Kefir vs Filmjölk: Which Cultured Milk Is Easier and Better for Beginners?

Kefir vs Filmjölk: Which Cultured Milk Is Better?

If you're trying to decide between kefir and filmjölk, both are excellent cultured milk products.  After making kefir for several years and filmjölk for several months, I think filmjölk is easier for complete beginners, while kefir offers a little more flexibility once you're comfortable maintaining the grains.

When people first discover fermented milk, they usually hear about kefir.  It's one of the best known cultured dairy products and has a reputation for being incredibly healthy.  Kefir is surprisingly easy to make.

Filmjölk is much less well known outside Scandinavia, despite being one of the easiest cultured dairy products to make at home.  If you can believe this, its even easier to make than milk kefir.  If you haven't tried filmjölk before, I wrote a separate guide showing how I make it at home: How to Make Filmjölk at Home (And Why My Kids Prefer It to Kefir) .

After making milk kefir for several years and filmjölk for several months, I've found they each have strengths.  I still keep both cultures alive because I use them for different purposes.

If you're trying to decide whether to start with kefir or filmjölk, here's what I've learned.

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My home made filmjölk and milk kefir 

What Is The Difference Between Kefir And Filmjölk?

Although both are fermented milk products, they are made quite differently.

Milk kefir is produced using living kefir 'grains'.  These aren't true grains, and pose no danger to anyone with grain allergies.  These grains contain a mixture of bacteria and yeasts that work together to ferment milk.  While there are many fanciful stories told online about the history of milk kefir, the actual history of milk kefir is utterly fascinating.

Filmjölk does not use grains.  Instead, you save a small amount of finished filmjölk and use it to start the next batch.

If you’re deciding which one to start with, the biggest factor is whether you want to maintain kefir grains or prefer a simpler starter-based culture.  From a practical point of view, filmjölk is probably the simpler of the two.

My milk kefir grains 

Quick Comparison: Kefir vs Filmjölk

Feature	Milk Kefir	Filmjölk
Culture type	Kefir grains	Starter culture
Flavour	Tangy, slightly yeasty	Mild and buttery
Texture	Drinkable	Thick and spoonable
Maintenance	Needs grains separated after each batch	Save some finished culture for the next batch
Difficulty	Very easy	Very easy

Filmjölk is thick and spoonable 

Taste: Kefir vs Filmjölk

This is probably the biggest difference between milk kefir vs filmjölk.

Milk kefir has a distinctive tangy flavour that some people love immediately, while others take a little time to appreciate.  Depending on time of year, it can also develop a slight yeasty flavour and sometimes a little natural carbonation.

Filmjölk is much milder.

It has a buttery flavour with gentle acidity that reminds many people of yoghurt, although the texture is smoother and I find it less sour than Greek yogurt.

When I first made filmjölk, I was surprised how easy it was to enjoy straight away.

Which One Do My Kids Prefer?

This surprised me.

I expected everyone to prefer kefir because my kids have grown up drinking it and have always enjoyed it.  

Instead, my children immediately preferred filmjölk.

The milder flavour makes it much easier for people who aren't used to fermented foods, and apparently it's also nicer for kids who grew up drinking kefir.

That doesn't mean kefir is worse.  My kids still like it and drink it most days, they just prefer filmjölk.  Milk kefir just has a stronger flavour.

Making Filmjölk at home - saving some starter for the next batch 

Which One Is Easier To Make?

Both are easy.

Kefir requires one extra step.

After each batch you need to strain out the kefir grains before starting another batch.  I use a plastic mesh strainer because it makes separating the grains quick and simple.

Filmjölk skips this step completely.

To make more filmjölk you simply keep a little from the previous batch and add fresh milk.

If someone told me they had never fermented anything before, I would probably suggest starting with filmjölk because there is less to think about.

Straining my milk kefir grains 

Equipment I Use

I often make both cultures in recycled jars, but they are such a pain to clean.  It's far better to use ordinary glass preserving jars.  They are inexpensive, easy to clean, and the wide opening makes stirring and cleaning easier.

I also keep thermometer strips nearby, especially during winter when my house is cooler and fermentation slows down.  It's interesting how useful these things are. 

Once fermented, I store the finished milk in glass storage jars in the refrigerator.  I keep a lid on while in the fridge, otherwise there is a risk that they will absorb odours and off tastes from the fridge.

I don't use yogurt makers, or incubators, or heating mats to make kefir or filmjölk.  They aren't needed.  My house gets cold over winter, and my ferments always do just fine (althoughsometimestheymight need an extra day before they are ready).

Which One Is Healthier?

This is a common question.

Both contain live cultures, but they are not the same cultures.

Kefir is reported to contain a wider variety of beneficial bacteria and beneficial yeasts than filmjölk, although the exact number depends on the individual culture. 

Filmjölk contains its own traditional cultures and is also a live fermented food.

Rather than saying one is better, I think they are simply different.

I happily consume both.  I personally think of kefir as food and as home remedy medicine, while I only tend to think of filmjölk as food.  

Should You Choose Kefir or Filmjölk?

If you're still undecided, here's a quick summary based on my own experience making both at home.

