Round Steaks Research Articles

Lean color characteristics of bullock and steer beef.

Twelve young bulls and 12 steers were slaughtered and the carcasses were fabricated at 48 h postmortem. Top rounds, bottom rounds, and rib eyes were vacuum-packaged and stored at 0 degrees C until 21 d postmortem. After subprimal storage, steaks were removed from each cut and displayed under simulated retail conditions for 3 d. Consumer panelists (n = 110) showed little difference in buying preference for top round, bottom round, and rib eye steaks from steers vs bullocks. Also, consumer panelists could not detect color differences between steaks from steers and bullocks. Experienced panelists (n = 6) detected brighter (P less than .05) muscle color for top round and rib eye steaks from steers but detected no difference in muscle color of bottom round steaks from bullocks and steers. Generally, overall desirability scores favored steaks from steer carcasses. This was particularly true of rib eye steaks. Sex-class of carcass did not affect aerobic plate counts of top round, bottom round, or rib eye steaks either before or after 3 d of retail display. Muscle pH was lower for top round and rib eye steaks from steer carcasses; however, the magnitude of this difference was not large enough to affect retail display stability. Muscle pH of bottom round steaks was not affected by sex-class. Although experienced panelists could detect differences in visual appearance of beef retail cuts from steers and bullocks, consumer panelists did not show a clear purchase preference for steer vs bullock beef. These data suggest that beef retail cuts from bullocks are acceptable in visual appearance.

Effect of an Edible Collagen Film Overwrap on Exudation and Lipid Oxidation in Beef Round Steak

ABSTRACTBeef round steak when wrapped with an edible collagen film (Coffi®) exhibited much less fluid exudate (P<0.05) than unwrapped controls. This was true in refrigerated and frozen/thawed samples with standard retail (permeable film overwrap) or vacuum (pouch) packaging. Vacuum packaging produced more exudate and a less bright red color than retail packaging. Coffi® had no significant effect on color or lipid oxidation by TBA. Objective measures of color and exudate quantity highly correlated with panel scores for the same parameters (r values of 0.91 and 0.95). TBA values were lower (P<0.05) in refrigerated vacuum‐packaged than in retail‐wrapped samples. The impact of vacuum on TBA was less apparent in frozen samples.

Nutrient composition of raw and cooked Bison bison

Longissimus muscle from 30 bison were lyophilized and analyzed for various nutrients including moisture, protein, fat, cholesterol, gross energy, minerals, and fatty acids. In addition nine shoulder roasts and three round steaks were also collected. The relative amounts of nutrients to total calories make bison a highly nutrient-dense food, similar to domesticated meats such as beef, pork, and chicken. The lean tissue was low in fat (<2%) and contained 138 kcal/ 100 g on a raw weight basis. Cholesterol values were similar to those of other meats. Bison longissimus muscle apparently had higher concentrations of phosphorous, calcium, iron, and magnesium but lower concentrations of potassium, copper, manganese, and zinc than beef. No differences among the meats tested were observed for sodium. Relative percentages of saturated and monounsaturated fatty acids were similar for bison and beef however, the concentrations of the individual fatty acids varied. Bison contained greater amounts of stearic and linolenic acid but less palmitic and myristic acid than beef.

Effect of Warmed‐Over Flavor on Consumer Acceptance and Purchase of Precooked Top Round Steaks

ABSTRACTRetail samples of semimembranosus were roasted, sliced, wrapped in aluminum foil and stored at 1.0°C for 0, 1, 4, and 7 days. A panel of 100 consumers evaluated samples for the variables: preference, purchase intention, flavor, off‐flavor, and intended purchase frequency at three price levels. Panelists did not rate the 0, 1, and 4‐day samples differently on all sensory variables, but the 7‐day sample was rated as significantly different (P &lt; 0.05) from all samples on each sensory variable. Results indicate that consumers were unable to detect off‐flavor in reheated semimembranosus samples at TBA numbers of 6.3 or lower.

RELATIONSHIP OF USDA QUALITY GRADES TO PALATABILITY OF COOKED BEEF1

ABSTRACTPrime carcasses produced loin and round steaks that were more palatable (P &lt; 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.

