Modified soybean protein liquid, preparation method thereof and coating preservative for frozen ball products

The invention provides a preparation method of a modified soybean protein solution, which comprises the following steps: A) dissolving a soybean protein dissolving solution, sugar and hydroxypropyl methyl cellulose, homogenizing, and adjusting the pH value to obtain a soybean protein reaction solution; and B) carrying out heat treatment on the soybean protein reaction solution, and stirring to obtain the modified soybean protein solution. The modified soybean protein liquid provided by the invention has better water-blocking and oxygen-isolating effects, and can be cooperated with other components to finally prepare the coating preservative, so that the water loss can be reduced, and the color and luster of the product can be kept well. 本发明提供了一种改性大豆蛋白液的制备方法，包括如下步骤：A)大豆蛋白溶解液、糖和羟丙基甲基纤维素溶解，均质，调节pH值，得到大豆蛋白反应溶液；B)将所述大豆蛋白反应溶液热处理，搅拌得到改性大豆蛋白液。本发明提供的改性大豆蛋白液在阻水隔氧方面效果更优，与其余组分协同配合最终制备得到的涂膜保鲜剂可以降低水分损耗、保持产品色泽效果好。