Teng Yang, Ou Mingjuan, Wu Jihuan, Jiang Ting, Zheng Kaige, Guo Yuxing, Pan Daodong, Zhang Tao, Wu Zhen
College of Food Science and Engineering, Ningbo University, Ningbo 315211, China.
Ningbo Enrich Life Bio-Tec Co., Ltd., Ningbo 321004, China.
Foods. 2025 Jul 31;14(15):2702. doi: 10.3390/foods14152702.
An oat protein isolate is an ideal raw material for producing a wide range of plant-based products. However, oat protein exhibits weak functional properties, particularly in emulsification. Casein-based ingredients are commonly employed to enhance emulsifying properties as a general practice in the food industry. pH-shifting processing is a straightforward method to partially unfold protein structures. This study modified a mixture of an oat protein isolate (OPI) and casein by combining a pH adjustment (adjusting the pH of two solutions to 12, mixing them at a 3:7 ratio, and maintaining the pH at 12 for 2 h) with an atmospheric cold plasma (ACP) treatment to improve the emulsifying properties. The results demonstrated that the ACP treatment significantly enhanced the solubility of the OPI/casein mixtures, with a maximum solubility of 82.63 ± 0.33%, while the ζ-potential values were approximately -40 mV, indicating that all the samples were fairly stable. The plasma-induced increase in surface hydrophobicity supported greater protein adsorption and redistribution at the oil/water interface. After 3 min of treatment, the interfacial pressure peaked at 8.32 mN/m. Emulsions stabilized with the modified OPI/casein mixtures also exhibited a significant droplet size reduction upon extending the ACP treatment to 3 min, decreasing from 5.364 ± 0.034 μm to 3.075 ± 0.016 μm. The resulting enhanced uniformity in droplet size distribution signified the formation of a robust interfacial film. Moreover, the ACP treatment effectively enhanced the emulsifying activity of the OPI/casein mixtures, reaching (179.65 ± 1.96 m/g). These findings highlight the potential application value of OPI/casein mixtures in liquid dairy products. In addition, dairy products based on oat protein are more conducive to sustainable development than traditional dairy products.
燕麦分离蛋白是生产多种植物基产品的理想原料。然而，燕麦蛋白的功能特性较弱，尤其是在乳化方面。在食品工业中，通常采用酪蛋白基成分来增强乳化性能。pH值调节处理是一种使蛋白质结构部分展开的简单方法。本研究通过将pH调节（将两种溶液的pH值调至12，按3:7的比例混合，并在pH值为12的条件下保持2小时）与常压冷等离子体（ACP）处理相结合，对燕麦分离蛋白（OPI）和酪蛋白的混合物进行改性，以改善其乳化性能。结果表明，ACP处理显著提高了OPI/酪蛋白混合物的溶解度，最大溶解度为82.63±0.33%，而ζ电位值约为-40 mV，表明所有样品都相当稳定。等离子体诱导的表面疏水性增加有助于蛋白质在油/水界面上的更多吸附和重新分布。处理3分钟后，界面压力达到峰值8.32 mN/m。用改性OPI/酪蛋白混合物稳定的乳液在将ACP处理延长至3分钟后，液滴尺寸也显著减小，从5.364±0.034μm降至3.075±0.016μm。液滴尺寸分布均匀性的提高表明形成了坚固的界面膜。此外，ACP处理有效地提高了OPI/酪蛋白混合物的乳化活性，达到（179.65±1.96 m/g）。这些发现突出了OPI/酪蛋白混合物在液态乳制品中的潜在应用价值。此外，基于燕麦蛋白的乳制品比传统乳制品更有利于可持续发展。
