预处理方法在食品冷冻干燥中的应用分析

The Analysis of Pretreatment Methods Applied in the Freeze-dried Food

真空冷冻干燥在干制品品质方面优于其他干燥,但由于其能耗较大,应用范围和规模受到一定的限制,干燥前的预处理可以有效改善传热传质,降低能耗。本文综述了预处理方法在食品冷冻干燥中的应用,综合分析了渗透、微波、超声波、真空冷却、高压脉冲电场和冻融等预处理的原理和研究现状,为不同食品物料冷冻干燥预处理方法的选择提供理论依据,并为改善冻干工艺提供参考。

In terms of the quality of dried products, vacuum freeze drying is superior to other drying methods. But the application scope and scale of freeze-drying are limited because of its large energy consumption. Drying pretreatment can effectively improve the heat and mass transfer, reduce energy consumption.This article described the application status of pretreatment methods in the freeze-dried food. The principles of osmosis, microwave, ultrasound, vacuum cooling, high pulsed electric field, freeze-thaw pretreatment methods were analyzed comprehensively. A theoretical basis for the selection of pretreatment methods suited for different food materials and theoretical guidance to improve lyophilization process were proposed.