How does sugar affect the taste of a bitter, salty, or sour substance?
Sweetness lowers the intensity of a bitter, salty, or sour taste quality. This phenomenon partially explains why a coffee drinker adds sugar to a bitter brew, why a cook adds a pinch of sugar to an oversalted dish, and why a lemonade maker uses sugar to counteract the acidity of the lemon juice. Interestingly, the reverse is true too. A bitter, salty, or sour substance lowers the intensity of sugar. That's why it's difficult for our taste buds to detect how much salt and sugar some processed foods contain.
Try this sugar-salt taste experiment
See how salt and sugar significantly affect each other in your taste perception. Half fill three standard-sized glasses with room-temperature water. Label them A,B, and C. Stir 1/2 teaspoon of salt into glasses A and B. Stir 1 teaspoon of sugar into glasses B ad C. Cross-taste A and B. Does A taste saltier than B even though both contain the identical quantity of salt? Now cross-taste B and C for sweetness. Does C taste sweeter than B even though both contain the same amount of sugar?
** Asian Recipes