To investigate the effect of welsh onion on taste components and sensory characteristics in porcine bone soup, the stewing condition was as follows: the material-liquid ratio (m/V) was 1:1, the stewing time was 5.0 h, and the ratio of welsh onion was 2.5%. Then, the content of taste components was measured. The content of free amino acids in porcine bone soup with welsh onion (PWS) was higher than the sum of welsh onion soup (WS) and porcine bone soup (PS); particularly, the umami amino acids increased by 35.73% compared with PS. Significant increases in four organic acids (lactic acid, pyroglutamic acid, citric acid and ascorbic acid), two 5'-nucleotides (5'-AMP and 5'-GMP) and three mineral elements (K, Ca and Mg) were observed in PWS. Compared with PS, the equivalent umami concentration (EUC) value was increased from 79.09 to 106.47 mg MSG/100 g in PWS, which was due to the high content of umami amino acids and the synergistic effect with 5'-nucleotides. The results of the sensory analysis indicated a certain enhancement of umami taste in PWS, and the sweet and salty tastes were also increased with the addition of welsh onion. The correlation analysis was consistent with the variation of the components tested above.
Keywords: porcine bone soup; sensory characteristics; taste components; umami; welsh onion.