Top Sirloin Steaks Research Articles

Canadian beef tenderness survey: 2001–2011

Juárez, M., Larsen, I. L., Klassen, M. and Aalhus, J. L. 2013. Canadian beef tenderness survey: 2001–2011. Can. J. Anim. Sci. 93: 89–97. A large survey across Canada was developed collecting retail beef samples in 2001 (702 steaks) and 2011 (602 steaks). The samples (strip loin, top sirloin, inside round and cross-rib steaks) were evaluated for instrumental tenderness using standard procedures for sampling, storage, cooking and texture evaluation. New equations were also developed in order to compare the results obtained in these studies with consumer thresholds developed in Canada and the United States of America. In general, retail steaks collected in 2011 weighed less and showed higher fat thickness than those from 2001. Regarding tenderness, a significant improvement was observed, especially for strip loin and top sirloin steaks between 2001 and 2011. Using US threshold categories, the percentage of “tender” samples improved for the strip loin (2001=89%; 2011=99%), top sirloin (2001=70%; 2011=87%), inside round (2001=52%; 2011=61%) and cross-rib (2001=65%; 2011=76%) steaks. Similarly, the percentage of “tough” samples shifted from 5, 8 27 and 13% for the strip loin, top sirloin, inside round and cross-rib steaks in 2001 to 1, 5, 13, and 8%, respectively, in 2011. Similar improvements were observed when using the more descriptive four-category Canadian threshold system. These improvements may be due to changes in the animal population, production systems, carcass processing and distribution/handling prior to display in Canada.

National Beef Tenderness Survey–2010: Warner-Bratzler shear force values and sensory panel ratings for beef steaks from United States retail and food service establishments1

The tenderness and palatability of retail and food service beef steaks from across the United States (12 cities for retail, 5 cities for food service) were evaluated using Warner-Bratzler shear (WBS) and consumer sensory panels. Subprimal postfabrication storage or aging times at retail establishments averaged 20.5 d with a range of 1 to 358 d, whereas postfabrication times at the food service level revealed an average time of 28.1 d with a range of 9 to 67 d. Approximately 64% of retail steaks were labeled with a packer/processor or store brand. For retail, top blade had among the lowest (P < 0.05) WBS values, whereas steaks from the round had the greatest (P < 0.05) values. There were no differences (P > 0.05) in WBS values between moist-heat and dry-heat cookery methods for the top round and bottom round steaks or between enhanced (contained salt or phosphate solution) or nonenhanced steaks. Food service top loin and rib eye steaks had the lowest (P < 0.05) WBS values compared with top sirloin steaks. Retail top blade steaks and food service top loin steaks received among the greatest (P < 0.05) consumer sensory panel ratings compared with the other steaks evaluated. Prime food service rib eye steaks received the greatest ratings (P < 0.05) for overall like, like tenderness, tenderness level, like juiciness, and juiciness level, whereas ungraded rib eye steaks received the lowest ratings (P < 0.05) for like tenderness and tenderness level. The WBS values for food service steaks were greater (P < 0.05) for the Select and ungraded groups compared with the Prime, Top Choice, and Low Choice groups. The WBS values and sensory ratings were comparable to the last survey, signifying that no recent or substantive changes in tenderness have occurred.

Dry versus wet aging of beef: Retail cutting yields and consumer sensory attribute evaluations of steaks from ribeyes, strip loins, and top sirloins from two quality grade groups

Top Choice ( n = 48) and Select ( n = 48) paired bone-in ribeye rolls, bone-in strip loins, and boneless top sirloin butts were assigned randomly to one of two aging treatments, dry or wet, and were aged for 14, 21, 28 or 35 d. Cutting tests, performed to determine retail yields and processing times, showed dry-aged subprimals had lower total saleable yield percentages and increased processing times compared to wet-aged subprimals. Sensory and Warner–Bratzler shear evaluation was conducted to determine palatability characteristics. For the most part, aging treatment and aging period did not affect consumer sensory attributes. However, ribeye and top loin steaks from the Top Choice quality grade group received higher sensory ratings than their Select counterparts. For top sirloin steaks, no consumer sensory attributes were affected by aging treatment, aging period, or quality grade group.

