Showing posts with label Ancient cultures. Show all posts
Showing posts with label Ancient cultures. Show all posts

Saturday, 15 August 2026

The Weird History of Milk Kefir: Ancient Myths, Scientific Mysteries, and the Woman Who Changed Kefir Forever

Depending on which website you read, milk kefir grains are said to have been either a gift from the Prophet Muhammad, food eaten by Abraham, impossible for scientists to recreate, or over 4,000 years old.  Surprisingly, much of this isn't supported by historical evidence.  The true story of kefir is even more fascinating and bizarre.  

Modern kefir has a surprisingly well-documented history dating to the North Caucasus and early twentieth-century Russia, while many of the much older stories are fascinating but poorly supported by historical evidence.  Some parts of kefir's history have been lost entirely.  Other parts can be pieced together from historical records, archaeology, and later evidence.  

In this article, I'll look at what archaeology, historical records, scientific research, and religious traditions actually tell us about kefir.  Some of the oldest and most often told stories that sound perfectly believable are surprisingly poorly supported, some of the newest discoveries are genuinely exciting, and one chapter in kefir's history is so bizarre it sounds like it was lifted straight from a fairy tale.  

milk kefir - has a fascinating history
Straining my milk kefir

The Extraordinary Story of How Kefir Reached Modern Russia

Evidence level: Strong

Remember the fairy tales/fables where something bad would happen, and everyone would lament if only someone could tell the Tsar then he would make everything alright?  Well, this is pretty much what happened with milk kefir.  

The first reliable references to kefir grains that can be traced to today come from Russia, and are surrounded by a true story that sounds like a fairy tale.  

Until the early 1900s, kefir wasn't produced in Central Russia, it was only occasionally brought from an area of the Caucasus in south west Russia, and sold in Moscow at a very high price.  Only the drink itself could be bought, and it was generally used as medicine.  At this time kefir was only for the rich, as common people could not afford the high price attached to this 'miracle drink'.

The first mention of Kefir in literature I can find is: 'Сиповичъ. Сообщеніе о кефирѣ въ протоколѣ засѣданія Кавказск. Мед. Общ. 1-го Іюля 1867 г'.  This roughly translates to: Sipovich. Report on kefir in the minutes of the meeting of the Caucasian Medical Society, July 1, 1867.  

Russian officials heard of the rumored health benefits of the nomadic Karachay people living around Mount Elbrus (in the Caucasus region), these stories combined with claims in the early literature mentioning the health benefits of kefir made it sound too good not to investigate further.  

Historical texts vary a bit here, most documents refer to milk kefir coming from the North Caucasus, and a number of references are made to Khurzuk and the Karachay communities near Mount Elbrus.  All of them agree on one point: the region where the earliest kefir history is documented was within Russia. 

To keep the people strong and healthy, the government wanted to obtain kefir grains and make kefir themselves.  Studies of the drink itself were always positive, but kefir can't be made without using grains.  To benefit the people and society as a whole, they hoped to make kefir themselves and eventually be able to make kefir available for average people.  

Around 1907 or 1908 the All Russian Physicians’ Society (the name of this society varies a bit, and may have been translated slightly wrong) requested Nikolay Ivanovich Balandov, who was head of the Moscow Dairy, to source milk kefir grains.  The story goes that Balandov tried to buy kefir grains, and was refused multiple times.  He knew his chances of getting anything were low, so he sent a woman named Irina Tikhonovna Sakharova.  

The idea was Irina would go with a team to the Caucasus, and she would charm a prince called Bek-Mirza Barcherov (I am not sure how to spell this name, or if he was even a 'prince', but he did rule over an aul) into giving her some kefir gains.  The prince was apparently quite taken by Irina, but there was strong tradition never to share kefir grains with outsiders, so he refused to give her any kefir grains.  Irina and her team eventually left to return home empty handed.  

On her way home, Irina and her companions were stopped by the prince's men, and Irina was kidnapped to become the prince's bride.  This 'kidnapping a bride' thing was common in that part of the world at the time.  

The rest of her party returned to Moscow, and petitioned the Tsar for Irina's release.  The Tsar intervened, ordered Irina's release, and demanded that she be offered adequate compensation.  This is where the story takes a twist.

Irina could have asked for money or gold, but instead asked for kefir grains.  Not wanting to contradict the Tsar and start a war, these demands were begrudgingly met.  As compensation for being kidnapped, Irina was given around 4.5 kg (10 pounds) of milk kefir grains.  

There is an alternate version of this story that is far less told, and far less romantic.  Shortly after arriving in Kislovodsk, Irina (accompanied by a factory manager) set out for a Karachay aul to visit 25 year old Prince Bek-Mirza Barcherov.  The prince supplied milk to the Balandov firm.  Barcherov was captivated by Irina’s beauty, and presented her with 10 pounds of kefir grains as a gift.  I don't know which version is true, but I can understand why this less incredible version would not be shared as widely across the internet.  

In both versions of this story, the milk kefir grains were then taken to the Moscow Dairy, and studied and multiplied and divided.  Production of milk kefir was ramped up rather quickly.  

The first milk kefir produced from these grains was given to patients at Botkin hospital.  Later it was sold through pharmacies as a health tonic.  

While kefir was intended to be made as a medicine, it was so simple to produce that it was then sold in shops and (after kefir grains found their way out of the dairy) started to be made in people's houses.  

