Fermentation · Guide

What Can You Ferment? A Guide to Fermentable Foods

A category-by-category guide to everything you can ferment at home, covering vegetables, fruits, dairy, grains, honey, tea, coffee, beans, meat, fish, and sugary liquids. Includes starting points, what to watch out for, and what fermentation does to each category.

Read the guide Guides hub
Vegetables, grains and beans beside homemade fermented foods

Updated Oct 2026 · 4 min read

The short answer is: you can ferment almost anything. Vegetables, fruits, dairy, grains, beans, honey, tea, coffee, meat, and fish all undergo fermentation in food traditions around the world. Some ferments are as simple as adding salt to shredded cabbage. Others, like miso or salami, involve specialty cultures and months of patience. This guide walks through each category of fermentable food, explains what fermentation does to it, gives you practical starting points, and flags what to watch out for.

Vegetables

Vegetables are the most beginner-friendly category for fermentation. Lacto-fermentation, the process of using salt to create conditions where Lactobacillus bacteria thrive, works on virtually any firm vegetable. The bacteria convert natural sugars into lactic acid, producing that characteristic sour tang.

Best vegetables for fermenting Cabbage, carrots, radishes, green beans, garlic, onions, beets, cauliflower, peppers (hot and sweet), cucumbers, turnips, kohlrabi, and celery all ferment well. These vegetables are firm, have moderate sugar content, and hold up structurally during the fermentation process.
Vegetables that need more care Leafy greens (spinach, lettuce, kale) ferment quickly but break down into soft, unappealing textures. Tomatoes are high in water and can turn mushy, though they work in fermented salsas when diced. Zucchini and summer squash have high water content and tend to get slimy. These are not impossible to ferment, but they require shorter fermentation times and more attention.
Vegetables to avoid Ordinary potatoes need a dedicated method; do not substitute them into a carrot brine. Sweet potatoes have a separate dry-salted recipe linked below. Eggplant can develop bitter compounds during fermentation. Avocados have too much fat and too little sugar for lacto-fermentation. Frozen vegetables do not ferment well because freezing damages cell walls and produces a soft, watery texture.
What fermentation does to vegetables Lactic acid bacteria break down sugars and produce lactic acid, which lowers the pH and creates a tangy, sour flavor. The process also generates vitamins (especially B vitamins), increases mineral bioavailability by breaking down phytic acid, and populates the food with billions of live probiotic organisms. Texture stays crunchy when salt levels, temperature, and timing are managed properly.
Where to start Sauerkraut (shredded cabbage plus 2% salt) or fermented carrot sticks in a 3-4% salt brine. Both are nearly foolproof.
2-3% salt by weight for dry-salted vegetables
3-5% brine concentration for submerged vegetables
18-22°C ideal fermentation temperature (64-72°F)
3-21 days typical fermentation window

For every vegetable with a link to its own method, see the fermented vegetables A–Z; for a ranked shortlist, see the best vegetables to ferment.

For the full spicy method, see fermented sweet potatoes with ginger. For fruit recipes, see apricots, raspberry preserves, bananas and preserved lemons.

Fruits

Fruits ferment fast due to their high sugar content. Wild yeast on fruit skins kicks off fermentation readily, converting sugars into alcohol, CO2, and flavor compounds. Fruit fermentation can go in two directions: a short lacto-ferment that preserves the fruit with a tangy fizz, or a longer alcoholic fermentation that produces wine, cider, or mead.

