绿豆淀粉魔芋凝胶基体的制备及性能表征

Preparation and Characterization of Konjac Gel with Added Mung Bean Starch

摘要:

为改善纯魔芋凝胶品质及扩大魔芋凝胶在素食行业中的快速应用，该研究以魔芋粉、绿豆淀粉为研究对象，以硬度和持水力为评价指标，通过单因素和正交试验得到制备绿豆淀粉魔芋凝胶基体的最优工艺。同时利用差式扫描量热仪（Differential scanning calorimeter，DSC）、傅立叶红外光谱（Fourier-transform infrared spectroscopy，FT-IR）、扫描电镜（Scanning electron microscope，SEM）和X-射线衍射（X-ray diffraction，XRD）等手段对添加绿豆淀粉前后的魔芋凝胶性能进行对比分析。结果表明，制备绿豆淀粉魔芋凝胶基体最优工艺参数为淀粉量3.00 g、碱含量7.00%、冷冻时间1.50 h、溶胀时间1.50 h、柠檬酸浓度0.50% m/V。此条件下制备的绿豆淀粉魔芋凝胶基体硬度为1782.61 g，持水力为92.63%，较纯魔芋凝胶相比分别提高了54.30%、2.41%，具有更好的凝胶状态和持水效果。性能表征分析进一步证明了绿豆淀粉与魔芋粉具有相容性，绿豆淀粉魔芋混合体系相互作用加强，形成了网络状的空间结构，具有更好的质构特性。

Abstract:

Konjac flour and mung bean starch combinations were evaluated to improve the quality of pure konjac gel and expand the rapid application of konjac gel in the food industry. Hardness and water holding capacity were adopted as evaluation indicators, and the optimal process for preparing the mung bean starch-konjac gel matrix was obtained through single-factor and orthogonal experiments. In addition, the properties of konjac gel before and after addition of mung bean starch were analyzed and compared by means of differential scanning calorimetry, Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. The results showed that the optimal process parameters for preparing mung bean starch-konjac gel matrix were a starch content of 3.00 g, an alkali content of 7.00%, a freezing and swelling time of 1.50 h each, and a citric acid concentration of 0.50% m/V. The hardness of the mung bean starch-konjac gel matrix prepared under this condition was 1782.61 g, and the water holding capacity was 92.63%, which were 54.30% and 2.41% higher, respectively, than those of pure konjac gel; hence, the combination demonstrated better gelling and water holding performances. The performance characterization analysis further showed that mung bean starch and konjac flour are compatible, and the interactions between them in the matrix system are strong, forming a networked spatial structure and giving improved texture characteristics.