催化式红外干法杀青同步脱水对叶菜干燥影响的研究

Study of Infrared Dry-Blanching and Dehydration on Leaf Vegetables

脱水蔬菜加工需要杀青和干燥2个阶段,传统加工方法存在耗水量大、能耗高、产品品质差、污染重等缺点。采用催化式红外干法杀青同步脱水技术,对叶菜类蔬菜(大葱、香葱、紫甘蓝、韭菜、生菜)进行加工处理,分别对蔬菜POD酶活酶钝化情况、水分去除情况和干燥速率情况进行研究;对蔬菜维生素C保留率和颜色等质量指标进行考察。研究表明:5种叶菜类蔬菜经过催化式红外杀青处理后POD酶活残留率稳定在20%左右,达到了预期效果;蔬菜杀青灭酶的同时,去除部分水分,起到干燥的作用;得到不同蔬菜催化式红外最佳杀青工艺条件,在此条件下得到杀青产品质量高。

Blanching and drying are two essential processing steps of dehydrated vegetables.The conventional methods have many disadvantages of time-consuming,high energy consumption,low product quality,as well as heavy pollution to environment.This study investigated the infrared dry-blanching and dehydration on leafy vegetables.The characteristics of vegetables were determined via the measurement of peroxidase(POD)activity,the changes on Vitamin C content and leaf color.The study showed that the POD activities of five selected vegetables were reduced to about 20%of their initial activity with infrared dry-blanching.Meanwhile,infrared dry-blanching also can remove partial moisture from vegetables and retain the high quality.In addition,the optimal conditions of infrared dry-blanching on the five different vegetables were also obtained from this study.