Milk kefir is a naturally fermented dairy drink made by adding live kefir grains — a mix of beneficial bacteria and yeasts — to milk. As the grains ferment the lactose, they create a tangy, probiotic-rich beverage that supports gut health, digestion, and immune function. Making kefir at home is simple, cost-effective, and reduces reliance on store-bought yoghurt or probiotic drinks, which often comes in single-use plastic packaging. By reusing glass jars and producing your own kefir daily, you can significantly cut down on plastic waste and food miles, making it not just a healthy choice — but a more sustainable one too.
Below is how you activate your dried milk kefir grains as well as how to make kefir using milk kefir grains. It will take around 3-5 batches to activate your dried milk kefir grains.
What you need
- Dried milk kefir grains
- 1/2 cups of milk
- 1 cup non-chlorinated water (filtered or spring water or you can used cooled boiled water too)
- Glass jar (around 500 ml)
- Muslin cloth
- Rubber band
- Sieve - fine meshed
- Bowl that fits the sieve
1. Rehydrate the Kefir Grains
- Pour the dehydrated kefir milk grains into a clean glass jar.
- Add 1 cup of non-chlorinated water.
- Stir gently, cover the jar with a muslin cloth and secure with a rubber band and let stand at room temperature for 2 hours.
2. Strain & Rinse
- Strain the mixture through a fine mesh sieve to collect the rehydrated kefir grains.
- Rinse the grains under warm water (ie body temperature) for about 10 seconds while they’re in the sieve.
- Place the grains back into the clean glass jar.
3. Add Milk & Ferment
- Add ½ cup of fresh milk (any dairy milk is fine).
- Stir gently with a clean spoon and cover the jar with a muslin cloth and secure with a rubber band and let stand for 24 hours between 19-25°C. Keep out of direct sunlight.
- Gently stir contents with a clean spoon after 8 hours.
4. Strain & Rinse
- After 24 hours, stir the contents with a clean spoon and strain the kefir grains through a sieve and then rinse the grains in warm water (ie body temperature). The strained liquid is milk kefir which is discarded for the first 3-5 batches until it develops a pleasant, clean sour taste and creamy consistency.
- Place the sieve in a bowl of warm water and lightly rub the grains between clean fingers.
- Once clean, you’re ready to start the next batch — repeat steps 3 to 4 until your kefir develops a pleasant, clean sour taste and creamy consistency — usually by the 3rd to 5th batch. Do not drink the milk kefir from the first 3 to 5 batches as the grains are stabilizing.
Important Notes
- Do not rinse grains daily forever — after the 7th batch, you can stop rinsing.
- Grains may sink at first, but as they activate, many will begin to float — this is normal and a sign of health.
- Once the kefir thickens quickly or separates into curds and whey before 24 hours, increase the milk to 1 cup per batch.
- As grains grow, you can either: increase the amount of milk, or remove a small amount of grains to prevent overcrowding.
- Signs of high activity are thick texture, curds floating in clear liquid (whey), or strong sour taste.
- Don’t use hot water to rinse or wash the kefir grains as they will die.
Maintaining the Right Grain-to-Milk Ratio
- A good general ratio is 1 part grains to 7–10 parts milk by volume. For example: ¼ cup grains to 2½ cups milk = 1:10).
- In hotter conditions, a 1:20 ratio is often better.
- Adjust to suit your taste and how quickly your kefir ferments.
- Mark the jar with a line to track how much culture to use. As grains grow, removing the excess above the line once a week and store or dry them as backup.
Temperature & Grain Care
- In colder climates or winter, fermentation slows down. To help fermented kefir in these conditions:
- move the jar to the warmest part of the house;
- wrap the jar in a tea towel, blanket or put in small insulated bag to help maintain warmth;
- Use a fermentation mat that is set to around 20-22C; or
- Reduce the amount of milk to grains to help to ferment faster.
- In hot climates or summer, fermentation happens faster. To avoid sour or over-fermented kefir:
- move the jar to a cooler area during the day; or
- place it in the fridge during the hottest hours, then bring it to room temperature overnight; or
- ferment inside a cooler box with a small ice pack.