Chapter 4
Basic Concepts and Equipment
Fermentation broadly refers to the transformative action of microorganisms. While biologists specifically define it as anaerobic metabolism (energy production without oxygen), the culinary definition includes both anaerobic processes like alcohol and lactic acid fermentation, and aerobic processes like vinegar, tempeh, and molded cheeses. The practice fundamentally involves manipulating environmental conditions to encourage beneficial organisms while discouraging harmful ones.
In fermentation, the food being transformed is called the substrate-both food for microbes and the medium on which they grow. Raw foods naturally host diverse microorganisms that exist in communities, never in isolation. As Lynn Margulis and Dorion Sagan explain, bacteria live in teams that respond to and reform their environment, aiding each other with complementary enzymes and metabolic products.
Fermentation falls into two broad categories: wild fermentation, which relies on organisms spontaneously present on the food or in the environment; and culturing, which introduces specific isolated organisms or established communities to initiate fermentation. Most fermentation cultures (starters) involve transferring a small amount of active ferment into a fresh batch-a practice technically called "backslopping." All introduced cultures originated as spontaneous wild fermentation events that people especially liked and learned to perpetuate.
Creating selective environments is fundamental to fermentation practice. Submerging vegetables under liquid excludes air, preventing mold growth while encouraging lactic acid bacteria. Similarly, air-locked containers for alcoholic beverages prevent aerobic Acetobacter from turning alcohol into vinegar. Other factors that may be manipulated include oxygen access, carbon dioxide release, moisture content, salinity, acidity, humidity, and temperature.
Fermentation involves dynamic microbial communities that shift over time. In sauerkraut, Leuconostoc mesenteroides typically dominates initially, but as it produces lactic acid and alters the environment, it's succeeded by Lactobacillus plantarum-similar to ecological succession in forests where each dominant species changes conditions for subsequent growth.
While some contemporary fermentation literature emphasizes chemical sterilization, cleanliness rather than sterility is generally sufficient. Working with clean hands, utensils, and equipment is important, but sterile conditions are unnecessary for most fermentation. The author addresses the common concern about different ferments contaminating each other, noting that while different cultures may subtly influence one another through the air over time, cross-contamination is rarely a significant issue.
Water quality is crucial for fermentation, with chlorine being the biggest concern as it's specifically added to municipal water supplies to kill microorganisms. Salt creates selective environments that encourage specific microorganisms like lactic acid bacteria while inhibiting others. For most vegetable ferments, salting can be done to taste without precise measurement, but certain ferments like meat curing or long-aged miso require specific salt proportions for safety and preservation.
The need for fermentation vessels has driven human inventiveness throughout history. Different vessel shapes offer different functional benefits: wide mouths are important for solid foods like sauerkraut to allow hand access, while wide vessels are ideal for aerobic processes like kombucha or vinegar where fermentation is most active at the oxygen-rich surface. For wines or meads fermenting to dryness, narrow-necked vessels with airlocks are preferable to minimize surface area where vinegar production could occur.
Chapter 5
Fermenting Sugars into Alcohol
Alcohol is a magical substance with transformative power-lightening moods, dissolving inhibitions, and serving as a social lubricant and sexual catalyst. It functions as a holy sacrament in both indigenous traditions and major world religions, connecting humans with gods and ancestors across cultures. In moderation, drinking promotes health and longevity, while providing crucial B-vitamins through fermentation. Yet alcohol's power brings dangers too-nausea, impulsive behavior, addiction, illness, and even death.
Yeasts are the microorganisms that ferment sugars into alcohol and carbon dioxide. Though invisible to the naked eye, their bubbling action has been observed throughout human history. Among the first microorganisms identified and studied, fermentation yeasts-particularly Saccharomyces cerevisiae-can function in both aerobic and anaerobic environments, though alcohol accumulates only without oxygen.
