ShelfLife
How long does kefir last?
Store-bought kefir keeps about 1 week in the fridge from the day you buy it. Once opened, FoodKeeper suggests finishing it within 1 to 2 days for the best quality. The USDA doesn't recommend freezing it.
| Food | Fridge | Freezer |
|---|---|---|
| Kefir | 1 weekfrom purchaseOpened: 1–2 days | Not recommended |
Fridge at 4 °C (40 °F) or colder, freezer at −18 °C (0 °F). Freezer times are for best quality: food kept frozen stays safe, but slowly loses taste and texture. These times are USDA guidance, not a guarantee. When in doubt, throw it out.
How to tell if kefir has gone bad
- Kefir is naturally sour and fizzy, so look for change: a harsh, rotten or yeasty-alcoholic smell.
- Mold on the surface or around the cap.
- Chunks that don't shake back in, or a pink, green or gray color.
How to store kefir
- Keep kefir at the back of the fridge with the cap tightly closed.
- Shake it before pouring: separation is normal.
- Kefir keeps fermenting slowly even in the fridge, so it gets more sour and fizzy over time; open the cap carefully.
Can you freeze kefir?
The USDA doesn't recommend it: the texture separates and the live cultures slow down. Frozen in ice cube trays, it can still be used in smoothies.
Questions
How long does kefir last once opened?
FoodKeeper suggests 1 to 2 days for the best quality. Many labels allow longer; follow the label and your nose.
Is fizzy kefir bad?
No. Fermentation produces a little carbon dioxide. Fizz together with a rotten smell or mold is a different matter.
How long does homemade kefir last?
Strained homemade kefir keeps a few days in the fridge in a sealed jar; it gets more sour each day.
Add kefir to ShelfLife when you open it.
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Storage times: USDA FoodKeeper (Food Safety and Inspection Service), public domain. Text by ShelfLife.