滩羊肉宰后贮藏期间色泽稳定性的变化OA

This study attempted to explore the impact of different storage periods on the color stability of postmortem Tan sheep(Ovis aries)meat.The longissimus dorsi muscle of Tan sheep slaughtered at the age of 6 months was stored at 4℃and evaluated for color stability-related indicators after 0,1,2,3,4,6,and 8 d.The results showed that during 0-8 d of storage,the pH value of Tan sheep meat first significantly decreased and then significantly increased(P<0.05),with the lowest level occurring on the third day.In contrast,the brightness value(L*),redness value(a*),yellowness value(b*),and R630 nm/R580 nm all initially significantly increased and then significantly decreased(P<0.05).The relative content of metmyoglobin(MetMb)first significantly decreased and then significantly increased(P<0.05),the relative content of oxymyoglobin(OxyMb)significantly increased initially and then significantly decreased(P<0.05),and the relative content of deoxymyoglobin showed an overall downward trend(P<0.05).The activity of metmyoglobin reductase and the content of reduced nicotinamide adenine dinucleotide(NADH)both showed a significant downward trend(P<0.05);the activity of lactate dehydrogenase(LDH)significantly increased during the first 4 d of postmortem storage(P<0.05),reaching its maximum on the fourth day,and then significantly decreased in the later storage period(P<0.05).Long-term exposure of myoglobin(Mb)to oxygen in air and the reduction in the content and activity of reducing substances in the muscle during post-mortem storage caused irreversible oxidation of OxyMb to MetMb,which in turn affected the L*,a*,and b* of the meat,ultimately causing meat discoloration.This process was regulated by the changes in muscle pH value.The outcomes of this study provide theoretical guidance for improving the theory on the postmortem color stability of Tan sheep meat and for optimizing its quality control,processing,storage,and transportation technologies.