“The proliferation of [microorganisms] in fermented vegetables enhances their digestibility and increases vitamin levels. These beneficial organisms produce numerous helpful enzymes as well as antibiotic and anticarcinogenic substances. [They] not only keep vegetables and fruits in a state of perfect preservation but also promotes the growth of healthy flora throughout the intestine.” —Sally Fallon, Nourishing Traditions
Food fermentation is a practice that has been discovered and revered by every traditional culture in the world, and for good reason. Fermentation is inexpensive, increases the shelf life of food, and provides numerous health benefits to foodstuffs, including:
- Fermented foods improve digestion by introducing beneficial microflora to digestive systems. These microbes replenish the gut with microbes that may have been killed off by the consumption of antibiotics or chlorinated water, while also introducing new genetics to that are better adapted to environmental pathogens and stressors.
- Raw fermented foods are rich in enzymes that help the body properly digest, absorb, and utilize nutrients.
- Fermentation can greatly increase the amount of B2, B6, B7, and B9 in food.
- Fermented foods may increase longevity. Many traditional cultures claim that their fermented foods contribute to their health. For example, in post-WWII Japan, villages that consumed large quantities of miso soup (a double fermented broth) has significantly lower rates of cancer and radiation sickness.
Further, fermentation enhances flavors. Our most prized gourmet foods and drinks (e.g. chocolate, high end cheeses, breads, cured meats, coffee, tea, and alcoholic beverages) are all created via fermentation.
The Fermenting Fungi
Though many of the more familiar fermented foods (e.g. sauerkraut and kimchi) are primarily created by bacteria, yeasts and other micro fungi are always involved in these ferments to some degree. There are also some fungal-dominated ferments that have been developed around the world, with:
- Ales, beers, wines, meads, and alcoholic ciders are all produced by the fermentation of various yeasts. Saccharomyces cerevisiae is the most common commercial yeast, though Brettanomyces species are used in many modern lambics. Sake is made through a multi-stage process that invoves Saccharomyces sake and Aspergillus oryzae.
- Bread is leavened by trapping the gas expelled by Saccharomyces cerevisiae in sticky doughs prior to baking.
- Tempeh is an Indonesian ferment made by growing the mold Rhizopus oligosporus on grains or legumes (e.g. soybeans).
- Miso is a twice-fermented product created by packing rice or barley myceliated by Aspergillus oryzae into a crock for months or weeks. The liquid byproduct of this process is sold as tamari.
- Gourmet white and blue cheeses (e.g. Camembert, Brie, Gorgonzola, and Roquefort) are produced by intentionally inoculating cheese curds with Penicillium camemberti and Penicillium roquefortii,
- Sufu is a form of fermented soybean curd made by inoculating dry firm tofu with the spores of Actinomucor elegans, Mucor sufu, Mucor rouxanus, Mucor wutuongkiao, Mucor racemosus, or Rhizopus species and then soaking the tofu in a brine of rice wine, vinegar, chili peppers, or sesame oil.
- Ragi Tapai is a term applied to the fermentation of various carbohydrate-rich foods (e.g. cassava, cooked white or glutinous rice, or sweet potatoes) that have been cooked, cooled, and inoculated with a mold and yeast.
- Ang-Kak (red yeast rice) is made by inoculating non-glutinous rice with the mold Monascus purpueus. It has been used since the Tang Dynasty in China (ca. 800 CE) as a medicine for invigorating the body, improving digestion, and revitalizing the blood.
- Katsuobushi (bonito) flakes are made from skipjack tuna (Katsuwonus pelamis) that has been smoked and fermented with Aspergillus glaucus for several weeks. These flakes and kombu kelp are the main ingredients of dashi, the broth commonly used as a miso soup base.
Cultivating Fermenting Fungi
Small-scale production of the above often requires the importation of fungal cultures, though some can be “wild fermented” by the yeasts found on the surface of the ingredients. It is also possible to easily perpetuate these cultures using the same techniques found in mushroom cultivation. Maintaining one’s own collection of fermenting fungal cultures thus enables a person to derive all the above benefits at a fraction of their normal cost. Home brewers commonly keep a collection of various strains of yeasts for different types of alcoholic drinks and Indonesians keep stock of their tempeh cultures. Hopefully, as the skills of fungal cultivation become more commonplace in the coming yeasts, these fermented foods and others like them will also rise in popularity.