肠膜明串珠菌复合生物保鲜剂对龙眼果实的保鲜作用

Bio-preservation of longan fruits by complex preservative with Leuconostoc mesenteroides dgnkzx002

以石硖、东丰龙眼(Dimocarpus longan Lour.cv.Shixia,Dongfeng)果实为试材,采用单因素试验测定龙眼的商品率、果实品质及果皮多酚氧化酶(PPO)、过氧化物酶(POD)和超氧化物歧化酶(SOD)的活性;采用与L9(34)正交试验测定果皮SOD的活性,结果显示肠膜明串珠菌dgnkzx002对果皮SOD活性的影响极显著,1.5%乳酸钠影响显著,0.1%壳聚糖+2%柠檬酸影响最小,根据均值分析获得最优复合生物保鲜剂配方为1.72×107 CFU/m L肠膜明串珠菌dgnkzx002+(0.1%壳聚糖+2%柠檬酸)+1.5%乳酸钠。复合生物保鲜剂处理果实的商品率优于对照,TSS含量、Vc含量比贮藏初始分别降低了16%、21.22%,与对照存在显著差异;果皮PPO、POD的活性分别为40、565 U/min·g,优于对照的122、1 920 U/min·g。

To investigate the preservation effects of lactic acid bacteria on Longan fruit （ Dimocarpus longan Lour. cv. Shixia, Dongfeng ） and to develop a complex bio-preservative agent as an alternative to chemicals, this paper optimized the ingredients of the complex bio-preservative agent by single factor experiments and L9 （ 34 ） orthogonal design. Results indicated that L. mesenteroides had extremely significant influence on SOD activity in fruit peel, while 1.5% sodium lactate had a significant impact and the effect of 0.1% chitosan ＋ 2% citric acid was minimun. The complex bio-preservative agent with 1.72 ×10^7 CFU/mL Leuconostoc mesenteroides dgnkzx002 ＋ （ 0.1% chitosan ＋ 2% citric acid ） ＋1.5% sodium lactate had the most stable preservative effects on longan fruits. Results showed that total soluble solids （ TSS ） and vitamin C content of longan fruits treated with the complex bio-preservative agent decreased by 16%, 21.22%, respectively, had significant differences with control. And the activity of PPO and POD in fruit peel were 40 and 565 U/min · g, lower than 122, 1 920 U/min · g in control group.