波谱特性与淀粉消化行为的关系

Relationship between spectroscopic characteristics and starch digestion behaviors

通过不同的加热方式,以普通玉米淀粉和高直链玉米淀粉为原料制备结构不同的系列淀粉样品,然后采用傅里叶变换衰减全反射红外光谱法(ATR-FTIR)分析技术,测定了不同淀粉样品的波谱图特征吸收峰,结果表明高直链玉米淀粉在热处理过程中其特征吸收峰只发生细微变化,而普通玉米淀粉的波谱图变化显著,其在最高吸收峰处由左低右高形态转变为左高右低形态。综合各特征吸收峰在淀粉结构中的表达含义,提出了淀粉结构因子指数这一概念。该值愈高,则说明淀粉分子排列的有序性愈好。通过测定各个淀粉的消化率,统计显示,淀粉结构因子指数与消化率呈良好线性相关性,进一步说明淀粉颗粒结构是调控淀粉消化性质的决定性因素。

Normal maize starch and high amylose maize starch were used to prepare starches with various structures by means of different heating processes, and then they were analyzed using ATR-FTIR. The characteristic absorbance in spectrum was measured and the results showed that the FTIR spectrum of high amylose starch changed slightly after treatment. However, the normal starch spectrum changed significantly after treatment, and its spectrum changed from the shape of lower at left side and higher at right side to the opposite. The comprehensive meaning of the characteristic absorbance in the spectrum was con- sidered and a new concept expressing starch structural index was put forward. The higher the value, the more organized for starch structure. The starch digestion was measured in vitro and it showed that it has good linear relationship with starch struc- tural index. This further indicates that starch structure is a key factor regulating starch digestion properties.