3.2.1.1 Protein GapFill

Proteins are organic macromolecules built from  peptidescouscousadipose tissueamino acids, 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  a misoa high biological valuean essentialan insoluble amino acid and has to be provided as a part of a healthy diet.

There are  nineeleventwentytwo 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 valueincomplete valuehigh biological valuehigh energy value. If one or more of the amino acids is missing, the protein is considered  a low biological valuea solida stablean unstable protein.

Protein  coagulationcorrelationcomplementingcomplementation allows us to combine two or more sources of low biological value proteins to make a   fattywholetextured vegetableadequate protein. An example of this is  beans on toasthot dogspaghetti bolognesecheese on toast. Complete proteins occur mostly in  plant foodsnutsfruits and vegetablesanimal-derived foods, but also in  quinoabreadcouscousgherkins and  green peassoyolive oiltomatoes.

Proteins are necessary to build  unsaturated fatlardall cells in the bodyadipose tissue , enzymes and hormones. They can also be used as a  secondaryfreeinsolubleprimary 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  kidney stonesnight blindnesskwashiorkorscurvy. Too much protein can also be harmful for the body, causing harm to the liver and the kidneys.