Round Steaks Research Articles

Effects of low voltage electrical stimulation on quality characteristics of young bulls fed to 14, 16 and 18 months of age (1984)

Low voltage electrical stimulation of young bulls at 30 to 45 min after bleeding resulted in a lower muscle pH, higher marbling score, lighter cherry red color and reduced incidence of heat ring formation when compared to non-stimulated controls. Ribeye steaks from electrically stimulated sides were more tender than non-stimulated controls, but bottom round steaks were not different. Our results indicate that low voltage electrical stimulation, incorporated into a continuous slaughter operation as late as 30 to 45 min after bleeding, can improve USDA quality characteristics and tenderness of meat from young bulls.

Effect of Growth of Individual Meat Bacteria on pH, Color and Odor of Aseptically Prepared Vacuum-Packaged Round Steaks

Large increases in counts cf Leuconostoc spp., Lactobacillus coryneformis, Lactobacillus plantarum, Lactobacillus viridescens and Lactobacillus curvatus occurred over a 28-d display period when aseptically fabricated steaks were inoculated with 103 to 104 cells/cm2 of these species and then were vacuum-packaged. With Lactobacillus cellobiosus 2, Serratia liquefaciens or Hafnia alvei as inoculum, increases in count were much smaller. Counts of L. cellobiosus 1, Brochothrix thermosphacta, a Moraxella sp. and Alteromonas putrefaciens of inoculated steaks decreased during display. With a higher inoculum (106 cells/cm2), increases in counts of lactic acid bacteria usually were smaller. Some lactic acid bacteria caused marked decreases (0.2 to 0.5) in the pH of the meat surface. Changes in surface discoloration of uninoculated and inoculated steaks over a 28-d display period were not significant (P>0.05). Off-odor scores of both uninoculated and inoculated steaks were lower (more off-odor) after display but few of the differences were significant. Off-odors of steaks inoculated with lactic acid bacteria were described as “sour”, “buttermilk”, “sulfur-like” and “H2S”.

Physical and Sensory Characteristics of Vacuum Packaged Beef Round Steaks as Influenced by Postmortem Age and Storage Temperature

ABSTRACTTwo steaks were removed from the semitendinosus, semimembranosus and biceps femoris muscles at 3, 6 or 9 days postmortem and vacuum packaged. Steaks were stored for 48 hr at 2°C or 7°C before retail display. Steaks cut at 3 days had less (P < 0.05) surface discoloration than those removed at 6 or 9 days. In most comparisons, steaks removed at 3 days were more desirable (P < 0.05) in overall appearance than steaks removed at either 6 or 9 days and stored at either temperature. Storage temperature did not accelerate lean color development for vacuum packaged beef round steaks. With increasing time postmortem before fabrication into steaks, longer storage periods may be needed before display to allow devet opment of proper lean color.

Relationship of USDA Maturity Groups to Palatability of Cooked Beef

ABSTRACTIn 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.

EFFECT OF PRESSING ON MOISTURE LOSS AND SENSORY PROPERTIES OF BEEF

ABSTRACTPaired halves of top round (Semimembranosus and Adductor muscles) sub‐primals were removed from each of ten, USDA Choice, approximately 272 kg steers, freezer wrapped, frozen, and stored at ‐24° C for approximately 1 month. Following freeze‐tempering, each primal was divided longitudinally with one half being pressed at 344 Newtons/cm2 to a specified shape in a Bettcher Model 70 Press, while the other half served as nonpressed control. Moisture loss and sensory properties were determined for 2.54 cm thick steaks. No significant differences were found in juiciness, flavor or Kramer shear values between pressed and non‐pressed top round steaks, however, sensory tenderness scores were lower (P < 0.05) for steaks that were pressed than for those that were not pressed. Holding steaks at 2° C for 0, 1, 2, or 3 days did not significantly alter Kramer shear or sensory panel evaluations. Cooking loss, drip loss and total loss were not affected by pressing. Drip loss was lower (P < 0.05) and cooking loss was higher (P < 0.05) for steaks held one day at 2° C than for steaks held 2 or 3 days at 2° C. When drip loss and cooking loss were combined (total loss) there was no difference among the four storage times. Drip loss following portion cutting could result in a problem in fresh merchandising of freeze‐tempered cuts.