Mead-honey wine-is perhaps the simplest ferment, requiring only raw honey diluted with water. The yeasts naturally present in raw honey remain dormant until water content exceeds 17%, at which point fermentation begins spontaneously. The dilution ratio is flexible: typical proportions range from 1 part honey to 4 parts water for standard mead, while Polish pultorak uses 1 part honey to just half part water, and Mexican baalche dilutes honey with up to 17 parts water.
Traditional meads across cultures incorporate botanical ingredients that contribute more than just flavor. Ethiopian t'ej uses twigs and leaves of Rhamnus prinoides (gesho or woody hops), while Mayan-descended Lacandon people make baalche with Lonchocarpus violaceus bark in hollow log vessels called canoas. These botanicals provide yeasts, acids, tannins, nitrogen, and growth factors that stimulate fermentation.
Fruit and flower meads capitalize on seasonal abundance, with fresh fruits providing natural yeasts, acidity, and sometimes tannins-all beneficial for fermentation. Meads can be enjoyed "green" (young and moderately alcoholic) or fermented longer and aged for years. For continued fermentation, transfer the liquid to a narrow-necked vessel filled to minimize surface area, then use an airlock to protect from oxygen and prevent Acetobacter from turning alcohol into vinegar.
Wine is essentially fermented grape juice, with grapes providing the perfect balance of sugars, acids, and tannins for fermentation. The natural yeasts on grape skins readily initiate fermentation. Wine culture originated in the Zagros Mountains (modern Armenia/Iran) around 7000 BCE, gradually spreading throughout the Mediterranean through Canaanite traders.
Cider and perry are fermented apple and pear juices, traditionally made from fruit varieties too small, mealy, or astringent for eating. Raw, fresh-pressed juice contains natural yeasts and will ferment spontaneously, while pasteurized juice requires introduced yeasts. During early fermentation, cider often foams vigorously, so air locks should be added only after this initial phase subsides.
Country wines are alcoholic beverages made by infusing fruits, flowers, vegetables, herbs, or spices in sugar water. Unlike grape wine or cider, the challenge isn't juicing but rather extracting flavor. Sugar offers advantages of being cheap and neutral-flavored, allowing other flavors to shine. Beyond sugar and honey, alcohol can be fermented from virtually any concentrated carbohydrate source including maple syrup, sorghum, agave, jaggery (palm sugar), rice syrup, and barley malt.
Plant saps are widely fermented into alcohol across the world. Palm wine, popular in tropical regions, is made by tapping palm trees and collecting the flowing sap, which ferments rapidly due to natural yeasts introduced by insects. Within hours it reaches 4% alcohol, and within a day 7-8%. Desert succulents like agave provide aguamiel (honey water), which ferments into pulque, a unique, sometimes slimy beverage with refreshing sweet-acidic qualities.
Chapter 6
Fermenting Vegetables
Vegetable fermentation follows one fundamental principle: keeping vegetables submerged under liquid creates a selective environment where oxygen-dependent organisms cannot grow, encouraging beneficial acidifying bacteria. Beyond this basic technique, approaches vary widely across cultures-from wilting vegetables in brine or sun to pounding fresh ones, fermenting single vegetables or complex mixtures with spices and other ingredients, fermenting for days or years, using different vessels, locations, and techniques.
Lactic acid bacteria (LAB) naturally occur on all plants, though in small numbers. As vegetables ferment, the environment shifts from heterofermentative bacteria like Leuconostoc mesenteroides (producing lactic acid, CO2, alcohol, and acetic acid) to more specialized acid-tolerant homofermentative LAB like Lactobacillus plantarum in later stages. This symbiotic relationship between different types of bacteria is crucial for successful fermentation.
Fermentation became widespread in temperate regions as a strategy for preserving vegetables through winter when fresh produce wasn't available. While fermentation doesn't create additional vitamin C, it significantly slows its loss by maintaining a protective carbon dioxide atmosphere. This preservation of nutrients was crucial historically, as demonstrated by Captain James Cook's famous use of sauerkraut to prevent scurvy among his sailors.