By September 1908 the first bottles of milk kefir were sold in Moscow.  By the 1930s milk kefir was produced in large scale and was widely available across Russia.  

Milk kefir and modern Russia
Modern Russia has significant historical ties to milk kefir

Kefir in archaeology

Evidence level: Moderate

Researchers recovered ancient proteins and microbial DNA consistent with kefir-like fermentation from ~4,000 year old tombs of Tarim mummies.  This has sparked many over-hyped and over-simplified reports of the Chinese making the world's oldest cheese.  

The Tarim mummies were discovered in the territory of the Uyghur Autonomous Region, this is located in present-day Western China.  The story gets more interesting, as while this is in current day China the mummies are not 'Chinese' in the true sense of the word.  It has been determined that the mummies had blonde hair, a genetic trait that is remarkably uncommon/absent among genetically Chinese people.  

While the tombs sit within the borders of modern day China, in times past various Siberian people and other groups also inhabited in that area.  While the ancient tombs are located within the boundary of present-day China, the people in these tombs were genetically South Siberians.  

Current evidence suggests that the Tarim mummies had eaten something similar to kefir ie it had kefir proteins.  We don't know if they had kefir.  We don't know if the kefir of today descended from what was being consumed by the Tarim mummies, or if it was lost and the grains we use to make kefir today emerged some time later in history.    


Religious references to kefir

Evidence level: Weak

Kefir and the Bible 

Milk kefir is old, it has been around for a long time, and we don't know for sure when or how it was created.  While there are a few claims on the internet about milk kefir and the Bible, and there is a vague claim about milk kefir coming from Mohammad, it is unlikely that any of these claims are true. 

Some people claim that kefir is mentioned in the bible.  Most of these claims are highly improbable, though not entirely impossible.  The bible repeatedly mentions eating 'curds' which may possibly be referring to kefir, but it probably just means they were eating curds.  

Abraham lived to around 175 years old, which was not overly uncommon for people of that time.  The internet has a few pages that claim scrolls in Turkey exist which attribute Abraham's longevity to consuming kefir.  I am not sure that these scrolls ever existed.  Other than a few internet sites (which reference nothing), I can find no mention of these scrolls.  From Genesis 18:8 we learn that Abraham consumed milk curd, and it is safe to assume he likely consumed various types of fermented milk.  While it is not impossible he had kefir, it is extremely unlikely the kefir of today is descended from those grains.  Without finding huge numbers of references in historical literature, as well as strong religious traditions mentioning kefir, it is more likely that if kefir existed in Abraham's time, it later died out, and was recreated at a later date.  

I have read internet claims that Noah received kefir grains from God to help him and his family survive on the ark.  I find this claim to be highly unlikely at best.  I am yet to find any source of this claim other than web pages that don't reference anything other than other web sites also making this claim.    

Moses lived until about the age of 120.  Around 40 years of his life he was in the desert eating (among other things) manna.  There are some highly dubious claims online that manna was kefir grains.  Given that manna is described as tasting sweet, and kefir is best described as sour, this interpretation seems difficult to reconcile with the biblical description.  While we don't know for certain what manna was, it is likely that manna was actually secretions from scale insects.  

Even if fermented milk resembling kefir grains existed in biblical times, there is no evidence linking it directly to the heirloom kefir grains used today.  

Kefir and Islam

There are a few internet sites mentioning kefir grains as being a gift from Mohammad to his people and/or to Orthodox Christians.  Many of these internet claims say the grains were a gift from Mohammad to his people and to Orthodox Christians.

Kefir is not mentioned in Sunnah or Hadith, and kefir being a gift from Mohammad is not a universally held belief among Muslims, all of which immediately casts serious doubt upon this claim.  

Kefir is not a common traditional religious food of all Muslim people.  Many nomadic Muslims produce and consume various other types of fermented milk instead of kefir.  There is little evidence that kefir occupies a unique or honoured place across Islamic tradition today, which further weakens claims that it was universally regarded as a gift from Muhammad

It seems illogical that Mohammad would only give this gift to Orthodox Christians, and not to his own people as well.  Again this part of the story casts serious doubt on this claim.  

I am not certain, but don't think Mohammad travelled into the Caucasus mountains or any part of south west Russia (which is the location of the first modern historical references to milk kefir).  It would be more likely that if kefir grains came from Mohammad, they would have entered the world somewhere else, and spread from there.  

I also found IslamQA which states they "haven’t come across any authentic narrations citing the incident above".  While I don't know how reliable that site is, the response was prepared by Islamic scholars. 

For the above reasons, I find it highly unlikely that Mohammad giving the grains to his people or to Orthodox Christians could be the origin of kefir.  The only thing that gives this story any weak credibility is that milk kefir recently came from the Caucasus region, which is Muslim dominated and would have had Orthodox Christians in early years.  The part about Mohammad not travelling there makes this story difficult to reconcile with the historical evidence currently available.


Scientists can make kefir grains (but not the ones people use at home) 

Evidence level: Strong

Contrary to a common internet claim, scientists have successfully produced kefir grain-like microbial structures capable of fermenting milk.  They are not identical to the heirloom grains used today, but they demonstrate that kefir grains are not beyond scientific understanding.

There are several published, peer reviewed papers where kefir grains have been reproduced, either entirely artificially, or by using somewhat natural methods (such as this, or this, and this). 

