Flavor compounds in straw mushrooms Volvariella volvacea harvested at different stages of maturity

Straw mushrooms were harvested at different stages of maturity. The volatile flavor compounds found in straw mushrooms were limonene, octa-1,5-dien-3-ol, 3-octanol, 1-octen-3-ol, 1-octanol, and 2-octen-1-ol, in which the major compound was 1-octen-3-ol, accounting for 71.6-83.1% of the total volatiles. More mature straw mushrooms possessed the most aroma. Straw mushrooms were high in trehalose (349.0-457.6 mg/g dry weight) and low in mannitol (0-25.5 mg/g). During the development of fruiting bodies, the contents of total free amino acids and monosodium glutamate components, including aspartic and glutamic acids, increased remarkably from 36.11 and 11.20 mg/g dry weight at stage 1 to 60.18 and 26.21 mg/g at stage 5, respectively, in which glutamic acid was the most significant, increasing from 7.72 at stage 1 to 21.00 mg/g dry weight at stage 5. The content of total 5'-nucleotides and flavor 5'-nucleotides (5'-IMP and 5'-GMP) accumulated steadily with maturation. In this study, more flavor compounds, including both aroma and taste compounds, occurred in straw mushrooms harvested at stages 4 and 5 (stipe elongated and cap opened).