Goja an authentic popular Bengali sweet made of refined flour and milk, then fried with oil. The sensitivity of the chemical in the perception of sweetness, which varies for individuals and species, has been understood only in recent times. The model theorist currently accepted involves multiple sites of binding between the receptor and the sweet substance.
Some studies indicate that the sensitivity to sugars and sweetness has roots evolutionary very old, already present as chemotaxis even in bacteria furniture such as the Escherichia coli. The threshold of perception for sweet is the highest among the basic tastes, being enabled to about 1 part in 200 of sugar in solution. For comparison, the bitter, which has the lowest sensitivity threshold, is already perceived to 1 part in 2 million quinine in solution.
In the natural environment where the human species evolved the cake was an indicator of wealth nutritional food, while bitterness was associated with toxicity. The high perception threshold of the dessert would then set up the primates and hominids , our forebears, to seek sweet foods and nutrients and to avoid bitter foods. Even among primates eaters of leaves there is a tendency to prefer the young leaves, richer in protein and poorer in toxic substances, the mature leaves. The taste for sweet then has an ancient evolutionary origin, since, despite processing of food has changed consumer habits, the physiology of the human has remained mostly unchanged.