Yang Xufeng, Zhou Luyao, Wu Yingying, Ding Xiuzhen, Wang Wentao, Zhang Dajian, Zhao Luping
College of Food Science and Engineering, Shandong Agricultural University, Tai'an 271018, China.
Engineering and Technology Center for Grain Processing of Shandong Province, Tai'an 271018, China.
Foods. 2023 Aug 3;12(15):2942. doi: 10.3390/foods12152942.
Soybean oil body (SOB) emulsions were prepared using OBs extracted at pH 11.0 and pH 7.0. The pH 11.0-SOB comprised oleosins, whereas pH 7.0-SOB comprised extrinsic proteins and oleosins. All SOB emulsions were heated at 60-100 °C for 15 min. Heating may lead to the release of extrinsic proteins from the surface of pH 7.0-SOB due to heat-induced denaturation. The total proportion of α-helix and β-sheets gradually decreased from 77 (unheated) to 36.2% (100 °C). During stomach digestion, the extrinsic protein hydrolysis of heated pH 7.0-SOB emulsions was fast between 60 and 80 °C, and it then slowed between 90 and 100 °C; heating inhibited the oleosin hydrolysis of pH 7.0- and 11.0-SOBs. Heat treatment promoted aggregation and coalescence, and it resulted in increased particle sizes for all emulsions. Larger aggregates were found in heated pH 7.0-SOB emulsions, and larger oil droplets were found in heated pH 11.0-SOB emulsions. After intestinal digestion, the droplets of all SOB emulsions gradually dispersed, and particle sizes decreased. Different heating temperatures had lesser effects on particle sizes and microstructures. Lipolysis was affected by the extraction pH and heating. For pH 11.0-SOB emulsions, the FFA release tendency was greatly affected by the heating temperature, and heating to 80 °C resulted in the highest FFA release (74%). However, all pH 7.0-SOB emulsions had similar total FFA releases. In addition, the droplet charges of heated pH 7.0-SOB emulsions were lower than those of unheated pH 7.0-SOB emulsions in both the intestine and stomach phases; however, the charge changes in different pH 11.0-SOB emulsions showed the opposite tendency. This study will offer guidance regarding the application of SOB emulsions in food.
使用在pH 11.0和pH 7.0条件下提取的油体（OB）制备大豆油体（SOB）乳液。pH 11.0的SOB包含油质蛋白，而pH 7.0的SOB包含外在蛋白和油质蛋白。所有SOB乳液在60 - 100°C加热15分钟。加热可能会由于热诱导变性导致外在蛋白从pH 7.0的SOB表面释放。α - 螺旋和β - 折叠的总比例从77%（未加热）逐渐降至36.2%（100°C）。在胃部消化过程中，加热的pH 7.0的SOB乳液的外在蛋白水解在60至80°C之间较快，然后在90至100°C之间减缓；加热抑制了pH 7.0和11.0的SOB的油质蛋白水解。热处理促进了聚集和聚结，导致所有乳液的粒径增大。在加热的pH 7.0的SOB乳液中发现较大的聚集体，在加热的pH 11.0的SOB乳液中发现较大的油滴。肠道消化后，所有SOB乳液的液滴逐渐分散，粒径减小。不同的加热温度对粒径和微观结构的影响较小。脂解受提取pH和加热的影响。对于pH 11.0的SOB乳液，游离脂肪酸（FFA）释放趋势受加热温度影响很大，加热至80°C导致最高的FFA释放（74%）。然而，所有pH 7.0的SOB乳液的总FFA释放相似。此外，在肠道和胃部阶段，加热的pH 7.0的SOB乳液的液滴电荷均低于未加热的pH 7.0的SOB乳液；然而，不同pH 11.0的SOB乳液中的电荷变化呈现相反趋势。本研究将为SOB乳液在食品中的应用提供指导。
