不同含量脱氢乙酸钠改性PVA薄膜 延长蛋糕保质期的研究

研究了不同脱氢乙酸钠含量的P V A薄膜对蛋糕保质期的影响,以得出最适于蛋糕保鲜用改性包装薄膜。首先,用流延法制备出以不同质量分数脱氢乙酸钠改性的P V A改性薄膜,然后将待测蛋糕切成一定规格并分别装入不同的PVA薄膜包装袋中进行贮藏试验。且每隔3 d,对样品蛋糕进行感官评价,并检测其失重率、菌落总数、酸价、过氧化值等,以评价改性包装的抑菌及抗油脂氧化效果。结果表明,添加脱氢乙酸钠改性后的PVA薄膜的保鲜效果均优于未改性PVA薄膜的;综合各因素的影响结果,确定添加质量分数为2%脱氢乙酸钠的改性PVA薄膜对蛋糕的保鲜效果较好,其不仅能有效阻止蛋糕中水分的流失,且蛋糕的抗氧化性能最强。

Extending Shelf Life of Cakes with PVA Films Containing Different Sodium Dehydroacetate

The effects of PVA films containing different amount of sodium dehydroacetate on cake shelf life were studied to identify the most suitable modified packaging films for preserving cakes. The PVA active films modified with different mass fraction of sodium dehydroacetate were prepared by casting method. The cake was cut into certain sizes and put into different PVA film packaging bags for storage test. The sensory evaluation of the cake was made every three days on the weight loss rate, the total bacterial count, acid value, peroxide value to evaluate the antibacterial and antioxidant effect of the modified packaging. The results showed that the preservation effects of modified PVA films with sodium dehydroacetate were better than that of unmodified PVA film; a favorable fresh-keeping effect was achieved by modified PVA film with mass fraction of 2% sodium dehydroacetate after summarizing all influencing factors as the loss of moisture in the cake could be effectively prevented with the strongest antioxidant performance.