喷雾干燥法制备G型低聚果糖干粉及其干粉性质的研究

β-果糖基转移酶转化蔗糖水溶液生成的G型低聚果糖（以下称G-FOS；FOS纯度50％～60％）中，伴有25％～32％葡萄糖及1％～3％果糖生成。在对G—FOS喷雾干燥过程中葡萄糖和果糖很容易吸湿并结块粘壁，而且G—FOS熔点（约62℃）低，在高温干燥过程中易成熔溶态而难以制得干粉。针对这两个难题，以离心式压力喷雾干燥器进行喷干试验，通过正交设计及分析得到的喷雾干燥控制参数为：料液浓度为30％，进风温度为140℃，出风温度为90℃，进风量为40L／s，可制得74～350μm粉状产品，收率约85％．G—FOS干粉在RH≤45％环境放置3天不结块。同时还对G—FOS干粉流动性、回潮时间等性质进行了初步研究。

Preparation of G- FOS Powder by Spray Drying and Study on Characteristics of Powder

The G -fructooligosaccharide （hereinafter referred to the G-FOS; purity of FOS 50% - 60%） is produced from sucrose by β -fructosyltransferase, and the main byproducts is glucose（25%-32% syrup）and Fructose（1% -3%）. During the spray drying process of G-FOS, the glucose and fructose will agglomerate and caking the wall, as it can absorb moisture easily. And the melting point of G-FOS is so lower （about 62℃ ）that it will be dissolved into melting system easily during the high temperature drying process, so it is difficult to obtain the dry powder products. Aimed at the two problems above, a spray drying experiment with centrifugal pressure spray dryer was carried through. Tested by orthogonal design and analysis, the obtained spraying dry condition parameters were concentration of G-FOS of 30wt.%, inlet temperature of spray drying of 140℃, outlet temperature of spray drying of 90℃, air intake volume of 40L/s, diameter of powder products of 74 - 350μm, and the recovery approximate of 85%. The powder products will not be agglomerate, and have a good fluidness, within 3 days in the environment（RH≤45%）. Also preliminary studies on the fluidity of G-FOS power properties and the time of moisture regain etc have been carried through.