Tenderness Improvement of the Major Muscles of the Beef Carcass by Electrical Stimulation

ABSTRACTSteaks (arm; blade; seven‐bone; rib, small‐end; top loin; tenderloin; top sirloin; tip, cap‐off; and round) from electrically stimulated (ES) and control sides of 20 beef carcasses were cut and frozen at 5 days postmortem. Forequarter muscles that were improved by ES were the longissimus dorsi (rib steak), the subscapularis and supraspinatus (blade steak), and the superficial pectoral (arm steak). Hindquarter muscles that were improved by ES were the longissimus dorsi (top loin steak), the biceps femoris and gluteus medius (top sirloin steak), and the semimembranosus and biceps femoris (round steak). ES, in addition to improving tenderness of the longissimus dorsi, increased tenderness of other major muscles in the carcass.

Effect of Comminution Method and Pressure on Restructured Beef Steaks

Restructured steaks were made using six methods of meat comminution: (a) sliced parallel, (b) sliced perpendicular to muscle fibers (2-mm thick slice), (c) flaked at −5 C, (d) flaked at −2.2 C, (e) flaked at 2.2 C and (f) ground through a 3.2-mm plate. Meat used was from cow inside rounds. After comminution, meat was stuffed into casings and pressed under pressure (200, 600 or 1,000 psi). The “logs” were then frozen, cut into steaks and evaluated for cooking characteristics and sensory attributes. Intact round steaks were used for controls. The amount of pressure used to form the restructured steaks had no effect (P>.05) on any of the cooking characteristics or sensory properties. Particle production method had no effect (P>.05) on cooking characteristics; however, tenderness, texture description and flavor desirability ratings were higher (P>.05) for flaked steaks as compared to the sliced or intact steaks.

DIFFERENCES AMONG TOP ROUND STEAKS COOKED BY DRY OR MOIST HEAT IN A CONVENTIONAL OR A MICROWAVE OVEN

ABSTRACTTop round steaks were cooked by dry or moist heat in conventional or microwave ovens with rotary hearths. Gardner color‐difference values and final temperature data demonstrated that a steak is heated more evenly by conventional, dry heat than by conventional moist or by microwave dry or moist heat. Cooking time, volatile cooking losses, total moisture, and sensory juiciness and tenderness scores were less (P < 0.001), whereas total and drip cooking losses (P < 0.001) and ether extract (P < 0.05) were more for steaks cooked by microwaves than for conventionally cooked steaks. Cooking time was greater (P < 0.001), but total and drip cooking losses were less (P < 0.001) for steaks cooked by dry heat than for those cooked by moist heat.

RETAIL APPEARANCE OF ELECTRICALLY STIMULATED BEEF

ABSTRACTTop round steaks (adductor) and ground beef from the top round were obtained from both sides of ten U.S. Choice carcasses. Left sides were electrically stimulated (ES) with 17 impulses (1.8 set duration, 1.8 set interval) of 550 volts of alternating current at 5 amps. Steaks and ground beef from top rounds from nonstimulated right sides served as control (CON) samples. Steaks and ground beef were displayed under simulated retail conditions for 4 and 3 days, respectively. Steaks were weighed prior to and at the termination of the display interval to determine percentage weight loss. Samples for microbiological evaluation were obtained prior to and at the termination of the display interval. No significant differences were observed for muscle color, surface discoloration or overall appearance for samples of ground beef at any retail display interval. With one exception, muscle color was brighter and surface discoloration was reduced for round steaks from ES sides. Few significant differences in overall appearance were observed between ES and CON samples during the display period. No significant differences between ES and CON samples were observed for bacterial counts either initially or at the termination of the display period for either steaks or ground beef samples. Percentage weight loss was not significantly different between ES and CON steaks. These data suggest that electrical stimulation may enhance, and certainly does not detract from, the appearance of round steaks displayed under retail market conditions.