These incorrect claims of scientists being unable to make kefir grains are possibly because most kefir sold in supermarkets is not usually made using grains.  Supermarket kefir is usually made by adding a very small number of isolated strains to milk.  This is not because scientists can't make kefir grains.  

Commercially produced kefir not being made with grains has nothing to do with scientists' ability or inability to make the grains, its about keeping everything uniform. 

Instead of making kefir by using traditional grains, commercial kefir is usually made by adding a few isolated strains to milk.  Using a very small number of isolated strains ensures consistency of the final product, and makes it easier to batch test for safety.  Kefir made with grains often has vastly more cultures than store bought kefir, but it is different each batch, it changes from season to season.  Foods need to be tested to ensure safety.  Kefir made with grains is very safe, yet it is difficult to test each and every batch to demonstrate its safety, so it is not usually made this way commercially.  

The grains available to home fermenters were originally family heirlooms, passed down through generations.  While kefir grains you get from one person will be slightly different than grains you get from the person next door to them, they are still kefir grains.  

Even though scientists can make kefir grains, you cannot get kefir grains that descended from the ones that were originally made by scientists.  The heirloom grains passed between home fermenters remain the traditional way of making kefir. 

Kefir electron micrograph - image from https://onlinelibrary.wiley.com/doi/10.1155/2020/8839135
Scanning electron micrograph of natural kefir grain

What We Know (and What We Don't)

What we know

  • Kefir was documented in the North Caucasus region of Russia by the nineteenth century.
  • It spread to wider Russia in the early 1900s.
  • Irina Sakharova played a central role in that story.
  • Kefir grains are living microbial communities.
  • Scientists have successfully created kefir grain-like structures.

What we don't know

  • Exactly when kefir grains first formed.
  • Whether today's grains descend from ancient fermented milk cultures.
  • Whether biblical or religious stories have any historical basis.
Unlike written history, microbial communities don't leave an easily traceable fossil record, so finding the source of the very first kefir grains is extraordinarily difficult.

Kefir Today

By the late twentieth century, kefir had spread well beyond Russia and today is produced around the world.

There are various companies mass producing and selling what they call kefir.  These fermented milk drinks are marketed as kefir, but they are usually produced using a few isolated bacterial cultures rather than traditional kefir grains.  There are also some sachets that are used to make fermented milk, this is meant to taste vaguely similar to kefir.  Commercial kefir generally contain far fewer microbial species than traditional grain-fermented kefir, and is manufactured for consistency rather than wide microbial diversity.

After looking through the myths, archaeology, scientific papers and historical records, one thing becomes clear: the real history of milk kefir is fascinating enough without embellishment.  We still don't know exactly where kefir grains first appeared, but we know considerably more than many websites suggest, and the documented journey from the Caucasus to modern kitchens is remarkable in its own right. 

milk kefir needs some air to perform well
I cover with a strainer, but a cloth also works

Why the origin of kefir grains is such a mystery

Unlike yoghurt cultures, kefir grains are complex self-organising microbial communities.  They don't fossilise easily, they weren't deliberately invented, and before the nineteenth century almost nobody wrote about them. 

That combination makes tracing their true origin extraordinarily difficult. 

Where to get kefir to ferment at home

If you want to try fermenting milk kefir at home, you need to get some kefir grains.  These are not a type of 'grain', it is just their common name.  Much like a sea monkey is not a type of monkey, and a sea horse is not a type of horse, milk kefir grains are not a type of grain.  

Milk kefir grains are complex and ever changing colonies of beneficial bacteria and yeasts growing in a matrix of kefiran.  Kefiran is a microbial exopolysaccharide and is thought to be incredibly beneficial, this is often missing from commercial kefir flavoured drinks.  Milk kefir is super easy to make, while slightly more work than filmjölk, it is about the same effort as kombucha.

If you want to try making milk kefir yourself, For Australian readers, if you want to try this yourself, I sometimes sell traditional milk kefir grains.  My kefir grains are heirlooms, they contain living microbes, and they will live longer than you if they are looked after. 

Disclaimer: This post contains affiliate links.  If you buy through these links, I may earn a small commission at no extra cost to you.

If I don't have any spare kefir grains to sell, for Australian readers, I recommend sourcing Milk kefir starter culture.

For US and international readers you should consider checking Amazon for Milk kefir grains.

Related kefir articles and guides

If you want to go beyond the history and try some kefir for yourself, here are some of my related kefir guides and experiments:


Wednesday, 5 August 2026

Milk Kefir vs Yogurt: What's the Difference and Which Is Easier to Make at Home?

Milk Kefir vs Yogurt: What's the Difference?

If you've been thinking about making your own cultured dairy products, you've probably come across both milk kefir and yogurt.  At first glance they seem very similar.  Both are made by fermenting milk, both contain beneficial bacteria, and both have been enjoyed for centuries.

Although I've made milk kefir for many years, filmjölk for several months, kombucha for years, and regularly make traditional kefir farmer's cheese (tvorog), I've never made true yogurt.  Rather than pretending otherwise, I thought I'd compare them based on my experience with kefir and the characteristics of each fermentation.

For me, milk kefir has to be one of the easiest and most reliable fermented foods to make at home. 

Although this article focuses on milk kefir and yogurt, I'll occasionally mention filmjölk because it's another cultured milk that I've been making regularly.  

