3.2.1.1 Protein GapFill

Proteins are organic macromolecules built from  couscouspeptidesamino acidsadipose tissue, bound together into long chains.There are about 20 different amino acids which can combine to make a molecule of protein. Some of the amino acids can be built by the body from scratch – for this reason they are called 'dispensable'. If an amino acid cannot be built by the body from scratch, it is called  an insolublea high biological valuean essentiala miso amino acid and has to be provided as a part of a healthy diet.

There are  twentyninetwoeleven essential amino acids and if they are all present in a molecule of protein, such protein is called a complete protein and has a  insufficient valuehigh biological valuehigh energy valueincomplete value. If one or more of the amino acids is missing, the protein is considered  a solida stablean unstablea low biological value protein.

Protein  complementationcoagulationcomplementingcorrelation allows us to combine two or more sources of low biological value proteins to make a   fattyadequatewholetextured vegetable protein. An example of this is  hot dogspaghetti bolognesecheese on toastbeans on toast. Complete proteins occur mostly in  animal-derived foodsnutsfruits and vegetablesplant foods, but also in  couscousbreadgherkinsquinoa and  green peassoyolive oiltomatoes.

Proteins are necessary to build  all cells in the bodyunsaturated fatlardadipose tissue , enzymes and hormones. They can also be used as a  insolublesecondaryprimaryfree source of energy – this means that they are only used as a source of energy if other sources (carbohydrates and fats) are not available.
If a person eats too little protein, he or she may develop a disease called  night blindnessscurvykwashiorkorkidney stones. Too much protein can also be harmful for the body, causing harm to the liver and the kidneys.