干法合成硬脂酸小麦淀粉酯的特性研究

Study on Synthesis of Wheat Starch Stearate by Dry Method and Its Properties

以小麦淀粉为原料采用盐酸催化干法合成硬脂酸淀粉酯。考察了均质温度、均质速率和体系pH值对硬脂酸淀粉酯乳化性的影响,以及温度和剪切速率对其粘度的影响,并对产品的颜色、透明度、凝沉性、冻融稳定性等性质进行了研究。结果表明,取代度为0.013 8的硬脂酸淀粉酯的乳化性优于阿拉伯胶,乳化性受pH值影响的变化趋势与阿拉伯胶大致相同,其色差值与阿拉伯胶相当。随着产品取代度的提高,产品颜色变黄,透明度增加,凝沉程度减弱,冻融稳定性下降。

Wheat starch stearate was synthesized by esterification of wheat starch with stearic acid, and hydrochloric acid was added as catalyzer. The effects of temperature, homogenizing rate and pH value on emulsion capacity and the effects of temperature and shearing rate on viscosity were investigated. Furthermore, the product properties, such as color, transparency percentage, retrogradation, freeze- thaw stability were also determined. The results showed that the emulsion capacity of starch stearate is superior to that of arabic gum, with the similar change trend resulting from pH value. Therewith, the chromatism value of starch stearate was similar to that of arabic gum. As DS （degree of sustitution） increased, the color changed into yellow, transparency percentage enhanced, retrogradation weakened, and freeze-thaw stability fell.