In this article

  • What milk kefir and yogurt have in common

  • The main differences between kefir and yogurt 

  • Which is easier for beginners

  • Which one I prefer

Disclosure: This article contains Amazon affiliate links.  If you purchase through these links, I may earn a small commission at no extra cost to you.  I only recommend products I genuinely use or believe would be useful.
Heirloom milk kefir grains
My Milk Kefir Grains 

Equipment I Use

For Australian readers I recommend:

For US and international readers, don't use Amazon Australia as the postage is too high, instead you should consider the same items from International Amazon:

Short on time?  Here's a quick comparison before we look at each cultured milk in more detail.
Feature Milk Kefir Yogurt
Starter Culture Living kefir grains Yogurt starter culture
Fermentation Temperature Room temperature Warm incubation (typically 40–45°C)
Time Usually about 24 hours Usually 4–12 hours
Microorganisms Bacteria and yeasts Mainly beneficial bacteria
Equipment Needed Jar and strainer Often a yogurt maker or other way to keep milk warm
Reusable Culture Yes, grains usually grow and multiply Yes, can often be re-cultured for several batches
Texture Drinkable to thick, depending on fermentation Usually thick and spoonable
Ease of Making at Home Easier for most beginners Straightforward if you have a warm place to culture it

What is Milk Kefir?

Milk kefir is a fermented milk drink made using living kefir grains.  These aren't cereal grains, they are small clusters of bacteria and yeasts living together in a natural symbiotic culture.

The grains are added to fresh milk and left to ferment at room temperature, usually for around 24 hours.  Once the kefir has thickened, the grains are strained out and reused indefinitely.

Read my guide: Making Milk Kefir at Home

If you're new to kefir, you may also find these helpful:

What is Yogurt?

Traditional yogurt is made using specific bacteria, most commonly Lactobacillus bulgaricus and Streptococcus thermophilus.  Unlike milk kefir, yogurt doesn't use reusable grains.

Instead, a small amount of yogurt containing live cultures is mixed into warm milk and held at a fairly constant warm temperature until it thickens.

This means yogurt generally requires more temperature control than milk kefir.  My house gets too cold to make yogurt without an incubator,  the added cost of buying and running an incubator or yogurt maker, as well as the bench space they take, are largely why I don't make yogurt at home.

Milk Kefir vs Yogurt

1. Starter Culture

The biggest difference is the starter culture.

Milk kefir uses living kefir grains that continue growing and multiplying over time.  I've had my kefir grains for years. 

Yogurt uses bacterial starter cultures.  Many people simply reserve a little yogurt from each batch to inoculate the next, although the culture may eventually need refreshing.

Because my kefir grains have been with me for years, I rarely think about buying starter cultures anymore.  

2. Fermentation Temperature

One reason I enjoy making milk kefir and filmjölk is the simplicity.

I simply leave it on the kitchen bench and let it ferment at room temperature.

Yogurt usually needs a consistently warm environment while it cultures.  Many people use a yogurt maker, insulated container or another method of maintaining temperature.

That extra step isn't difficult, but it is another thing to manage.  It also takes more space than a jar of kefir. 

3. The Microorganisms

Milk kefir contains both bacteria and yeasts.  While the exact species vary over time, kefir often has a far greater microbial diversity than yogurt

Yogurt contains a smaller number of species of beneficial bacteria but generally no yeasts.

This gives kefir a more complex fermentation and a slightly tangy flavour that changes as it ferments.

4. Taste

Yogurt is common in supermarkets, most people reading this would know what it tastes like.  Yogurt is generally milder and creamier than milk kefir.  

In my experience, fresh milk kefir has a pleasantly tangy flavour.  If it's left longer, it becomes more acidic and eventually separates into curds and whey. 

I sometimes leave a batch of milk kefir fermenting for a week or so, it gets very sour at times.  I also deliberately over ferment milk kefir and use it to make fresh farmer's cheese.

I've experimented with longer fermentation times in both milk kefir and filmjölk.  For example, I deliberately left one batch of filmjölk fermenting for four weeks just to see what would happen.  The result surprised me.

Read the experiment: What Happens if You Ferment Filmjölk for 4 Weeks?

5. Texture

Fresh milk kefir usually pours easily, although it thickens depending on temperature, milk, and fermentation time.  At certain times of year my kefir is slightly bubbly, this is from yeasts being very active.  

Yogurt generally has a thicker, spoonable consistency.

Filmjölk is a Scandinavian fermented milk that sits somewhere between the two.  Like yogurt, filmjölk is never effervescent. 

Related article: Kefir vs Filmjölk: Which Is Better for Beginners?

6. Looking After the Culture

One thing I enjoy about milk kefir is that the grains contain living organisms.

As long as they're fed regularly with fresh milk, they continue growing.  Over time you'll usually have extra grains to share or use in additional batches.  I've found them surprisingly resilient.

Home made milk kefir
Straining milk kefir grains

Which Is Easier for Beginners?

For most beginners, I think milk kefir is easier to make consistently. 

Once you have healthy kefir grains:

  • no special equipment is needed
  • room temperature usually works well
  • the grains can be reused indefinitely
  • they often multiply over time

Yogurt certainly isn't difficult, but it generally requires maintaining the correct temperature during fermentation.

