Classifications of Protein !

Proteins are classified by whether they have the ability to supply the body with all the essential amino acids .
Therefore , proteins are classified into 2 groups . 
The High Biological Value and Low Biological Value groups .

Proteins of High Biological Value are proteins that contains all the essential amino acids . Proteins of High Biological Values are mainly from Eggs , Dairy , Meat and Seafood .


Proteins of Low Biological Value are proteins that LACK ON OR MORE essential amino acids .
Proteins of plant sources are usually proteins of low biological value . However , Soya Beans are the only exception as it contains ALL essential amino acids :)
Although vegetarians refrain from eating meat , this does not necessarily mean that they cannot get all the essential amino acids from proteins of low biological value . 
Proteins of low biological value can be COMBINED is a way that the essential amino acids lacking in one type of food are present in the others . In other words , the protein content of one food COMPENSATES for the other's deficiency . Thus , they are also known as COMPLEMENTARY PROTEINS .