Taste modification of amino acids and protein hydrolysate by α-cyclodextrin

The objective of this work was to characterize the formation of amino acid inclusion complexes with α-cyclodextrin (α-CD) and evaluate the influence of added α-CD on the taste perception of amino acids and hydrolyzed soy protein at pH 4.5. The formation of the inclusion complexes of phenylalanine, tryptophane, tyrosine, isoleucine, proline and histidine with α-CD were detected by nuclear magnetic resonance techniques (ROESY and DOSY) and the sensory characteristics of soy hydrolysates were judged by a panel of trained tasters. It was concluded that these amino acids form inclusion complexes with α-CD and the order of affinity for the α-CD cavity is phenylalanine ≈ tryptophane > proline > isoleucine ≈ tyrosine ≈ histidine. α-CD alters the bitter taste perception of the amino acids and reduces the bitter taste from hydrolyzed soy protein. These results indicate a potential use of α-CD for debittering protein hydrolysates in acidic beverages.