Abstract:To investigate the differences in amino acid content， composition characteristics， and nutritional value among different chestnut varieties， liquid chromatography-tandem mass spectrometry was used to determine the contents of 20 amino acids in 10 chestnut varieties from the Shandong region （3 113， Jinping-Culai Mountain， Shifeng， Huangpeng， Jinping， Yanshanhong， Mengzao， Yichuanhong， Yifeng， and Likang）. The contents of total amino acids， essential amino acids， flavor amino acids， and special functional amino acids were calculated. Combined with the amino acid pattern recommended by the World Health Organization/Food and Agriculture Organization， nutritional evaluation was conducted using amino acid ratios， amino acid ratio coefficients， and ratio coefficient scores. Principal component analysis and cluster analysis were applied for comprehensive ranking and classification. The results showed that the total amino acid contents of the 10 chestnut varieties ranged from 3 460.78 μg/g to 6 757.29 μg/g， with significant differences among varieties. Mengzao chestnut had the highest total amino acid content （6 757.29 μg/g）， while Likang chestnut had the highest essential amino acid content （1 573.71 μg/g） and amino acid ratio coefficient score （70.89）. Met+Cys was the first limiting amino acid in all chestnut varieties. Flavor analysis indicated that umami amino acids and sweet amino acids were the main flavor components， and Huangpeng chestnut had the highest proportion of umami amino acids （32.09%）. Likang chestnut had the highest contents of branched-chain amino acids and aromatic amino acids， at 716.39 μg/g and 389.21 μg/g， respectively. According to the comprehensive scores of principal component analysis， the top five varieties were Mengzao， Likang， Huangpeng， Jinping， and Yifeng chestnuts. Overall， chestnuts had a comprehensive amino acid composition， and Likang and Mengzao chestnuts were the varieties with the best overall performance.