Equipment I Use

If you'd like to make milk kefir, I sometimes sell kefir grains when I have extra.  If you need kefir starter culture and I don't have any for sale, you can order kefir and other equipment from Amazon along with other items I genuinely find useful.

For Australian readers I recommend:

For US and international readers, you should consider:

I've found that wide-mouth jars are much easier to clean than narrow-neck bottles, particularly if the kefir thickens more than expected.  Thermometer strips are optional, but they are fun and surprisingly accurate, plus once you have them you find a heap of uses for them. 

For Australian readers who decide yogurt suits them better, you will need a good yogurt maker.  This 6 jar yogurt maker is meant to be ideal.

For US and international readers, this 6 jar yogurt maker is the one I would recommend.

Which Do I Prefer?

Although yogurt is extremely popular, I've never felt the need to start making it because milk kefir and filmjölk already suits my family so well.

Milk kefir is easy to make, forgiving if life gets busy, and the grains continue producing batch after batch with very little effort.

It has also become the basis for several other foods I regularly make, including fresh kefir cheese.

If you're deciding between the two, there's no wrong choice.  Both are traditional cultured dairy foods with long histories.  For my kitchen, though, milk kefir has become the clear favourite.

Over fermented milk kefir teady to make tvorog
Milk kefir separating, good for tvorog

Frequently Asked Questions

Is milk kefir healthier than yogurt?

Both are nutritious fermented dairy foods containing beneficial microorganisms, but they use different cultures.  Milk kefir generally contains a wider variety of bacteria and yeasts, while yogurt is usually made using a smaller number of bacterial species.  Rather than asking which is healthier, I think it's more useful to choose the one you'll enjoy making and eating regularly.

Is milk kefir easier to make than yogurt?

In my experience, yes.  Milk kefir ferments happily at room temperature and the grains can be reused indefinitely.  Yogurt usually needs to be kept at a consistently warm temperature while it cultures, which often means using a yogurt maker or another method of incubation.

Can you make milk kefir without kefir grains?

Traditional milk kefir requires living kefir grains.  Powdered starter cultures are available, but they don't usually grow and multiply in the same way as genuine kefir grains.  That's one reason I prefer using live grains.

Does milk kefir taste like yogurt?

They taste similar but not identical.  Fresh milk kefir has a tangier flavour and is often slightly fizzy because it contains both bacteria and yeasts.  Yogurt is usually milder, creamier, and often has a more consistent flavour.

Can I use yogurt instead of milk kefir?

It depends on the recipe.  Both are fermented dairy products, but they behave differently because they contain different cultures and have different textures and flavours.  In recipes specifically developed for milk kefir, I usually recommend using kefir for the best results.

You might also enjoy

Books That Helped Me Learn Fermentation

If you enjoy making kefir, like to learn more about traditional fermentation, these are some of the books I've found useful over the years.  Fermentation is one of those hobbies where a good book is often more useful than buying lots of equipment, because understanding the process lets you improvise.

These are some of the books that can be purchased through Amazon that helped me when I started experimenting with kefir, cultured dairy, and other fermented foods.

Wild Fermentation - this is an excellent starting point for anyone interested in cultured foods, covering a range of traditional ferments including dairy, vegetables, and beverages.

The Art of Fermentation - this is a comprehensive resource for anyone interested in traditional fermented foods, including cultured dairy products such as kefir, yogurt, and other heirloom ferments.

Ferment For Good: Ancient Foods for the Modern Gut: The Slowest Kind of Fast Food - is a practical introduction to traditional fermentation, covering everything from sauerkraut and kefir to kombucha and sourdough, with a focus on improving gut health through homemade fermented foods

Nourishing Traditions - A traditional foods cookbook exploring old-fashioned food preparation methods, including cultured dairy, fermentation, soaking, and preserving techniques.

Saturday, 25 July 2026

Easy 2-Ingredient Buckwheat Sourdough Bread Without a Starter

 

My Simple Experiment Making Buckwheat Sourdough Bread with Two Ingredients and No Starter

You can make a simple buckwheat sourdough bread using only soaked buckwheat groats and home made active kombucha.  I tried it as an experiment and it fermented successfully without a traditional sourdough starter or commercial yeast.

Sometimes the best kitchen experiments start with a simple question.  I already had kombucha continuously brewing, a bag of buckwheat in the pantry, and I knew both kombucha and sourdough rely on live yeasts.  That got me wondering: could I make buckwheat sourdough bread using just those two ingredients?  There was only one way to find out.

In its simplest form, sourdough is a mix of yeasts that have partially digested some flour, and this mixture is baked to make bread.  

I then started thinking about the living cultures I keep that contain yeasts.  I make milk kefir, I have filmjölk, and I brew kombucha, two of which contain (among other things) many species of live yeasts.  While commercial baker's yeast is typically a single species, sourdough cultures often contain a diverse mix of wild yeasts and bacteria. 

At this point in time I am not loving wheat.  While I have had enough of wheat for now, I am particularly fond of buckwheat.  I eat buckwheat for breakfast every day.  I began to think if I have many species of living yeasts, and I have buckwheat, why not try to make sourdough buckwheat bread.

I figured I could get some buckwheat, mix with kombucha, make it into a dough, let it ferment for a while, and bake it into a sourdough bread.  Sounds simple enough, surely nothing much could go wrong.  Worst case scenario it would taste bad, and I would feed it to the chickens.

