Food Science and Nutrition Department, Faculty of Agriculture, Sohag University, Sohag 82524, Egypt.
Department of Food Engineering, Faculty of Engineering, Sakarya University, Sakarya 54187, Turkey.
Molecules. 2022 Dec 26;28(1):209. doi: 10.3390/molecules28010209.
Date kernel is a plant-derived byproduct that has the potential to be converted into a high-value-added food ingredient, such as protein concentrate, in the food industry. Ultrasound, which is an alternative method for improving the functional properties of food proteins, is an effective physical treatment for modifying protein functionality. Solubility is the main criterion that primarily affects other functional properties of protein concentrates, such as emulsification, foaming, and water and oil binding. The aim of this study is to enhance the techno-functional performance of date seed protein concentrate (DSPC) by maximizing the solubility via a high-intensity ultrasound (HIUS) treatment at a fixed frequency of 20 kHz. The effect of ultrasonic homogenization under varying amplitudes and times (amplitude of 40, 60, and 80% for 5, 10, and 15 min, respectively) on the functional properties of the DSPC was investigated by using the response surface methodology (RSM). A face-centered central composite design (FC-CCD) revealed that the optimal process conditions of HIUS were at an amplitude of 80% for 15 min. The physicochemical and functional properties of the ultrasound-applied concentrate (DSPC-US) were determined under the optimum HIUS conditions, and then these properties of DSPC-US were compared to the native DSPC. The results showed that the solubility of all DSPC samples treated by HIUS was significantly (p < 0.05) higher than that of the native DSPC. In addition, emulsion activity/stability, foaming activity/stability, and oil-binding capacity increased after HIUS homogenization treatments, whereas the water-binding capacity decreased. These changes in the techno-functional properties of the DSPC-US were explained by the modification to the physicochemical structure of the DSPC (particle size, zeta potential, SDS-PAGE, SEM, FTIR, DSC, free SH content, surface hydrophobicity, and intrinsic emission). This work revealed that HIUS could be an effective treatment for enhancing the functional properties of date seed protein concentrate.
日期核仁是一种植物衍生的副产品，有可能在食品工业中转化为高附加值的食品成分，如蛋白质浓缩物。超声是一种改善食品蛋白质功能特性的替代方法，是一种有效的物理处理方法，可用于修饰蛋白质功能。溶解度是主要影响蛋白质浓缩物其他功能特性的标准，如乳化、泡沫形成、水和油结合。本研究的目的是通过在固定频率 20 kHz 下使用高强度超声（HIUS）处理来最大限度地提高溶解度，从而提高日期种子蛋白浓缩物（DSPC）的技术功能性能。通过使用响应面法（RSM）研究了在不同振幅和时间（振幅分别为 40%、60%和 80%，时间分别为 5、10 和 15 分钟）下超声匀化对 DSPC 功能特性的影响。面心中央复合设计（FC-CCD）表明，HIUS 的最佳工艺条件为振幅 80%，时间 15 分钟。在最佳 HIUS 条件下测定了超声应用浓缩物（DSPC-US）的物理化学和功能特性，然后将其与天然 DSPC 的特性进行比较。结果表明，所有经 HIUS 处理的 DSPC 样品的溶解度均显著（p <0.05）高于天然 DSPC。此外，HIUS 匀化处理后乳液活性/稳定性、泡沫活性/稳定性和油结合能力增加，而水结合能力降低。DSPC-US 的这些技术功能特性的变化可以通过 DSPC 物理化学结构的变化来解释（粒径、Zeta 电位、SDS-PAGE、SEM、FTIR、DSC、游离 SH 含量、表面疏水性和固有发射）。这项工作表明，HIUS 可能是一种有效处理方法，可增强日期种子蛋白浓缩物的功能特性。
