水分活度及干燥方式对余甘子果渣质量的影响

    Effects of different drying methods on Phyllanthus emblica pomace and modeling of relationship between moisture and water activity

    • 摘要: 余甘子果渣中纤维类成分含量丰富,是生产膳食纤维较好的原材料,因鲜渣含有较高的水分和糖分,微生物极易滋生、霉变;为便于余甘子果渣存放和后续加工利用,需确定余甘子果渣合理的贮藏水分活度及干燥方式。试验表明,余甘子果渣水分与水分活度关系式为Y=Exp(0.920-12.312/x+8.194/x2-0.03x),其安全水分活度0.6 对应的安全含水率为10.25%,在此含水率下,微生物难以寄生,有较佳的贮藏效果;4 种干燥方式中,流化床干燥法所用时间最短、为5 min,样品表面疏松多孔,硬度最小、为21 N,其次为真空干燥105℃,热风干燥50℃对产品的聚合度影响最大。

       

      Abstract: Phyllanthus emblica pomace,which was rich in fiber,was beneficial raw material for the production of dietary fiber. Fresh P. emblica pomace with high moisture content was suitable for the bacteria breeding and would be corrupted. In order to decrease resources waste,the appropriate drying method was selected to reduce water content of P. emblica pomace. Under safety moisture content,the pomace storage time would be delayed to apply to dietary fiber processing. Model establishment exhibited the relationship between moisture content and water activity. The model could determine the maximum moisture content at safety water activity. The results showed that the relationship between moisture and water activity was Y=Exp(0.920-12.312/x+8.194/x2-0.03x). The safety water activity was 0.6 and its correspondence moisture was 10.25%. Under 10.25%,microbe was hard to parasitism. Fluidized bed drying method had the shortest time with 5 min. The sample,which was porosity,showed the smallest hardness(21 N),followed by 105℃ vacuum drying sample. Polymerization was significantly affected by the method of 50℃ hot-air drying