Multidimensional Quality Assessment of Lyophyllum Decastes Mushroom Varieties: Nutritional Components, Protein Characteristics and Umami Profiling

Abstract

This study comprehensively assessed the nutritional and umami traits of twelve Lyophyllum decastes varieties to identify superior strains for functional foods. Macronutrients, amino acid profiles, protein quality indices (amino acid score, AAS; score of ratio coefficient, SRC; protein digestibility-corrected amino acid score, PDCAAS), umami compounds, and equivalent umami concentration (EUC) were analyzed. A novel Content-Digestibility-Balance 3D framework, combined with cluster analysis and PCA-membership function, enabled integrated quality evaluation. Results showed significant varietal differences: crude protein (20.25–27.88%), polysaccharides (2.86–6.94%), and EUC (39.77–211.48 g MSG/100g). Essential amino acid ratios (34.78–41.69%) aligned with FAO/WHO standards, with methionine+cysteine as the limiting amino acid. Protein quality indices (AAS, SRC, PDCAAS) demonstrated superior amino acid balance compared to other fungi and cereals. The L6 variety excelled, exhibiting the highest protein (27.88%), EUC (211.48 g MSG/100g), and optimal protein indices. Multivariate analysis identified crude protein, sweet amino acids, and EUC as key discriminators (PC1: 41.97%), ranking L6, L7, and L5 highest. Negative fat-polysaccharide correlations (r = -0.709) revealed metabolic trade-offs, while clustering classified samples into three quality tiers. This study provides a systematic, data-driven strategy for breeders and producers to optimize L. decastes cultivation, enhancing both nutritional value and consumer appeal in mushroom-based products.

Keywords: Lyophyllum decastes, Nutrition, amino acid assessment, taste quality, membership function