The basic technique involves chopping or grating vegetables, salting them lightly, pounding or squeezing until moist (or soaking in brine), packing tightly into a vessel so they're submerged under liquid, and waiting. This simple "Chop, Salt, Pack, Wait" process underlies most vegetable fermentation traditions.
While salt isn't absolutely required for fermentation, it significantly improves taste, texture, and preservation potential. Salt pulls water from vegetables through osmosis, keeps vegetables crisp by hardening pectins and slowing pectin-digesting enzymes, creates a selective environment favoring lactic acid bacteria, and extends preservation by slowing fermentation and mold development.
Fermentation time depends on taste preferences, temperature, and salt levels. At cooler temperatures (50-60F/10-15C), fermentation proceeds slowly, creating superior products, while warmer temperatures accelerate fermentation but may yield inferior flavors and shorter shelf life. Salt concentration also affects speed-saltier ferments in summer heat slow down fermentation.
Surface growth is normal where vegetable brine meets oxygen-rich air. Kahm yeast-appearing beige with wave-like textures-and white mold commonly develop but aren't cause for alarm. Simply remove weights, skim off growths with a wide spoon, and discard. While removing all growth may be impossible, white molds aren't harmful, though colored molds indicate sporulation and should be completely removed.
Sauerkraut, the most familiar fermented vegetable in Western culture, consists primarily of shredded cabbage and salt, often spiced with juniper berries or caraway seeds. Kimchi represents the soul of Korean cuisine-so culturally significant that when eaten, it "effervesces on the tongue" and serves as a palate cleanser that "shoots straight to the brain." The diversity encompasses countless varieties including water kimchi (tongchimi) with floating ingredients like cabbage, Asian pear, and pine nuts in tangy brine, and "salad" kimchi (geotjeoli) eaten unfermented.
Chinese vegetable fermentation represents the ancestral tradition that inspired kimchi, sauerkraut and countless other global ferments. Each Chinese province maintains distinctive vegetable fermentation methods-some using starters like chiang (similar to miso) or qu (mixed fungal-bacterial culture), others employing dry-salting or brining, and many incorporating rice gruel or starchy rice-washing water as a medium.
Chapter 7
Fermenting Sour Tonic Beverages
Sour tonic beverages form a diverse family of ferments that are acidic, somewhat sweet, sometimes lightly alcoholic, and packed with beneficial bacteria. These invigorating, refreshing drinks make perfect sense as continuous rhythms in your life-each batch becomes the starter for the next.
Most require starter cultures that are self-perpetuating. Some starters like ginger bug can be easily created at home, while others like kombucha and water kefir require obtaining SCOBY (symbiotic community of bacteria and yeast) cultures from enthusiasts or commercial sources. These cultures grow abundantly with use, making them easy to share and spread.
Carbonation enhances these tonic beverages but requires careful attention. To carbonate, transfer actively fermenting liquid to pressure-resistant bottles like bail-top bottles, beer bottles with crimp caps, or soda bottles. For safety, bottle some portion in plastic soda bottles to monitor pressure by squeezing-when the bottle becomes firm, refrigerate all bottles immediately.
Ginger beer starts with a simple "ginger bug" starter made from grated ginger, sugar, and water. Stir frequently and add more ginger and sugar daily until vigorously bubbly, typically within a few days. For best results, use organic ginger, as conventional imports are often irradiated, destroying natural yeasts and bacteria.
Kvass is a refreshing, effervescent sour beverage traditionally made from old bread, iconic in Russia, Ukraine, and Eastern Europe. So culturally significant is kvass that it has become a symbol of national identity, with modern Russian producers marketing it as a patriotic alternative to Western soft drinks like cola.
Water kefir is a versatile culture-also known as tibicos, tibis, sugary water grains, Tibetan crystals, Japanese water crystals, and bees wine-that ferments virtually any carbohydrate-rich liquid. The culture appears as small, whitish translucent granules composed primarily of lactic acid bacteria and yeasts, particularly Lactobacillus hilgardii, which produces the polysaccharide gel housing the microbial community.
