How to make authentic milk kefir?

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How to Make Milk Kefir at Home (Step-by-Step Guide)

Making your own authentic milk kefir is surprisingly easy. With just two ingredients—milk and live kefir grains—you can brew a delicious, creamy probiotic drink right on your kitchen counter. Follow our simple guide below.

What You Need (The Checklist)

🥛 Ingredients:


  • Milk Kefir Grains (1 tsp approx.): Live, active grains are essential. Do not use a powdered starter.

  • Fresh Milk (250ml – 500ml): Whole, organic cow’s or goat’s milk works best. Avoid lactose-free or ultra-pasteurized (UHT) milk for the best results.

🥄 Equipment:


  • Glass Jar: A standard 0.5L to 1L jar.

  • Breathable Cover: A coffee filter, paper towel, or clean cloth secured with a rubber band. (Do not use an airtight lid during fermentation).

  • Plastic or Nylon Sieve: To strain the grains. Avoid metal if possible, although stainless steel is generally okay for brief contact.

  • Plastic or Wooden Spoon & Collection Bowl.

🛒

Need supplies? Get a complete Milk Kefir Starter Kit with fresh grains and all essential tools delivered to your door.

The 4-Step Brewing Process

1
Combine Grains & Milk

Place your milk kefir grains into your clean glass jar. Pour the fresh milk over them. A good starting ratio is about 1 teaspoon of grains per cup (250ml) of milk. Do not fill the jar completely; leave some headspace at the top.

2
Cover & Ferment

Cover the jar with your breathable cloth or coffee filter and secure it with a rubber band. This keeps fruit flies out while allowing gases to escape. Place the jar in a quiet spot out of direct sunlight at room temperature (ideally 20°C – 25°C / 68°F – 77°F).

Let it ferment for about 24 hours. Fermentation will be faster in summer and slower in winter.

3
Check & Harvest

How do you know it’s ready? Gently tilt the jar. The milk should be thickened to the consistency of drinkable yogurt. You may see small pockets of clear yellow liquid (whey) separating near the bottom—this is normal and means it’s definitely done!

Place your sieve over a clean bowl. Pour the entire contents of the jar into the sieve. Use your plastic spoon to gently stir the kefir through the sieve, leaving the grains behind.

4
Enjoy & Repeat

The thickened liquid in the bowl is your finished milk kefir! You can drink it straight, chill it, or blend it with fruit for a smoothie.

Take the grains trapped in the sieve and immediately place them back into your jar (no need to wash the jar every time). Add fresh milk, cover, and start the process all over again for tomorrow’s batch!

Pro Tip: Do not rinse your grains with water. This removes the protective beneficial bacteria layer. Just scoop them directly from the sieve back into fresh milk.

Watch the Process

How to make milk kefir on YouTube

Video: How to make milk kefir – YouTube

Milk Kefir FAQ: Common Questions

How do I take a vacation from kefir-making?
Place your grains in a fresh jar of milk, cover with a lid, and put it in the fridge. The cold significantly slows down fermentation. The grains will be fine for 1 to 2 weeks. When you return, strain the milk (it might be very sour) and start a fresh batch on the counter. The first batch back might take a little longer to wake up.
Why is there a yellow liquid layer (whey) separating?
This is perfectly normal! It means your kefir is “over-fermented”—the grains have consumed all the lactose. It’s safe to drink but will be very tart. To prevent this, shorten the fermentation time (harvest sooner) or use more milk for the amount of grains you have.
Why should I avoid metal?
Prolonged contact with certain reactive metals can harm the live culture over time due to the acidity of kefir. Using a stainless steel sieve for a few seconds of straining is generally fine, but avoid fermenting in a metal container or leaving a metal spoon sitting in the jar.
What are kefir grains exactly?
They are not cereal grains like wheat. They are a complex, symbiotic “SCOBY” (Symbiotic Culture Of Bacteria and Yeast) held together by a polysaccharide matrix called Kefiran, created by the bacteria. They look like small, rubbery cauliflower florets and are the living engine that ferments the milk.

Get Everything You Need to Start Today

Don’t have grains or the right tools? Get our complete Milk Kefir Starter Kit, delivered fresh to your door across Europe.


Buy milk kefir grains starter kit

The Kit Includes:

  • ✅ 10g Fresh, Live Milk Kefir Grains (guaranteed active)
  • ✅ Plastic Strainer set (safe for grains)
  • ✅ Fermentation Jar
  • ✅ Adhesive Thermometer Strip (to monitor temperature)
  • ✅ Detailed Instructions


🛒 Buy the Milk Kefir Starter Kit

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