Abstract:  13 kinds of amino acid were calculated by CNDO method (Complete Neglect of Differential Overlap method), and relationship analysis was done between molecular structure of amino acid and sweet taste. It was found that sweet taste was significantly related to α-H, carbonyl of amino acid and one of amino-H (P<0. 01). It was supposed that the sweet taste response was intermolecular hydrogen bonding between amino acid and taste bud receptor site. The sweet unit of amino acid was α-H, carbonyl-O and one hydrogen atom of NH3+ group. The taste bud receptor site was AH (hydrogen provider) and B (hydrogen acceptor). The strength of the hydrogen bond between H of NH3+ group and the 3rd receptor site of taste bud resolved in the intensity of sweetness.

Key words: Amino acid Quantum chemical conference Sweet taste