Protein

Proteins are made up of ‘building blocks’ called amino acids, composed of carbon, hydrogen, oxygen and nitrogen (amino group). Proteins from different food sources contain different amounts of amino acids. Proteins from animal origin, such as meat, milk and eggs, contain all essential amino acids in balanced amounts. Essential amino acids are those that the body cannot make itself and must therefore be eaten. In contrast, proteins of vegetable origin (e.g., cereals and pulses) contain on their own insufficient quantities of some of the essential amino acids. By combining different foods, however (e.g., cereals with beans), adequate levels of all amino acids can be obtained without requiring protein from animal sources.

Proteins are required to build new tissue, particularly during the rapid growth period of infancy and early childhood, during pregnancy and nursing, and after infections or injuries. Excess protein is burned for energy.

The nutritional value of a protein food can be judged by its ability to provide both the quantity and number of essential amino acids needed by the body. Different food sources contain different groups of proteins, which are made up of different arrangements and amounts of amino acids. In general, proteins from animal sources are of greater nutritional value because they usually contain all the essential amino acids. Proteins from plant sources, such as cereals and vegetables, may be deficient in one or other of the essential amino acids. For example, the proteins obtained from wheat lack adequate quantities of one essential amino acid, and those from beans are deficient in another but the combiantion of cereal and pulses will provide a balanced diet.

Because the content of amino acids is different in each food, when they are eaten together they complement each other and the mixture is of higher nutritional value than the separate foods, and is as good as animal protein. It is important, that a variety of different types of protein foods are eaten.

Cooking can alter the amino-acid composition of protein and this usually results in desirable flavor and browning development. Very little nutritional value is lost.

Protein Intake

WFP recommends that 10 - 12% of the energy of the ration is derived from protein.

For instance for a daily ration of 2,100 kcal

• 10% = 210 kcal
• 210 kcal / 4 kcal/g = 52.5g of protein per day
• Maize contains 8.5g of protein/100g.
• Beans (Cowpeas) contain 23.5g of protein/100g.
• A ration made from 400g of maize (400 x 8.5% = 34g) and 100g of Cowpeas (100 x 23.5% = 23.5g) will bring 57.5g of protein.