双螺杆挤压对菠萝蜜种子淀粉消化特性及血糖指数的影响

为探究双螺杆挤压对菠萝蜜种子淀粉(JFSS)的消化特性及血糖指数的影响,采用体外消化试验,考察了JFSS经挤压处理前后的消化性与消化动力学变化,并通过水解指数(HI)、血糖指数(GI),预测了菠萝蜜种子淀粉的餐后血糖水平(PPBS)。结果表明,双螺杆挤压增加了快速消化淀粉(RDS)与慢消化淀粉(SDS)含量,提高了平衡浓度(C∞)、酶解速率(k)、水解指数(HI)、血糖指数(GI)和淀粉消化率,显著降低了抗性淀粉含量(RS)(P<0.05)。在低水分含量下,增加螺杆转速与机筒温度,RDS含量由47.85%增加到58.91%,且k、C∞、HI、GI值也均呈现增加趋势,而SDS含量、RS含量呈降低趋势。螺杆挤压使菠萝蜜种子淀粉由致密结构转变为疏松多孔的多面体结构。

Effect of Twin Screw Extrusion on Digestibility and Glycemic Index of Jackfruit Seed Starch

To investigate the effect of twin screw extrusion on the digestion properties of jackfruit seed starch(JFSS)and glycemic index,the changes of the digestibility and digestibility dynamics of JFSS before and after extrusion were investigated by in vitro digestion test. On basis of this,the postprandial blood glucose level(PPBS)of JFSS before and after extrusion was predicted by enzymatic hydrolysis index(HI)and glycemic index(GI). The results indicated that the twin screw extrusion treatment increased the content of rapidly digestible starch(RDS)and slowly digestible starch(SDS),and enhance the equilibrium concentration(C_∞),enzymatic hydrolysis rate(k),hydrolysis index(HI),glycemic index(GI),and digestion rate of JFSS but significantly decreased the content of resistant starch(RS)(P<0.05). Under the low moisture content,with the increase of screw speed and barrel temperature,the content of RDS increased from 47.85% to 58.91%,and the values of k,C_∞,HI and GI also increased. The structure of JFSS changed from the compact structure to loose,porous polyhedral structure by twin screw extrusion.