Kombucha is sugar-sweetened tea fermented by a community of organisms into a delicious sour tonic beverage resembling sparkling apple cider. It's produced by a SCOBY (Symbiotic Community of Bacteria and Yeast), a rubbery disk that floats on the fermenting tea's surface. While it's been promoted for health benefits throughout Central and Eastern Europe over the last century, it only began spreading in the US during the mid-1990s through grassroots channels. By 2009, commercial kombucha had exploded, with US sales quadrupling from $80 million to $324 million in just one year.
Many have observed that the kombucha SCOBY closely resembles mother-of-vinegar, with some describing kombucha as immature vinegar. Vinegar forms when aerobic Acetobacter bacteria metabolize alcohol into acetic acid-wine becomes wine vinegar, cider becomes cider vinegar, and so on. Contrary to traditional belief, making vinegar doesn't require a mother culture. The omnipresent Acetobacter will eventually transform any preservative-free alcoholic beverage exposed to air into vinegar.
Chapter 8
Fermenting Milk
Fresh milk was largely a 20th-century phenomenon enabled by refrigeration technology. Throughout history, most people consumed milk primarily in fermented forms which stabilized the highly perishable substance. Fermentation transforms milk in countless ways-from yogurt and kefir to countless regional variations developed wherever humans kept milking animals.
Traditional fermented milks evolved through empirical methods, using "backslopping" (using previous batches as starters) rather than defined scientific cultures. These traditional products vary naturally by season, location, and maker, contrasting with modern standardized commercial products. Despite traditional ferments often testing higher in nutrients and flavor preference, corporations and researchers frequently push standardized versions in the name of "hygiene" and profit, contributing to the extinction of diverse cultural practices.
Clabber, from Gaelic "clabar" meaning mud, refers to naturally curdled fermented milk. As lactic acid bacteria digest lactose, they create acid that causes casein proteins to separate and rebond into a continuous meshwork, transforming liquid milk into a fragile solid that separates into curds and whey.
In traditional practice, raw milk was simply left at room temperature until it thickened naturally. The fermentation time varies with ambient temperature-from less than a day in summer heat to weeks in refrigeration. Despite modern fears about spoiled milk, properly soured raw milk remains safe to consume because the beneficial bacteria that cause souring also protect it from pathogens.
Yogurt, the world's most popular fermented milk, is distinguished by its thick, creamy consistency and mild tartness. Unlike clabber, yogurt relies on thermophilic (heat-loving) bacteria that require incubation at 110-115F (43-46C). The yogurt-making process begins with heating milk to at least 180F (82C), which restructures casein proteins for thicker yogurt. After cooling to 115F (46C), starter culture is added (about 1 tablespoon per quart), and the mixture is incubated for 3-8 hours.
Kefir is a fermented milk beverage that's thicker than milk, ranges from mildly tart to super-sour, and uniquely effervescent. Often called "the champagne of milks," kefir contains yeasts that produce alcohol levels from negligible amounts up to 3 percent depending on fermentation length. Unlike other milk cultures that use fermented milk as starter, kefir relies on a distinctive SCOBY-a whitish, rubbery mass with undulating surfaces resembling cauliflower florets or small brains.
Cheeses are condensed forms of milk created by removing varying amounts of whey-less removal produces soft cheeses while more creates harder cheeses that can be preserved longer. The incredible diversity of cheese reflects human inventiveness across different regions, with variations coming from different animals, pastures, climates, seasons, culturing methods, coagulation agents, temperature treatments, aging conditions and countless other factors.
"Milk" now refers to any creamy liquid of substance, including plant-based alternatives. Any nut or seed can be extracted as milk or made into cheese. Hickory nuts, though difficult to shell, make excellent milk-simply crack between rocks, remove large shell fragments, grind the nutmeat with whatever adheres to it, soak overnight in cold water, then strain through cloth. Plant milks can be fermented like dairy milk. Soymilk fermented with yogurt cultures most closely resembles dairy yogurt.
