Fermentation is a reaction in which organic matter is broken down by the actions of molds, yeasts, bacteria and other microorganisms, and transformed into simpler substances. It is distinguished from putrefaction in that the results are useful to humans; in other words, it is an anthropocentric concept. As a result of experimentation in the mid-19th century, Louis Pasteur expressly denied the “spontaneous generation theory,” which had held that microorganisms were generated from inorganic matter by natural processes. He elucidated that fermentation was a phenomenon that occurred due to the actions of yeast and other microorganisms that grow under anaerobic conditions in the absence of oxygen. Later, forms of fermentation that required oxygen and produced large amounts of substances useful to humans, such as acetic fermentation, in which acetic acid is produced from ethyl alcohol by acetic bacteria, also came to be included under fermentation as oxidative fermentation.
There is no established theory about when and in what manner humankind came to eat fermented foods. Recent research, however, indicates that about ten million years ago, before humankind’s ancestors split off from other anthropoid apes in Africa, they acquired digestive enzymes capable of metabolizing ethyl alcohol. It appears to have been an adaptation allowing them to eat fruit fallen from trees that had fermented and contained ethyl alcohol when humankind’s ancestors, who had mostly eaten fruit atop trees, expanded their terrestrial activities.
The possibility has been noted that later on, about three to four million years ago, underground storage organs of various plants like potatoes (rhizomes, tubers, tuberous roots, etc.) may have been buried and allowed to ferment. While none of this research has gone beyond the postulation, since it was about 800,000 to 1 million years when humankind began handling fire, it indicates a far longer history of processing food by fermenting it than by cooking it using fire.
By about 10,000 years ago, humankind had expanded into nearly all land areas on Earth. After that, humankind mostly settled down and switched from lifestyles centered around hunting and gathering to ones centered around farming and stock breeding. Regarding fermented foods, at first, those that had fermented naturally were used, but in continuing to ferment specific foods in specific places, people sharpened their ability to ferment foods, and those involved in production created environments where they could produce intended fermented foods.
This was the domestication of microorganisms. Not only did our ancestors domesticate animals and plants, over a long period of time, they also created invisible microorganisms with useful properties that carried out fermentation.
While there are fermented foods that have come to be enjoyed worldwide, such as bread, yogurt, and beer, there are also fermented foods such as narezushi (fermented fish sushi) and natto that are passionately loved only in certain regions. In all parts of the world, there are many fermented foods that are essential to mention when talking about local food culture. In those areas, they are used in a variety of ways—as staple foods, supplementary foods, seasonings, and refreshments. This exhibition elucidates how fermented foods are produced, consumed, and sold as a human cultural activity based on fieldwork performed by researchers around the world.
* The English title has slightly been changed from the panel.
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