I gave making buckwheat sourdough bread a try, and it worked well.  I was almost surprised at how simple the process was and how good the bread turned out. 

Two ingredient buckwheat sourdough bread
Buckwheat sourdough bread

I Made Up My Own Recipe

After trying this I looked on the internet for sourdough buckwheat recipes.  In hind sight I should have looked for recipes first just in case this wasn't just common sense.  

It didn't matter too much in this case because it seems I was on the right track, there are a bunch of recipes on the internet that do pretty much what I tried.  

Sourdough certainly has its complexities, but for a simple loaf like this, common sense gets you surprisingly far.

Sourdough buckwheat bread - first attempt

My recipe did not make enough dough.  Given the size of my bread tin, it would have been better using 2 cups of buckwheat and 1 cup kombucha.  I also think had I left it to ferment longer it would have been fluffier.  Other than that, I could not be happier with this attempt.  

My super simple buckwheat sourdough recipe 

(next time I will double the ingredients).

Ingredients:

1 cup raw buckwheat groats 

1/2 cup kombucha liquid

Instructions:

1) Soak 1 cup raw buckwheat groats in water for 6 (or more) hours. 

2) Drain liquid, but do not rinse.

3) Put buckwheat through blender until it becomes liquidy.

4) Add 1/2 cup of kombucha liquid.  Blend until mixed together.

5) Put in something that is not metallic, cover to keep out insects but still lets in air.  Leave overnight to ferment.

6) Line a bread tin with baking paper.  Add the buckwheat / kombucha dough (this could be left to rise for fluffier bread).

7) Bake in oven around 180C for about an hour. 

Buckwheat kombucha slurry from step 5

This post contains affiliate links.  If you buy through these links, I may earn a small commission at no extra cost to you.  I only recommend products that I use myself or would happily use.

If you'd like to try this recipe yourself, you'll need raw buckwheat groats.  I am based in Australia and usually buy raw buckwheat groats because they work well for breakfasts, sprouting, and experiments like this sourdough bread.  
For US and international readers, these are the raw buckwheat groats I would recommend.  

You will also need active kombucha.  I used homemade kombucha from my continuous brew system, but any active, unflavoured kombucha should work.  

If you're interested in brewing your own, I explain the process in my continuous brew kombucha guide.  Making kombucha costs me under 20 cents per liter to make at home, so it is far more cost effective than buying it.

To brew kombucha, you will need active Kombucha SCOBY, I offer them when I have extra, and I can post throughout Australia.  If I don't have any I highly recommend Oliver's Kombucha available through Amazon.  
I also use a large glass beverage dispenser with a tap, which makes continuous brewing simple.  

For US and international readers, I can't post to you so I recommend this kombucha SCOBY on Amazon, opt for the smaller size as they are more cost effective and grow very fast.  For a glass dispenser with tap, I would recommend a dispenser such as this one

Ready for baking - I could have let it rise first

It had some bubbles, but would have been fluffier had I left it longer

The End Result Was Good

The bread looked nice, smelled ok, and tasted good.  

The bread it made was a bit thin as I did not use enough ingredients for the size of the bread pan.  It may have been even nicer if it was fluffier.  

You can see some little holes, these are from the bubbles while it fermented.  Had I left it in the bread tin for a few hours it would ferment more and be more fluffy.

Buckwheat sourdough loaf

It was so thin that it ended up looking more like brownies than bread.  As it was so thin, and looked like a brownie, I sliced it into little pieces instead of traditional bread slices.  This seemed to work well.

I put some butter between each of these little pieces.  The loaf was warm when I added butter, and it melted the butter into the bread.  Most of the butter was soaked into the bread.  I imagine this type of bread would work well with honey comb. 

I put butter between these slices and let it melt in to the bread

I had a little bread left over that I ate the next morning.  It may be my imagination,  but it seemed fluffier.  I liked it more the second day. 

Other than wanting to double the recipe as the loaf produced was too small, the only down side I can see to this recipe is the price.  It's too expensive to make this more than once in a while, especially if I use 2 cups of buckwheat. 


Buckwheat sourdough bread

Related Fermentation Articles

If you enjoy experimenting with fermented foods, you might also find these guides helpful:

Final Thoughts

I thought it was good fun to make buckwheat sourdough bread.  Next time I will use milk kefir instead of kombucha, and see what that is like.  

I plan on making this again.  With a slightly larger batch and a longer second rise, I think it has the potential to become a really enjoyable homemade loaf.  Even if it never replaces everyday bread, it was a fun experiment and another reminder that fermentation often rewards curiosity.


Saturday, 18 July 2026

What Happens if You Ferment Filmjölk for 4 Weeks? (I Tried It)

The Four-Week Culture: What Happens When Filmjölk Lives Too Long?

Fermentation is a dance with living organisms, and usually, we step in right when the rhythm is perfect. With filmjölk, that sweet spot is normally around 24 hours on the counter. But what happens if you just let it keep going?  Driven by pure curiosity, I left a batch of traditional Swedish filmjölk fermenting for an entire month, tasting it and documenting the changes every seven days. 

From subtle changes in texture to a dramatic transformation in flavour and appearance, here is what happens when you push this countertop culture to its absolute limits, week by fascinating week.