Beef customer satisfaction: Factors affecting consumer evaluations of calcium chloride-injected top sirloin steaks when given instructions for preparation1

The objectives of this study were to evaluate whether instructions can help consumers properly prepare top sirloin steaks and to evaluate the use of calcium chloride injection to decrease the sensitivity of top sirloin steaks to degree of doneness, thereby improving customer satisfaction ratings. An in-home study evaluated top sirloin steaks (gluteus medius) as influenced by calcium chloride injection (injected vs. noninjected), consumer segment (beef loyalists = heavy consumers of beef, budget rotators = cost-driven and split meat consumption between beef and chicken, and variety rotators = higher incomes and education and split meat consumption among beef, poultry, and other foods), degree of doneness, cooking method, and instructions (given vs. not given). Consumers evaluated overall like, tenderness, juiciness, flavor like, and flavor amount using 10-point scales. Beef loyalists consistently rated steaks higher for overall like, juiciness, and flavor when instructions were provided (P < 0.05) and rated top sirloin steaks higher for overall like and tenderness when given instructions for grilling (P < 0.05). Budget rotators and variety rotators rated steaks differently among cooking methods (P < 0.05). Correlation and stepwise regression analyses indicated that flavor like was the most highly correlated with overall like, followed by tenderness, flavor amount, and juiciness. Calcium chloride injection had no effect on consumers' likes or dislikes or on tenderness (P < 0.05). For top sirloin steaks, it was likely that preparation played a major role in consumer satisfaction, and beef loyalists benefited the most from providing cooking instructions.

Flavor characterization of top-blade, top-sirloin, and tenderloin steaks as affected by pH, maturity, and marbling1,2,3

Little information is available in the literature on the interrelationships and interactions among pH, aging time, marbling, and maturity on the flavor profile of some beef muscles commonly used for steaks. To investigate these effects on beef flavor, the infraspinatus (top-blade steak) from the chuck clod, the gluteus medius (top-sirloin steak) from the sirloin, and the psoas major (tenderloin steak) from the loin were obtained from A- (n = 80) and B-maturity (n = 60) carcasses with either Slight (n = 68) or Small (n = 72) marbling, and with either normal (< or = 5.7; n = 80) or high (> or = 6.0; n = 60) pH. Muscles were selected from two commercial processing plants at six different sampling times to evaluate factors that affect the flavor profile of cooked beef steaks. Muscles were vacuum-aged for 7, 14, 21, or 35 d, and a highly trained, flavor-profile sensory panel evaluated charbroiled steaks from these muscles. Numerous statistical interactions (P < 0.05) were detected for flavor attributes of the different muscles. In general, muscles from high pH (dark cutting) carcasses had less typical beef flavor identity and less brown-roasted flavor than those from carcasses with normal pH. Aging longer than 21 d generally decreased beef flavor identity. Top-blade steaks generally had less intense beef flavor identity and more intense bloody/serumy flavor than did top-sirloin and tenderloin steaks. Tenderloin and top-sirloin steaks of normal pH generally had the most brown-roasted flavor, especially when aged 21 d or less. Small degree of marbling generally resulted in a more rancid flavor compared with Slight marbling, but marbling had no other appreciable effects on the flavor profile. Aging steaks for 35 d increased (P < 0.05) the metallic flavor compared with aging for only 7 or 14 d. Top-sirloin steaks had a more intense (P < 0.05) sour flavor than did top-blade steaks, and steaks from carcasses with a high pH were more rancid (P < 0.05) than steaks from carcasses with normal pH. Vacuum-aging top-blade, top-sirloin, and tenderloin steaks to 21 or 35 d postmortem generally increased metallic and rancid flavors and increased sour flavor in top-sirloin steaks that were high in pH.

