壶瓶枣干燥预处理及提取工艺对其多糖得率的影响

Effects of Drying Pretreatments and Extraction Method on the Polysaccharides Yield of Ziziphus jujube Mill. cv. Hupingzao

本文考察了不同的干燥预处理手段(烘箱干燥和真空冷冻干燥)及减压内部沸腾法中各因素(真空度、温度、液料比和提取时间等)对壶瓶枣多糖及蛋白质得率的影响。实验结果表明:干燥方式对原料枣粉的色差和多糖、蛋白质含量均有显著影响,对含水量无明显影响;真空冷冻干燥所得的枣粉色差小、多糖含量高、蛋白质含量低,综合考虑,选用真空冷冻干燥作为原料预处理手段;减压内部沸腾法最佳工艺参数为体系内温度60℃,液料比50∶1(mL∶g),提取时间30 min,此时外界温度为71℃,真空度为80 kPa,此条件下多糖及蛋白质得率分别为26.05 mg/g和2.14 mg/g;与传统热浸提相比,有效物质多糖得率提高了16.66%。

The effects of drying pretreatments （ oven drying and vacuum freeze drying） and factors of reduced pressure boiling method （ vaeuum degree, temperature, water/solid ratio, extraction time, et al. ） on the pelysaeeharides and pro- tein yield of Ziziphus jujube Mill. ev. Hupingzao were investigated in this study. The result showed that drying methods had significant effects on color differenee of jujube powder and its pelysaeeharldes and protein yields ,but little effect on moisture content. With comprehensive consideration, vacuum freeze drying was a better method for jujube drying pretreatment with lower color differenee and protein yield as well as higher polysaecharides yield. The optimum extraction conditions of reduced pressure boiling method were：system temperature of 60℃, water/solid ratio of 50：1 （mL： g）, time of 30 rain, vacuum degree of 80 kPa, external temperature of 71 ~C. Under these eonditiorts, the protein and polysaeeharides yields were 2.14 mg/g and 26.05 mg/g, respectively. Compared with traditional water extraetion, the pelysaeeharides yield, was improved by 16.66%.