自发性气调对鲜切茭白品质及微生物的影响

目的]研究不同气调包装材料对鲜切茭白品质及表面微生物的影响。方法]将茭白鲜切处理,置于不同材料的塑料袋包装中,在0~4℃进行自发性气调贮藏,定期检测茭白的色泽、失重率、硬度、电导率、可溶性固形物、还原糖、总糖、酸度以及菌落总数和乳酸菌数。结果]试验表明,贮藏6 d时,3种包装材料对茭白的色泽、失重率,固形物含量变化都有一定的延缓作用;贮藏12 d时,所有处理组茭白的电导率均小于对照组;贮藏16 d时,聚丙烯、高密度聚乙烯包装鲜切茭白硬度低于对照,高密度聚乙烯包装袋茭白还原糖高于对照组,低密度聚乙烯包装袋内茭白总糖高于对照组,所有处理组茭白总酸度均低于对照组;贮藏至22 d时,所有处理组茭白表面的菌落总数和乳酸菌数均少于对照组。结论]高密度聚乙烯、低密度聚乙烯及聚丙烯包装材料对鲜切茭白均有延长保藏期的作用,但也存在差异,自发性气调贮藏对鲜切茭白有延长保质期的作用。

Effects of Modified Atmosphere Packaging on Quality and Microbiological Contamination of Fresh-cut Zizania aquatica L.

Objective] To explore the effects of different membrane packages on quality and microbiological contamination of fresh-cut Ziza-nia aquatica L. Method] Fresh-cut Z. aquatica was sealed selectively in high-density polyethylene bag ( HDPE) , low-density polyethylene bag ( LDPE) and polypropylene bag ( PP) . Modified atmosphere packaging storage was carried out at 0-4 ℃. Then, the color, weight loss, hardness, conductivity, total soluble solid ( TSS) , reducing sugar, total sugar, total acidity and total plate count, lactobacillus number were measured at certain interval, respectively. Result] After 6-day storage, three film packages had certain delaying effects on the changes of color, weight loss ratio and total soluble solid. After 12-day storage, conductivities in Z. aquatica of all treatment groups were all smaller than that of control group. After 16-day storage, the hardness of Z. aquatica sealed in PP and LDPE were lower than that of control;the reducing sugar of Z. aquatica in HDLE was higher than that of control;and the total sugar of LDPE was higher than that of control;all packages were lower than control in total acidity. Z. aquatica of three film packages showed low total plate count and lactobacillus number when it was stored for 22 days. Conclusion] High-density polyethylene bag (HDPE), low-density polyethylene bag (LDPE) and polypropylene bag (PP) all extend the storage period, but there were certain differences. Modified atmosphere packaging has the function of extending the shelf-life.