Nutritional characteristics of proteins from the volva and pileus in cultivated mushroom Dictyophora rubrovolvata.

Dictyophora rubrovolvata is one of the commercially important mushroom species in China. However, its volva and pileus account for about 65% of the whole mushroom (by fresh weight), and most of them are dumped without utilization. To effectively utilize the waste, the present study determined their proximate composition and investigated the nutritional characteristics of their proteins via the analysis of amino acid composition and protein fractionation. The results showed that the volva and pileus were rich in protein with 26.74% and 15.55% (dry basis), respectively. Predicted protein efficiency ratio values of proteins of the volva and pileus were 2.8 and 2.2, and the amino acid scores were 96 and 85.The albumin was the highest fraction both in the volva and pileus, accounting for 69.52% and 27.91% of the crude protein. The protein quality of the volva was therefore higher than that of the pileus. The volva might be developed as resource of high-quality vegetable-base protein.