Pumpkins undergo a number of changes in the chemicals in the fruit during growth, including an increase in soluble sugars and a shift in other chemicals, which can give different fruits different flavors, not only pumpkins but other fruits as well.

The fist-sized tender pumpkin contains a small amount of bittersweet, slightly bitter flavor, which is normal, but not poisonous, just because such a pumpkin does not have a real pumpkin kind of flavor, so try not to eat too tender.