Relationships between sensory perception and water distribution determined by low-field NMR T2 relaxation in processed pork - impact of tumbling and RN− allele

The relationships between water distribution, measured with low-field NMR (LF-NMR) transverse (T2) relaxometry and sensory properties in tumbled and non-tumbled cured-smoked loins from 30 female Hampshire crossbred pigs were investigated. Upon distributed analysis of the T2 relaxation, three populations centred at about 2, 40 and 600-800 ms, respectively, were detected. Clear differences in the characteristics of the intermediate population (T21) were observed between loins from carriers and non-carriers of the RN− allele, which implies differences in water-protein interactions between the two genotypes. PLS regressions between NMR T2 variables and sensory attributes revealed significant correlations between NMR T2 variables and the sensory attributes juiciness, acidulous taste and meat taste, which mainly could be ascribed to the T21 time constant. In addition, the number of unappealing pores assessed by the sensory panel was highly related to the relative T2 populations, implying that the microstructure is directly reflected in the NMR T2 populations. However, prediction of the processing yield from NMR T2 variables was poor. The correlation improved when RN genotypes and tumbling conditions were included as predictors. Thus, other effects of tumbling treatments and RN genotypes unrelated to NMR T2 relaxation were observed.