Lipid Characteristics in Fresh and Broiled Loin and Round Steaks from Concentrate Fed and Pasture Grazed Steers

ABSTRACTBroiling of loin and round steaks from concentrate‐fed and pasture‐grazed steers had no significant effects upon levels of intramuscular triglycerides or cholesterol when expressed on a freeze‐dry basis. Broiling did cause increases in phospholipids and free fatty acids. Broiling did not influence fatty acid compositions of triglycerides, polar lipids and free fatty acids. Loin steaks contained more triglycerides and free fatty acids and less phospholipids and cholesterol than round steaks. Increases in intramuscular triglycerides were not accompanied by increases in cholesterol or phospholipids. Polyunsaturated/ saturated acid ratios and levels of linolenic acid, an n‐3 acid, were highest in steaks from steers that had grazed pastures.

Ultraviolet Radiation—An Effective Bactericide for Fresh Meat

Ultraviolet radiation (UV), with principal energy at a wavelength of 253.7 nm, was effective in destroying bacteria on the surface of fresh meat. A radiation dose of 150 mW s/cm2 (275 uW/cm2 for 550 s) reduced bacteria on smooth surface meat (beef plate) about 2 log cycles (99% “kill”). Further increases in dose level to 500 mW s/cm2 (275 uW/cm2 for 1800 s) reduced the bacteria level one additional log cycle. Since UV radiation does not penetrate most opaque materials, it was less effective on rough surface cuts of meat such as round steak because bacteria were partly shielded from the radiation. Unlike gamma (ionizing) radiation, UV had no deleterious effects on color (Hunter “a”, redness) or general appearance. UV treatment chambers could be easily installed in new or existing meat processing facilities at relatively low cost. Experimental results indicate that UV irradiation of meat carcasses could effectively increase the lag phase of bacteria multiplication until adequate cooling had occurred.

Reference materials for agricultural and food analysis: Preparation and physical characterization of a bovine muscle powder candidate reference material

The most cost-effective way of monitoring and maintaining reliability of an analytical procedure is by the incorporation of appropriate, compositionally-similar reference materials into the scheme of analysis. Agricultural and food commodities represent an extremely wide range of composition in respect of both the sought-for analyte and the remainder of the supporting material (matrix) which are not reflected in currently-available biological reference materials (BRMs). In an attempt to fill some of these gaps in the world repertoire of reference materials, cooperative work is underway to prepare and characterize a number of materials for data quality control for inorganic constituents. The first two products of this venture, Maize Stalk and Maize Kernel Reference Materials 8412 and 8413, respectively, with recommended concentrations for eleven elements are available from USNBS. A third product, a powdered Bovine Muscle candidate reference material has been prepared in quantity. Meat from beef cattle (Bos Taurus) comprising muscles commonly-denoted round steak was trimmed, ground, freeze-dried, γ-ray sterilized, ball milled, sieved, blended and packaged. The final product was a finely powdered, visually uniform material consisting of muscle fibers with over 70% of the particles with radius of an equivalent sphere in the range 10–40 μm (median 25 μm).

Feedlot performance and carcass evaluation of heifers fed finishing diets as weanling calves or as yearlings

Twenty commercial Herefored, Angus and Hereford × Angus, weanling and yearling heifers from the same herd were compared for feedlot performance and certain carcass characteristics. Yearlings tended to gain weight more rapidly than did weanlings. Since the cattle were group-fed, no analyses of feed efficiency could be performed. Yearlings appeared, however, to require less feed per unit of gain. The cattle were slaughtered when live weight approached 443 kg. Weanlings were fatter; had more kidney, pelvic and heart fat; merited higher (less desirable) USDA yield grades; had more desirable USDA quality grades and higher dressing percentage ( P<0·05) than did yearlings. Ribeye area was not different between treatments. Yearlings yielded a higher percentage of closely trimmed retail lean cuts than did weanlings ( P < 0·05). Sensory panel scores were higher (more desirable) for weanlings than for yearlings for both ribeye and inside round steaks ( P < 0·05), while no differences were identified for flavor, juiciness or overall palatability of steaks. Warner-Bratzler shear force data generally supported taste panel evaluations for tenderness. These data suggest that carcass composition is impacted by the way cattle are managed and refute the idea that cattle have the same body composition at a given weight regardless of age at slaughter or nutrient density of the diet during finishing.

