|MadSci Network: Biochemistry|
The consensus is that it is unlikely you could ever accumulate enough ATP on your tongue to taste it before it was converted to ADP and phosphate (or other products), however I did find some interesting information about some of the byproducts of ATP and their flavors:
From the book: Food Storage Stability By Irwin A. Taub, R. Paul Singh, they say:
"AMP tends to accumulate in postmortem molluscs (eg clams) and crustacea (eg crab) where it plays and important role in the delicious umam taste of the meat. In most mycosystems, however, the accumulation of IMP from ATP is rapid, and transient accumulation of inosine monophosphate, a flavor enhancer, contributes to the good taste of fresh meat and fish. The subsequent accumulation of inosine and/or hypoxanthine normally occurs at a relatively slower rate. Some species or fish tend to accumulate mainly inosine, others accumulate mainly hypoxanthine, and some accumulate both inosine and hypoxanthine. Hypoxanthine has a bitter flavor and has been reported to cause off-flavor in several meat products including poultry, irradiated beef, and fish."
This may not answer your question directly, but hopefully it is interesting.
[Moderator's Note: We have a few answers in our archives that discuss the very short half-life of ATP molecules. For example, take a look at answer 1121207318.Bc. -- Steve Mack]
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