Make it: nine fermentation methods
One tested home method for each ferment, with amounts, temperatures, times and the signs that it is ready. Every number links to its source.

Skim milk, a live culture and a cloth: how to culture and strain milk into a thick, skyr-style result, with temperatures, times and the yield to expect.
- You need
- Skim milk, live culture, cloth
- Incubate
- 6–10 hours at 42–46 °C
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Milk, a little live yogurt and a steady warm place: a tested home method with temperatures, times, starter amounts and the signs that it is ready.
- You need
- Milk, live yogurt or culture
- Incubate
- 6–10 hours at 42–46 °C
Read the methodFix a problem

Pasteurised milk, a mesophilic culture, a cool room and a cloth: how to sour milk overnight into a fresh curd and drain it into tvorog or quark.
- You need
- Milk, mesophilic culture, cloth
- Ferment
- About 12–16 hours at 20–30 °C
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Kefir grains, milk and a day at room temperature: how much grain to use, how long to ferment, how to strain and how to look after the grains.
- You need
- Kefir grains, pasteurised milk
- Ferment
- 18–24 hours at 18–29 °C
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Cabbage, salt and a weight: the tested home method for sauerkraut, with salt by weight, fermenting temperatures and times, and the signs that it is done.
- You need
- Cabbage, pickling salt, a weight
- Salt
- 2.25–2.5% of the cabbage weight
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Sweet tea, a SCOBY and starter liquid: the tested home kombucha recipe, with temperatures, timing, flavouring and the cautions that matter.
- You need
- Tea, sugar, SCOBY, starter liquid
- Ferment
- 7–10 days at 20–25 °C
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Flour, water, a jar and daily feeding: how to start a sourdough starter, tell when it is ready and keep it going.
- You need
- Flour, water, a jar
- Keep it at
- 21–28 °C (70–82 °F)
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Soak, cook, acidify, dry, inoculate and incubate: a careful home tempeh method, with the acidity and temperature that matter.
- You need
- Soybeans, tempeh starter, lactic acid
- Incubate
- 24–36 hours at 30 °C (86 °F)
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Wine or hard cider, a vinegar culture, air and warmth: how to make vinegar at home, how to finish it, and why homemade vinegar is not for canning.
- You need
- Wine or hard cider, vinegar culture
- Ferment
- About 3–4 weeks at 16–27 °C
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