Effects of Slaughter Weight and Carcass Electrical Stimulation on the Quality and Palatability of Beef from Young Purebred Bulls

Seventy-eight purebred Angus and Brahman bulls (10 to 18 mo at slaughter) were used to determine the effects of slaughter weight (60, 80, 90 or 100% of the average mature-cow weight for the respective breed) and carcass electrical stimulation (500 V, 20 2-s impulses on the right side) on carcass and meat characteristics. Angus bulls grazed summer forage (millet) after weaning, while Brahman bulls were fed to stimulate gains achieved on forage by Angus bulls. Bulls were then placed in the feedlot for finishing to their designated slaughter weight (293, 381, 412 and 463 kg for Angus and 316, 420, 463 and 516 kg for Brahman). Coarse dark band formation and lean color problems normally associated with bullock carcasses were either eliminated or reduced by stimulation. Increasing slaughter weight from 60 to 90% was associated with an increase in panel tenderness scores for loin steaks. However, increasing slaughter weight from 90 to 100% little change was detected. On the other hand, shear values for loin steaks decreased with increasing slaughter weight. Stimulation increased the tenderness of loin steaks as determined by both panel scores and shear values, and of bottom round steaks (shear-force values). The data from this study suggest that meat from the bulls slaughtered at lighter weights was generally tough, but was improved when bulls were fed to heavier, yet acceptable weights. This research encourages implementation of electrical stimulation on carcasses from young bulls to improve quality-indicating factors.

Mutagen formation in a model beef supernatant fraction. IV. Properties of the system.

To identify the precursors and elucidate the reaction conditions that yield heterocyclic amine mutagens in cooked meat products and fish, we have used a supernatant 2 (S2) fraction prepared from H2O-homogenized lean round steak. Compounds (MW less than 500) in S2 are the sources of the microsomal-dependent, Salmonella TA 1538 mutagenic activity in open boiled (aqueous), 200 degrees C pressure-heated (aqueous), or 200 to 300 degrees C oven-baked (freeze-dried) homogenates. Combined incorporation-HPLC experiments show that they are also the precursors for frameshift mutagen formation in the outer surfaces of 200 degrees C griddle-fried ground beef. Maximal stimulations of boiled S2 mutagenic activity are given by 10 mM Trp, 2.5 mM creatine phosphate (CP), and synergistically by 10 mM Trp + 2.5 mM CP + 1.0 mM FeSO4 (a mixture abbreviated as S2*). Boiling S2 for 30 hr at the acidic optimum pH of 4.0----600 TA 1538 revertants (no additions) and 1,400 revertants (+CP), while S2*----24,000 revertants/10(8) bacteria/g of dry beef. By the criteria of HPLC, paper electrophoresis, and resistance of the active HPLC fractions to acid-nitrite inactivation, boiled S2 contains 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) and a minor amount of 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ). Boiling S2 with CP doubles the IQ, halves the Trp-P-2, produced traces of MeIQ, and generates an unknown nitrite-resistant mutagen. Boiled S2* contains these same four mutagens, but both the IQ and Trp-P-2 are increased and large amounts of Trp-P-1 also are generated. The identities of IQ, Trp-P-2, and Trp-P-1 were verified by purification and by light-absorption and mass spectra. Their increments in stimulated S2 indicate that Trp (or its degradation products) and CP (or its degradation products) are the beef juice precursors for the indole ring in Trp-P type mutagens and the NH2-imidazole ring in IQ-type mutagens, respectively. Aqueous (pressure) heating or oven-baking S2 for 2 hr at 200 degrees C greatly elevates its TA 1538 activity----45,000 revertants/10(8) bacteria/g of dry beef; dry heating at 300 degrees C----approximately 180,000 revertants/g of dry beef. Along with the increases in total TA 1538 activity at 200 to 300 degrees C, the number of mutagens formed from the less than 500 MW S2 precursors also multiplies.(ABSTRACT TRUNCATED AT 400 WORDS)

Mutagen Formation in a Model Beef Supernatant Fraction. IV. Properties of the System