Color and thiobarbituric acid values of cooked top sirloin steaks packaged in modified atmospheres of 80% oxygen, or 0.4% carbon monoxide, or vacuum

Case-ready fresh beef is typically packaged in a modified-atmosphere with approximately 80% oxygen and 20% carbon dioxide. Recently, USDA approved distribution of fresh meats in a master bag system using 0.4% carbon monoxide (CO). This study compared effects of packaging system (vacuum, 80% oxygen, 0.4% carbon monoxide), fresh meat storage time (7–21 days) and cooking temperature (49–79 °C) on extent of myoglobin denaturation, color and rancidity in cooked top sirloin steaks. Steaks packaged in 80% oxygen or CO retained desirable red color for 14 and 21 days storage, respectively. Steaks stored in 80% oxygen exhibited the greatest TBA values and myoglobin denaturation at all storage times and cooking temperatures. Steaks stored in high oxygen developed brown interior color at internal temperatures as low as 57 °C, the premature browning effect. Premature browning and rancidity associated with steaks packaged in 80% oxygen was prevented by packaging in 0.4% CO or vacuum.

Beef customer satisfaction: trained sensory panel ratings and Warner-Bratzler shear force values.

Trained sensory panel ratings and Warner-Bratzler shear force (WBS) values from the Beef Customer Satisfaction study are reported. Carcasses were chosen to fit into USDA quality grades of Top Choice (upper two-thirds of USDA Choice), Low Choice, High Select, and Low Select. A trained, descriptive attribute panel evaluated top loin, top sirloin, and top round steaks for muscle fiber tenderness, connective tissue amount, overall tenderness, juiciness, flavor intensity, cooked beef flavor intensity, and cooked beef fat flavor intensity. Four steaks from each of the three cuts from each carcass were assigned randomly to one of four cooking endpoint temperature treatments (60, 65, 70, or 75 degrees C) for WBS determination. For all trained panel measures of tenderness and WBS, regardless of USDA quality grade, top loin steaks were rated higher than top sirloin steaks, which were rated higher than top round steaks (P < 0.05). There were significant interactions between USDA quality grade and cut for most of the trained sensory panel traits: USDA quality grade influenced ratings for top loin steaks more than ratings for top round steaks or top sirloin steaks. Three interactions were significant for WBS values: USDA quality grade x endpoint temperature (P = 0.02), USDA quality grade x cut (P = 0.0007), and cut x endpoint temperature (P = 0.0001). With the exception of High Select, WBS values increased (P < 0.05) for each grade with increasing endpoint temperature. Choice top loin and top round steaks had lower (P < 0.05) WBS values than Select steaks of the same cut; however, only Top Choice top sirloin steaks differed (P < 0.05) from the other USDA grades. As endpoint temperatures increased, WBS values for top sirloin steaks increased substantially compared to the other cuts. When cooked to 60 degrees C, top sirloin steaks were closer to top loin steaks in WBS values, when cooked to 75 degrees C, top sirloin steaks were closer to top round steaks in WBS values. Simple correlation coefficients between consumer ratings and trained sensory muscle fiber tenderness, connective tissue amount, overall tenderness, juiciness, flavor intensity, and cooked beef fat flavor were significant (P < 0.05), but values were low. While relationships exist between consumer and trained sensory measures, it is difficult to predict from objective data how consumers will rate meat at home.

Flavor characterization of top blade, top sirloin, and tenderloin steaks from A- and B-maturity carcasses of high and normal pH (2003)

The infraspinatus muscle (top blade steak) from the chuck clod, the gluteus medius muscle (top sirloin steak) from the sirloin, and the psoas major muscle (tenderloin steak) from the loin were obtained from A- and B-maturity carcasses with either low-Slight or Small marbling and with either normal ultimate pH (5.7 or less) or high pH (6.0 or higher) to evaluate flavor profile characteristics. Muscles were aged for 7, 14, 21, and 35 days. A highly trained flavor-profile sensory panel evaluated charbroiled steaks from these muscles. Muscles from high pH (dark cutting) carcasses had less typical beef flavor identity and less brown roasted flavor than those from carcasses with normal pH. Top blade steaks had a more intense bloody/serumy flavor than top sirloin and tenderloin steaks. Aging steaks to 21 or 35 days postmortem increased the metallic flavor sensory characteristic. Top sirloin steaks had a more intense sour flavor than top blade or tenderloin steaks, and steaks from carcasses having a high pH were found to be more rancid than those from carcasses with normal pH. In general, high pH steaks and those aged longer than 21 days had less desirable flavor profiles than normal pH steaks and those aged only 14 days.

