Li Tianci, Yang Chenxian, Liu Kunlun, Zhu Tingwei, Duan Xiaojie, Xu Yandong
College of Food Science and Engineering, Henan University of Technology, Zhengzhou 450001, China.
Foods. 2023 Sep 22;12(19):3523. doi: 10.3390/foods12193523.
Peanut oil body emulsion occurs during the process of aqueous enzymatic extraction (AEE). The free oil is difficult to release and extract because its structure is stable and not easily destroyed. Demulsification can release free oil in an oil body emulsion, so various fatty acids were selected for the demulsification. Changes in the amount of heptanoic acid added, solid-liquid ratio, reaction temperature, and reaction time were adopted to investigate demulsification, and the technological conditions of demulsification were optimized. While the optimal conditions were the addition of 1.26% of heptanoic acid, solid-liquid ratio of 1:3.25, reaction temperature of 72.7 °C, and reaction time of 55 min, the maximum free oil yield was (95.84 ± 0.19)%. The analysis of the fatty acid composition and physicochemical characterization of peanut oils extracted using four methods were studied during the AEE process. Compared with the amount of oil extracted via other methods, the unsaturated fatty acids of oils extracted from demulsification with heptanoic acid contained 78.81%, which was significantly higher than the other three methods. The results of physicochemical characterization indicated that the oil obtained by demulsification with heptanoic acid had a higher quality. According to the analysis of the amino acid composition, the protein obtained using AEE was similar to that of commercial peanut protein powder (CPPP). However, the essential amino acid content of proteins extracted via AEE was significantly higher than that of CPPP. The capacity of water (oil) holding, emulsifying activity, and foaming properties of protein obtained via AEE were better than those for CPPP. Overall, heptanoic acid demulsification is a potential demulsification method, thus, this work provides a new idea for the industrial application of simultaneous separation of oil and proteins via AEE.
花生油体乳液在水酶法提取（AEE）过程中产生。由于游离油的结构稳定且不易被破坏，因此难以释放和提取。破乳可以释放油体乳液中的游离油，所以选择了各种脂肪酸进行破乳。通过改变庚酸添加量、固液比、反应温度和反应时间来研究破乳情况，并优化破乳工艺条件。最佳条件为庚酸添加量1.26%、固液比1:3.25、反应温度72.7℃、反应时间55分钟，此时游离油的最大产率为（95.84±0.19）%。研究了AEE过程中用四种方法提取的花生油的脂肪酸组成分析和理化特性。与其他方法提取的油量相比，用庚酸破乳提取的油中不饱和脂肪酸含量为78.81%，显著高于其他三种方法。理化特性结果表明，用庚酸破乳得到的油质量更高。根据氨基酸组成分析，用AEE法得到的蛋白质与市售花生蛋白粉（CPPP）相似。然而，通过AEE法提取的蛋白质中必需氨基酸含量显著高于CPPP。通过AEE法得到的蛋白质的持水（油）能力、乳化活性和发泡性能均优于CPPP。总体而言，庚酸破乳是一种潜在的破乳方法，因此，这项工作为通过AEE同时分离油和蛋白质的工业应用提供了新思路。