Lacto-fermented fruit Stone fruits (plums, peaches, cherries), berries, and citrus segments can be lacto-fermented in a light salt brine (1-2%) or with a splash of whey. Ferment for 2-5 days at room temperature. The result is a tangy, probiotic fruit that works as a topping, dessert component, or snack. Keep fermentation short to prevent excessive alcohol production.
Fruit wines and ciders Grapes, apples, pears, and most high-sugar fruits produce wine or cider when fermented with yeast for 1-4 weeks. This is alcoholic fermentation. Wild yeast on the fruit skins can do the work, or you can add a commercial wine yeast for more predictable results.
Fruit ferments to try Tepache (fermented pineapple rinds with piloncillo and cinnamon) is a classic entry point. Fermented salsa (tomatoes, peppers, onions with 2% salt) is technically a fruit ferment. Preserved lemons (whole lemons packed in salt for 3-4 weeks) are a North African staple that adds deep umami to cooking.

Watch for

  • Fruit ferments attract fruit flies. Cover with a tightly woven cloth, not cheesecloth.
  • Fruits with high sugar can develop alcohol content if fermented too long. If you want a probiotic fruit rather than a boozy one, keep fermentation to 2-3 days and refrigerate.

Dairy

Dairy is one of the oldest categories of fermented food. Cultures around the world developed yogurt, kefir, cheese, sour cream, and buttermilk long before refrigeration existed. Fermenting milk extends its shelf life, increases digestibility (especially for people with mild lactose sensitivity), and creates new flavors and textures.

What fermentation does to dairy Lactic acid bacteria (Lactobacillus, Streptococcus thermophilus, Lactococcus) convert lactose (milk sugar) into lactic acid. This thickens the milk, lowers the pH, and produces the characteristic tang of yogurt and sour cream. People with lactose intolerance often tolerate fermented dairy better because much of the lactose has already been broken down.
Easy starting points Yogurt is the simplest dairy ferment. Heat milk to 82°C (180°F), cool to 43°C (110°F), stir in a few tablespoons of store-bought plain yogurt as starter, and hold at 40-46°C (104-115°F) for 6-12 hours. Kefir is even simpler: add kefir grains to room-temperature milk and wait 12-24 hours.
Beyond yogurt Cultured butter (cream fermented with mesophilic culture, then churned) has a richer, more complex flavor than sweet cream butter. Labneh (yogurt strained until thick like cream cheese) is a Middle Eastern staple. Creme fraiche is cream fermented with buttermilk culture for 12-24 hours. All of these use the same basic principle of adding a bacterial culture to dairy and holding at the right temperature.

Grains and flour

Fermenting grains breaks down gluten and phytic acid, makes nutrients more available, develops complex flavors, and can produce natural leavening. Many traditional breads and porridges around the world rely on fermentation rather than commercial yeast.

Sourdough The most familiar grain ferment. A sourdough starter is a mixture of flour and water colonized by wild yeast and Lactobacillus. It leavens bread and produces the sour flavor. Building a starter takes 5-7 days of daily flour-and-water feedings. Once active, it lasts indefinitely with regular feeding.
Injera A spongy, tangy flatbread from Ethiopia and Eritrea. Teff flour is mixed with water and fermented for 2-3 days until bubbly and sour. The batter is poured thin and cooked like a crepe. The fermentation creates the signature spongy texture and sour flavor.
Dosa and idli South Indian fermented crepes (dosa) and steamed cakes (idli) are made from a batter of soaked rice and urad dal (split black lentils) ground together and fermented overnight. The wild fermentation produces CO2 that makes the batter light and airy.
Kvass and rejuvelac Bread kvass ferments stale rye bread in sweetened water for 12-24 hours. Rejuvelac ferments sprouted wheat or rye berries in plain water for 2-3 days. Both are probiotic grain beverages with a tart, lemony flavor.
Fermented porridge Ogi (West Africa) and pozol (Mexico) are traditional fermented grain porridges. Ogi is made from fermented maize. Pozol is made from nixtamalized corn dough fermented for several days. Both are souring processes that preserve the grain and develop a tangy, complex flavor.
Where to start A sourdough starter. Mix equal parts flour and water, feed daily for a week, and you have a living culture that can leaven bread for years.