Effects of three levels of alpha-tocopheryl acetate supplementation to feedlot cattle on performance of beef cuts during retail display.

Retail packages (n = 288; 24 of each product in each treatment group) of inside round steaks, T-bone steaks (strip loin and tenderloin), top sirloin steaks, and ground beef were used to evaluate effects of dietary supplementation of vitamin E to cattle on product performance during retail display. Products from control animals and cattle fed 500 IU x animal(-1) x d(-1) or 1,000 IU x animal(-1) x d(-1) were evaluated. Except for ground beef, dietary supplementation of vitamin E increased (P < 0.05) alpha-tocopherol concentrations in beef muscle from cattle fed 1,000 IU x animal(-1) x d(-1). Although not all differences were statistically significant, retail display-life was greater for all steaks from cattle fed 1,000 IU x animal(-1) x d(-1) than for those from control cattle. Ten percent of the inside round and tenderloin steaks from cattle fed 1,000 IU x animal(-1) x d(-1) had mean overall appearance scores of 3 ("moderately undesirable") at 72 to 78 h and 54 to 60 h, respectively, whereas 10% of the inside round and tenderloin steaks from control cattle had mean overall appearance scores of 3 at 54 to 60 h and 42 to 48 h, respectively. Each of the retail cuts in this study (irrespective of the amount of alpha-tocopheryl acetate that was fed to the animal that generated it) was categorized as "high," "medium," or "low," based on the alpha-tocopherol concentration in the primal cut or ground beef batch from which it originated. Retail cuts in the medium a-tocopherol concentration category had increased retail display life of 4.0 h for ground beef (P < 0.05) over those in the low alpha-tocopherol category. Retail cuts in the high alpha-tocopherol concentration category had increased retail display life of 10.7 h for inside round steaks and 4.0 h for ground beef (P < 0.05) over those in the medium concentration category. Vitamin E supplementation of cattle at 1,000 IU x animal(-1) x d(-1) for at least 100 d can be used to increase retail caselife and to improve the overall color acceptability of steaks and ground beef products. Although far from a perfect relationship, these data strongly suggest that increasing the alpha-tocopherol concentration in a beef cut will increase its retail case life.

Tenderness and cooking characteristics of beef cooked by electric belt grill, forced-air convection oven, or electric broiler (2001)

We used an electric belt grill, a forced-air convection oven, and an electric broiler to cook 170 bottom round, 142 brisket, 177 top sirloin, 176 strip loin, and 136 eye of round steaks from USDA Select carcasses to determine the effects of cooking method and muscle on shear force values, cooking traits, and repeatability of duplicate measurements. All cooking treatments allowed differences to be detected (P<0.05) in Warner-Bratzler shear force, although the differences were inconsistent. Shear force values of strip steaks and eye of round steaks were similar across cooking treatments; however, shear force values of bottom round, brisket, and top sirloin steaks were different (P<0.05) among cooking treatments. Based on poor repeatability, shear force values for top sirloin steaks appear unreliable. Poor repeatability for shear force values from steaks cooked by the forced-air convection oven are a result of drastic temperature changes that occur when the doors are opened to remove steaks. We do not recommend using a forced-air convection oven to test treatment effects on shear force values when cooking multiple steaks simultaneously. Belt grill cooking resulted in the highest shear force repeatability R = 0.07 to 0.89) of strip steaks. Electric broiling resulted in acceptable R = 0.60) repeatability of shear force measurements for all classes of steaks. The electric broiler and electric belt grill are both satisfactory cooking methods when measuring shear force of bottom round, brisket, strip loin, and eye of round steaks.

