Use kefir with confidence
Milk kefir
A practical guide to grains, milk, fermentation time, straining, storage, and everyday use.
What milk kefir is
Milk kefir is milk fermented by kefir grains, a mixed culture of bacteria and yeasts.
Your first batch
Use clean equipment, a simple grain-to-milk ratio, and observe taste and separation instead of relying on the clock alone.
Care and storage
Regular feeding keeps grains active. Refrigeration slows fermentation when you need a short break.
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Guides built around real questions
Fermentation research
Does grain size matter?
Understand the study and the variables that matter in your jar.
Read the guide