Honey: distinguish mead from fresh ingredients in a jar

Honey can be an ingredient in a fermentation recipe, but a honey-and-water mead and fresh garlic submerged in honey are different preparations. Do not transfer a culture, timetable or storage claim between them.

Mead A specified honey-and-water mixture fermented with yeast has its own gravity, nutrition, temperature and packaging decisions. Start with the mead guides and a complete recipe.
Garlic and peppers in honey The Extension guidance reviewed for our honey-ferment article advises against garlic-in-honey fermentation and reports no science-based recipe for peppers in honey. Raw honey, turning the jar or a spoonful of vinegar does not resolve that gap.
Ginger and other fresh additions A new ingredient does not inherit a validated method from garlic. For flavor without a preservation project, prepare a small serving mixture for the current meal rather than a jar to leave on the counter.

For a published condiment formula that includes honey as one measured ingredient, see cultured ketchup. Its complete formulation is different from fresh vegetables covered in honey; neither is a generic method for the other.

Tea and coffee

Both tea and coffee have deep connections to fermentation. Kombucha is the most well-known tea ferment, but fermentation also plays a role in the production of certain tea varieties. Coffee cherries undergo fermentation during processing, and that fermentation stage affects the flavor of the roasted beans.

Kombucha and jun Kombucha ferments sweetened black tea with a SCOBY for 7-14 days. Jun uses green tea and raw honey with its own culture, fermenting for 5-7 days. Both produce tangy, carbonated probiotic drinks. These are the most common tea ferments for home production.
Pu-erh and other post-fermented teas Pu-erh tea from Yunnan, China undergoes microbial fermentation after the leaves are dried. Sheng (raw) pu-erh ages slowly over years or decades. Shou (ripe) pu-erh is fermented in a humid pile for 45-60 days to accelerate the aging process. The fermentation develops earthy, smooth, and complex flavors that improve over time.
Coffee fermentation Most specialty coffee undergoes controlled fermentation during processing. In washed processing, the coffee cherries are pulped and the mucilage (sticky fruit layer) is fermented in water for 12-72 hours before washing. In natural processing, the whole cherries ferment as they dry. Some producers now use anaerobic fermentation in sealed tanks to develop specific flavor profiles. You are unlikely to ferment coffee at home, but understanding this process helps you appreciate how fermentation shapes coffee flavor.

Beans and legumes

Beans and legumes are protein-rich foods that benefit greatly from fermentation. The process breaks down anti-nutrients like phytic acid and lectins, reduces compounds that cause gas, and transforms the beans into entirely new products with different textures and flavors.

Tempeh Cooked soybeans inoculated with Rhizopus oligosporus mold spores and incubated at 30-32°C (86-90°F) for 24-48 hours. The mold binds the beans into a firm, sliceable cake. Tempeh can also be made from chickpeas, black beans, lentils, or a mix of beans and grains.
Miso Soybeans mixed with salt and koji (grain inoculated with Aspergillus oryzae) and fermented for 3-12 months. Miso is one of the most flavor-dense condiments, packed with umami. Chickpea miso, barley miso, and adzuki bean miso are all possible variations.
Natto A Japanese ferment where cooked soybeans are inoculated with Bacillus subtilis and incubated at 38-45°C (100-113°F) for 22-24 hours. Natto is famous for its sticky, stringy texture and strong, pungent flavor. It is rich in vitamin K2 and the enzyme nattokinase.
Fermented bean paste (doenjang, doubanjiang) Korean doenjang and Chinese doubanjiang are thick, savory pastes made from fermented soybeans or broad beans. They ferment for months and develop intense umami flavor. These are used as the base for soups, stews, stir-fries, and marinades.
Dosa and idli batter South Indian dosa batter (ground rice and urad dal fermented overnight) is a legume ferment that uses wild Lactobacillus. The fermentation produces CO2 that lightens the batter and creates lactic acid that gives dosa its subtle tang.
Where to start If you can source tempeh starter, making tempeh from any cooked bean is a rewarding 48-hour project. Fermenting dosa batter requires no starter at all, just soaked rice and urad dal blended together and left at room temperature overnight.

