Microalgae are considered to be a promising alternative protein source after extraction and fractionation. Studies have shown that the insoluble protein fraction possesses interfacial activity and is able to stabilize oil-in-water emulsions after acid hydrolysis. The current work studied the surface pressure and foaming properties of the insoluble microalgae protein fraction obtained from Chlorella protothecoides and two of their hydrolysates. Results showed that the surface pressure of the three used protein fractions increased with increasing protein concentration. Moreover, surface pressure of the insoluble microalgae protein increased after hydrolysis at 65 °C (Hydrolysates 65) or 85 °C (Hydrolysates 85) suggesting an increased foaming capacity of the insoluble microalgae protein fraction after hydrolysis. Hydrolysates 85 had the highest foam capacity, and foams remained stable with a half-life time of over 5 h. Overall, hydrolysis of the insoluble microalgae protein fraction with 0.5 M HCl at 85 °C for 4 h resulted in generation of protein fragments that appear to be very suitable to stabilize air-water interfaces in foam-based foods.

中文翻译：

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原生小球藻的酸水解不溶微藻蛋白起泡

在提取和分级分离之后，微藻被认为是有前途的替代蛋白质来源。研究表明，不溶的蛋白质级分具有界面活性，能够在酸水解后稳定水包油型乳剂。当前的工作研究了从原绿小球藻获得的不溶性微藻蛋白馏分的表面压力和起泡特性。和他们的两个水解产物。结果表明，三个蛋白质级分的表面压力随蛋白质浓度的增加而增加。而且，在65℃（水解物65）或85℃（水解物85）水解后，不溶性微藻蛋白的表面压力增加，表明在水解后不溶性微藻蛋白级分的起泡沫能力增加。水解物85的泡沫容量最高，泡沫保持稳定，半衰期超过5小时。总体而言，不溶性微藻蛋白级分在0.5°C的盐酸中于85°C水解4 h，导致生成的蛋白片段似乎非常适合稳定泡沫食品中的空气-水界面。