The chemicals responsible for imparting the sweetness, classic salt taste and bitter and
sour taste are summarized herewith. A. Sweet Taste Sweetness is one of the most important taste sensations for humans and for many animal species as well.
Substances which elicit 'sweet' sensation are primarily the organic compounds like sugars - mono and disaccharides, glucose, fructose, sucrose, various alcohols mainly ethanol, sorbitol, glycerol, non-nutritive sweeteners such as saccharine, cyclamate, aspartame.
Among them, sugars are the main sources of sweetness in foods. But not all sugars are equally sweet. Fructose gives the most intensely sweet sensation followed by sucrose, glucose, maltose, galactose and lactose respectively. Along with imparting sweetness to foods, you have learnt earlier about the other functional properties of sucrose in foods that make it useful as a bulking agent, texture modifier, mouth feel modifier and a preservative. Sucrose additionally offers an important energy source for many food fermentations.
The threshold value for sucrose is 0.342%, glucose is 1.442% and saccharine is 0.00047%. What do we mean by threshold? The concentration required for identification is known as threshold for that particular substance.