Abstract: The taste components in yeast extract were analyzed by an automatic amino acid analyzer and high performance liquid chromatography (HPLC). Then the contribution of each taste component to the taste of yeast extract was evaluated by calculating the taste activity value (TAV), and the synergistic interactions between umami components were demonstrated through the calculated equivalent umami concentrations (EUC). Furthermore, the main taste components were determined by omission and addition test. Finally, yeast extract, salt and sucrose were used as raw materials to develop an umami-enhancing and deodorizing seasoning, and the optimal combination of the three ingredients was determined by single factor experiments and orthogonal array design. The changes in the taste of steamed silver carp fillets before and after the seasoning treatment were analyzed by electronic tongue. Results showed that sodium glutamate, alanine, 5’-GMP, 5’-IMP, sodium aspartate, arginine, tyrosine and 5’-AMP contributed the most to the taste of yeast extract. The EUC was calculated to be 184.48 g/g, indicating a strong synergistic interaction between umami amino acids (sodium glutamate and aspartate) and umami nucleotides (5’-GMP, 5’-IMP and 5’-AMP). The optimum formulation of seasoning for enhancing umami and reducing fishy odor consisted of 1% yeast extract, 1.5% salt, and 0.5% sucrose. After being pickled with the seasoning, the umami taste of silver carp fillets was obviously improved and the fishy odor was mitigated.

Key words: yeast extract; silver carp; analysis of taste components; synergistic effects; umami-enhancing and deodorizing seasoning