CONSUMER ACCEPTABlLITY AND RETAIL YIELD IN BEEF AFTER PELVIC SUSPENSION AND DELAYED CHILLING

ABSTRACTThe effect of pelvic versus Achilles' tendon suspension, combined with reduced rate of beef carcass chilling during the first 24 hr postmortem, on tenderness and consumer acceptability of round and loin steaks and on retail yield from the hindquarter were determined in this study. Chilling temperature (‐2.2, 3.3 or 8.9°C) did not affect retail yield. Pelvic suspended hindquarters yielded less lean trim (P < 0.001) but had higher yields of round steak and rump roast. Total retail yield was not affected by method of carcass suspension. Pelvic suspension reduced the dimensions of round steaks and produced a more round shape in short loin steaks as compared to normal suspension. Loin steaks from pelvic suspended carcasses were rated more tender (P < 0.001) by a laboratory panel, had longer sarcomeres (P < 0.001) and slightly greater myofibril fragmentation; however, chilling temperature did not significantly affect these traits. 614 consumer evaluations of overall palatability in loin and round steaks were received. Consumers ranked steaks from pelvic suspended carcasses higher (P < 0.01) than those from normally suspended carcasses. Consumers who indicated they normally purchased Choice grade beef perceived less difference between suspension methods and ranked all steaks lower than consumers who normally purchased Good grade or “whatever was sold in the supermarket.” Chilling temperature did not affect consumer rankings of palatability. It is believed that the fat cover on the carcasses was sufficient to prevent muscle temperature from dropping to levels at which cold shortening occurs, even with the lowest chill temperatures used in this study.

Short‐Run Predictive Models for Retail Meat Sales

Demand analysis has long been a central concern of agricultural economists. Typically, price-quantity relationships have been examined using time-series data for various commodities for broad geographic areas. The results have proven useful for many types of decisions (Brandow, Breimyer), but they are of limited value at those stages in the food system where specific products are traded (round steak or ground beef rather than U.S. Choice beef carcasses), where the sales of an individual firm must be estimated rather than the sales of all firms in a market or region, and in those situations where firms operate in a short-term decision environment with short-run variations in demand that are not accounted for in traditional demand models. All of these conditions hold for individual retail food firms. Short-run variations in the demand faced by food retailers are particularly troublesome in accurately anticipating sales. Retailers operate in local markets with considerable interdependence with other retail food firms. The behavior of competitors is difficult to anticipate and thus may alter the demand faced by a particular firm from week to week. In addition, industry personnel contend that other factors also influence short-run demand and/or sales. These include weekly advertised specials, merchandising variables such as the closeness of trim or the size and location of displays, and closeness to payday. Variations in the farm and wholesale prices of commodities such as broilers, beef, and pork (as well as many other agricultural commodities) are often substantial from week to week or even within a single week. While variations in supply account for some of the variation in prices, industry participants have also contended that variations in demand-largely due to supermarket specialling activity--are also important causes of short-run price instability. The research summarized in this paper examines the weekly price-quantity relationships for specific meat products at the retail store level. It is thus concerned with short-run demand relationships that have a direct bearing on the pricing, ordering, and inventory control tasks of retail food firms, and that also influence the short-run derived demand sched-

Comparative performance of calves from Bunaji (White Fulani) dams and Gharolais, three-quarter Friesian and Bunaji sires