Chapter 9
Fermenting Grains and Starchy Tubers
Grains and starchy tubers constitute the foundation of human nutrition worldwide, providing essential sustenance complemented by other food sources. The Food and Agriculture Organization (FAO) identifies the primary cereal grains as corn, wheat, rice, barley, sorghum, millet, oats, and rye, while the principal starchy tubers include potatoes, cassava, sweet potatoes, yams, and taro. The development of grain agriculture was instrumental in establishing early civilizations, as the stable storage properties of grains enabled economic development and societal organization.
These staple foods present digestive challenges in their natural state. They contain enzyme inhibitors and mineral-binding compounds that can limit nutrient absorption. Fermentation processes transform these compounds, enhancing nutritional benefits and digestibility. This biological transformation is particularly significant for cassava, where fermentation helps reduce naturally occurring compounds that could otherwise be problematic.
Traditional fermentation practices show remarkable consistency across diverse cultures. The process typically involves hydrating the ingredients, often combined with mechanical processing. Many cultures practice grain sprouting (malting) before fermentation to convert complex carbohydrates into simpler forms. Alternative methods include controlled microbial cultivation or traditional enzymatic processes.
The fundamental fermentation method begins with hydration, which activates both the grain's natural processes and beneficial microorganisms. When grains contact pure water, their surface microbiota become active while the seed begins its natural development. The process requires a minimum hydration period, with optimal results typically achieved between 8-12 hours.
Traditional grain preparations began with simple porridges and gruels, predating bread-making. These preparations vary in consistency from liquid to semi-solid forms, consumed according to cultural preferences. Fermentation enhances their nutritional profile and palatability. These fundamental preparations remain culturally significant comfort foods, often serving as traditional first foods for infants transitioning to solid nutrition.
Poi, a significant Hawaiian cultural food, consists of fermented taro root processed into a distinctive paste. The preparation requires thorough cooking of the taro root to transform its natural crystalline compounds. After thermal processing, the exterior is removed and the interior is mechanically processed into a smooth consistency using traditional or modern methods. The mixture then undergoes room temperature fermentation in appropriate vessels that accommodate natural expansion.
Sourdough cultures exemplify living fermentation systems that evolve with their environment. While various methods exist for initiating sourdough cultures - including using natural starch waters, fruit derivatives, cultured dairy products, or commercial starters - the basic combination of flour and water suffices due to naturally present beneficial microorganisms. The process requires regular aeration to distribute microbial activity and maintain optimal conditions for fermentation while preventing unwanted growth.
Chapter 10
Conclusion: A Cultural Revivalist Manifesto
We must reclaim our food. Food embodies a complex web of relationships, forming the context of our existence. Today's supermarket shelves showcase products of a globalized system built on proprietary genetics, synthetic chemicals, monocultures, long-distance transportation, factory processing, wasteful packaging, and energy-intensive refrigeration. This system destroys the earth, our health, economic vitality, and robs us of dignity by breeding dependency.
We need to cultivate different relationships instead. With plants and animals, we must reconnect to our food sources by growing, gleaning, foraging, and respecting the life that sustains us. With farmers and producers, we should buy local food, support small-scale processing, and perhaps find our own niche in food creation.
We must honor our ancestors by remembering, rediscovering, and reclaiming their cultural legacies, including seeds and fermentation processes. We should embrace mysteries, acknowledging that despite scientific advances, much remains unknown about the microscopic world and our own bodies.
Community is essential-self-sufficiency is a dangerous myth. We need to share food, encourage others' production activities, and do the hard work of finding common ground despite varied visions. Our individual awareness must build into social movements addressing food justice, indigenous rights, and environmental impact.
Finally, we must maximize the use of abundant, low-impact, reusable materials, interrupting the disposable society through DIY culture. By engaging life forces through practices like fermentation, we consciously cultivate this web of relationships, practicing cultural revival and reconnecting with our context.
