Dairy

How to make Milk Kefir

A tangy, lightly fizzy cultured milk made by fermenting milk with kefir grains at room temperature. Expect a couple of minutes of work, about a day of fermenting, then a quick strain, with the grains carrying straight on to the next batch.

Quick answer

Add the kefir grains to fresh milk in a clean jar and cover it loosely. After 1 day, let the milk culture for about a day, then check that it has thickened and turned tangy. After 1 day, strain out the grains to start the next batch, then bottle and chill the kefir.

Difficulty
Beginner
Total time
1 day
Ingredients
2
Steps
3

Safety

  • • Move the strained grains straight into fresh milk to keep them alive, and do not rinse them in chlorinated tap water.
  • • Cover the jar with a cloth rather than a sealed lid so the kefir can off-gas.
  • • A tangy, yeasty smell is normal. Pink, orange, or fuzzy growth means the batch and grains should be discarded.
  • • Prefer nylon or plastic tools over metal for prolonged contact with the grains.

Step-by-step

Day 0

Step 1: Combine grains and milk

Add the kefir grains to fresh milk in a clean jar and cover it loosely.

  • Set up clean equipment Wash the jar, a non-metal sieve, and a spoon before you start.
  • Add grains to milk Put the grains in the jar, pour in the milk, and cover with a cloth.
Day 1

Step 2: Ferment and check

Let the milk culture for about a day, then check that it has thickened and turned tangy.

  • Ferment at room temperature Leave the jar undisturbed for 18-24 hours.
  • Check the set It is ready when the milk has thickened and smells pleasantly tangy.
Day 1

Step 3: Strain and store

Strain out the grains to start the next batch, then bottle and chill the kefir.

  • Strain out grains Pour the kefir through a non-metal sieve to catch the grains.
  • Bottle and refrigerate Bottle the strained kefir and refrigerate it, or flavour it with a short second ferment.

What to look for

  • • Day 0: The grains are suspended through the milk under a cloth cover. From here the grains slowly culture the milk into kefir.
  • • About 18-24 hours: The milk has thickened, smells tangy, and may show small pockets of clear whey. That is the sign the kefir is fermented and ready to strain.
  • • At straining: A taste is tangy and slightly fizzy, as sour as you like it. Strain earlier for a milder kefir or later for a sharper, tangier one.

Troubleshooting

  • The kefir is very sour and split into curds and whey. It fermented too long or the room was warm. Strain it earlier next time, give the jar a swirl partway through, or move it to a cooler spot.
  • The milk barely thickens. Too much milk for the amount of grains, or the room is cold. Use less milk per batch or a warmer spot, and give it a little more time.
  • The kefir turns slimy or stringy. The grains are stressed, often from temperature swings or neglect. Culture a few small batches in fresh milk at a steady room temperature to recover them.
  • The grains do not seem to grow. New grains can take a few weeks to settle in. Keep culturing batch after batch in fresh milk and they will gradually multiply.

Storage

Refrigerate the strained kefir, where it keeps for a week or two. To pause the grains, put them in a jar of fresh milk in the fridge and refresh the milk about weekly.

Shelf life: about 1-2 weeks refrigerated

Serving suggestions

  • • Drink it plain, or blend it into fruit smoothies.
  • • Use it in place of buttermilk in dressings, marinades, and baking.
  • • Pour it over granola or stir it into overnight oats.

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Frequently asked questions

What is Milk Kefir?

A tangy, lightly fizzy cultured milk made by fermenting milk with kefir grains at room temperature. Expect a couple of minutes of work, about a day of fermenting, then a quick strain, with the grains carrying straight on to the next batch.

How long does it take to make Milk Kefir?

Most batches of Milk Kefir are ready in about 1 day, though exact timing depends on temperature and how the ferment tastes along the way.

Is Milk Kefir hard to make?

Milk Kefir is a great beginner project — no special skills required, just clean equipment and a little patience.

What do you need to make Milk Kefir?

You'll need Milk kefir grains, Whole milk.

How do I know when Milk Kefir is ready?

Watch for these cues: Day 0: The grains are suspended through the milk under a cloth cover.; About 18-24 hours: The milk has thickened, smells tangy, and may show small pockets of clear whey.; At straining: A taste is tangy and slightly fizzy, as sour as you like it..

How do I store Milk Kefir?

Refrigerate the strained kefir, where it keeps for a week or two. To pause the grains, put them in a jar of fresh milk in the fridge and refresh the milk about weekly. Shelf life: about 1-2 weeks refrigerated.

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