Abstract:The proteins and amino acid composition in the whole Akebia trifoliate fruits during fermentation were tracked. Combined with multiple index system，the nutritional value，flavor and medicinal value of amino acids in the fermentation process were evaluated. Then，the fermentation process was divided into stages by principal component analysis and cluster analysis，based on the content of amino acids.The results showed that with the fermentation，the proteins and amino acids showed a trend of increasing first and then tending to stabilize，which were in the range of 2.64-4.76 mg/mL and 1.36-3.76 mg/mL，respectively. The gamma -aminobutyric acid continued to increase，ranging from 64.13-162.87 μg/mL. The total contents of essential amino acids and nonessential amino acids both increased，with their ratio ranging from 0.247 to 0.426. Sulfur amino acids and cysteine were the first limiting amino acid and score of ratio coefficient of amino acids fluctuated in the range of 56.17-62.93. Digestible essential amino acids always scored more than 100% throughout fermentation，indicating that fermented A.trifoliata fruits could be ranked as'excellent'in terms of protein nutritional value. Ratios of content threshold of aspartate，glutamate and arginine were greater than 1，exerting a great impact on the flavor of the fermented products. The concentration of medicinal amino acids increased from（896.56±54.82）μg/mL to（2 890.47±138.27）μg/mL，and their proportion in total amino acids rose from 65.88% to 76.80%. The fermentation process was divided into five stages by principal component analysis and cluster analysis. The whole biological fermentation of A. trifoliata fruits would significantly improve the nutritional values of proteins and amino acids.