prtein

                                  PROTEIN

protein are large, complex, organic compounds made up of carbon, hydrogen, oxygen and nitrogen. The presence of nitrogen. The presence of nitrogen distinguishes proteins from carbohydrates and fats. Apart from nitrogen some other elements such as sulphur, phosphorus, copper and iron are also found in some proteins.

The basic of units of proteins are the amino acids. Each amino acid contains an acidic group and an amino group. Protein consist of chains of amino acids that are linked to each other by a peptide linkage

SOURCES OF PROTEINS

we obtain protein from two main dietary sources:

1. ANIMAL SOURCES:  Milk, meat, eggs, cheese, fish and fowl. These proteins contain all the EAA in adeuate amounts.  

PROTEIN CONTENTS OF DIFFERENT GROUPS OF FOODS

FOOD GROUPS                                                       PROTEIN CONTENT IN GRAM

Egg                                                                             12-14

Meat fish                                                                     18-20

Milk fresh                                                                   3.5-4

Milk dried skimmed                                                   26-28 

Oilseeds and nuts                                                         18-40

Pulses                                                                           18-24

Cereals and milets                                                      6-14

Suplementary Action of proteins 

Man derives protein from variety of food sources . Some sources like cereal proetins are dificient in lysine and threonine and pulse proteins are lacking in methionine . These are known as Limiting amino acids.