Filmjölk still edible after 14 days
Whey separation after two weeks of room-temperature fermentation

Safety First

Wild fermentation is a beautiful process, but safety should always come first. 

This post documents my personal experiment to observe microbial behavior over an extended period.  Standard filmjölk is fermented for 24-48 hours. 

This documents my personal experiment rather than a recommended method of preparing filmjölk.  If mould develops, unusual colours appear, or the culture smells obviously spoiled, discard it immediately.  Never consume dairy that looks or smells unsafe. 

Disclosure: Some links below are Amazon affiliate links.  If you make a purchase through them, I may earn a small commission at no extra cost to you.  I only recommend products that I use myself or would happily use in my own kitchen.

The Baseline: What is Filmjölk Supposed to Be?

Before diving into a month of microbial madness, we need a baseline.  What should filmjölk look, smell, and taste like.

In its standard form, filmjölk is a traditional Swedish fermented milk product.  Unlike regular yoghurt, which requires high temperatures to culture, filmjölk relies on several mesophilic bacteria.  These microbes thrive at room temperatures, allowing the milk to ferment in a jar on my kitchen counter. 

Under normal circumstances, the fermentation process is short and sweet, generally lasting anywhere from 18 to 48 hours.  

I culture mine in simple glass jars.  I strongly prefer wide-mouth fermentation jars because they're easier to fill, clean and scoop from than recycled jars with narrow necks.

For Australian readers I recommend these wide-mouth fermentation jars.

For international readers these are the wide-mouth fermentation jars I recommend.

A standard batch of homemade filmjölk should hit these notes:

Texture: Thick, smooth, and distinctly pourable.  It should comfortably coat the back of a spoon, sitting right in the goldilocks zone between regular milk and thick yoghurt.  I prefer mine thicker, so generally allow it to ferment a little longer. 

Flavour: Mildly tangy and acidic with a unique, subtle buttery undertone.  This buttery aroma comes from diacetyl, a natural byproduct of the mesophilic fermentation process.  My kids say it is like drinkable sour cream. 

Appearance: Uniformly white, glossy, and completely cohesive, with little to no separation of liquid whey.  Photographing filmjölk isn't easy.  A fresh batch looks remarkably similar to ordinary milk in a photograph.

This is the comforting, delicious baseline we are aiming for.  

But what happens when you leave those living bacteria in charge for 600 hours longer than they expect?  Let’s find out.

Summary of filmjölk over-fermentation experiment

Fermentation TimeTextureFlavourMy Verdict
24–48 hoursSmooth, thick and pourableMildly tangy with buttery notesExcellent
7 daysThicker with slight whey separationNoticeably sharper but still pleasantStill Very Good
14 daysFirm curds with lots of wheyQuite acidicEdible, but not my favourite
21 daysOdd textureUnusual aroma and flavourI stopped serving it to my kids
28 daysVery strange appearance and textureUnpleasantI wouldn't eat it again - possibly unsafe


Week 1: The Subtle Shift in Tartness

After seven days the filmjölk was noticeably thicker than normal and had begun to separate slightly, with a small amount of whey collecting around the edges.  The flavour had become noticeably more acidic, but it still retained the buttery notes that make filmjölk distinctive.

At this stage I was still happy to eat it, and my kids tried some as well.  None of us noticed any ill effects, although the stronger flavour was starting to move away from what I normally enjoy.

One unexpected lesson from this experiment had nothing to do with fermentation.  I usually culture filmjölk in wide-mouth jars, but this time I used a recycled narrow-necked jar.  Every time I scooped some out I made a mess, which reminded me why wide-mouth fermentation jars are so much more practical.  

This experiment reminded me why I normally use wide-mouth fermentation jars.  They're much easier to clean and make it far easier to remove thick filmjölk without making a mess.

For Australian readers I recommend these wide-mouth fermentation jars.

For international readers these are the wide-mouth fermentation jars I recommend.

Filmjölk  after 7 days fermentation
Filmjölk getting thicker after 7 day ferment

Week 2: Separation and the Rise of Whey

By the second week the changes became much more obvious.  A significant layer of whey had separated from the thick curds.  I poured off most of the separated whey before tasting the thicker curd beneath.

This separation is fairly normal in cultured dairy.  I also see similar whey separation when making farmer's kefir cheese or tvorog.

The remaining curd had become quite firm.  I could slice pieces away with a spoon and they briefly held their shape before slowly collapsing.  The flavour was still recognisably filmjölk, although much sharper and less pleasant than a normal 24-hour batch.

I still considered it edible at this stage, even if it was no longer as enjoyable.  Visually it started looking a little strange, but there were no obvious signs of spoilage such as mould or discolouration.

Filmjölk 14 day fermentation experiment
Filmjölk after 14 day fermentation is still good

Week 3: Crossing Into Unknown Territory

After three weeks the filmjölk had changed enough that I became cautious.  The texture had become unusual and the aroma was no longer the familiar buttery smell of fresh filmjölk.  It wasn't the smell of spoiled milk, but it also wasn't something I found overly appealing.

I tasted only a small amount.  I didn't become ill afterwards, but this was the first point in the experiment where I even questioned whether continuing to taste it was a sensible idea.  Because of that uncertainty I didn't let my children try any.

Although I can't say exactly what microbial changes were taking place, it seemed likely that the balance of microorganisms had shifted considerably, although I can't say exactly what was happening without laboratory testing. 