Palatability of beef steaks marinated with solutions of calcium chloride, phosphate, and (or) beef-flavoring

This study evaluated the efficacy of marination for increasing consumer acceptability of beef. Top-sirloin steaks from 28 USDA select steers were randomly assigned to one of six marination treatments: control (CT), 150 mM calcium chloride (CA), 10% solution of beef-flavoring/seasoning mixture (FL), CA and FL (CF), 2.5% sodium phosphate and FL (PF), and tap water (TW). Steaks were marinated in vacuum pouches, aged for 7 days, cooked to 70°C and evaluated by a trained sensory panel. Marination with CA did not affect tenderness ratings, but increased ( P<0 .05) bitter and metallic flavors compared to CT or TW treatments. Use of FL, alone or in conjunction with CA or sodium phosphate, increased ( P<0.05) tenderness and juiciness ratings and reduced ( P<0.05) bitterness and metallic flavors compared to CT, CA and TW marinades. Marination of beef, in vacuum pouches, is an effective method for increasing consumer acceptability and value beef.

New approaches for improving tenderness, quality, and consistency of beef

In an effort to increase U.S. domestic beef demand, beef industry leaders have recommended the development and implementation of Total Quality Management-like systems to enhance product quality and consistency. This review outlines the application of quality management practices and process control to improve tenderness and quality of beef. Adoption of a quality management philosophy for improvement of product quality requires a shift of focus from issues of greatest concern to producers to issues that are of greatest concern to consumers. Development of “alliances” and branded beef programs, in which producers maintain some share of ownership through the entire production/marketing chain helps shift producer focus to issues that are important to consumers, provides a clearer economic signal encouraging improvement of product quality, and provides an opportunity for the application of quality management principles to facilitate the improvement of beef quality. Application of a quality management system for improving beef tenderness and quality requires identification of “control points” and application of process control to prevent quality shortfalls, verification of conformance to specifications for tenderness/quality, and identification of methods for improving tenderness and quality attributes of nonconforming products. A prototype quality management system for ensuring beef tenderness is described. This prototype system involves four “control points” (genetic inputs, preslaughter cattle management, early postmortem management, and postmortem aging) at which inputs/processes are controlled to improve tenderness, a verification step based on a tenderness measurement obtained at 1 to 3 d postmortem, and the use of tenderization technologies to improve tenderness of nonconforming products. Application of the prototype system reduced the expected rate of nonconformance to tenderness specifications from about one in four, for both top sirloin steaks and strip loin steaks, to about 1 in 25 and 1 in 100 for top sirloin steaks and strip loin steaks, respectively. Use of process control in a quality management system may be an effective approach for improving the tenderness and quality of beef.

National Beef Tenderness Survey-1998.

Fifty-six retail stores representing 15 retail chains and 14 foodservice facilities in eight U.S. cities were sampled to determine the tenderness of beef steaks at retail and foodservice levels based on Warner-Bratzler shear (WBS) values and consumer evaluation panels. Retail consumer panels were conducted at five universities. Each retail and foodservice steak was evaluated using 10-point scales. Steaks were divided into the following quality groups for statistical analysis: Prime, Top Choice, Choice, Select, and Lean or No Roll. Quality group had no effect on WBS values of retail clod, chuck roll, top round, bottom round, eye of round, top loin, top sirloin, or ribeye steaks but did (P < .05) affect values for the T-bone/porterhouse. The percentages of retail top round, eye of round, and bottom round steaks with a WBS force > 3.9 kg were 39.6, 55.9, and 68.0, respectively. Foodservice ribeye, top loin, and top sirloin steaks had WBS values less than 3.4 kg for all quality groups, with Prime ribeye steaks having lower (P < .05) WBS values than ribeyes from the other quality groups. With the exception of the retail ribeye steak, quality group did not affect consumer sensory ratings of retail and foodservice steaks. Average postfabrication aging times were 32 d for foodservice subprimals and 19 d for retail cut subprimals. These data indicate that improvements in the tenderness of retail cuts from the round are needed. Finally, quality group had little or no effect on consumer sensory evaluations and WBS values of retail and foodservice steaks used in this study.

