Making Milk Kefir – First Forays


The Back Story

Milk kefir is the most amazing concoction. Seeing the process in action, the smells, the changes in consistency of the milk is really quite thrilling. There is plenty of information on the internet on varying styles and approaches to fermenting milk kefir. The Wondergut Website Resources Page has links to the main websites I have used.

Really though, it is about reading a little and then just tuning in to our own sense of smell and taste and having a go. I am learning as I go along – learning what suits my gut. There is a certain pioneering feeling that comes with taking basic advice but then working out what suits ME – it is quite liberating to be honest.

Milk kefir has a broader range of lactobacillus community in it than water kefir (30-50 strains rather than 10-15). It has less risk of exploding, because less carbon dioxide is produced and my experience so far, suggests that the improvements in my gut have come more from milk kefir than water kefir. It is a bit of an acquired taste though - it is like a sharp, fizzy yoghurt.

The grains are made of bacteria and yeasts and they digest the lactose in the milk, breed and populate the milk. If you are lactose intolerant, it is worth trying it, because the microbes pre-digest the lactose - often making it more digestible and better tolerated.  When you consume milk kefir, you are consuming beneficial lactobacillus bacteria. And it is an entirely natural community, not a few species manipulated in a lab. The microbial action in milk kefir is an anaerobic process, but the milk creates a sufficient barrier to air so you don’t need to worry about keeping the grains submerged. I do close the lid on my milk kefir kilner jars too – mainly to keep flies or other things finding their way in there.



A plastic sieve.

A few differing sizes of Kilner jars – I am doing my first ferment in a 500ml Kilner because that holds enough to make my daily intake of milk kefir. I also use 500ml ones for the second ferment and to store in the fridge although, at the moment, I am making it and drinking it daily so it isn’t stored in the fridge for long. What you need in terms of jars will depend on the amount you intend to consume. My kids have yet to appreciate the wonder that is milk kefir so, at present, I am the only one imbibing it (although, I do hide it in their smoothies sometimes). And my brother steals some when he visits. I need more than one Kilner jar because as I strain the first batch, I am reloading a fresh kilner for the next batch.

Milk – ideally organic whole milk.

Milk Kefir grains – communities of bacteria and yeast.

A wooden spoon for helping to strain off the kefir from the grains – some websites suggest not using any metal with kefir (due to the lactic acid given off in the fermenting process and its possible interaction with metal.) I am not sure whether this really matters in terms of brief contact (I have metal cup measures) but I wouldn’t store the kefir or ferment it in metal containers.

Cup measures.

The Variables Involved In Fermenting Milk Kefir

Temperature – the warmer it is, the faster they will ferment.

Time – the longer I leave the brew, the more I will see the curd (thick creamy bit of milk) separating from the whey (the watery bit) and it all going more and more lumpy. This is because the longer I leave it, the more lactose (milk sugar) the grains digest. If left too long, they will eventually run out of their food supply, which is not good for them. My aim is to keep the time variable constant. I alter the other variables to ensure each batch is ready in a 24 hour period to provide me with fresh milk kefir daily.

Amount of milk – obviously the proportion of milk to grains is a factor and after my first batch, because things had been a bit slow going, I used 1 cup of milk and half a cup of the batch of kefir I had just made. This helped the grains along a bit because it added back in more lactobacillus bacteria from the batch I had just made.

Amount of grains – these grow gradually over time so watch out for that –1 tbsp to start with will grow and unless you split the extra off, your milk will start turning to kefir more and more quickly unless, of course, you add more milk. And then you will have more kefir to drink…..

If things don’t quite work out and I can’t see the milk taking on a life of its own within the 24 hr period, then the chances are one of my variables needs tweaking.


Other Factors

Oxygen - the microbial action in milk kefir is an anaerobic process, but the milk creates a sufficient barrier to air so you don’t need to worry about keeping the grains submerged. I do close the lid on my milk kefir kilner jars too – mainly to keep flies or other things finding their way in there.

Cleanliness - I am not obsessing about the cleanliness of utensils.  I either hand wash them in hot water or wash them in the dish washer.




1.5 cups of milk.
1 – 2 bulging tbsp. of milk kefir grains


Add together in a kilner jar.

