PROTEIN OF HIGH QUALITY VALUE
What does high quality protein mean?
To speak of the quality or biological value (abbreviated in publications such as VB) of proteins is necessary to briefly explain its composition:
– Proteins are formed by very small units called amino acids. Amino acids determine the function of the whole protein. That’s to say, depending on the amino acids forming the protein, this will have a characteristic or other (and will be called one way or another).
– In the genetic code of each person, found in the nucleus of every cell, combinations of amino acids are written to form a particular protein. For example, the cell of the eye ” knows” the combination of amino acids needed to produce a blue eye protein.
Skin also contains proteins (collagen) such as muscle (actin and myosin), hormones (insulin, TSH, sex hormones, growth…), saliva and digestive enzymes, the body’s defense (leukocytes), etc..
– Being such important units, the body can make amino acids. However, there are 8 essential amino acids, meaning that the body can not synthesize them.
– So as the body can manufacture its proteins (hormones, collagen, enzymes,…) it needs essential amino acids, which must be provided through good nutrition.
– If a food is missing an amino acid, it is called “limiting amino acid”. For example, cereals have the limiting amino acid lysine and legumes the limiting amino acid methionine.
Therefore, we must combine foods with limiting amino acids with other foods containing that amino acid. People use to combine legumes with cereals (lentils and rice) to compensate for deficits of both amino acid and get high quality proteins
Limiting amino acid in food is one that is not provided in sufficient quantities to form a protein.
To illustrate an example, we can make an analogy between a protein and a flag. To form the Spanish flag (which would be the complete protein), you need 2 red and 1 yellow strips.
The bars represent the amino acids, which are the units that form proteins. If a “food” gives us only one red and one yellow strip, we can not make the Spanish flag (we miss another red strip). So red is the “amino acid” limitation of that suggested food.
The same applies to cereals. Although they provide certain amounts of lysine, these amounts are not sufficient to form a protein. Therefore it is said that lysine is the limiting amino acid of all cereals.
The body may produce amino acids, although there are eight of them that are essential, that’s to say, they can not be synthesized and must be supplied through food.
What are proteins of high biological value?
We say that a food contains protein of high biological value when it contains all the amino acids in sufficient quantities to form the proteins that the body needs.
The food which contains all amino acids in the more balanced proportions is the egg protein, which is assigned a biological protein value 1 (highest value).
All foods of animal origin contain proteins of high biological value. In contrast, in the plant world, it is difficult to find sufficient sources of protein in one food, so the wide range on a vegetarian diet must provide protein quality.
For the same reason, athletes who want to increase their muscle, generally make use of the excellent quality of the milk serum protein supplements.
TIPS TO ENSURE HIGH QUALITY PROTEINS FROM DIET
Quinoa dishes can provide high quality proteins. In the photo quinoa with onion and broccoli
In order to obtain the necessary needed proteins, we should take into account the following tips:
– Quinoa is a pseudocereal with high biological value proteins. We introduce it as a main dish or accompanying several meals a week.
– Refusing meat or fish, will not impede you to make a proper diet with nutritional value.
– Vitamin B12 (cobalamin) is as important as proteins. It is necessary for making blood cells. Enriching the diet with brewer’s yeast may be a good choice in vegetarian diets.
Composition of egg protein (amino acids)
Egg protein is considered the highest quality one because it contains all the amino acids needed to create life, or to be used by our body to make all needed proteins:
|Egg protein (albumin)||7.50||1.50||5.50|
|Egg protein (albumin)||9.40||7.50||6.40||6.50||4.20|
More information on quinoa.