桑叶多酚对鲜切生菜的保鲜效果  

Effect of mulberry(Morus alba L.)leaf polyphenols on the preservation of fresh-cut lettuce

作　　者：张宏琛 余琳 石慧[1] ZHANG Hongchen;YU Lin;SHI Hui(College of Food Science,Southwest University,Chongqing 400715,China)

机构地区：[1]西南大学食品科学学院,重庆400715

出　　处：《食品与发酵工业》2022年第7期195-200,共6页Food and Fermentation Industries

基　　金：重庆市留学人员创业创新计划优秀项目(cx2019017);中央高校基本科研业务费重点项目(XDJK2020B043)。

摘　　要：桑叶是我国的药食两用农产品,而多酚被广泛认为是一种有较强抗氧化和抗菌能力的天然活性物质,但目前对桑叶多酚开发应用研究仍然较少。该文测定了5种桑叶多酚对大肠杆菌O157∶H7和单核增生李斯特菌的最小抑菌浓度(minimal inhibit concentration,MIC),并选取效果最好的2个品种进行后续实验。为了研究桑叶多酚对鲜切生菜的保鲜效果,分析了鲜切生菜在室温(25℃)储藏4 d期间的品质变化。结果表明,相比于未处理组,MIC下(5 mg/mL)的桑叶多酚处理显著抑制了鲜切生菜中的叶绿素的降解和酚类物质的合成(P<0.05),显著降低了鲜切生菜在储藏期间的褐变度(P<0.05),且纳溪比嘉陵20效果好。同时,2种桑叶多酚显著抑制了鲜切生菜的细菌生长(P<0.05),且嘉陵20比纳溪效果好。综上所述,桑叶多酚能够延缓鲜切生菜在室温储藏期间的品质劣化,有望成为一种新型的天然鲜切果蔬生物保鲜剂。Mulberry(Morus alba L.)leaf is a kind of product with medicine and food homology in China,and polyphenols are widely considered as a natural active substance with excellent antioxidant and antibacterial properties.However,the studies into application of the mulberry leaf polyphenols(MLPs)are still limited.In this study,the minimal inhibitory concentration(MIC)of MLPs from five different cultivars against Escherichia coli O157∶H7 and Listeria monocytogenes was determined,then the best two cultivars were chosen to conduct the following experiments.To investigate the preservation effect of MLPs on fresh-cut lettuce,the quality changes of fresh-cut lettuce during 4-day storage at room temperature(25℃)were analyzed.Compared with the untreated group,the MLP-treated group(under MIC,5 mg/mL)significantly inhibited the degradation of chlorophyll and the biosynthesis of phenolic compounds and reduced the browning degree(P<0.05).In addition,Naxi had a better effect than Jialing 20.Moreover,both MLPs significantly inhibited the growth of bacteria on fresh-cut lettuce(P<0.05),and Jialing 20 performed better than Naxi.In conclusion,MLP can delay the quality deterioration of fresh-cut lettuce during storage at room temperature and promisingly become a novel natural bio-preservative for fresh-cut vegetables and fruits.

关 键 词：桑叶多酚 鲜切生菜 抗褐变 抗菌 生物保鲜剂 

分 类 号：TS255.3[轻工技术与工程—农产品加工及贮藏工程]