To identify the precursors and elucidate the reaction conditions that yield heterocyclic amine mutagens in cooked meat products and fish, we have used a supernatant 2 (S2) fraction prepared from H2O-homogenized lean round steak. Compounds (MW less than 500) in S2 are the sources of the microsomal-dependent, Salmonella TA 1538 mutagenic activity in open boiled (aqueous), 200 degrees C pressure-heated (aqueous), or 200 to 300 degrees C oven-baked (freeze-dried) homogenates. Combined incorporation-HPLC experiments show that they are also the precursors for frameshift mutagen formation in the outer surfaces of 200 degrees C griddle-fried ground beef. Maximal stimulations of boiled S2 mutagenic activity are given by 10 mM Trp, 2.5 mM creatine phosphate (CP), and synergistically by 10 mM Trp + 2.5 mM CP + 1.0 mM FeSO4 (a mixture abbreviated as S2*). Boiling S2 for 30 hr at the acidic optimum pH of 4.0----600 TA 1538 revertants (no additions) and 1,400 revertants (+CP), while S2*----24,000 revertants/10(8) bacteria/g of dry beef. By the criteria of HPLC, paper electrophoresis, and resistance of the active HPLC fractions to acid-nitrite inactivation, boiled S2 contains 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) and a minor amount of 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ). Boiling S2 with CP doubles the IQ, halves the Trp-P-2, produced traces of MeIQ, and generates an unknown nitrite-resistant mutagen. Boiled S2* contains these same four mutagens, but both the IQ and Trp-P-2 are increased and large amounts of Trp-P-1 also are generated. The identities of IQ, Trp-P-2, and Trp-P-1 were verified by purification and by light-absorption and mass spectra. Their increments in stimulated S2 indicate that Trp (or its degradation products) and CP (or its degradation products) are the beef juice precursors for the indole ring in Trp-P type mutagens and the NH2-imidazole ring in IQ-type mutagens, respectively. Aqueous (pressure) heating or oven-baking S2 for 2 hr at 200 degrees C greatly elevates its TA 1538 activity----45,000 revertants/10(8) bacteria/g of dry beef; dry heating at 300 degrees C----approximately 180,000 revertants/g of dry beef. Along with the increases in total TA 1538 activity at 200 to 300 degrees C, the number of mutagens formed from the less than 500 MW S2 precursors also multiplies.(ABSTRACT TRUNCATED AT 400 WORDS)

RELATIONSHIP OF USDA MARBLING GROUPS TO PALATABILITY OF COOKED BEEF

AbstractAs marbling increased from“practically devoid” to“moderately abundant”, loin steaks were more palatable (P&lt;0.05) about 2/3 of the time, round steaks were more palatable (P&lt;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.

Mutagen formation in a model beef boiling system III. purification and identification of three heterocyclic amine mutagens‐carcinogens

Abstract An extensively boiled supernatant2 (S2) fraction from beef round steak contains two major Salmonella frameshift mutagens, designated as HPLC peaks A and B. These same mutagens arise, but in different proportions, when S2 is boiled with creatine phosphate (CP), and they are produced in much greater quantities from a boiled mixture of S2 + L‐tryptophan (Trp) + CP + FeSO4 (S2 ∗). A third mutagen, peak C, is also generated in the S2 ∗ mixture. Mutagen peaks A, B, and C were purified to homogeneity and shown by their absorption spectra, mass fragmentation patterns, and other data to be 2‐amino‐3‐methylimidazo[4,5‐f]quinoline (IQ), 3‐amino‐l‐methyl‐5H‐pyrido[4,3‐b]‐indole (Trp‐P‐2), and 3‐amino‐l,4‐dimethyl‐5H‐pyrido[4,3‐b]indole (Trp‐P‐1), respectively. This is the first demonstration that IQ, Trp‐P‐2, and Trp‐P‐1 can form under aqueous conditions at 100°C from reactions between low molecular wt precursors that are present in meat juice. Further simplification of and studies with the S2 fraction of be...

