延迟预冷对芥蓝冷链过程品质和营养的影响

Effect of delayed precooling on quality and nutrition of kale in cold chain circulation process

【目的】研究延迟预冷对芥蓝冷链流通效果的影响,为规范预冷操作、冷链应用提供指导。【方法】以芥蓝为试验材料,阴凉堆货0、1、5、9 h后分别压差预冷至3℃,进行有/无膜包装的0℃贮存3 d、0℃运输2 d、4℃销售2 d冷链流通,测定各流通环节品质和营养指标。【结果】堆货9 h芥蓝中心温度升高了4.6℃,呼吸强度增大1倍以上,导致预冷时间延长。延迟预冷0、1 h膜包装组感官评价为8.2、7.8,失质量率为2.84%、3.39%,TSS含量为6.39%、6.22%,VC含量为0.944、0.900 mg/g,叶绿素含量为772.3、749.4μg/g,短时间延迟预冷品质下降较小;无膜包装贮藏3 d后各组失质量率均已超过4%,其他营养和品质损失也更高。【结论】延迟预冷时间越短越好,芥蓝应在采后1 h内预冷并结合膜包装冷链流通。

【Objective】In order to explore the effect of delayed precooling time on the storage of kale in cold chain,and to provide guidance for standardizing precooling and cold chain operation.【Method】Postharvested kale were put in a lightless space for 0,1,5 and 9 hours,then implemented differential precooling to 3℃separately,and proceeded the cold chain circulation with and without anti-fog film packaging(cold storage at 0℃for 3 days,transportation at 0℃for 2 days,and sales at 4℃for 2 days),the quality and nutrition indexes of each stage were determined.【Result】The central temperature of kale increased by 4.6℃after 9 hours of storage,the respiratory intensity increased more than 2 times causing the precooling time to be prolonged.Delayed precooling 0 hour and 1 hour with film packing,sensory evaluation was 8.2 and 7.8,weight loss was 2.84%and 3.39%,the contents of TSS,chlorophyll and VC were 6.39%and 6.22%,772.3μg/g and 749.4μg/g,0.944 mg/g and 0.900 mg/g respectively,the kale quality under short time delayed pre-cooling decreased slightly.After 3 days storage without film packaging,the weight loss rate of each group was more than 4%,and the loss of other nutrition and quality was also higher.【Conclusion】The shorter delay precooling time is better,kale should be precooled within 1 hour after harvest and combined with film packaging cold chain circulation.