title: Variations in metabolite contents and protein denaturation of the longissimus dorsi muscle in various porcine quality classifications and metabolic rates.
abstract: The purpose of the present study was to investigate the variations in metabolite contents and muscle protein denaturation in various porcine quality classifications and metabolic rates. A total of 226 crossbred pigs were evaluated. Samples were classified based on muscle pH(45min) and R-value into fast or normal glycolysing group. Drip loss and lightness (L*) were used to assign samples as PSE, RSE, or RFN pork. Normal-glycolysing PSE pork contained an exceptional amount of initial glycogen and the high level of lactate at 24h postmortem (PM). The initial levels of metabolites related closely with muscle pH, R-value and protein solubility at 45min PM. The fast glycolysing group exhibited severe protein denaturation during the early postmortem period, and among them, fast-glycolysing PSE pork exhibited most pronounced protein denaturation. Via examination of each sarcoplasmic protein fraction, it was found that the bands for fructose-6-phosphate kinase, creatine kinase, triosephosphate isomerase, and myokinase were generally more evident as fainter bands in the fast-glycolysing pigs.
authors: Division of Food Science, College of Life and Environmental Sciences, Korea University, 5-1 Anam-dong, Sungbuk-gu, Seoul 136-701, South Korea.
authors: Y C
authors: YC
authors: Ryu
authors: Y M
authors: YM
authors: Choi
authors: B C
authors: BC
authors: Kim