洋葱粉微切、真空干燥工艺研究

Study on microcut and vacuum drying technology in onion powder

以金昌优质洋葱为原料,采用单因素对比分析结合响应面法研究微切、真空低温干燥技术对洋葱粉营养成分(芦丁、槲皮素、维生素的含量)及综合感官指标的影响。结果表明:在微切转速9000r/min(即颗粒直径0.00127mm)、干燥前浓度50%、干燥真空度23mbar、五段真空干燥温度为38、35、30、25、5℃的最优条件下,产品感官指标最优,且芦丁含量为0.57mg/g,槲皮素含量达到4.033mg/g,比市售喷雾干燥法生产的洋葱粉中芦丁高26倍,槲皮素高42倍,维生素E、维生素A含量也高出一倍左右。

Jinchang local excellent onion as the raw material,the effect of microcut and vacuum low-temperature on nutritional components（especially rutin,quercetin and vitamins）and comprehensive evaluation value were studied by contrast analysis of single factors and Box-Behnken Design.The results showed that the best technological parameters were： microcut speed 9000r/min （ microcut grain size 0.00127mm）, concentrated hydrolysates 45% - 50% before drying,drying vacuum 23mbar and with the five drying temperature of 38,35,30,25,5℃.Under this condition,the sensory indexes of onion power products were the best.With the rutin and quercetin content of 0.57mg/g and 4.033mg/g,which was twenty-six times and fouty-two times higher than the onion power product for sale in market produced by spray drying, separately.The content of vitamin A and vitamin E in onion powder increased more than one time compared with spray drying products.