Hydrolytic Stability at Intermediate pHs of the Common Purine Nucleotides in Food, Inosine-5'-monophosphate, Guanosine-5'-monophosphate and Adenosine-5'-monophosphate

When the purine nucleotides, inosine-5′-monophosphate (IMP), guanosine-5′-monophosphate (GMP) and adenosine-5′-monophosphate (AMP) were subjected to canning temperatures (121°C) at pHs between 3 and 8, extensive phosphate bond hydrolysis to the corresponding nucleoside occurred. The half life for hydrolysis at pH 5 was 63, 41, and 51 min for IMP, GMP, and AMP, respectively. Rates of hydrolysis were even greater at pH 3 because both hydrolysis of the phosphate bond and the glycosidic bond occurred simultaneously. An Arrhenius plot of data collected at different temperatures illustrated that the nucleotides were very stable at room temperature. Half lives for IMP, GMP, and AMP were estimated to be 36, 19, and 40 yr, respectively, at 23°C and a pH of 5.