Beef customer satisfaction: cooking method and degree of doneness effects on the top sirloin steak.

The objective of this research was to evaluate the consumer-controlled factors of cooking method and degree of doneness on Top Choice, Low Choice, High Select, and Low Select top sirloin steaks. The in-home product test was conducted in Chicago, Houston, Philadelphia, and San Francisco. Consumers (n = 2,212) evaluated each top sirloin steak for overall like (OLIKE), tenderness (TEND), juiciness (JUIC), flavor desirability (DFLAV), and flavor intensity (IFLAV) using 23-point hedonic scales. Top sirloin steaks, regardless of city, were consistently cooked to well done or higher degrees of doneness. Dry-heat methods such as outdoor grilling, broiling, and indoor grilling were the most frequent cooking methods used. Four significant interactions existed for OLIKE: USDA quality grade x cooking method (P = .02), city x cooking method (P = .0001), city x degree of doneness (P = .01), and cooking method x degree of doneness (P = .009). Greater differences were found between cooking methods within USDA quality grade than between USDA quality grades within cooking method. Consumers in Houston rated steaks cooked by outdoor grilling higher than those from the other cities, and steaks cooked by indoor grilling were rated the highest among all cooking methods by consumers in Chicago. In Chicago, steaks cooked to more advanced degrees of doneness tended to receive higher ratings, but few differences between degrees of doneness in the other three cities were detected. For outdoor grilling, broiling, and pan-frying, the trend was for OLIKE ratings to decline as degree of doneness increased. The lowest customer satisfaction ratings tended to be given to top sirloin steaks cooked to more advanced degrees of doneness, and consumers most frequently cooked steaks to at least the well done stage. Consumer information programs or the development of postmortem techniques that would ensure acceptable palatability of top sirloin steaks may need to be developed.

An audit of retail beef loin steak tenderness conducted in eight U.S. cities.

An audit of supermarkets in eight U.S. cities was conducted to characterize retail beef loin steaks with respect to grade, postfabrication aging, and tenderness and to provide an interim measure of progress in industry efforts to improve retail beef tenderness. Top sirloin steaks (n = 819) and strip loin steaks (n = 827 paired steaks) were purchased at retail markets in Atlanta, Chicago, Denver, Houston, Philadelphia, Phoenix, San Francisco, and Seattle and shipped to Colorado State University for measurement of shear force (both cut types) and evaluation by a trained sensory panel (strip loins only). Approximately 80% of the steaks originated from beef plants in Kansas, Texas, Nebraska, and Colorado. Postfabrication aging periods ranged from 2 to 87 d (mean = 20.8 d) for top sirloin steaks and from 2 to 91 d (mean = 19.2 d) for strip loin steaks, although most top sirloin (85%) and strip loin (91%) steaks were available for purchase 7 to 35 d after fabrication. The mix of quality grades was similar for both cuts: 60% Select, 31% "commodity" Choice, 6 to 7% "Certified" Choice, and 2 to 3% Prime. Shear force averaged 3.46 kg (SD = .74) for top sirloins and 3.05 kg (SD = .95) for strip loins; 75% of both steak types had shear force values between 2 and 4 kg. Postfabrication periods shorter than 7 d were associated with reduced (P < .05) tenderness, especially for top sirloin steaks. Higher quality grades were associated with greater (P < .05) tenderness (Prime > Choice > Select) for both cuts. Based on panel tenderness ratings, the approximate odds of obtaining a "slightly tough" or tougher strip loin steak at a retail supermarket were: 0 for Prime, 1 in 10 for "Certified" Choice, 1 in 5 for "commodity" Choice, and 1 in 4 for Select. Audit results suggest that tenderness characteristics of loin steaks have not changed materially since the National Beef Tenderness Survey was conducted in 1991 and that two primary focal points of the beef industry's efforts to improve tenderness should be 1) to prevent short-aged (< 7 d postfabrication) product from reaching consumers and 2) to identify methods for enhancing tenderness of Select and "commodity" Choice beef.

