响应面法优化制备魔芋葡甘聚糖-大豆分离蛋白混合凝胶

为提高多糖-蛋白混合物稳定性，改善彼此性能并探究制备过程中各因素对多糖-蛋白混合凝胶成型及性能的影响，以魔芋葡甘聚糖（konjac glucomannan，KGM）和大豆分离蛋白（soybean protein isolate，SPI）为试材，制成KGM-SPI混合凝胶，研究制备工艺对其凝胶强度和持水性的影响。在单因素试验的基础上，取KGM-SPI总质量分数、KGM与SPI配比、KCl浓度和Ca(OH)2添加量为自变量，凝胶强度为响应值，建立混合凝胶强度的二次回归方程，并通过响应面分析得到优化制备条件为：KGM-SPI总质量分数4.5%、KGM与SPI配比3∶1、KCl浓度0.13 mol/L、Ca(OH)2添加量0.15%。此条件下混合凝胶强度验证值为2.758 N，与预测值2.779 N相近。通过对优化前后凝胶质构特性进行了对比分析，均证实优化结果可靠。

Optimization of the Formulation of Konjac Glucomannan-Soybean Protein Isolate Mixed Gel by Response Surface Methodology

This study aimed to enhance the compatibility of polysaccharide-protein mixtures, to improve their performance
and to study the effects of various factors on gelation and gel properties. The effects of formulation variables on gel strength
and water-holding capacity of konjac glucomannan (KGM)-soybean protein isolated (SPI) mixed gels were examined.
Optimization of formulation variables was carried out using combination of single factor method and response surface
methodology. A quadratic regression model was built using KGM to SPI ratio, total concentration, KCl concentration
and Ca(OH)2 dosage as the independent variables and gel strength as the response. Results showed that the optimum
conditions for preparing the mixed gel were determined as follows: mixed gel concentration, 4.5%; KGM/SPI ratio, 3:1;
KCl concentration, 0.13 mol/L; and Ca(OH)2 dosage, 0.15%. Under these conditions, the gel strength of SPI-KGM gels was
experimentally 2.758 N, approaching to the predicted value of 2.779 N. In addition, the texture properties of the mixed gels
were analyzed before and after the optimization, and the results indicated that the optimization was reliable.