发酵型半干罗非鱼片热风和热泵干燥的对比研究

为探寻一个适用于发酵型半干罗非鱼片干燥的方法，以干燥罗非鱼为原料制备发酵型半干鱼，分别采用热风与热泵2种干燥方式对发酵型半干罗非鱼片进行干燥，比较了2种干燥方式对发酵型半干鱼口感、色泽、质构、微观结构、微生物特性的影响。结果显示：热风干燥效率优于低温热泵干燥，其完成罗非鱼片干燥所需时间仅为热泵干燥的一半；但采用热泵干燥鱼片在感官指标、色泽、质构均匀性等方面均优于热风干燥鱼片；热泵干燥鱼片中的总菌数和乳酸菌数分别为1.46×108 cfu/g和1.38×108 cfu/g，热风干燥鱼片中的总菌数和乳酸菌数分别为2.44×108 cfu/g和2.9×107 cfu/g。相对于热风干燥，热泵干燥有助于保存乳酸菌，减少杂菌污染，更加适合于乳酸菌发酵食品的干燥。研究结果可以为乳酸菌发酵食品的干燥加工提供参考。

Hot-air and Heat Pump Drying of Lactobacillus Fermented Half-dry Tilapia Fillets

The fermented half-dry tilapia fillets were dried by hot-air and heat pump in order to find an optimum drying method. The effects of the two drying methods on drying rate, sensory properties, color, microstructure and microbial contents of products were investigated. The results showed that the hot-air drying had a higher efficiency which required just half time of drying by heat pump. But the tilapia fillets dried by heat pump advanced sensory score, color index and uniform texture. The total bacteria count and lactobacillus count of the tilapia fillets dried by heat pump were 1.46×108 cfu/g and 1.38×108cfu/g, respectively, while 2.44×108 cfu/g and 2.9×107 cfu/g when the tilapia fillets were dried by hot-air. The heat pump drying was preferable to preserve lactobacillus, reduce bacterial pollution, which was more suitable for drying lactobacillus fermented half-dry tilapia fillets. The results can provide references for drying process of lactobacillus fermented foods.