固态发酵食醋醅真空冷冻干燥工艺优化

Optimization of vacuum freeze-drying process for solid-state fermentation of Cupei

以苦荞为原料,辅以沙棘果渣、杜仲叶和燕麦麸皮,以老陈醋传统酿造法制得的醋醅,经真空冷冻干燥、粉碎后制得醋粉。设置升华温度、解析温度、物料厚度为三个评价因素,以干燥速率和干燥醋醅总酸含量为响应值,经单因素和响应面试验,优化醋醅冻干工艺,确定最佳工艺条件为升华温度29℃,解析温度33℃,物料厚度3 cm。该优化冷冻干燥条件下,醋醅干燥速率为3.67%/h,干醅总酸含量为8.71 g/100 g,为后续的相关冻干研究提供了理论基础。

With tartary buckwheat as raw material,supplemented with seabuckthorn pomace,Eucommia ulmoides leaves and oat bran,Cupei was prepared from fermented grains by the traditional brewing method of aged vinegar.After that,vinegar powder was prepared by vacuum freeze-drying and crushing of Cupei.With sublimation temperature,resolve temperature and material thickness as evaluation factors,setting drying rate and total acid content of dried Cupei as response values,the freeze-drying process of Cupei was optimized through single factor and response surface tests.The optimal process conditions were as follows:sublimation temperature 29℃,resolve temperature 33℃,and material thickness 3 cm.Under these optimal freeze-drying conditions,the drying rate of Cupei was 3.67%/h,and the total acid contents of dried Cupei was 8.71 g/100 g,which provided a theoretical basis for subsequent related freeze-drying research.