Most protein concentrates used by the food industry are derived from soybean or wheat, but a pseudocereal like quinoa is gaining interest worldwide. The aim of this study is the characterization of the emulsification properties of two quinoa protein concentrates obtained through alkaline extraction (pH 9 (Q9) and 11 (Q11)), followed by precipitation at an acidic pH value. Interfacial rheological measurements point out that Q11 form stronger protein films adsorbed on the interface, which finally results in emulsions with smaller droplet sizes. However, Q9 shows greater interfacial activity due to its more compact structure which results in a lower interfacial tension. An increase in the quinoa content in the emulsion formulation is paired with a reduction in the droplet size diameter as well as a greater stability during quiescent storage. These results prove the feasibility of using a quinoa concentrate as an ingredient in commercial food emulsions.

中文翻译：

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藜麦浓缩蛋白的界面和乳化特性

食品工业使用的大多数蛋白质浓缩物都来自大豆或小麦，但是像藜麦这样的假谷物正在全球范围内引起人们的兴趣。这项研究的目的是表征通过碱萃取（pH 9（Q9）和11（Q11）），然后在酸性pH值下沉淀获得的两种藜麦浓缩蛋白的乳化特性。界面流变学测量结果表明，Q11形成更牢固的蛋白质膜吸附在界面上，最终导致乳液的液滴尺寸更小。但是，由于Q9的结构更为紧凑，因此界面活性更高，从而降低了界面张力。乳液配方中藜麦含量的增加与液滴尺寸直径的减小以及静态存储过程中的更大稳定性相辅相成。