Humans and animals use their tongues to taste. Our human tongue has many parts in it. So do animals. The human body has five senses tasting, smelling, touching, hearing, and seeing. The way we humans identify food is with our tongue and our nose. The tongue tastes the food  and the nose smells it.
    Our tongue has four main tastes  sweet, salty, sour, and bitter. The process  of  the tongue tasting to identify the food is simple. First when a person eats, the chemicals in the food dissolve in saliva. Saliva is slightly alkaline secretion of water. It means  saliva has (a ph more than seven). The saliva is created by the salivary glands. It is made up of mucin, protein, salts, and it is often a starch - splitting enzyme. Mucin is various  of complex  protein  found as viscid solution.