Step-by-step methods for each are in the Koji, Miso & Soy guides: how to make tempeh, how to make miso, how to make natto and how to make koji.

Meat and fish

Meat and fish fermentation is the most advanced category and requires the most care. Unlike vegetable and dairy ferments, which operate in high-acid or high-salt environments that naturally suppress pathogens, meat and fish ferments carry higher safety risks if done incorrectly. That said, fermented meat and fish products have been made safely for thousands of years across many cultures.

What fermentation does to meat and fish Lactic acid bacteria lower the pH of the meat, inhibiting pathogenic bacteria. Salt draws out moisture and further creates hostile conditions for spoilage organisms. In cured meats like salami, fermentation develops the tangy flavor and firm texture while the drying process concentrates the flavors and extends shelf life.
Familiar examples Salami and other fermented sausages use a combination of salt, curing agents (sodium nitrite/nitrate), and bacterial starter cultures. Gravlax is salmon cured in salt, sugar, and dill for 2-3 days. Fish sauce is whole fish layered with salt and fermented for 6-24 months until liquefied. Surstroemming (Swedish fermented herring) and garum (ancient Roman fish sauce) are extreme examples of long fish fermentation.
Corned beef and pastrami Traditional corned beef involves curing beef brisket in a salt brine with spices for 5-10 days. While primarily a curing process, some lactic acid fermentation occurs during the brining period, contributing to the flavor. Pastrami adds smoking and spice rubbing to the cured meat.

Watch for

  • Never attempt to ferment raw poultry at home. The risk of Salmonella and Clostridium is too high without commercial-grade controls.
  • Meat fermentation requires curing salt (sodium nitrite, also called Prague powder #1 or Instacure #1) to prevent botulism. Regular salt alone is not sufficient for safe meat fermentation.
  • Maintain strict temperature control during meat fermentation. The fermentation stage for sausage typically needs to stay at 20-25°C (68-77°F) for 24-72 hours before moving to a cooler drying environment.
  • Start with well-documented recipes from reputable sources. Meat fermentation is not the place to improvise. Follow salt, curing agent, and temperature guidelines precisely.
  • Fish sauce and similar long-fermented fish products are safe because of extremely high salt concentrations (typically 20-25% salt by weight). Do not reduce the salt in these recipes.

Sugary liquids

Any liquid containing sugar can be fermented. This is the broadest and most open-ended category. Fruit juice, sugar water, coconut water, maple sap, agave nectar diluted in water, and even plain soda can serve as the base for a fermented drink.

Fruit juice Apple juice becomes hard cider. Grape juice becomes wine. Any fruit juice becomes a fermented beverage when yeast is present (either wild or added). A simple wild-fermented soda can be made by adding a ginger bug or water kefir grains to fruit juice and fermenting for 1-3 days.
Sugar water Water kefir grains ferment plain sugar water into a mild, probiotic soda in 24-48 hours. The sugar provides food for the bacteria and yeast. You can flavor the second fermentation with fruit juice, herbs, or spices.
Coconut water Coconut water ferments well with water kefir grains or a ginger bug. It naturally contains minerals and electrolytes that support the fermentation cultures. The result is a slightly sour, fizzy tropical drink.
Tree saps Maple sap, birch sap, and palm sap all ferment into mildly alcoholic beverages. Palm wine (toddy) is a traditional fermented drink across tropical regions of Asia and Africa. These saps are low in sugar compared to their syrup or concentrated forms, so they ferment into light, sessionable drinks rather than strong wines.
What to watch out for Any sugary ferment can produce alcohol. The longer you ferment and the more sugar you start with, the higher the alcohol content. If you want a probiotic soda rather than an alcoholic beverage, keep fermentation short (1-3 days), use moderate sugar levels, and refrigerate promptly to slow fermentation.

