烘烤加工对谷物代餐粉GI值及其理化特性的影响

Effect of Baking on GI Value and Physicochemical Properties of Cereal Meal Replacement Powder

为开发一款适合糖尿病人食用的中低血糖生成指数(GI)的谷物代餐粉,以富硒发芽糙米、红小豆、薏米、苦荞、豆渣和桑叶提取物为原料,以感官评分和GI值加权评分为指标,通过响应面试验优化烘烤加工工艺,探讨烘烤与挤压加工两种加工方式对富硒发芽糙米代餐粉的微观结构、晶体特性、糊化特性、糊化度、冲调性、结块率等理化特性的影响。结果显示,在烘烤时间35 min、烘烤温度140℃、液料比1:1(L/kg)最优条件下,GI值为62.75,感官评分为91.17,加权综合评分最高为60.69。与未加工代餐粉相比,烘烤最优代餐粉与挤压代餐粉相对结晶度下降为15.15和4.28,B型和V型晶型都有所增加,微观结构中圆形淀粉颗粒均减少,不规则颗粒增多;电子鼻综合评价方程中,气味综合得分从高到低依次是烘烤最优代餐粉>挤压代餐粉>未加工代餐粉。实验结论表明烘烤最优代餐粉GI值在55~70之间,属于中低GI范围,适合糖尿病人食用,可推荐作为开发中低血糖生成指数代餐粉的优选加工参数。

This study aimed to develop a medium-low glycemic index(GI)cereal meal replacement powder suitable for diabetic patients using selenium-enriched germinated brown rice,red adzuki beans,barley,tartary buckwheat,bean dregs,and mulberry leaf extracts as raw materials.The baking processing technology was optimized through response surface experiments using sensory scores and GI value-weighted scores as indicators.At the same time,the effects of the two processing methods of baking and extrusion on the microstructure,crystal properties,gelatinization properties,gelatinization degree,brewability,caking rate and other physicochemical properties of selenium-enriched germinated brown rice meal replacement powder were discussed.The results showed that the GI value was 62.75,the sensory score was 91.17,and the highest weighted comprehensive score was 60.69 under the optimal conditions of the baking time of 35 min,the baking temperature of 140℃and the liquid-to-material ratio of 1:1(L/kg).Compared with unprocessed meal replacement powder,the relative crystallinity of baking optimal meal replacement powder and extruded meal replacement powder decreased to 15.15 and 4.28 respectively,and the B-type and V-type crystals increased.The round starch granules in the microstructure of the other two meal replacement powders were reduced and irregular granules were increased.In the electronic nose comprehensive evaluation equation,the comprehensive odor score from high to low was baked optimal meal replacement powder>extruded meal replacement powder>unprocessed meal replacement powder.The experimental conclusion showed that the optimal GI value of baking meal replacement powder was between 55 and 70,which belonged to the medium-low GI range and was suitable for people with diabetes.It can be recommended as the preferred processing parameter for the development of meal replacement powder with a medium and low glycemic index.