真空冷冻与热风联合干燥毛竹笋

对毛竹笋进行真空冷冻与热风联合干燥研究,将得到的产品,分别与热风干燥和真空冷冻干燥的产品比较总的能量消耗和物化特性,确定了真空冷冻与热风联合干燥为较佳的联合干燥方式.较佳转换点为:真空冷冻干燥10.5 h后,转为热风干燥4 h,转换水分质量分数20％.真空冷冻与热风联合干燥的产品在感官、营养、复水比和细胞结构方面明显优于热风干燥的脱水笋片,较接近真空冷冻干燥的产品;同时,真空冷冻与热风联合干燥比真空冷冻干燥节省能耗约21%.

Experimental Studies on Moso Bamboo Shoot Treatment by a Combination Drying of Hot-Airflow and Vacuum Freeze

Moso bamboo shoots were treated by a combination drying of hot-air and vacuum freeze in this work. Energy consumption and physicochemical properties of combination dried products were compared with those of 100% hot-air drying and 100% vacuum freeze drying processes, respectively. It showed that the favorate combined drying method was to use vacuum freeze drying first and then shifit to hot-air, drying at the point when 20% moisture content was reached. The combination dried products of vacuum freeze and hot-air were superior to hot-air dried products on appearance, nutrition, rehydration ratio and cell structure aspects and closed to that treated by vacuum freeze dried method. Furthermore, the combined drying process saved 21% energy consumption compared with the energy cost using 100% vacuum freeze drying process.