Independent buying guides for home fermentation

Home Fermentation Glossary: 24 Terms Explained

The words that show up in home fermentation specs, reviews and how-to guides, explained without jargon. Open any term for the full explanation and what to look for when buying.

Airlock lid
A lid fitted with a one-way valve that lets fermentation gases escape while keeping air and insects out.
Read more about airlock lidRelated: Best Airlock Lids
Anaerobic fermentation
Fermentation that happens in the absence of oxygen, the condition most vegetable and some dairy ferments rely on.
Read more about anaerobic fermentation
Backslopping
Using a small amount of a finished ferment to start the next batch, a traditional way to keep a culture going.
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Brine
Salt dissolved in water used to submerge vegetables during fermentation, with strength measured as a percentage of weight.
Read more about brineRelated: Best Salts for Fermenting Vegetables
Continuous brew
A kombucha brewing method that draws off finished tea from a large vessel while continually adding fresh sweet tea.
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Dry salting
Mixing salt directly into shredded or chopped vegetables so they release their own brine, as with classic sauerkraut.
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Fermentation weight
A glass, ceramic, or silicone weight placed on top of vegetables to keep them submerged below the brine line.
Read more about fermentation weightRelated: Best Fermentation Weights
Headspace
The empty gap left between the top of a ferment and the lid, sized to allow for bubbling and gas buildup.
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Iodized salt
Table salt with added iodine and often anti-caking agents, generally avoided by fermenters for clarity and texture.
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Kahm yeast
A harmless but unappetizing white film that can form on brine surfaces, distinct from colored, fuzzy mold.
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Koji
Rice, barley, or soybeans inoculated with a specific mold used to start miso, soy sauce, and other Japanese ferments.
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Lacto-fermentation
Fermentation driven by lactic acid bacteria that preserves vegetables and gives sauerkraut and kimchi their tang.
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Milk kefir
A tangy, pourable fermented milk drink made by culturing milk with milk kefir grains.
Read more about milk kefirRelated: Best Milk Kefir Grains for Home Brewing
Natto
Fermented soybeans made with a specific bacterial culture, known for a sticky, stringy texture and strong aroma.
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Onggi
A traditional Korean earthenware crock, valued for kimchi and other ferments for its breathable, porous walls.
Read more about onggiRelated: Best Onggi Crocks
pH
A numeric scale measuring acidity, used by fermenters as one indicator of how far a ferment has progressed.
Read more about phRelated: The Best pH Meters for Fermentation
Salt percentage
The weight of salt relative to vegetable or brine weight, used to control fermentation speed and safety margins.
Read more about salt percentageRelated: The Best Kitchen Scales for Fermentation
SCOBY
Symbiotic culture of bacteria and yeast used to ferment sweet tea into kombucha, often called the kombucha mother.
Read more about scobyRelated: Best SCOBY Starter Kits
Second fermentation
A sealed bottling stage for kombucha or water kefir that builds carbonation and lets in added flavors.
Read more about second fermentationRelated: The Best Swing Top Bottles for Kombucha and Fermented Drinks
Starter culture
A small amount of live bacteria or yeast, such as sourdough starter or yogurt culture, used to begin a new ferment.
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Tannins
Naturally occurring compounds, often added via grape or tea leaves, that many fermenters use to help keep pickles crisp.
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Tempeh
Fermented, pressed soybeans bound into a firm cake by a specific mold, commonly used as a meat alternative.
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Water kefir
A lightly fizzy, dairy-free fermented drink made by culturing sugar water with water kefir grains.
Read more about water kefirRelated: Best Water Kefir Kits
Whey
The thin, yellowish liquid that separates from curds in fermented dairy, sometimes reused as a starter for other ferments.
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