不同保鲜袋对意大利生菜的保鲜效果

Fresh keeping effect of different fresh packing bags on Italian lettuce

目的筛选出适宜云南生菜保鲜的包装。方法分别采用FM、GJ4、GJ2、GZ2和CK等5种包装,通过贮藏中感官评价、含水量、相对电导率值的变化趋势,研究其对生菜保鲜效果的影响。结果贮藏到7d,FM、GJ4、GJ2、GZ2和CK的感官评分分别为6.25、6.25、6.00、6.25和6.00,均高于临界值(5),即所有保鲜袋均能在7d内较好的维持生菜的商品性。贮藏13d生菜的含水量为FM(91.31%)>GJ4(91.20%)>GZ2(91.12%)>GJ2(91.07%)>CK(90.72%),与材料厚度FM(2.5~3丝)、GJ4(4丝)、GZ2(2丝)、GJ2(2丝)和CK(1.5丝)基本成正比;Vc含量由高到低分别为:FM(52.98 mg/100 g·Fw)>GJ2(50.90 mg/100 g·Fw)>GZ2(49.60 mg/100 g·Fw)>CK(44.67 mg/100 g·Fw)>GJ4(38.18 mg/100 g·Fw);厚度较低的CK和较大的GJ4保鲜袋的相对电导率值分别为6.86%和5.77%,高于FM(5.04%)、GZ2(4.81%)和GJ2(5.37%),说明保鲜袋厚度对生菜保鲜效果存在较大影响。结论FM保鲜袋厚度适中,贮藏13 d能够较好的保持生菜贮藏中的Vc含量(52.98 mg/100 g·Fw)和水分含量(91.31%),维持较低的相对电导率值(5.04%),是生菜包装的最佳选择。

Objective To select the fresh-keeping packaging suitable for the preservation of Yunnan lettuce.Methods Totally five kinds of packaging,including FM,GJ4,GJ2,GZ2 and CK,were used to study the effect of lettuce on freshness through the changes of sensory evaluation,water content and relative conductivity during storage.Results After 7 days of storage,the sensory scores of FM,GJ4,GJ2,GZ2 and CK were 6.25,6.25,6.00,6.25 and 6.00 respectively,which were all higher than the critical value(5),and all fresh-keeping bags could maintain the commerciality of lettuce in 7 days.The water content of lettuce in 13 days of storage was FM(91.31%)>GJ4(91.20%)>GZ2(91.12%)>GJ2(91.07%)>CK(90.72%),which was basically positively proportional to the material thickness of FM(2.5-3 wires),GJ4(4 wires),GZ2(2 wires),GJ2(2 wires)and CK(1.5 wires).The contents of Vc from high to low were:FM(52.98 mg/100 g×Fw)>GJ2(50.90 mg/100 g×Fw)>GZ2(49.60 mg/100 g×Fw)>CK(44.67 mg/100 g×Fw)>GJ4(38.18 mg/100 g×Fw).The relative conductivity values of CK with lower thickness and GJ4 plastic bag with larger thickness(6.86%and 5.77%,respectively)were higher than those of FM(5.04%),GZ2(4.81%)and GJ2(5.37%),indicating that the thickness of plastic bag had a great influence on the fresh-keeping effect of lettuce.Conclusion The thickness of FM fresh keeping bag is moderate,which can keep the Vc(52.98 mg/100 g·Fw)content and moisture(91.31%)content and the relatively low conductivity(5.04%)of the lettuce in 13 d storage,which is the best choice for the packaging of the lettuce.