变温变压的优化组合对扇贝真空冷冻干燥过程影响的实验研究

为了获得调压调温的优化组合对栉孔扇贝真空冷冻干燥过程的品质、能耗和时间的综合影响,在前期研究的基础上,本文对两次变温和一次变压的温度和压力组合参数进行了五因素四水平的正交组合试验,并以能耗、冻干时间和复水率等三指标的综合加权平分值为指标,得出了各温度和压力条件影响冻干能耗及品质的主次关系为:加热板高温2>干燥室低压>加热板高温1>加热板低温>干燥室高压,各因素的最佳组合是加热板高温1为42℃,高温2为30℃,干燥室低压为25Pa,加热板低温为25℃,干燥室高压为80 Pa,在这个优化组合工艺条件下,扇贝的复水率达到83.7%,与16组实验中的最佳相比,复水率提高了12.20%,能耗下降了2.17%,干燥时间缩短了20%。

Optimization of Vacuum Freeze-Drying Conditions of Scallop

A novel technique was developed for freeze-drying of scallop in vacuum.In the technique,the sample experienced two temperature adjustments,and one pressure regulation.The impacts of the freeze-drying conditions,such as the sample temperature,heating rate,and pressure,on energy consumption and quality of the dried scallop were evaluated.The freeze-drying conditions in vacuum were optimized via the orthogonal combination of test.As compared with conventional freeze-drying,the newly-developed technique resulted in a rehydration rate of the scallop dried under the optimized conditions,up to 83.7%(an increase by 12.20%),a 2.17% reduction of energy consumption,and a 20% decrease of drying time.