黄原胶对面筋蛋白流变特性的影响

冷冻面制品在冻藏过程中由于冰晶迁移及重结晶导致面筋蛋白网络结构弱化，从而降低其品质。黄原胶作为一种优良的面团改良剂，其在冷冻面团中的应用受到越来越多的关注。本论文主要研究了黄原胶对面筋蛋白持水性、溶解度、流变特性及超微网络结构的影响。结果表明：黄原胶的添加能显著提高面筋蛋白持水性，当使用浓度为0.25%（m/m）黄原胶溶液与面筋蛋白进行混合时，面筋蛋白的持水性比原来提高9.1%，达到131.8%；面筋蛋白溶解度随黄原胶添加量的增大先升高后降低，当黄原胶/面筋蛋白比例为0.075%时，面筋蛋白溶解度为4.08 mg/mL，比原面筋蛋白增加了0.77 mg/mL；添加一定量的黄原胶，导致面筋蛋白弹性减弱，而黏性增强（储能模量G'下降，损耗模量G''和损耗角正切值tan δ升高）；面筋蛋白网络结构，也随黄原胶的添加而更加的均匀，当黄原胶/面筋蛋白比例为0.375%时，面筋蛋白复配体系孔径大小由近100 μm减至20 μm左右。
The gluten network structure of wheat flour-based products is weakened during cold storage owing to ice crystal migration and recrystallization, resulting in reduced quality. Xanthan gum is an excellent food additive, and its application in frozen dough has attracted increasing attention. The effects of xanthan gum on the rheological properties, water-holding capacity, solu bility, and the ultramicro network structure of gluten proteins were studied. The results showed that the water-holding capacity significantly increased when xanthan gum was added. When 0.25% (m/m) xanthan solution was mixed with gluten, the water-holding capacity reached 131.8%, which was 9.1% higher than that of the original gluten proteins. The solubility of gluten declined after the initial increase with the increasing amount of added xanthan gum. When the ratio of xanthan/gluten was 0.075%, the solubility of gluten was 4.08 mg/mL, 0.77 mg/mL higher than that of the original gluten. The addition of a certain amount of xanthan gum led to a decreased gluten elasticity and an increased viscosity (decreased storage modulus G', increased loss modulus G'', and loss tangent tan δ). The gluten network structure became more uniform with the addition of xanthan gum; when the xanthan/gluten ratio was 0.375%, the pore size of the gluten/xanthan complex system decreased from 100 μm to approximately 20 μm.