机械活化玉米淀粉的微生物降解性能

为了提高玉米淀粉的微生物降解反应活性，采用搅拌球磨机对玉米淀粉进行机械活化，以活化时间为60 min的玉米淀粉和原淀粉为原料，酒曲为降解试剂进行微生物降解反应，并以降解产物的葡萄糖值（Dextrose Equivalent，DE）为评价指标，分别研究了糊化温度、pH值、淀粉浓度、降解时间、降解温度、酒曲培养液用量等因素对降解产物中葡萄糖值的影响，并采用扫描电镜对淀粉降解过程中的颗粒进行形貌观察。结果表明，机械活化预处理能提高玉米淀粉微生物降解反应液中葡萄糖的含量，且活化淀粉未经糊化就能直接被微生物降解，降解60 min时的DE值为36.76%，与原淀粉相比，提高了27.80个百分点。说明机械活化作用破坏玉米淀粉紧密的颗粒表面和结晶结构，有效地提高了微生物降解反应活性。

Degradative characteristics by microorganisms of mechanical activated maize starch

In order to improve the degradation reaction activity of microorganisms of maize starch, maize starch was mechanically activated by a stirring-type ball mill, using distillers yeast as the biodegradation reagent, maize starch with 60 minutes of activation time and native starch was degraded. The effects were investigated that gelatinization temperature, pH value, starch concentration, degradation time, degradation temperature and microorganisms fluids dosage influenced on degradation reaction of microorganisms from maize starch, using dextrose equivalent (DE) of the hydrolysis product of starch acetate as evaluating parameter. The morphology of the degrade process of maize starch with mechanical activated was investigated by scanning electron microscope(SEM). The results indicated that the DE increased with mechanical activation, and the maize starch with mechanical activated can be directly biodegradation without a gelatinization. The DE was 36.76% after biodegradation for 60 min, comparing with non-activated maize starch, and the DE increased by 27.80%. Mechanical activation greatly increased degradation reaction activity of microorganisms of maize starch. It indicated that the crystal structure and compact granule surface of maize starch were destroyed by mechanical activation.