What does the biological value indicate?
Everyone has probably heard of the biological value of food proteins because many companies advertise the high biological value of their products. But what does biological value actually mean? We explain it to you in this blog post.
Introduction: The importance of proteinsProteins (also known as proteins) are extremely important for our body, as they play an important role in many vital processes in the body. They are also the basic building block of all cells.
Proteins are made up of their building blocks - the amino acids -. There are a total of 20 proteinogenic amino acids in the human body, which means that these amino acids are needed to build a protein. Furthermore, amino acids are divided into non-essential, conditionally essential and essential amino acids. Essential means that the body must absorb these amino acids with food. Consequently, they cannot be produced in the body itself.
In our diet, around 12 to 15% of our daily energy intake should consist of proteins .Quality of the proteins
It is not only the quantity that is decisive for protein intake, but also the quality of the proteins. The more the composition of the amino acids of a dietary protein corresponds to the body's own protein, the higher the so-called biological value or quality of the proteins. This means that the less of this protein needs to be consumed to cover requirements.
Biological valueThere are numerous methods for evaluating dietary proteins, but biological value is probably the best known. In comparison to other concepts, the biological value also includes the digestibility of a protein
.In addition, the biological value is based on the whole egg protein. Whole egg protein has a biological value of 100 or 1.0 (i.e. 100%) and was defined as the reference value as it was the protein with the highest biological value at the time the definition was established.
As a result, all other proteins are compared with this value. The biological value is therefore a measure of how efficiently dietary proteins can be converted into the body's own proteins. If a dietary protein is better utilised by the body than the egg protein, it has a biological value of over 100; if a protein is utilised less efficiently than the egg protein, the value is below 100.
In this context, the essential amino acids are of particular importance. The more proteinogenic amino acids a food contains and the higher the content of essential amino acids, the higher the quality of the protein. On the other hand, if only a few essential amino acids are present or one is completely missing, the protein cannot be fully formed and the biological value is low.Examples of the biological value of a dietary proteinFood | Biological value |
Vollei (reference value) | 100 |
Potatoes | 95 |
Soy | 84 |
Cow's milk | 85 |
Rice | 83 |
Beef | 87 |
Beans | 73 |
Wheat flour | 59 |
Animal protein usually has a higher biological value than plant-based protein sources, as the amino acid composition is more similar to that of the human body. However, many plant proteins also perform very well, as you can see in the table above. This means that potatoes, soya and rice, for example, have a similar biological value to animal protein sources.
The biological value in the body can be enhanced by combining individual protein sources. By specifically combining proteins with different amino acid compositions, foods with a previously low biological value can be combined to create a complete meal. For example, a mixture of potato and egg protein has the highest biological value of all protein mixtures analysed at 136.
Biological value by combining different protein sourcesFood | Biological value |
65% potato and 35% whole egg | 136 |
85 % rice and 15 % yeast | 118 |
55% soya and 45% rice | 111 |
55 % potato and 45 % soya | 103 |
52 % beans and 48 % maize | 99 |
It is important to note that the value 100 for whole egg protein does not mean 100% conversion in the body. This is because the value 100 is only a reference value. It is therefore possible to achieve biological values above 100 by combining different protein sources. However, as it is impossible to build up more than 100 g of the body's own protein from 100 g of supplied protein, it is understandable that the biological value is not an absolute indication of the conversion of dietary protein in the body.
An example: Although pea protein is an abundant source of the essential amino acids lysine and leucine it contains less of the amino acids cysteine and methionine. Rice protein is rich in methionine and cysteine, but contains little of the amino acid lysine. A combination of both protein sources leads to a higher biological value, as the amino acids complement each other.
Nutri-Plus vegan protein powder
In order to increase the biological value of our protein powders and ensure an optimal supply of all essential amino acids, we combine different protein sources with each other. This is why we offer our 3K protein powder made from wheat, soya and pea, our soya pea protein and our pea rice protein.