Abstract:In order to test the differences in umami compounds during the Coilia nasua migration process,the cooked meat was analyzed by spectrophotometry,flame atomic absorption spectroscopy and high performance liquid chromatography. The changes of composition of Coilia nasua umami compounds from January to December were compared, and the taste activity value (TAV) and equivalent umami concentration (EUC) of each umami compound were calculated in order to study the relation between concentrations of umami substances and umami intensity. Results showed that:the change rule of the contents of most umami compounds was relatively uniform, and the trend of increasing from January to March and then decreasing dramatically, decreasing gently from April or May, and increasing again from October was observed throughout the year except that the concentrations of most inorganic ions decreased from January to March due to removal of salts; the change of MSG equivalent of Coilia nasua meat was similar to that of composition of umami compounds,peaked in March (Coilia nasua is most delicious in March.).Integral analysis of its physical and chemical indicators and its growth rule indicated the gonad of the Coilia nasua started developing to mature from March, consuming of a lot of nutrient, which results in umami compounds decrease dramatically; the Coilia nasua ate no food during the migration and consumed a lot of energy,caused umami compounds to be further consumed; after the Coilia nasua reached the reproductive field in October, they begin to eat, and prepare for the next migration, which prompted the umami compounds in the Coilia nasua to start to pick up.