Filmjölk after 21 days of fermentation

Week 4: The Ultimate 30-Day Result

After four weeks the filmjölk no longer resembled something I wanted to eat.  The texture had become strange, the smell was unpleasant, and although I tasted a tiny amount out of curiosity, I had no desire to eat any more.

I didn't experience any illness after that small taste, but I certainly wouldn't recommend intentionally fermenting filmjölk for this long.  Even if it happened to be microbiologically safe, the flavour and texture had deteriorated to the point where there was little reason to continue.

One surprise remained.  Before discarding it, curiosity got the better of me.  I used a spoonful of the four-week-old filmjölk as a starter culture for fresh milk.  To my surprise, it fermented into what looked, smelled, and tasted like perfectly normal filmjölk after 24 hours.  I expected the culture to fail completely or need several generations to recover, but that wasn't what happened.  This was the biggest surprise of the entire experiment.

I simply added a spoonful to fresh milk at room temperature and left it to ferment as normal.  I don't usually measure the temperature exactly, but if your house varies a lot, a thermometer strip can be helpful.

For Australian readers, I recommend these thermometer strips.  They are inexpensive, adhesive, simple to use, and surprisingly accurate.

For readers from the US and other countries, these are the thermometer strips I recommend.

Side note after 4 week fermentation 

One unexpected casualty of this experiment was the jar itself.  The narrow neck made cleaning almost impossible after a month of thick fermented milk, so I eventually gave up and recycled it.  It's another reminder of why I almost always use wide-mouth fermentation jars. 

After throwing away this jar, I was reminded why I almost always use wide-mouth jars for fermentation.  They cost a little more than recycled jars, but after years of making kefir, filmjölk and kombucha I think they're well worth it.

For Australian readers I recommend these wide-mouth fermentation jars.

For US and other international readers these are the wide-mouth fermentation jars I recommend.

This Is Why I Typically Use Wide Mouth Jars


The Verdict: Is 4-Week Filmjölk Edible?

If the question is "Can filmjölk ferment for four weeks?", then the answer is clearly yes.

If the question is "Should you eat four-week-old filmjölk?", my answer is no.

I didn't become ill after tasting small amounts throughout the experiment, but by the third week I was no longer confident enough to recommend eating it, and by the fourth week it simply wasn't enjoyable anyway.  

Frequently Asked Questions

Can you ferment filmjölk for a week?

Yes.  Mine became noticeably thicker and more acidic but was still pleasant to eat.

Can filmjölk ferment for two weeks?

It can, although mine separated into curds and whey and the flavour became sharper.

Can filmjölk ferment for a month?

Mine did, but by that stage the texture, smell, and flavour had deteriorated so much that I wouldn't recommend eating it.  I probably could have fermented it longer, but I didn't enjoy eating it after a month and decided that even longer would likely be less pleasant.

Can over-fermented filmjölk still be used as a starter?

Surprisingly, yes.  In my experiment, a four-week-old culture still successfully fermented fresh milk into a normal batch.

Why did my filmjölk separate into curds and whey?

Whey separation is a normal part of extended fermentation.  As the culture becomes more acidic, the milk proteins tighten and release liquid whey.  Small amounts of separation are perfectly normal, although excessive separation usually means the filmjölk has fermented longer than intended.

Does filmjölk keep fermenting in the refrigerator?

Yes, although much more slowly.  Refrigeration greatly slows the bacteria, but it doesn't stop fermentation completely.  Filmjölk often becomes thicker and tangier the longer it is left in the fridge. 

Where to get filmjölk starter

Want to try making your own filmjölk at home?  I occasionally have live filmjölk cultures available, along with kefir grains, and other fermentation starters.  You can check my current availability here.

If you're outside Australia or I don't have cultures available, you can also buy a freeze-dried filmjölk starter online.  For readers in the United States, this is the filmjölk starter I'd choose because it's inexpensive, easy to use, and produces authentic filmjölk.

Unfortunately, Amazon Australia rarely stocks genuine filmjölk starter cultures.  You can sometimes find Nordic style mesophilic starter cultures instead. While they don't produce traditional filmjölk, they can make a similar cultured milk and are a good introduction to room-temperature dairy fermentation.  

Related Fermentation Articles

If you enjoy experimenting with fermented foods, you might also find these guides helpful:

How to Make Filmjölk at Home

Filmjölk vs Kefir

Making Milk Kefir at Home

Farmer's Kefir Cheese Recipe

• Two Ingredient Buckwheat Sourdough with Kefir

• Two Ingredient Buckwheat Sourdough with Kombucha

Final Thoughts: The Resiliency of the Culture

Four weeks, one jar, and a massive spectrum of changes.  

A month of continuous fermentation revealed just how resilient a filmjölk culture can be.  The bacteria continued acidifying the milk long after I would normally stop the process, resulting in dramatic changes in flavour, texture, and appearance.

For me, the sweet spot remains somewhere around 24 to 48 hours.  Beyond that, the extra acidity adds little and eventually produces a product that simply isn't enjoyable.

The biggest surprise came at the end of the experiment.  Even after four weeks, a spoonful of the old culture successfully fermented a fresh batch of milk into perfectly normal filmjölk.  The ageing batch had become unpleasant to eat, but the starter culture itself was still very much alive.

Sometimes experiments don't produce a better recipe, they simply teach us where the limits are.