Calcium-activated tenderization of strip loin, top sirloin, and top round steaks in diverse genotypes of cattle.

Steers of known percentage Brahman (B) and Angus (A) breeding (100% A, n = 6; F1 B x A, n = 6; and 100% B, n = 6) were used to determine the effect of calcium chloride injection on the calpain proteinase system and meat tenderness. The steers were slaughtered in six replications (at either 9 or 14 mm of backfat, determined ultrasonically), with each breed type represented. Calpains and calpastatin activities were measured on fresh, prerigor longissimus muscle samples. Carcass data were collected after a 24-h chill, and the short loin (IMPS #180), top sirloin (IMPS #184), and top round (IMPS #168) were removed from both sides of each carcass. The cuts from the right side were then injected at 5% (wt/wt) with CaCl2 solution (2.2%). Longissimus muscle calpain and calpastatin activities were also measured at 48 h postmortem from the injected and control sides of each carcass. Warner-Bratzler shear force was measured on steaks from the three subprimals aged 1, 2, 5, 15, or 31 d. Marbling scores and USDA quality grades were higher (P<.05) in A than in F1 B x A and B carcasses. Calpastatin activity was higher (P<.05) in muscle from B than in muscle from A and F1 B x A steers, and postmortem storage (O vs 48 h) and CaCl2 injection reduced (P<.05) the activity of the calpains and calpastatin. Strip loin and top sirloin steaks from A and F1 B x A steers were more tender (P<.05) than steaks from B steers; however, top round steak tenderness did not differ (P>.05) across breed type. Calcium injection improved strip loin and top sirloin steak tenderness, but it did not affect top round steak tenderness. Collectively, these data show that CaC12 injection can be used to improve meat tenderness, with similar responses shown in cattle containing 0, 50, and 100% B inheritance. However, even with CaCl2 injection, B steaks are less tender than their A and F1 B x A counterparts.

QUALITY GRADE, PORTION SIZE, NEEDLE TENDERIZATION AND COOKERY METHOD EFFECTS ON COOKING CHARACTERISTICS AND PALATABILITY TRAITS OF PORTIONED STRIP LOIN AND TOP SIRLOIN STEAKS

Strip Loin (IMP # 1180A) and Top Sirloin Center Cut steaks (IMP # 1184B) purchased from a foodservice purveyor and aged 21 days were used to evaluate cookery method, needle tenderization, quality grade and portion size effects on palatability and cooking characteristics. Both steak types were distributed across 4 quality grade classes (USDA Select = S, USDA Choice = C, USDA Prime = P, and Certified Angus BeefTM= UC), 2 portion sizes (strip loins, 283 and 397 g; top sirloins, 255 and 340 g), 2 tenderization treatments (needle tenderized = T and nontenderized = NT) and 2 cooking methods (Clamshell® broiler-grill = CS and electric grill = FW). Cook time/100 g was lower (P 0.05) sensory tenderness in the strips or sirloin steaks. Sensory tenderness scores were lower (P 0.05) sensory tenderness in the strips steaks but improved sensory tenderness scores in the sirloin steaks. A needle tenderization by quality class interaction in the sirloins showed that T steaks from the S, C and UC classes were more tender than NT steaks; however, tenderization did not affect tenderness of P steaks. Collectively these data suggest that rapid cookery systems (i.e., Clamshell®) can reduce cooking time in portioned foodservice strip and top sirloin steaks without detrimental effects on palatability.