SUMMARYComparative evaluation was made on the live weight and growth pattern of calves from Bunaji (White Fulani) cows sired by Charolais, three-quarters Friesian crossbreds (three quarters Friesian and one quarter Bunaji) and Bunaji bulls in 2 years. Twelve steers per breed were evaluated on carcass merit after 250 days postweaning feeding.Results showed that the Charolais half-cross and the Friesian three-eighth calves were heavier by up to 7, 23, 57 and 51 kg respectively at birth, weaning, 112 and 250 days after weaning than the Bunaji calves. The carcass data indicated superior slaughter weight and loin eye area in favour of the cross - breds, but no differences were found for dressed weight, dressing percentage, carcass grade and hide weight percentage among the breed groups. Carcass retail cuts showed heavier sirloin steaks and round steaks in favour of the cross-breds also.The results were indicative of the superior growth of the cross-breds and underlined their carcass potential which may be useful in upgrading the indigenous stock. In view of the small numbers of progeny per sire group, especially among the cross-breds, further work needs to be done to confirm the present trend.

EFFECTS OF POST–COOKING SAMPLE TEMPERATURE ON SENSORY AND SHEAR ANALYSIS OF BEEF STEAKS

ABSTRACTThe effect of post‐cooking beef sample temperatures of 22°C (room temperature) and 50°C on sensory and shear analyses was determined. Oven roasted beef bottom round steak sample cores (1.88 cm) were halved, with one‐half being maintained at room temperature and the other at 50°C. A calibrated double boiler‐hot plate system was used to accurately control sample temperature. Six trained sensory panelists rated all samples on 7‐point rating scales for flavor, initial juiciness, sustained juiciness, initial tenderness and overall tenderness. Warner‐Bratzler shear determinations were also obtained. Samples held at 50°C had significantly higher flavor (P < 0.01), initial tenderness (P < 0.01) and overall tenderness (P < 0.02) values. Initial juiciness was significantly lower (P < 0.01) for the 50°C samples, while no significant differences in sustained juiciness were detected. Shear values were significantly lower (P < 0.01) for samples held at 50°C. Differences in sensory ratings due to post‐cooking sample temperature variation are greatest for initially perceived characteristics such as flavor, initial juiciness and initial tenderness.

RELATIONSHIP OF HYDROXYPROLINE SOLUBILIZED TO TENDERNESS OF BOVINE MUSCLE

ABSTRACTHydroxyproline assay and sensory evaluation were used to study tenderizing effects of two oven temperatures (94°, 149° C) and two end‐point temperatures (70°, 80°C) on top round steaks cooked in oven film bags. Hydroxyproline solubilized during cooking ranged from 1.47‐1.80%, and did not differ significantly between oven temperatures or between end‐point temperatures. Sensory tenderness scores were higher (P 0.01) for steaks cooked to 70° than for steaks cooked to 80° C. With cooking at 94‐80°C hydroxyproline solubilized was related to tenderness score (r = 0.77*) and shear value (r = 0.61). Time the internal temperature of steaks remained between 55° and 60°C was related to hydroxyproline solubilized (r = 0.70), tenderness score (0.86**), and softness score (0.73*).

EFFECT OF PACKAGING METHODS ON THE DEVELOPMENT OF YERSINIA ENTEROCOLITICA ON BEEF STEAKS

Top and bottom round steaks inoculated with Yersinia enterocolitica were stored vacuum packaged and in polyvinyl chloride (PVC) films at 1, 2.5 and 5°C for 21–35 days. Y. enterocolitica and total aerobic plate counts of steaks were consistently higher in the more oxygen permeable film (PVC) than in the vacuum packages. The microbial flora of the vacuum packaged steaks at the end of the storage period (21–35 days) consisted, in addition to Y. enterocolitica, primarily of Lactobacillus spp., that of the steaks stored in PVC of Pseudomonas spp.

