How to Make Milk Kefir: My Step-by-Step Guide
Milk kefir fermenting on the counter
Milk kefir has been a daily staple in my kitchen for years. This tangy, probiotic-rich drink is incredibly easy to make and has countless health benefits for your gut and beyond. Today, I’m sharing exactly how I make milk kefir, plus some tips and ideas to help you incorporate it into your daily routine!
Why Milk Kefir?
Milk kefir is a naturally fermented drink made by culturing milk with kefir “grains”—a unique combination of bacteria and yeasts that create a living ecosystem in your jar. The end result is a creamy, slightly fizzy drink loaded with probiotics, beneficial acids, and vitamins.
Raw vs. Pasteurized Milk
I personally use raw milk to make my kefir because it’s full of natural enzymes and nutrients that haven’t been destroyed by heat. Raw milk can make a gentler, more enzyme-rich kefir that some people find easier to digest. However, pasteurized milk works perfectly fine too! The kefir grains will do their magic no matter which milk you use.
What You Need
Milk kefir grains (about ½ tablespoon per cup of milk—this is a flexible guideline)
Raw or pasteurized milk
A clean glass jar
A coffee filter or breathable cloth
A metal ring or rubber band
A strainer and coffee filter (optional for straining)
How I Make Milk Kefir
1️⃣ Combine the milk and grains
In a clean glass jar, add about ½ tablespoon of kefir grains for each cup of milk. (Some days I use a little more, some days a little less—it’s very forgiving!)
Pour the milk over the grains, leaving some room at the top.
2️⃣ Cover and ferment
Cover the jar with a coffee filter and secure it with a metal ring or rubber band.
Leave it to ferment on your counter at room temperature for about 24-48 hours, depending on your desired level of tang. (Warmer kitchens will ferment faster, so check the texture and flavor to find your sweet spot!) The longer you ferment, the more probiotic content you’ll have in the finished product up to about 48-72 hours. Over-fermenting will result in the amount of probiotics starting to decrease some.
3️⃣ Refrigerate or strain
After about 24-48 hours, your kefir should be ready! Use a strainer to filter out the kefir grains. I slowly mix the kefir in the strainer over a bowl to help it filter through. Simply refrigerate the strained kefir it until you’re ready to drink, and add the kefir grains to another glass jar with milk to begin another batch, or keep reading for ways to store them.
4️⃣ Optional - Separate the milk solids and whey
Milk solids filtering from the whey
After filtering out the kefir grains, you can strain the kefir by placing a coffee filter in a strainer over a measuring cup. Let it sit in the fridge 8-24 hours to separate into thicker milk solids and whey. The longer you let it sit, the thicker the solids will become more greek yogurt-like consistency). You won’t really have any more whey filter out after the 24 hour mark though.
The milk solids stay in the coffee filter and can be sweetened and eaten like a yogurt (my family calls this “kefir yogurt”!).
The whey gathers in the measuring cup and can be used to start vegetable ferments, added to smoothies, or swapped in for milk/buttermilk in baking. It will store for weeks in the fridge!
The separated solids from the whey
What to Do with Extra Grains
Kefir grains multiply over time! Here’s what you can do with the extras:
Discard them if they’re causing your kefir to ferment too quickly.
Dry and store: Spread them out on a paper towel and let them dry on the counter until completely dry, then store in the freezer for later.
Store in milk: Place them in fresh milk and refrigerate for up to a week before starting another batch. If you want to store them longer, just refresh the milk weekly to keep them healthy!
How to Rehydrate Kefir Grains
If you’re using dried kefir grains from storage:
Place them in fresh milk at room temperature.
Change the milk every 24 hours until the grains become plump and begin to culture the milk (this may take a few days).
Once they’re actively fermenting, you’re good to go!
Ways to Enjoy Milk Kefir
Plain (it’s tangy and creamy!)
Sweetened with honey, maple syrup, or your sweetener of choice
As “kefir yogurt” by straining the kefir and eating the thickened milk solids
In smoothies or protein shakes for a probiotic boost
Smoothie popsicles using popsicle molds (my kids’ favorite!)
In baked goods: Use it in pancakes, waffles, muffins, or anywhere you’d use milk or buttermilk
Kefir popsicle - my kids’ favorite!
Final Thoughts
Fermenting your own milk kefir is an empowering, gut-friendly habit that’s simple and rewarding. Whether you’re looking to boost digestion, support your immune system, or simply try something new, I hope this guide gives you the confidence to get started!
If you have any questions, feel free to email me—I’m always happy to help fellow fermenters!
P.S. I’m so excited to announce that we’ll be hosting our first fermenting class this month! We’ll cover how to ferment pickles, kombucha, water kefir, and milk kefir, with lots of taste testing and tips to help you feel confident getting started at home. If you’re local and want to join, you can sign up here. I’d love to see you there!
And don’t forget to subscribe below for updates and future classes!