The significance of cooling rate on water dynamics in porcine muscle from heterozygote carriers and non-carriers of the halothane gene - a low-field NMR relaxation study

The post mortem changes in the chemical/physical state distribution of water were followed in pig muscle (AT longissimus dorsi) from heterozygote (n = 12) and non-carriers (n = 12) of the halothane gene exposed to two different cooling profiles using continuous low-field NMR relaxation measurements. T-2 relaxation data were analyzed using distributed exponential fitting analysis. Independent of genotype post mortem changes were observed in the two water populations characterizing water within the myofibrillar space (T-21) and the extra-myofibrillar space (T-22), respectively, as a function of chilling regime. The effect was most pronounced in samples from heterozygote carriers of the halothane gene. The obtained results strongly suggest that improved water-holding capacity of muscles upon fast chilling can be ascribed to a reduced accumulation of extra-myofibrillar water in the meat post mortem, and it is hypothesized that differences in the accumulation of extra-myofibrillar water post mortem can be ascribed largely to the time at which disruption of cell membrane integrity takes place. (C) 2003 Elsevier Ltd. All rights reserved.