壳聚糖降解液对鲜切莴笋的防腐保鲜效果

用常温水解壳聚糖得到的粘均相对分子质量Mv在1500～2000的降解液、结合热处理对鲜切莴笋进行保鲜试验。结果表明,采用质量分数50%的壳聚糖降解液、45℃浸泡2min的处理方法,鲜切莴笋的微生物生长以及褐变被明显抑制,在贮藏期9d内,细菌总数在106cfu/g左右,PPO活性峰值比对照降低46%,Vc含量高于对照56%,感官品质保持良好。

Effect of Liquid Chitosan-degraded in the Preservation and Antisepsis of Fresh-cut Lettuce

Tests of fresh-cut lettuce preserving were carried out using a liquid of degraded chitosan (Mv=1?500～2?000) as preservation agent and heat treatment. The results showed that a better keeping-fresh treatment method could be developed by soaking fresh-cut lettuce in 50% liquid chitosan-degraded, at 45℃ for 2 minutes. When stored at (4±0.5)℃ for 9 days, the number of total bacteria was about 106 cfu/g, the PPO's activity were lowed down by 46%,and the Vitamin C was 56% higher than that in control. The microorganism growth and browning was obviously inhibited, and the sensory evaluation of fresh-cut lettuce was still in good condition.