【作者】 高慧；

【导师】 潘丽军；

【作者基本信息】 合肥工业大学 ， 农产品加工及贮藏工程， 2007， 硕士

【摘要】 淀粉是一种来源丰富的可再生性资源，是植物光合作用的产物。原淀粉具有的特性使其在生命活动和工业生产中都有着广泛的用途。但天然淀粉具有许多性质上的不足之处，如不溶于冷水、淀粉糊易老化脱水、被膜性差、抗剪切性低、稳定性差等。因此，可通过改性来改变原淀粉的固有性质，使之适应生产需要。本文对磷酸盐酯化改性前后的玉米淀粉的糊透明度、冻融稳定性、凝沉性、粘度、溶解度以及膨润力等理化性质进行了对比试验研究，并按照《食品安全性毒理学评价程序和方法》对淀粉磷酸单酯（SPM）进行了急性毒性试验和遗传毒性试验，最后将其作为稳定剂加入到凝固型酸奶中，探讨其对成品酸奶品质的影响。试验研究的主要结论如下：1．通过改性制备的淀粉磷酸单酯取代度为0.0138±0.0001，红外光谱在相应谱带区出现的特征吸收峰，说明淀粉分子确实引入了P=O双键及P-O-C基团。2．淀粉磷酸单酯的糊透明度是原淀粉的4.8倍，冻融稳定性较原淀粉有很大改善；酯化反应可以减弱糊的凝沉倾向；改性后淀粉的溶解度和膨润力分别较原淀粉增长了6.5倍和1.8倍；原淀粉经酯化改性后粘度值增加很多，且其值随剪切速率的升高而急剧降低，具有剪切变稀现象，呈现假塑性流体的特征。3．急性毒性研究：小鼠急性经口毒性试验未见明显症状，也无死亡；淀粉磷酸单酯对雌雄小鼠经口LD₅₀大于10.00g／kg体重，属于实际无毒。4．遗传毒理学（致突变作用）研究：Ames试验采用平板掺入法进行，结果呈阴性；小鼠骨髓嗜多染红细胞微核试验的研究发现，在各试验剂量下，实验组动物嗜多染红细胞（PCE）微核出现率、PCE／成熟红细胞（RBC）与阴性对照组的差异均无显著性；小鼠精子畸形率的试验结果也表明，淀粉磷酸单酯3个剂量组的精子畸变率与阴性对照组相比无显著性差异，对小鼠精子无遗传毒性。从毒理学角度出发，可以认为淀粉磷酸单酯对小鼠无毒、无致突变作用。5．SPM在凝固型酸奶中的应用实验得出其适宜添加量为0.2～0.5％，应用效果较好。更多还原

【Abstract】 Nature starch is a kind of reproducible resources, and it is the product of plants’ photosynthesis. It can be extensively used both in life-activity and in industrial production because of the attributes of nature starch. But there are many deficiencies that it is hard to dissolve in cold water, easy to dehydrate, bad film-forming, low shear resistance and weak stability, etc. So it is necessary to modify the nature starch’s attributes to make it suitable to production.Before and after the corn starch was modified by phosphate, the physical and chemical properties such as paste transparency, retrogradation, freeze-thaw stability , viscosity, solubility, and swelling power were studied. According to the requirements of The Toxicological Evaluation Procedure and Method of Food Safety, the acute toxicity test and the genetic toxicity test were carried out in starch phosphate monoester(SPM). At last, the SPM was added to set-style yoghourt, and the qualities of the yoghourt were studied.The degree of substitution (DS) of the SPM had been confirmed to be 0.0138±0.0001. Infrared spectrometry showed that there were peaks at the corresponding area, which indicated that the corn starch had undoubtedly introduced the groups of P=O and P-O-C.The paste’s transparency of the SPM was 4.8 times of that of the nature starch. The freeze-thaw stability of the nature starch had been improved greatly. The starch’s solubility and dilating capability had increased by 6.5 times and 1.8 times respectively after being modified. And the viscosity of the starch had been enhanced much, and fell sharply with the accretion of the shearing rate, which showed the characters of pseudoplastic fluid.Acute Toxicity Test: No visible symptom was observed and no death occurred in mice administrated orally with SPM during the acute toxicity experiment. The medium lethal dose of SPM on mice was more than 10.00g/kg body weight, which indicated there was actually no toxicity according to the standard of toxicity grade classification.Genotoxicology: In Ames test with plate infiltration, SPM showed no mutagenic effects. In mice erythrocyte micronucleus test, no significant difference was observed between SPM treatment groups and negative control group both in the rate of micronucleus in polychromatic erythrocytes(PEC) and the ratio of PEC to mature erythrocyte, which also implied that SPM had no mutagenic effects. Mice sperm malformation test showed that the abnormal sperm rate in treatment group was not different significantly from control group, indicating SPM is of no genetic toxicity.At last, the application of SPM in the yoghourt was discussed. When addition volume of starch was 0.2～0.5%, SPM showed very good effects.更多还原