Sweetness

The most obvious sensory property of sugars such as glucose fructose and sucrose is their sweetness, which varies depending on the specific sugar. There is no objective test for measuring the degree of sweetness.

Lactose or milk sugar is the least sweet, whereas all investigators agree that fructose is the most sweet sugar. Maltose is less sweet than glucose.

Sweetness helps mask or balance both sourness and bitterness from other ingredients. It has enhancing effect on perception of food aromas, perhaps by signaling the brain that the food is a good energy source and therefore deserves special attention.

Sweet-tasting compounds are characterized by a glycopene, which is able to bind to G-protein coupled trans-membrane receptors on the tongue.

According to the AH-B theory of sweetness this glycopene must contain a hydrogen bond donor (AH) and a Lewis base (B) separated by about 0.3 nanometers.

The AH-B units binds with a corresponding AH-B on the sweetness receptor to produce the sensation of sweetness. Sugar are used as sweeteners in cadies and many other food products.

This include boiled sweets, chocolates, toffees, bakery foods and cakes. Sugar provides flavor appeal to foods, and therefore is incorporated into many foods.  
Sweetness