冷藏时间对冷却猪背最长肌品质的影响

摘要

Pork longissimus dorsi was taken at 24 h postmortem and stored at 4℃for up to 48 h.At 12 h intervals during the storage period, pH value, color difference, storage loss, cooking loss, shear force and water migration were analyzed. The aim was to examine the effect of cold storage on the quality of chilled pork. The results demonstrated that pH value, yellowness value (b*), storage loss and cooking loss increased significantly (P < 0.05) with storage time, but brightness value (L*) and redness value (a*) did not change significantly (P > 0.05) during the first 24 h of storage. pH value, L* and b*,storage loss and cooking loss were the highest,while shear force was the smallest at 48 h.Low field nuclear magnetic resonance analysis showed that the T2b, T21and T22relaxation times were prolonged significantly (P < 0.05) with storage time; the peak area ratio of T21was decreased, whereas the peak area ratio of T22was increased. To sum up, the quality of pork longissimus dorsi could be maintained for 24 h at 4℃.%以宰后24 h的猪背最长肌为研究对象,研究4 ℃条件下冷藏0、12、24、36、48 h对猪背最长肌pH值、色差、冷藏损失、蒸煮损失、剪切力和水分迁移状态的影响.结果表明:随着冷藏时间的增加,猪背最长肌的pH值、黄度值(b*)、冷藏损失率和蒸煮损失率均显著提高(P<0.05);亮度值(L*)和红度值(a*)在冷藏24 h内差异不显著(P>0.05);冷藏48 h时,猪背最长肌的pH值、L*、b*、冷藏损失和蒸煮损失最大,剪切力最小;低场核磁共振结果表明,随着冷藏时间的增加,T2b、T21和T22起始弛豫时间显著延长(P<0.05),T21的峰面积比例降低,T22的峰面积比例增加.综上所述,4 ℃条件下冷藏24 h以内有利于保持猪背最长肌的品质.