Question

A piece of teach starts tasting sweet when the chewed for a long time .Why?​

Answer 1

Explanation:

The bread tastes sweet after chewing it for a long time because of the digestion of polysaccharides into disaccharide maltose with the help of salivary amylase which is secreted along with the saliva. ... Maltose is formed by 2 molecules of glucose and thus is sweet in taste

Answer 2

Answer:

Bread is an excellent source of proteins, vitamins, minerals, fibre and complex carbohydrates.

The digestion of the food starts as soon as we put food in our mouth. Our teeth cut the food into small pieces and the salivary glands secrete saliva that mixes with these food materials. The saliva contains an enzyme called salivary amylase which hydrolyses starch into maltose.  

It breaks down starch in bread into simpler sugars (maltose) which give a sweet taste, while chewing the bread for a longer time, more mixing, for enzymatic action and hence you perceive it as sweet.

Hope it helps you :)