Production of guanylic acid by cooking of tomato

Abstract

Guanylic acidenhances the umami-taste of glutamic acid. We analyzedthe content of guanylic acidin tomato fruits of 11 cultivars before andafter cooking. The contents were significantly higher in heatedrather than nonheatedfruit among all cultivars. To investigate the effect of heating on guanylic acidaccumulation, we analyzedthe content of guanylic acid and its degradation product, guanosine, in tomato fruits heated at temperatures between 25°C and 100°C. Basedon the content of the two compounds, we speculate that the difference in quantity between the production and degradation of guanylic acid was the highest at 50-60°C, and that the maximum accumulation of guanylic acidoccurredat 50-60°C.