关键词: 食用菌, 替代蛋白, 氨基酸分析, 体外消化, 理化特性, 结构分析

Abstract:

【Objective】 From the perspectives of nutrition and processing, the amino acid composition, physicochemical properties, and structural characteristics of common edible fungal proteins were analyzed to elucidate the nutritional benefits of proteins derived from fungi, and to explore their prospective applications within the realm of food processing.【Method】 From the vantage points of raw material accessibility and economic advantages, eight species of edible fungi were chosen as subjects for this study: Lentinula edodes, Agaricus bisporus, Hypsizigus marmoreus (white cultivar), Pleurotus ostreatus, Hypsizygus marmoreus (brown cultivar), Agrocybe aegerita, Flammulina filiformis, and Pleurotus eryngii. To evaluate the disparities in amino acid composition and digestibility of their proteins, by utilizing metrics such as ratio of amino acid and amino acid ratio coefficient, the nutritional value and potential benefits of these fungal proteins as substitutes for conventional proteins were assessed by comparing them with whole egg protein, wheat protein, and soybean protein. The physicochemical properties of various edible fungal proteins were analyzed, including solubility, water-holding property, oil-holding property, emulsifying property, and foaming property. The structural characteristics were analyzed by Fourier-transform infrared spectroscopy and scanning electron microscopy. The correlation between physicochemical properties and structural characteristics were established, and the potential applications of edible fungal proteins within the food industry were assessed.【Result】 The EAA/TAA ratios of all eight edible fungal proteins were approximately 40%, while the EAA/NEAA ratios exceeded 60%, aligning with the ideal protein model. The amino acid profile of L. edodes protein exhibited the greatest similarity to the amino acid pattern spectrum and the reference protein's amino acid composition, boasting an essential amino acid index of 66.31. Upon adjusting the amino acid score to account for digestibility, L. edodes protein continued to hold the highest overall score, establishing it as a high-quality protein source. Furthermore, the essential amino acids of A. aegerita protein constituted 47.12% of its total amino acid profile, a figure comparable to that of whey protein, thereby rendering it an exceptional supplementary source of these vital essential amino acids. The digestibility of the protein from H. marmoreus (white cultivar) was 89.59%, and as a protein that is rapidly digestible, it would be suitable for facilitating swift physical recovery post-exercise. The physicochemical properties of the eight edible fungal proteins also exhibited considerable differences. Both H. marmoreus (white cultivar) and H. marmoreus (brown cultivar) displayed favorable water-holding, oil-holding and emulsifying properties, suggesting extensive potential applications within the realm of food processing.【Conclusion】 Utilizing the nutritional evaluation system for edible fungi, the amino acid profile of L. edodes protein has been determined to possess the highest overall rating, thus establishing L. edodes protein as a viable standalone protein supplement. The proteins of P. ostreatus, P. eryngii, H. marmoreus (white cultivar) and H. marmoreus (brown cultivar) possessed processing advantages and structural similarities in various aspects, rendering them suitable for application in the production and processing of meat products, flour-based products, and baked goods, thereby optimizing the utilization of their nutritional and processing benefits.

Key words: edible fungi, alternative proteins, amino acid analysis, in vitro digestion, physicochemical properties, structural analysis