【摘要】 针对鲜切西蓝花冷藏期间的黄化衰老、微生物腐败问题,研究电子束辐照的保鲜和杀菌效果。采用0.03 mm厚聚乙烯保鲜袋(PE)、0.02 mm厚聚氯乙烯保鲜袋(PVC)、一次性聚丙烯保鲜盒(PP)3种不同材料包装鲜切西蓝花,分别经0 k Gy(未辐照)、2.4 k Gy、4 k Gy电子束辐照后于4℃±1℃下冷藏30 d,定期检测黄化率、失重率、腐烂率、花球坚实度、总叶绿素含量、组织相对电导率、菌落总数、霉菌和酵母、大肠菌群。结果表明:电子束辐照可抑制鲜切西蓝花冷藏期间菌落总数、霉菌和酵母的增加,有效杀灭鲜切西蓝花初始携带的大肠菌群,减少黄化发生和总叶绿素含量下降幅度。采用0.02 mm厚PVC保鲜袋结合2.4 k Gy辐照处理效果最佳,4℃冷藏18 d时,鲜切西蓝花的黄化率为2.2%,失重率小于1.3%,花球坚实度为入贮初值的82.3%,总叶绿素含量为11.5 mg∕[(100 g)FW],是入贮初值的84.6%,组织相对电导率较入贮初值升高26.6%,无腐烂发生,无大肠菌群检出。2.4 k Gy电子束辐照有效提高了冷藏鲜切西蓝花的贮藏品质,延长了其保鲜期。更多还原

【Abstract】 Aiming at the undesirable yellowing and microbial corruption of fresh-cut broccoli during cold storage,electron beam irradiation was applied to fresh-cut broccoli cold stored in different packages,and its effectiveness for preservation and sterilization were investigated.Fresh-cut broccoli flower packed in 0.03 mm thick polyethylene bag(PE),0.02 mm thick polyvinyl chloride bag(PVC)and disposable polypropylene fresh-keeping box(PP)were irradiated by 0 k Gy(non-irradiated),2.4 k Gy and 4 k Gy electron beam respectively and stored for30 days at 4 ℃ ±1 ℃,and the yellowing rate,weight loss rate,decay rate,firmness,total chlorophyll content,relative electronic conductivity,total bacterial counts,mould and yeast,coliform bacteria were detected regularly.The results showed that electron beam irradiation could inhibit the growth of total bacterial counts,mould and yeast during cold storage of fresh-cut broccoli,and effectively kill the initial coliform bacteria carried by fresh-cut broccoli.Electron beam irradiation also inhibited the yellowing and decrease of total chlorophyll content of fresh-cut broccoli during cold storage. 0.02 mm thick PVC bag combined with 2.4 k Gy irradiation was superior to other treatments.At the eighteenth day of cold storage,the yellowing rate was 2.2%,the weight loss rate was less than1.3%,the firmness was 82.3% of the initial value,the total chlorophyll content was 11.5 mg∕[(100 g)FW],which was 84.6% of the initial value,and the relative electronic conductivity increased by 26.6% compared with initial value. No decay occurred and no coliform bacteria were detected. 2.4 k Gy electron beam irradiation effectively improved the storage quality of fresh-cut broccoli and prolonged the cold storage life.更多还原