title: Effects of biological type and dietary fat treatment on factors associated with tenderness: II. Measurements on beef semitendinosus muscle.
abstract: The objective of this study was to evaluate attributes in semitendinosus muscle (ST) associated with tenderness in divergent breeds--Wagyu (W; n = 12), Limousin (L; n = 12), and Wagyu x Limousin cross cattle (WxL; n = 12)--fed two dietary treatments (0 or 6% sunflower oil, DM basis). A randomized complete block repeated measures design with a 3 x 2 factorial arrangement of treatments was used to measure effects of breed, diet, block, and associated interactions. Cattle were fed barley-based diets for an average of 259 d. Temperature and pH were measured at 0, 1, 3, 6, 12, and 24 h postmortem (PM). Steaks from the ST were removed 24 h postmortem, vacuum-packaged, aged (1, 3, 7, 14, 28, and 56 d postmortem) at 2 degrees C, and frozen (-40 degrees C) until analyzed. Dietary treatment did not (P > 0.10) affect Warner-Bratzler shear force (WBSF), collagen amount (OH-PRO) or cross-linking (HP), temperature, or pH. Steaks from WxL aged 14 d postmortem had lower (P < 0.05) WBSF values than L (W were intermediate). Cooking time was longer (P < 0.01) in W and WxL than in L; however, breed did not affect (P > 0.10) cooking loss. Cooking time was not influenced by diet, but steaks from cattle fed 6% sunflower oil had lower (P < 0.05) cooking losses. Temperature decreased more (P < 0.05) rapidly, and pH more slowly (P < 0.05), in W and WxL than L in the first 24 h postmortem. Limousin steaks were lighter (higher L*) and more yellow (higher b*) in color than steaks from W and WxL (P < 0.05). The control diet (no oil added) resulted in steaks that were lighter (P < 0.05) than the treatment diet (6% added sunflower oil). Neither breed nor diet affected (P > 0.10) OH-PRO or HP concentration. The results of this study indicate that biological type differences may not be as great in the ST as in longissimus muscle; thus, to increase tenderness in ST, emphasis may need to be placed on processing and cooking techniques rather than genetic selection.
authors.affiliation: Washington State University, Pullman 99163-6310, USA.
authors.forename: P S
authors.initials: PS
authors.lastname: Kuber
authors.forename: J R
authors.initials: JR
authors.lastname: Busboom
authors.forename: S K
authors.initials: SK
authors.lastname: Duckett
authors.forename: P S
authors.initials: PS
authors.lastname: Mir
authors.forename: Z
authors.initials: Z
authors.lastname: Mir
authors.forename: R J
authors.initials: RJ
authors.lastname: McCormick
authors.forename: C T
authors.initials: CT
authors.lastname: Gaskins
authors.forename: J D
authors.initials: JD
authors.lastname: Cronrath
authors.forename: D J
authors.initials: DJ
authors.lastname: Marks
authors.forename: J J
authors.initials: JJ
authors.lastname: Reeves
mesh_terms: D000818:Animals; D002417:Cattle / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D003094:Collagen / Q000378:metabolism; D003258:Consumer Behavior; D003433:Crosses, Genetic; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage* / Q000378:metabolism; D005511:Food Handling / Q000379:methods; D005524:Food Technology; D006863:Hydrogen-Ion Concentration; D008297:Male; D008460:Meat / Q000592:standards*; D018482:Muscle, Skeletal / Q000378:metabolism*; D010858:Pigmentation; D010938:Plant Oils / Q000008:administration & dosage* / Q000378:metabolism; D011897:Random Allocation; D000074242:Sunflower Oil; D013649:Taste; D013696:Temperature
chemical_list: D004042:Dietary Fats, Unsaturated; D010938:Plant Oils; D000074242:Sunflower Oil; D003094:Collagen