冷冻魔芋复合凝胶保水性和质构特性的调控

本研究将瓜尔豆胶、大豆油、乳化剂依次加入到魔芋凝胶中,以探究其对冷冻魔芋凝胶保水性和质构特性的影响。首先添加瓜尔豆胶到魔芋凝胶中,相比于控制组(纯魔芋凝胶),冷冻后的魔芋/瓜尔豆胶复合凝胶的保水性能提升,其冷冻析水率最多减小了3.63%,持水率最大升高了4.68%,硬度最多增大了930.74 g。为了进一步提高冷冻复合凝胶的保水性,将大豆油和乳化剂添加入魔芋/瓜尔豆胶复合凝胶中。添加大豆油可以增大魔芋/瓜尔豆胶凝胶的保水性,但复合凝胶硬度有所降低。在魔芋/瓜尔豆胶/大豆油复合凝胶中添加5种不同的乳化剂进行对比,发现单甘油脂肪酸酯对提高冷冻凝胶的保水性的效果最好。当瓜尔豆胶、大豆油和单甘油脂肪酸酯在复合凝胶中的比例分别为0.10%、5%和0.10%时,对比控制组,冷冻复合凝胶的析水率由25.37%降低到10.19%,持水率由62.55%升高至82.83%,但凝胶硬度降低。瓜尔豆胶、大豆油和单甘油脂肪酸酯的复合添加可以有效改善魔芋凝胶在冷冻后的保水能力,并改变了凝胶的质构特性。本研究为调控冷冻魔芋复合凝胶的性能提供了数据支撑,也为冷冻魔芋复合凝胶产品的生产提供了理论参考。

Regulation of Water Retention Capacity and Texture Property of Frozen Composite Gel

Guar gum (GG), soybean oil (SO), and emulsifier were successively added to konjac glucomannan (KGM)gel to explore their effects on the water retention capacity (WRC) and texture property of frozen KGM gel. Firstly, GG was added to KGM gel. Compared with that of the control (pure KGM gel), the WRC of frozen composite KGM/GG gel increased, with a maximum of 3.63% decrease in the syneresis rate (SR) and a maximum of4.68% increase in the water holding capacity (WHC).On the other hand, the hardness of composite gel had a maximum increase of 930.74 g. In order to further improve the WRC of the frozen composite gel, SO and emulsifier were added to the composite KGM/GG gel. It was found that the addition of SO increased the WRC but decreased the hardness of the frozen composite KGM/GG gel. Comparing the five emulsifiers used, glyceryl monostearate (GM) improved the WRC of frozen composite KGM/GG/SO gel the most. Comparedwith that of the control, the SR of the frozen composite gel dropped from 25.37% to 10.19% and its WHC increased from 62.55% to 82.83% when the concentrations of GG, SO and GM in the composite gel were 0.10%, 5%, and 0.10%, respectively. However, the hardness of the composite gel decreased. These results indicate that the combined addition of guar gum, soybean oil, and glyceryl monostearate effectively improves the WRC and changes the texture property of the KGM gel after freezing. This study provides data support for regulating the properties of frozen KGM composite gel and a theoretical reference for the fabrication of frozen composite KGM gel products.