复合保鲜剂结合MAP对鲜切茄子贮藏品质的影响

Effect of chitosan compound preservative combined with modified atmosphere packaging on quality of fresh-cut eggplant during storage

为延长鲜切茄子的保鲜时间,研究单一气调包装(2%CO2+5%O2+93%N2)和保鲜液(1.5%壳聚糖+1%抗坏血酸+1%氯化钙+2%柠檬酸)结合气调包装对鲜切茄子品质的影响。以感官评分、褐变度、硬度、多酚氧化酶(PPO)活性和细菌总数为指标,分析鲜切茄子于(10±1)℃下贮藏8d内的品质变化。结果表明:贮藏8d后,对照组样品的L*值、硬度、PPO酶活性和细菌总数分别为75.66、7.41kg/cm2、68.77U/(min·g)和5.52lg CFU/g,而经保鲜液结合气调包装的鲜切茄子各指标分别为82.51、10.05kg/cm2、23.70U/(min·g)和2.87lg CFU/g。气调包装能够抑制鲜切茄子的褐变、萎蔫等感官品质的下降,并抑制PPO活性的增加和细菌的生长繁殖,尤其在结合保鲜液处理后效果更加明显,贮藏8d仍保持较好的品质。

Fresh-cut eggplant is popular with consumers because of its instance and hygiene, however, its shelflife is limited. To prolong the shelflife of fresh-cut eggplant, the effects were studied for modi- fied atmosphere packaging （MAP, 2 % CO2 ＋ 5 % O2 ＋ 93 % N2 ） and the combined treatment of preservative solution （1. 5% chitosan＋ 1.0% ascorbic acid＋ 1% CaCl2 ＋2% citric acid） and MAP on the quality of fresh-cut eggplant. The quality indices including sensory quality, browning degree, firmness, polyphenoloxidase （PPO） activ- ity and total bacterial counts were detected during 10 days of storage at （10±1） ℃. After 8 days of storage, the L＊ value, firmness, PPO activity and total bacterial counts of the control sample were 75.66, 7.41 kg/cm2, 68.77 U/（min · g） and 5. 52 lg CFU/g, re spectively. While the quality indices of the samples treated by the combined treatment were 82.51, 10.05 kg/cm2 , 23.70 U/（min·g）and 2.87 1g CFU/g. The results indicated that MAP retarded the browning and softening of eggplant slices and the coating treatment prior to MAP enhanced the effectiveness. The fresh cut eggplant treated by coating and MAP were still acceptable for cooking after 8 days of storage.