This is a very familiar source of food to Japanese people. Soybeans are rich in fat, vitamins, minerals, and fibers as well as protein. Soybeans also contain soy isoflavone and good for health.　

　It is also called "Field Meat" and its amino acid score is 100, which is the highest. It means soybeans contain 9 essential amino acids necessary to produce protein and few plants have such a high score, though many animals do.

As actually soybeans are produced mainly as animal feed. About 70% of them are used for animal feed. Humans eat only about 10% of the soybeans produced. Beef and pork give us only 10% of the protein which cows and pigs ate, which makes us realize how inefficient it is to eat them.

Unlike worms and insects, soybeans are widely eaten. Soy meat or tofu hamburg steak look like animal meat. Soybeans now attract attention as healthy “meat” which even vegetarians could eat and could be easily replaced with beef and pork.

There are, however, some demerits. As the demand for soybeans increases, the amount of soybeans produced in the world has also increased from 30.000.000 tons in the1960’s to 320.000.000 tons.
This is a 10.7 times increase. This increase is overwhelming compared with wheat (3.1 times increase), rice(3.2 times increase), and corn (4.9 times increase).
The increase in the production of soybeans is said to be the main cause of the destruction of the native ecosystem in Latin America, where a wide range of the forest, grassland and steppe are turned into agricultural land when soybeans started to be widely produced.
The loss of forest could damage the environment of the whole earth and we have to deal with the problem.

Fish meal is produced by crushing dried small fish such as anchovy into powder.
It has a high protein content, which is more than 60%, and has a high amino acid score (many kinds of fish have the highest amino acid score 100).
It is an important feed to farm fish. About 7.000.000 tons of fish meal was produced in 2000, it dropped, however, to 4.500.000 tons in 2010. In Peru, where the largest amount of fish meal is produced, they control the amount of fish caught for the purpose of preserving fish resources and stabilizing its price.
Therefore, we cannot expect the increase in the production of fish meal. We also have to find a substitute of this protein source.

You may have never thought that this could be a protein source but actually they are a potential protein source. They grow by photosynthesis and the productivity per unit area is very high.
They can produce 15 times as much protein as soybeans a year per unit area.
They can grow in a water tank, so we can grow them where we can’t grow plants.
They may, like worms and insects, grow in outer space, which is now being studied.
Currently, however, it is not in practical use due to their high prices and unique fishy smell. Still it is a very promising source of protein.

　 Scientists are now trying to produce yeast fungi or certain bacteria using methine and electricity, which could be used as animal feed.
According to the companies working on the mass production of bacteria which eat methine say that they could produce them at a low cost and therefore they have a high price competitiveness.