From the fact that high fructose corn syrup (hfcs) tastes sweeter than regular table sugar, one can conclude that

The answer to this question should be: the percentage of fructose in HFCS must be higher than that in table sugar.

The intensity of sweet sensation in the tongue will be higher if the concentration of the carbohydrate is higher. Different carbohydrates also give different basic rates. Fructose can cause more sweetness than glucose (regular table sugar). High fructose corn syrups should have about 55% concentration of fructose.

It feels feed the echo system