限制性酶解与喷雾干燥制备婴幼儿米粉及其体外消化性和流变性研究

In Vitro Digestibility and Rheological Properties of Infant Rice Powder Produced by Limited Hydrolysis and Spray Drying

以米浆DE值为指标,采用高温α-淀粉酶通过单因素试验和正交试验优化酶解工艺,确定婴幼儿米粉最佳酶解条件为酶添加量0.13%、酶解温度95℃、底物浓度(w/v)15%、酶解时间100 min,在该条件下,米浆DE值为27.20。利用限制酶解-喷雾干燥制备不同DE值的婴幼儿米粉,探讨不同酶解程度婴幼儿米粉DE值对其微观形态、功能特性及流变学性质的影响,结果表明:DE值增大使酶解米粉的溶解度指数提高,而水合能力、快速消化淀粉含量和米粉溶液的黏度有一定的下降。与市售米粉比较,酶解婴幼儿米粉溶解度指数显著增加,水合能力降低,淀粉消化率提高,黏度显著降低。α-淀粉酶限制酶解-喷雾干燥制备工艺,改善了传统加工工艺制备的婴幼儿米粉溶解度差,调糊黏度大,难以消化等问题。

The limited hydrolysis conditions for processing infant rice serous fluid were optimized by single factor and orthogonal experiments using DE value as the target index. The optimal parameters of α-amylase 0.13%(dry base),hydrolysis temperature 95 ℃, substrate concentration 15% and hydrolysis duration 100 min could cause DE of rice serous fluid up to 27.20. Then various DE level’s infant rice flours were prepared by spray drying at optimal limited hydrolysis parameters by changing the hydrolysis duration at 10 min, 40 min, 70 min, and 100 min, respectively. The effects of DE value on the morphology, functional and rheological properties of infant rice flour were investigated. The results showed that the solubility increased along with the increase of the DE value, yet the hydration capacity, RDS content and viscosity of the rice flour paste showed a reversed trend. Compared with commercial sample, hydrolysed infant rice powder had a significant increase in solubility, in vitro digestibility, and both hydration index and viscosity decreased. The limited hydrolysis plus spray drying treatments could improve the quality of infant rice powder in higher digestibility, higher solubility, and lower viscosity.