particles (2.5 mm or 5.0 mm thick). Beef slices were formed to make restructured steaks. The steaks were evaluated for cooking characteristics, textural properties and sensory attributes. Restructured steaks made from hot-boned beef were generally considered less tender and received lower texture desirability, flavor desirability and overall palatability ratings as compared to steaks made from aged beef. Restructured steaks made from larger meat slices (5.0 mm) were less tender and received lower texture desirability ratings than restructured steaks made with thinner slices (2.5 mm).