For naturally fizzy sodas such as ginger beer, tepache, kvass and fermented lemonade, see the Fermented Sodas guides, starting with the ginger bug. Take any of these alcoholic ferments one step further and acetic acid bacteria turn them into vinegar: see the Vinegar guides and how to make apple cider vinegar. For cider itself, see how to make hard cider.

Where to start

The best way to learn fermentation is to pick one project and do it. Do not try to master every category at once. Start with something simple, learn how salt, temperature, and time interact, and build from there.

  1. 1
    Complete beginner Make sauerkraut or fermented carrot sticks. You need cabbage or carrots, salt, and a jar. The process teaches you the fundamentals of lacto-fermentation: salt ratios, keeping food submerged, judging doneness by taste, and recognizing healthy fermentation activity.
  2. 2
    Ready for more variety Try fermented pickles, kimchi, or a simple fermented hot sauce. These add brine calculations, spice combinations, and different vegetable textures to your experience. A brine calculator helps you nail the salt ratio.
  3. 3
    Comfortable with vegetables Move into yogurt, kefir, or a sourdough starter. Dairy and grain ferments introduce starter cultures and temperature control. Each one expands your toolkit and gives you a daily-use fermented product.
  4. 4
    Intermediate fermenter Try kombucha or tempeh using a complete method. These involve different cultures and process controls from vegetable ferments; do not treat fresh garlic or peppers in honey as interchangeable beginner projects.
  5. 5
    Advanced projects Miso, mead, fermented sausage, and fish sauce are long-term commitments (weeks to months). They reward patience with flavors you cannot buy. Approach meat and fish ferments with respect for food safety and follow established recipes precisely.
Universal rule Discard suspected spoilage without tasting it. Appearance and smell can reveal a problem but cannot prove safety; use the complete method and its required process checks.
Track your ferments Write down what you did: the weight of the produce, the amount of salt, the date you started, the room temperature, and when you refrigerated. These notes help you reproduce successes and troubleshoot failures. Fermentation is a living process, and small changes in conditions produce different results.

FAQ

Frequently asked questions

What is the easiest food to ferment at home?
Sauerkraut is the easiest starting point. You need only cabbage and salt. Shred the cabbage, mix with 2% salt by weight, massage until it releases liquid, pack into a jar, and wait 7-14 days. Fermented carrot sticks are a close second, requiring just carrots and a 3-4% salt brine.
What foods should you not ferment?
Avoid fermenting foods that are already spoiled or past their prime. Soft, overripe vegetables break down into mush during fermentation. Raw poultry should never be fermented at home due to the risk of Salmonella and Clostridium. Very starchy vegetables like potatoes can be unpredictable without experience. When in doubt, stick with firm, fresh produce and well-documented recipes.
Can you ferment frozen vegetables?
Frozen vegetables do not ferment well. The freezing process damages cell walls, causing the vegetables to become soft and watery when thawed. They will not produce the crunchy, firm texture you want from a lacto-fermented vegetable. Fresh produce gives the best results. If you must use frozen, expect a softer product.
Is it safe to ferment food at home?
Home fermentation has a strong safety record. The high-acid environment created by lacto-fermentation (pH below 4.6) prevents the growth of harmful bacteria like Clostridium botulinum. Salt further inhibits pathogens. Billions of people worldwide eat home-fermented foods daily. The main risks come from ignoring visible mold, using contaminated equipment, or attempting advanced ferments (meat, fish) without proper knowledge.
Does fermentation destroy nutrients?
Fermentation generally increases the bioavailability of nutrients rather than destroying them. It breaks down phytic acid in grains and legumes, making minerals like iron, zinc, and calcium more absorbable. Fermentation also produces B vitamins and vitamin K2. Some heat-sensitive vitamins (like vitamin C) decrease slightly during fermentation, but the overall nutritional profile of fermented foods is typically better than the raw starting material.
Ads.txt