title: Evaluating the point of separation, during carcass fabrication, between the beef wholesale rib and the beef wholesale chuck.
abstract: This study determined whether there is a logical point of value change, related to either tenderness or consumer acceptance, at which to separate the beef carcass within the rib/chuck region. Rib/chuck rolls (RCR); (n = 30) consisting of the ribeye roll and chuck eye roll subprimals (2nd through 12th rib locations) were cut into 22 steaks each (two steaks per rib location), and Warner-Bratzler shear force and consumer purchase preference were evaluated for steaks at each rib location. Steaks from different locations of the RCR were composed of differing proportions of several muscles: longissimus muscle (LM), spinalis dorsi and multifidus dorsi (SM), and complexus (CO). The LM (4th to 12th rib) contained three tenderness regions: 7th through 12th rib, 5th and 6th ribs, and 4th rib regions (lowest, intermediate, and highest shear force values, respectively; P < 0.01). Shear force differed (P < 0.05) among rib locations for the SM (2nd to 9th rib), but no logical pattern was evident. The CO (2nd to 7th rib) was more tender toward the anterior end (P < 0.05). The region of the RCR represented by the 4th through 6th rib locations had steaks with higher weighted-average shear force (average shear force of each steak, weighted for surface area of each muscle) values than the remainder of the RCR (P < 0.05). Animal-to-animal variation in shear force was 36% greater than rib-to-rib variation in shear force; thus, statistically significant differences in tenderness among rib locations may be undetectable by consumers. Steaks (n = 330) were offered for sale at a retail supermarket and case time was monitored on each steak to determine consumer purchase preference. Steaks from the 2nd through 4th rib locations required more time to sell (P < 0.01) than steaks from the 5th through 12th rib locations. Two alternative locations for the rib/chuck separation point could be between the 6th and 7th ribs, yielding a ribeye subprimal useful in marketing a "premium quality" product, or between the 4th and 5th ribs, which would yield four more 2.5-cm ribeye steaks per carcass.
authors.affiliation: Department of Animal & Range Sciences, South Dakota State University, Brookings 57007, USA.
authors.forename: B J
authors.initials: BJ
authors.lastname: Reuter
authors.forename: D M
authors.initials: DM
authors.lastname: Wulf
authors.forename: B C
authors.initials: BC
authors.lastname: Shanks
authors.forename: R J
authors.initials: RJ
authors.lastname: Maddock
mesh_terms: D000818:Animals; D001823:Body Composition / Q000502:physiology; D002417:Cattle; D003258:Consumer Behavior; D005511:Food Handling / Q000379:methods*; D019649:Food Industry; D008297:Male; D008460:Meat / Q000191:economics / Q000592:standards*; D018482:Muscle, Skeletal / Q000502:physiology