番茄涂膜保鲜效果评价

Evaluation of Fresh-keeping Effect of Coated Tomatoes

以普通市售大番茄为样品,研究大豆分离蛋白、明胶及添加石蜡的大豆分离蛋白这3种可食性涂膜保鲜剂的保鲜效果.实验中,通过测定几种保鲜剂膜的厚度、水蒸气透过系数、透光率、透氧性、扫描电镜下膜结构,考察涂膜保鲜剂的结构与性质;样品在8~10℃、RH 90%~95%下储藏21 d,考察涂膜前后的失重率、呼吸强度、样品表皮细胞的间隙度及细胞膜透性,以确定使用涂膜保鲜剂对番茄保鲜的作用;通过分析这几种涂膜剂自身结构及保鲜效果,确定最佳涂膜保鲜剂.结果表明:涂膜处理对样品有较好的保鲜效果;添加石蜡的大豆分离蛋白膜的水蒸气透过系数、透氧性、透光率均最小,膜结构最完整,且样品的失重率、呼吸强度、表皮细胞间隙度及细胞膜透性等方面显示其保鲜效果优于其他2种.

Taking common commercial tomatoes as samples,the fresh-keeping effects of three edible coating preservatives,soybean protein isolate,gelatin,and paraffin-added soybean protein isolate were studied.By measuring the thickness of preservative coat,water vapor transmission coefficient,light transmittance,oxygen permeability and membrane structure under SEM,the structure and properties of coating were investigated.Through a 21-day of 8-10℃RH 90%-95%storage experiment,the weight loss rate,respiratory intensity,intercellular space of sample epidermal cells and cell membrane permeability before and after coating were investigated to determine the preservative coating effect.The results show that:the coating treatment has good freshness effect on the sample.Water vapor transmittance,oxygen permeability and light transmittance are all minimal and the membrane structure of paraffin-added soybean protein isolate is most complete.The weight loss rate,respiratory intensity,intercellular space of sample epidermal cells and cell membrane permeability of the samples showed that their preservation effect was better than the other two.