PALATABILITY AND COOKING CHARACTERISTICS OF MECHANICALLY TENDERIZED BEEF

This paper reports observations on the palatability and cooking properties of mechanically tenderized (“needled”) U.S. Good grade beef cuts. Top round roasts, chuck top blade boneless roasts, top round steaks and top loin boneless steaks were evaluated. Highly significant improvements in tenderness, measured by Warner-Bratzler shear, were found in round roasts and in round and loin steaks due to mechanical tenderization. Initial and residual sensory tenderness evaluations showed a decided tenderization effect of the treatment on round steaks only. The tenderization process reduced cooking time and juiciness of round roasts and increased drip cooking losses from both types of roasts, but did not affect any of these properties of steaks. Mechanical tenderization had no influence on any of the other observed properties of beef (total and evaporation cooking losses, cooked muscle fluid content and desirability of flavor). Tests for interactions showed that the method of cooking roasts (dry heat or moist heat) did not influence the tenderness and other observed properties of mechanically tenderized beef. Similarly, except for total moisture of round steaks, mechanical tenderization of beef cuts did not alter the effects induced by a meat temperature of 80°C compared to 70°C.

Method for the Determination of Aflatoxin in Animal Tissue

Abstract The method consists of methanol extraction, purification of the extract by transfer from aqueous methanol to chloroform, silica gel column chromatography, partition chromatography according to Pons on a celluloseaqueous methanol column, and quantitation by TLC fluorodensitometry. Average recoveries of B1, B2, G1, G2, and M1 from liver, kidney, heart, and round steak spiked at 0.05, 0.1, and 0.2 μg/kg were 43–123% as measured by TLC fluorodensitometry. The method was successfully applied to the analysis of naturally contaminated liver, kidney, and heart tissues.

WEIGHT AND COLOR CHANGES DURING STORAGE OF BEEF STEAKS PACKAGED IN CLEAR PLASTIC, FOAM AND PULP TRAYS

SUMMARY4 trials were conducted using 144 U.S. Choice‐grade beef round steaks packaged in pulp, foam and clear plastic trays overwrapped with PVC film. Percent weight losses, at the end of 2 and 4 days of storage, were significantly greater for those steaks packaged in pulp trays as compared to clear or foam trays (P<.01). Evaporation losses from the various types of trays employed in this study were relatively uniform and differences in steak weight losses were primarily accounted for by absorbed or free juices in the tray. The color acceptability of all steaks declined during storage and there was no particular color advantage associated with any tray type. Visibility of steak undersides through clear plastic trays remained at an acceptable level throughout the storage period. A stacking effect was observed as top packages of stacks lost more weight and showed greater color discoloration than bottom packages.

Sensory Differentiation of Beef Tenderness and Juiciness Components Over Short Intervals of Cooking Time

SUMMARY: The ability of judges to distinguish differences in juiciness and six components of tenderness of top round steaks cooked at 350°F for 20, 23, 26, and 29 min was studied by use of a paired comparison design. Concurrently, the effects of cooking time on cooking losses, percents moisture, nitrogen, and fat, shear values, “loose water” and “immobilized water” were evaluated. Judges detected differences for all factors between steaks cooked 20 and 26 min, but were unable to detect differences between steaks cooked 26 and 29 min. Differences between steaks cooked 20 and 29 min were found for all factors except fragmentation and adhesion.

Residue Deposition of Co-Ral in the Tissues of Back-Line-Treated Cattle1

The pour-on method was used to administer 7.5 g. of Co-Ral® (O,O-diethyl O-3-chloro-4-methyl-2-oxo-2H-1-benzopyran-7-yl phosphorothioate) in 375 ml. of white mineral oil to the backs of 4 steers. Four steers received 5 g. of Co-Hal in 250 ml. of oil, and 4 control steers were treated with plain oil. At intervals of 7, 14, 28, and 42 days after treatment, a steer was slaughtered from each group. Ten different samples of tissues or organs were removed from each animal and analyzed for Co-Ral residues. The greatest amounts of Co-Ral in the tissues were found 7 days after treatment, and no residues in excess of 0.07 p.p.m. were found. No Co-Ral residues were detected in any of the following tissues or organs after the 7-day sampling period: liver, kidney, heart, and renal fat. Small amounts of Co-Ral were found in the other samples at various intervals after treatment. There was no evidence of “off” flavor in the loin steaks (longissimus dorsi) or round steaks (semimembranosus) taken from the cattle that were slaughtered 7 days after treatment.