Table 3 summarises 29 kinds of amino acids and their derivatives (NH3 excluded), detected in fresh and different dried P. eryngii.Contents of total free amino acids (FAA) were significantly different
among these samples (p < 0.05), in the range from 4.55 to 19.26 mg/g. The maximal total concentration was found in HA treated products. Unlike the results of 50-nucleotides, content of total FAA in FZ mushroom was lower than that of others, except for the sample treated with MW. Eight essential amino acids (EAA) for humans were detected in these samples, and the total contents of EAA ranged from 0.85 mg/g to 3.88 mg/g, with the highest concentration in HA treated samples and lowest in MW treated samples. His and Arg, supplements from foods to satisfy a human’s requirement, were detected in these samples. Kim et al. (2009) reported identical kinds of FAA, with significantly higher contents of total FAA and EAA in FZ P. eryngii, than those in this study (p < 0.05). The differences of the concentrations of FAA and EAA were probably caused by the different extracting methods, especially with high contents of MSG-like components (8.63 mg/g).