College of Food Science and Engineering, Tianjin University of Science & Technology, Tianjin, China.
Department of Food Science and Technology, National University of Singapore, Singapore.
J Food Sci. 2022 Sep;87(9):3737-3751. doi: 10.1111/1750-3841.16256. Epub 2022 Aug 17.
Pleurotus citrinopileatus, a nutritious and palatable edible mushroom, can be used as an appropriate material to prepare high-grade flavoring agents. Based on this, the current study aimed to investigate the feasibility of a productive protease system from Actinomucor elegans to prepare P. citrinopileatus hydrolysate (PCH). The Actinomucor elegans crude protease (AECP) was prepared from the solid-state fermentation product of P. citrinopileatus by A. elegans. AECP and four commercial proteases (alcalase, neutrase, papain, and protamex) were applied to acquire five kinds of PCHs. The physical-chemical properties of PCHs as well as its concentration and composition of nonvolatile compounds were comparatively analyzed. Sensory evaluation and electronic tongue analysis were utilized to evaluate sensory characteristics. AECP was found to be the most effective protease, with the highest hydrolysis degree (35.91%) and protein recovery (81.46%). The result of molecular weight distribution indicated that peptides below 500 Da were the main fraction of AECP hydrolysates, while AECP hydrolysates showed the highest content of monosodium glutamate-like (20.23 ± 0.16 mg/g) and flavor 5'-nucleotide (4.30 ± 0.07 mg/g) peptides. In summary, the AECP hydrolysate had superior sensory profiles compared with other hydrolysates. In addition, AECP hydrolysates exhibited favorable kokumi taste in which peptides below 500 Da showed the highest correlation with kokumi by the results of partial least-squares regression. These results indicated the feasibility of applying PCHs as flavor additives or seasoning in the food industry. AECP might be used as an alternative enzyme choice because of its low cost and high hydrolysis efficiency. PRACTICAL APPLICATION: Pleurotus citrinopileatus served as a potential raw material for natural seasonings because of its high protein content and appropriate ratio of umami amino acids to total amino acids. Enzymatic hydrolysis was an efficient approach to improve the flavor of P. citrinopileatus, where the choice of enzyme was one of the most critical factors. The research indicated that P. citrinopileatus hydrolysate prepared by A. elegans crude protease (AECP) exhibited an acceptable flavor, which provided theoretical support for the high-value utilization of P. citrinopileatus as food seasoning. AECP might be applied as an alternative enzyme resource because of its low cost and high hydrolysis efficiency.
金顶侧耳，一种营养丰富、味道鲜美的食用菌，可用作制备高档调味剂的合适材料。基于此，本研究旨在探讨利用秀丽放射毛霉（Actinomucor elegans）生产性蛋白酶系统制备金顶侧耳水解物（PCH）的可行性。金顶侧耳固态发酵产物经秀丽放射毛霉发酵后制备得到秀丽放射毛霉粗蛋白酶（AECP）。将 AECP 与四种商业蛋白酶（碱性蛋白酶、中性蛋白酶、木瓜蛋白酶和复合蛋白酶）分别用于制备五种 PCH。比较分析了 PCH 的物理化学性质及其非挥发性化合物的浓度和组成。利用感官评价和电子舌分析来评价感官特性。结果表明，AECP 是最有效的蛋白酶，水解度（35.91%）和蛋白质回收率（81.46%）最高。分子量分布结果表明，500 Da 以下的肽是 AECP 水解物的主要组成部分，而 AECP 水解物具有最高的谷氨酸单钠盐（20.23±0.16 mg/g）和风味 5'-核苷酸（4.30±0.07 mg/g）肽含量。综上所述，AECP 水解物的感官特性优于其他水解物。此外，通过偏最小二乘回归分析结果表明，500 Da 以下的肽与 kokumi 味相关性最高，AECP 水解物具有良好的 kokumi 味。这些结果表明，PCH 作为食品工业中的风味添加剂或调味料具有可行性。由于 AECP 成本低、水解效率高，因此可能被用作替代酶选择。
金顶侧耳因其高蛋白含量和鲜味氨基酸与总氨基酸的适当比例，可用作天然调味料的潜在原料。酶解是提高金顶侧耳风味的有效方法，其中酶的选择是最关键的因素之一。研究表明，由秀丽放射毛霉粗蛋白酶（AECP）制备的金顶侧耳水解物（PCH）具有可接受的风味，为金顶侧耳作为食品调味料的高值利用提供了理论支持。由于 AECP 成本低、水解效率高，因此可能被用作替代酶资源。