SUPPLEMENTATION OF VITAMIN E TO BOVINE FEMALES IN “WHITE COW”, MATURE BEEF, UPGRADING PROGRAMS

ABSTRACT Forty cull cows were used to determine the effects of feeding supplemental dietary Vitamin E and a high‐concentrate feedlot finishing diet on fresh meat retail caselife and oxidized flavor of roast beef from carcasses of such cows. They were either fed a feedlot finishing diet not supplemented with Vitamin E (control; N=8) or were fed a feedlot finishing diet supplemented with Vitamin E for 14, 28, 42 or 56 days (N=8 for each time‐on‐feed). During the feeding period, the 32 cows in treatment feeding groups had access to a total of 50,400 IU of supplemental Vitamin E; cows in the 14 day time‐on‐feed group received the highest daily dose (3,600 IU/day) and those in the 56 day time‐on‐feed group received the lowest daily dose (900 IU/day) of supplemental Vitamin E. On average, tissue α‐tocopherol levels were increased from 2.39 μg/g (control) to 4.21–5.44 μg/g by 14–56 days of supplemental feeding. Supplemental feeding of dietary Vitamin E and a feedlot finishing diet had the greatest effect on the visual color and percent surface discoloration of top round and top sirloin steaks and had the least effect on the visual color and percentage surface discoloration of ground beef patties, tenderloin and strip steaks. Taste panelists were able to detect a slightly, but significantly, greater quantity of warmed‐over flavor components in the control roast beef than in the roast beef from cattle fed supplemental dietary Vitamin E and a feedlot finishing diet.

FACTORS AFFECTING PURGE LOSSES IN PORTION CONTROLLED STEAKS

Weight losses, as purge, and pH were monitored during storage of strip loin, tenderloin, and top sirloin steaks to investigate factors that affect purge losses in portion controlled steaks. Purge losses and pH were monitored over time (6, 10, 14, 18, 22 and 26 days), across temperature and in individual and multiple steak packages (strip loin, n = 4; tenderloin, n = 7; top sirloin, n = 10). Top sirloin steaks had the greatest purge loss (%) and strip loin steaks had the lowest purge loss (%) across all treatments. In general, purge losses (%) increased and pH decreased during storage of all three steak types; however, storage temperature did not influence (P >0.10) purge loss. Total purge loss and purge loss as a percent of steak weight was significantly higher (P < 0.05) in multiple steak packages as compared to single steak packages. Correlations between the number of steaks in a package and purge losses were highly significant (P < 0.001) across all three steak types. Within a steak type, the number of steaks in a package explained 59, 75 and 89% of the variation in total purge losses in strip loin, tenderloin, and top sirloin steaks, respectively. Across all steak types, total purge loss increased quadratically as package weight increased (R2=0.89) emphasizing a greater total purge loss per steak in the multiple steak packages than in the individual steak packages. These data suggest that package size (steak number) has a greater influence on the amount of purge in portion sized strip loin, tenderloin and top sirloin steaks than storage time or storage temperature.

Incidence and sensory evaluation of injection-site lesions in beef top sirloin butts.

The effects of ongoing quality assurance initiatives on the national incidence of injection-site lesions and the impact of these lesions on the sensory characteristics of top sirloin butts were examined by a series of audits and two experiments. The national incidence of injection-site lesions in top sirloin butts (n = 98,192) has not changed between July 1993 (10.91%) and July 1995 (10.19%). However, during this same period, the mean weight of injection-site lesion trim increased (P < .05) from 102.63 +/- 12.56 g to 152.81 +/- 13.24 g. Eighty percent of lesions examined during this period were classified as chronologically "older," originating from injections given either during preweaning, stocking, or in the early feeding period; however, there was an increase (P < .01) in the incidence of nodular scars during the audit period, likely created by intramuscular injections during the mid- to late-feeding periods. Warner-Bratzler shear measurements of lesion-afflicted steaks taken near the site of lesions and in areas up to 7.62 cm from the lesion center were significantly greater than similar measurements on control top sirloin steaks. Panelist tenderness scores for mildly lesioned steaks were lower (P < .05) and had greater within-(P < .01) and among- (P < .05) steak variation than control (normal) steaks. Mean juiciness ratings were higher (P < .001) for lesioned steaks; however, steak flavor intensity variation was greater within injection-site lesioned vs control top sirloin steaks, with undesirable flavors reported by panelists. Injection-site lesions still occur at an unacceptable frequency in the top sirloin butt, and those lesions, if not removed entirely, can dramatically reduce the desirability of top sirloin steaks.