褪黑素对羊肉抗氧化、肉品质及货架期的影响

Effect of Melatonin on Antioxidant,Meat Quality and Shelf Life of Mutton

[目的]研究褪黑素(melatonin, MT)对羊肉抗氧化能力和肉品质的影响,探究MT在体外条件下是否具有改善肉品质和延长货架期的能力。[方法]选取体重相近(36.23 kg±0.31 kg)的5月龄湖羊,采集背最长肌分割后随机分为4组,对照组羊肉浸泡在蒸馏水中,试验Ⅰ、Ⅱ、Ⅲ组羊肉分别浸泡在含3、6和9 ng/mL MT的溶液中,30 min后沥干装入自封袋4℃贮存,在试验第1天对其MT含量进行测定,在试验第1、4、7、10和13天对其抗氧化能力和肉品质进行测定,并在试验12、36、84、132、180、228 h测定羊肉中挥发性盐基氮(total volatile base nitrogen, TVB-N)含量。[结果]与对照组相比,试验Ⅰ、Ⅱ和Ⅲ组羊肉MT含量极显著升高(P<0.01);在试验第1、4、7天试验Ⅲ组羊肉总抗氧化能力(T-AOC)显著升高(P<0.05),试验Ⅱ、Ⅲ组羊肉丙二醛(MDA)含量极显著降低(P<0.01);在试验第7、10、13天试验Ⅱ、Ⅲ组羊肉pH显著降低(P<0.05),试验Ⅰ组羊肉滴水损失极显著降低(P<0.01),试验Ⅰ、Ⅱ和Ⅲ组羊肉货架期分别延长9.11、12.89、14.91 h。[结论]MT在体外具有一定提高羊肉抗氧化和改善肉品质的能力,且可以延长羊肉货架期,建议添加浓度为3 ng/mL。

[Objective]This experiment was aimed to study the effect of melatonin(MT)on the antioxidant capacity and quality of mutton,and investigate whether or not MT could improve the quality of mutton and extend shelf life in vitro.[Method]Five-month-old Hu sheep with similar body weight(36.23 kg±0.31 kg)were selected,and the longissimus dorsi muscle was collected and randomly divided into four groups.The mutton in control group was soaked in distilled water,and the mutton in experiment groupsⅠ,ⅡandⅢwere soaked in the solution containing 3,6 and 9 ng/mL MT,respectively.After 30 min,it was drained and stored in a self-sealing bag at 4℃.The MT content was measured on the first day of the experiment.The antioxidant capacity and meat quality were measured on the 1st,4th,7th,10th and 13th days of the experiment.The total volatile base nitrogen(TVB-N)content in mutton was measured at 12,36,84,132,180 and 228 h of the experiment.[Result]Compared with control group,the MT contents of mutton in groupsⅠ,ⅡandⅢwere extremely significantly increased(P<0.01).On the 1st,4th and 7th days of the experiment,the total antioxidant capacity(T-AOC)of mutton in groupⅢwas significantly increased(P<0.05),the malondialdehyde(MDA)contents of mutton in groupsⅡandⅢwere extremely significantly decreased(P<0.01).On the 7th,10th and 13th days of the experiment,pH of mutton in groupsⅡandⅢwas significantly decreased(P<0.05),the drip loss of mutton in groupⅠwas extremely significantly decreased(P<0.01),the shelf life of mutton in groupsⅠ,ⅡandⅢwas extended by 9.11,12.89 and 14.91 h,respectively.[Conclusion]MT could improve the antioxidant capacity and quality of mutton in vitro to a certain degree,and extend the shelf life of mutton.In summary,this study recommended 3 ng/mL as the optimal concentration of MT.