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Fermentation and the Food Culture of Ishikawa Prefecture

What is fermentation?

Fermentation is the process according to which microorganisms break down organic matter to obtain the energy required to stay alive, and make organic compounds such as alcohol and organic acid, as well as inorganic compounds such as carbon dioxide and hydrogen. Depending on the substances formed, the process is called alcohol fermentation, lactic acid fermentation, amino-acid fermentation, etc. Fermentation is used in various ways in our day-to-day lives.
For example, fermentation has been used since ancient times in the production of indigo dye, which makes a beautiful blue color, and potassium nitrate, which is the main component of black gunpowder. Knowledge about fermentation has been passed down to the present-day fermentation industry, where it is used in such processes as the production of pharmaceutical products and the purification of wastewater and waste material, and research is being carried out on further applications. However, the type of fermentation that we are the most familiar is that used in the production of food. Alcohol fermentation is used to make beverages such as sake and wine, and lactic acid fermentation is used to make yogurt and cheese. There are various kinds of fermented foods all over the world.

* The fine line between fermentation and decomposition
Microorganisms play a major role in the rotting (decomposition) of food. The fact is that fermentation and decomposition involve the same process of microorganisms breaking down organic matter to create a new substance. The difference lies in the nature of that new substance. If substances that are harmful to humans, such as hydrogen sulfide or ammonia, are created, the process is called “decomposition”, and if beneficial substances are created, it is called “fermentation”. Thus, the distinction is made according to the perspective taken.

* The characteristics of fermented foods
There are various types of fermented foods, but they all share some of the same characteristics

  1. They can be stored for a certain length of time.
    Generally speaking, fermented foods can be kept longer than the unfermented ingredients used to make them. For example, fresh milk goes bad easily, but fermented dairy products such as yogurt and cheese can be kept longer. It is thought that because lactic acid bacteria increase in number, they prevent the invasion of other bacteria that cause decomposition.
  2. They have a characteristic taste and smell.
    This is due to the fact that when microorganisms break down organic matter, they create amino acids that are the basis of olfactory components and flavor. Because microorganisms produce different substances, many fermented foods have a very distinctive flavor and smell.
  3. They promote good health.
    Decomposition causes the formation of substances with smaller molecules. This improves digestion and absorption of nutrients, and triggers the production of beneficial essential amino acids, vitamins and enzymes.