In ancient life, one of the biggest problems that humans faced was accessing and preserving food. After humans transitioned to agricultural life, the former problem was solved. However, the latter problem persisted, and even got exacerbated by farming: how would they keep food from rotting or molding for long amounts of time?
One possible approach was keeping the food cold, which is really accessible to us today thanks to the invention of the fridge. However, in a world without electricity, it was out of the question. There were warehouses filled with ice and food, which did work temporarily. However, the ice eventually had to melt, once again exposing the food to possible contamination. Societies that lived in cold places, such as the Nords, did use this method.
Another approach was pulling the moisture out of the food. The science behind this wasn’t known back then, but we now know that the lack of water prohibits the enzymes of saprophytic pathogens from working. You could dry the food in many ways: smoking it over a fire for long periods of time without cooking, covering it with salts that pull water out using osmosis... The disadvantage of this is that the food becomes extremely dry and, if salted, salty. This required rehydrating the food when it was to be used. And before water sanitation became widespread, this approach was quite difficult.
Other preservation methods were found occasionally by coincidence. For example, keeping milk inside sacs made with the gastrointestinal tract of slaughtered animals (specifically, their stomach and intestines) caused it to curdle in a creamy and watery form, which people noticed made it last a lot longer. Although the reason behind it wasn’t known then, such ways of preserving food quickly became widespread. Leaving dough mix or fruit juice outside for some time in certain conditions, putting cabbage in a saline solution, all are different methods of doing the same thing: fermentation.
According to the Cambridge Dictionary, fermentation is defined as “a process of chemical change in food or drink because of the action of yeast or bacteria, which may cause it to produce bubbles or heat, or turn sugars in it into alcohol.” While it isn’t that appetizing to say it, fermentation is technically making certain microorganisms digest your food before you consume it. This, in turn, creates either substances or conditions which prohibit other microorganisms (including the bad ones) from making food go bad. This lowers the energy content that the product initially had; however, since it was digested up to some point before, your digestive system no longer needs to work as hard to access those resources. The result? Improved and more accessible nutritional content, better digestibility, and often better taste.
Such reasons caused humanity to fall in love with fermentation. We used fermentation on a lot of our ancient foods: bread dough rose and became tastier when fermented, alcohol proved a sanitary (and intoxicating) solution to hydration, and vegetables like cabbage softened up and became tastier when made into sauerkraut or other fermented products. And, even though our ancestors had no idea, the presence of good microbes in fermented foods made them superfoods: once ingested, the microorganisms settled in their guts and acted as prebiotics, which drastically improved their immune system’s function.
In the modern day, refrigeration and industrial food processing has taken the place of fermentation and curing. We fill packaged foods to the brim with chemical preservatives and throw any leftovers into the refrigerator. Of course, it is much simpler to do that instead of potentially waiting for days for our food to ferment. But this, in turn, has caused huge problems to our natural gut microbiome. Some even view fermentation as being equivalent to molding, because of how similar the processes are. Our taste buds are shifting ever so slightly away from our multi-millennia-old friend every single day, adapting to our modern preferences. However, for those willing to go the extra mile, fermentation remains one of humanity’s best food practices and our first exposure to biotechnological applications.
Sources: Taveira, I. C., Nogueira, K. M. V., Oliveira, D. L. G. D., & Silva, R. D. N. (2021). Fermentation: Humanity's oldest biotechnological tool. Frontiers for Young Minds, 9, Article 568656. https://doi.org/10.3389/frym.2021.568656
Sommer, K., McFall-Ngai, M., & Tipton, K. (2023). Fermentation technology as a driver of human brain expansion. Communications Biology, 6, Article 1208. https://doi.org/10.1038/s42003-023-05517-3
The Nobel Prize. (1907). The Nobel Prize in Chemistry 1907. NobelPrize.org. https://www.nobelprize.org/prizes/chemistry/1907/buchner/facts/
Pasteur, L. (1857). Mémoire sur la fermentation appelée lactique Memoir on lactic fermentation. In Nature Scitable. https://www.nature.com/scitable/topicpage/yeast-fermentation-and-the-making-of-beer-14372813/