title: The impact of ultimate pH on muscle characteristics and sensory attributes of the longissimus thoracis within the dark cutting (Canada B4) beef carcass grade.
abstract: Canada B4 beef carcasses are penalized because the longissimus thoracis (LT) at the grade site (12-13th ribs) is darker than the color threshold for normal bright cherry-red beef. Previous studies have shown that not all B4 carcasses have pH>6.0; therefore, the relationship between LT pH and meat quality was investigated by collecting thirty half-carcasses comprised of the following: ten Canada AA (AA, control), ten B4 with LT pH>6.0 (CL, classic), and ten B4 with LT pH<6.0 (AT, atypical). LT from CL carcasses had the lowest mean lactate level, lowest glucidic potential and highest mean pH value. LT muscle from CL and AT carcasses was dark and had decreased purge, drip loss and cooking loss. Warner-Bratzler shear force values and sensory panel results showed that AT beef was toughest (P<0.0001), substantiating economic penalty. Causal mechanisms for AT carcasses may be inconsistent with traditional DFD theory because of close to normal final muscle pH.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, 4-10 Agriculture/Forestry, University of Alberta, Edmonton, Alberta T6G 2P5, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Holdstock
authors.affiliation: Agriculture and Agri-Food Canada, 6000 C&E Trail, Lacombe, Alberta T4L 1W1, Canada.
authors.forename: J L
authors.initials: JL
authors.lastname: Aalhus
authors.affiliation: Agriculture and Agri-Food Canada, 6000 C&E Trail, Lacombe, Alberta T4L 1W1, Canada.
authors.forename: B A
authors.initials: BA
authors.lastname: Uttaro
authors.affiliation: Agriculture and Agri-Food Canada, 6000 C&E Trail, Lacombe, Alberta T4L 1W1, Canada.
authors.forename: O
authors.initials: O
authors.lastname: López-Campos
authors.affiliation: Agriculture and Agri-Food Canada, 6000 C&E Trail, Lacombe, Alberta T4L 1W1, Canada.
authors.forename: I L
authors.initials: IL
authors.lastname: Larsen
authors.affiliation: Department of Agricultural, Food and Nutritional Science, 4-10 Agriculture/Forestry, University of Alberta, Edmonton, Alberta T6G 2P5, Canada. Electronic address: hbruce@ualberta.ca.
authors.forename: H L
authors.initials: HL
authors.lastname: Bruce
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002170:Canada; D002417:Cattle; D003116:Color; D003296:Cooking; D004587:Electrophoresis, Agar Gel; D005260:Female; D005511:Food Handling / Q000379:methods; D063427:Food Quality; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008460:Meat / Q000032:analysis* / Q000592:standards / Q000706:statistics & numerical data*; D018482:Muscle, Skeletal / Q000737:chemistry*; D010858:Pigmentation; D016133:Polymerase Chain Reaction; D013649:Taste
keywords: Beef quality; Dark, firm and dry (DFD) beef; Sensory; Ultimate pH