The sense of taste and smell allow us to separate undesirable or even lethal foods from those that are pieasant to eat and nutrition. Both senses are strongly tied to primitive emotional and behavioral functions of nervous system.
Sense of taste:- Taste is mainly a function of the taste buds in the mouth, but it is common experience that one’s sense of smell also contributes strongly to taste perception.
Primary sensation of taste:- There are five general groups of primary sensation of taste.
1. Sour Taste- The sour taste is caused by acids, that is by the hydrogen ion concentration.
2. Salty Taste-It is caused by ionized salys, mainly by the sodium ion concentation. The cations of the salts, especially sodium cations, are mainly responsible for the salty taste, but the anions also contribute to lesser extent.
3. Sweet Taste- It is not caused by any single class of chemicals. Some of the types of chemicals that cause this taste includes sugars, alcohals, aldehydes, ketones, amides esters etc. It is very interesting that slight changes in the chemical structure such as addition of a simple radical can change the substance from sweet to bitter.
4. Bitter Taste- It is also not caused by any single type of chemical agent. Two particular classes of substances that cause bitter taste are
A. Long chane organic substances
B. Alkaloids
5. Umani Taste-Umani is a Japanese word meaning delicious. Umani is the dominant taste of food containing L- glutamate such as meat extracts and ageing cheese.

 Dr. Priyanka Dadupanthi