Leave The Brew With The Lid Sealed – whilst both the milk and water kefir process involves the production of carbon dioxide, the rate at which the milk kefir does it is nothing like the rate the water kefir does. And, of course, the kilner allows for escape of gases to some extent via the rubber seal. Leaving the lid on the milk kefir doesn’t risk some sort of dirty home-made milk bomb experiment. Well not unless you forget about it and leave it for weeks on end and then you might get sprayed with milk kefir when you do finally open the lid.

Watch For Spooky Developments – Action seems to start from the top down and this highly attractive cottage cheese-like scab forms on the top of the milk pretty rapidly. The grains seem to work their way from the top down through the milk.

I Leave Mine For Around 24 hours – My combination of milk and grains at the temperature of my ferments cupboard in the dining room chez Wondergut means the milk kefir is ready within 24 hours. If the response is a bit slow, I will adjust one of the other variables.

Leave Somewhere Warm-ish And Ideally In View – 68 – 70 degrees F is the ideal (around 21 degrees C). The colder it is, the slower they will ferment and the hotter it is, the faster they will work. When starting out, keep them in view so that you don’t forget about it plus, it is really fascinating to watch. Look for it starting to turn lumpy and then for the curds to separate from the whey. When you open the Kilner, it should smell yeasty. Which isn’t a smell that goes hand in hand with the idea of great tasting food, I admit.

Often, when I have left it longer and the curds and whey have really separated, I fret that I have botched it and that this batch will be vile. But I sieve it anyway, remove the grains, lick the spoon and do you know what, despite the smell and the cottage cheesy look (I am selling it so well) there is this creamy fizziness to it that I love.

After 24 hrs Strain Off The Grains With A Plastic Sieve – The kefir (the thick milk minus the grains) should be nice and thick like yoghurt. My grains took a while to adjust and get into their groove so don’t get disheartened if your kefir starts off fizzy but a bit thin and watery. If your variables aren’t quite right and you haven’t seen any of the above occurring, then I would move it somewhere warmer and sit it out for a bit longer. For me, I adjust the milk and grain combination to ensure my cycle is a 24 hour one – you may have a different approach.

Repeat The Above Process With The 1-2 Heaped tbsp. Of Grains To Make The Next Batch – watch to keep the amount of grains consistent as they will grow over time.

With The Kefir I Have Made, I Like To Do A Second Ferment – I take the kefir I have made and put it into a half litre Kilner. I add a small amount of fruit – a couple of peelings of orange peel, a few strawberries or some banana (it is just a tiny taster compared to the volume of fruit I add to water kefir) and then leave it to ferment again. This time, the bacteria in the kefir use not only the lactose in the milk but also the sugar in the fruit. After a few hours (or quite a few if I forget it), I can see the curds and whey separating again. Then I hoik out the fruit (eat if edible) and drink the kefir or put it in the fridge for later.

I often forget the kefir at the fruit fermenting stage and end up leaving it overnight with the fruit in and then exclaiming when I spot it on the surface the next morning. Other than a bit of a whoosh when I open the lid, it is still very palatable and lovely and thick. I just remove the fruit, give it a stir and it is good to go – trust your own taste buds and sense of smell though – you will soon find out what suits your particular microbial make-up the best.

If I go away, I either take them with me or I just put the grains in a kilner of milk and leave in the fridge. The grains will continue working but at a MUCH slower pace.

It may sound complicated, but it really isn’t once you get going and, if you get into the swing of it, you will have a lifetime’s full supply of probiotics in a wonderfully natural form.

We are all individual – this is the basics of my practice, but this wonderful process is totally interactive and involves each of us working out what volume/rate/fermentation time/flavor best suits us and the environment in which we are doing it. That takes a bit of experimenting and it involves trusting our senses of taste and smell and adjusting our process to suit us.

This has been a really joyful experience for me and a number of gut symptoms from which I have suffered for some time have abated very rapidly. This is not one size fits all though – our gut microbiome is as unique as our finger print so do trust yourself as to what level of fermentation suits you. And for some of us, it may not suit at all.

There is so much information online – enjoy falling into the internet black hole that is fermenting websites!! You will see that there are so many different ways to ferment milk kefir – enjoy finding your own.


Spreading straightforward information about the fundamental importance of a healthy gut microbiome.