静磁场辅助冷冻对牛肉品质的影响

Effect of Static Magnetic Field-Assisted Freezing on Beef Quality

为探究静磁场辅助冷冻(static magnetic field assisted freezing,SMAF)对牛肉品质的影响,采用不同强度SMAF(0、2、4、6、8、10 mT,-18℃),对比分析冷冻参数对牛背最长肌品质的影响。结果表明:与对照组相比,SMAF-6、8、10处理组相变时间分别显著缩短15%、25%和6.7%(P<0.05);SMAF处理有效提高了肌肉的持水性(解冻损失率、蒸煮损失率和离心损失率),降低了样品的ΔE(P<0.05),但对样品的pH值和硫代巴比妥酸反应物值无显著影响(P>0.05);此外,剪切力与肌原纤维小片化指数的结果一致,SMAF处理维持了牛肉的剪切力;十二烷基硫酸钠-聚丙烯酰胺凝胶电泳结果显示,SMAF处理可以减少肉品经冷冻-解冻后蛋白质含量的降低。综上,在适当的静磁场强度下辅助冷冻,可节省冻结时间,提高肌肉持水力,减少蛋白质含量的降低,从而改善牛肉品质,其中SMAF-8处理效果最佳。

To investigate the effect of static magnetic field-assisted freezing(SMAF)on beef quality,quality traits of beef Longissimus dorsi muscle frozen at−18℃and different magnetic field intensities(0,2,4,6,8 and 10 mT)were comparatively analyzed.The results showed that compared with the control group,SMAF-6,8,and 10 treatments significantly shortened the phase transition time by 15%,25%,and 6.7%,respectively(P<0.05).SMAF treatment effectively improved the water-holding capacity(WHC)of beef(thawing loss,cooking loss and centrifugal loss),and reduced the color difference(ΔE value)(P<0.05),but had no significant effect on the pH or thiobarbituric acid reactive substance value(P>0.05).In addition,the results of shear force and myofibrillar fragmentation index(MFI)were consistent,indicating that SMAF treatment maintained the shear force of beef.Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE)showed that SMAF treatment could reduce the decrease in protein content of meat after freezing and thawing.In summary,freezing under appropriate static magnetic field intensity(8 mT)can save time,improve the WHC of muscles,reduce the protein loss,and thus improve beef quality.