Beef Jerky: Fate of Staphylococcus aureus in Marinated and Corned Beef during Jerky Manufacture and 2.5°C Storage

A domestic food dehydrator was used to prepare beef jerky from inside round steak and corned beef brisket slices contaminated with Staphylococcus aureus. The number of added staphylococci doubled within 2 h after the start of drying corned beef slices. About 3–3.5 h were required for corned beef and between 1–2.5 h for inside round slices to reach an aw of 0.86. Only 15% of all staphylococci initially present survived 8 h of heated-drying, and this was reduced to 5% after a week of refrigerated storage of slices. The safety of beef jerky produced in the home is assured when wholesome meats used in its preparation are rapidly dried.

Comparison of Top Round Steaks Cooked by Microwave-Convection, Forced-Air Convection and Conventional Ovens

AbstractThis study compared microwave-convection, forced-air convection and conventional electric ovens as to time and energy requirements, uniformity of cooking, and effect on cooking losses, sensory characteristics, moisture, fat, thiamin and riboflavin content of top round beef steaks. Sensory evaluation indicated no significant difference in juiciness; tenderness, including number of chews; intensity of beef flavor; and external color of the steaks cooked by the three ovens. Also, moisture, fat, thiamin and riboflavin content of the meat did not differ among treatments. Total cooking losses and percentage evaporation were greater (P<0.05) for steaks cooked in the microwave-convection oven than for those cooked by the other two methods. Drip losses were greater (P<0.05) with the microwave-convection than with the forced-air convection method of cooking top round beef steaks. The least total cooking time was required for the microwave-convection oven and the most for the forced-air convection oven. On a...

Consumer Acceptance of Steaks and Roasts from Charolais Crossbred Bulls and Steers

ABSTRACTForty‐eight Charolais bulls (n=24) and steers (n=24) were commercially fed, slaughtered and subprimals were distributed to three retail stores. Consumers were able to detect differences in tenderness for steaks from the rib, loin and top sirloin of bulls and steers, but not for steaks or roasts from the round (except for the eye of round steak) and chuck of bulls and steers. However, 91.7% and 86.8% of the consumers of steaks from steers and bulls, respectively, indicated that they would purchase similar steaks again while 92.3% and 93.2% of the consumers of roasts indicated they would purchase similar roasts from steers and bulls, respectively.

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.

Mutagen formation in a model beef boiling system I. Conditions with a soluble beef‐derived fraction

Abstract Fried beef and commercial beef extract contain Ames/ Salmonella frameshift mutagens that require microsomal (S‐9) activation. To ascertain which fraction(s) of beef muscle contain(s) the essential precursors, aqueous (1:1) homogenates of lean round steak were centrifuged to give an insoluble residue1 (R1) and a soluble supernatant1 (S1). S1 was then boiled for 30 min and again centrifuged, yielding a residue2 (R2) and a soluble supernatant2 (S2). S2 represents only 5% of the meat dry wt and it contains only 10∗ of the H2O‐soluble protein, but it contributes all of the S‐9 dependent Salmonella TA1538 mutagenic activity in boiled homogenates. Mutagen formation from S2 boiled for 0–30 h at a constant volume increases exponentially with time and displays sharp pH optima at 4.0 and 9.0. By molecular ultrafiltration the pH 4.0 mutagen precursors in S2 have molecular wts < 500. They are also stable to lyophilization. These observations and the disappearance of certain amino acids upon boiling at pH 4.0 ...

Mutagen formation in a model beef boiling system II. Effects of proteolysis and comparison of soluble fractions from several protein sources

Abstract Fried beef and commercial beef extracts contain Ames/Salmonella frameshift mutagens that form at relatively low temperatures (100–200°C). To investigate the types of natural components in beef muscle that give rise to frameshift mutagenic activity, we previously devised a model boiling system and demonstrated that all of the Salmonella TA1538 activity is formed from H2O‐soluble, < 500 molecular wt compounds that are present in round steak supernatant fractions (S1 and S2). S2 is derived from S1, the soluble fraction of homogenized beef, by a brief 30 min boil and centrifugation. We now report that proteolysis of beef S1 with papain, trypsin, or chymotrypsin (± carboxypeptidase A) increases the mutagenic activity of boiled S2 by 1.8–4.5 fold over the baseline range of 90–100 TA1538 revertants/108 bacteria/g dry beef/14 h at pH 4.0. Sequential treatment of beef S1 with chymotrypsin followed by carboxypeptidase A is the most efficient mutagen enhancing digestion (415 revertants/g dry beef or 7.7 rev...