If you want...	My recommendation
A mild flavour that's easy to enjoy	Filmjölk
A stronger, tangier cultured milk	Kefir
The easiest culture for complete beginners	Filmjölk
A culture with beneficial bacteria and yeasts	Kefir
A thick, spoonable breakfast	Filmjölk
A drinkable fermented milk	Kefir and Filmjölk
The least day-to-day maintenance	Filmjölk
A culture to share and multiply over the years	Both

Which One Would I Recommend?

If you enjoy experimenting and don't mind separating kefir grains, milk kefir is a rewarding culture to keep.  I have kept milk kefir going for years, and I would be really upset if I ever lost it.  I drink milk kefir, I use it on my breakfast in the morning, and use it to make tvorog.

If you want something mild, simple, and easy to maintain, filmjölk is hard to beat.  Given its simplicity, and its mild flavour,  I'm surprised this isn't more commonly made by people at home.

Personally, I don't think it is an either/or decision.

I make both regularly because I like them both and they suit different situations.

I ferment filmjölk with the lid on

Making Kefir and Filmjölk in the Same Kitchen

One question I often get is whether it is possible to make both milk kefir and filmjölk in the same kitchen.

For me, the answer is yes.  I have kept several cultures including milk kefir, kombucha, and filmjölk all going at the same time for years, but I do treat them as separate cultures and take care not to mix them.

I don't share utensils between my kefir and filmjölk.  Each culture has its own jar, spoon, and strainer, which helps reduce the chance of accidentally transferring one culture into the other.

I also handle them slightly differently.  My milk kefir is usually left uncovered while it ferments, which is how I have always made it.  I have always been told that milk kefir is an aggressive culture, and can contaminate other nearby cultures.  My filmjölk is kept covered with a lid while it ferments.

Keeping the filmjölk covered gives me peace of mind that it is less likely to pick up anything from the surrounding environment, especially since I have other active fermented cultures sitting nearby.  

The two cultures are quite different.  Milk kefir grains contain a complex community of bacteria and yeasts, while filmjölk relies on specific lactic acid bacteria.  I like how each tastes, and I like how each has different uses.  I prefer to keep those communities separate rather than risk one gradually changing the other.

My kitchen is not a laboratory, and fermented foods have been made in ordinary kitchens for generations.  However, treating each culture with care makes it easier to keep them healthy and consistent over time.

Where Can You Buy Kefir Or Filmjölk Cultures?

If you want to try making either one, you will need a starter culture.

For kefir, you can start with live milk kefir starter.

For filmjölk, you can use a filmjölk starter culture if you don't have someone nearby who can share some fresh starter.

Both cultures can continue producing batch after batch when cared for properly and can be kept going indefinitely.

I ferment kefir with the lid off

My Recommendation For Beginners

If you have never fermented milk before, start with whichever culture is easiest for you to obtain.

Both are inexpensive to make, forgiving, and require very little equipment.  Both taste great, both have purported health benefits, and both taste remarkably different to one another.

Once you have mastered one, trying the other is very straightforward.

Fermentation Books I Recommend

If you are interested in making kefir, filmjölk, or other fermented foods at home, these are some books I have found useful.

The Art of Fermentation by Sandor Ellix Katz

This is one of the best-known fermentation books and covers a huge range of traditional fermented foods.  It goes well beyond milk fermentation into vegetables, drinks, and other cultures.
Check the current price on Amazon

Wild Fermentation by Sandor Ellix Katz

This is a more approachable introduction to fermentation.  I like it because it focuses on the idea that fermentation has been part of everyday kitchens for thousands of years.
Check the current price on Amazon

Super Gut by William Davis

This book focuses more on gut health and fermented foods.  Some of the health claims are debated, but it contains interesting information about fermented foods and probiotic cultures.
Check the current price on Amazon

Continue Your Fermentation Journey

• Beginner Guide to Making Milk Kefir at Home
• Beginner Guide to Growing Milk Kefir Grains at Home
• How To Make Farmer's Kefir Cheese (Tvorog)
• My Filmjölk Guide

Final Thoughts

After making both milk kefir and filmjölk in my own kitchen, I don't think one is universally better than the other.  They simply suit different people and different situations.

If you enjoy a stronger flavour, want the resilience of kefir grains, or like experimenting with fermented foods, milk kefir is an excellent choice.  If you're looking for something incredibly simple with a mild flavour that the whole family is more likely to enjoy, filmjölk is hard to beat.

In our house, I now keep both cultures going.  Kefir remains my favourite (largely for sentimental reasons), while filmjölk has become the cultured milk my children ask for most often.  Fortunately, they're both easy to maintain, so there's no reason I can't make both.

How to Make Filmjölk at Home (And Why My Kids Prefer It to Kefir)

Filmjölk (also called Tykmælk in some countries) is a traditional mesophilic fermented milk that I started making in early 2026. If you've never tried it before, imagine something somewhere between drinking yogurt, sour cream, and milk kefir. My kids describe it as "drinkable sour cream".

Unlike ordinary yogurt, Filmjölk does not need to be kept warm while it ferments. It is a mesophilic culture, which means it can ferment at ordinary room temperature, making it remarkably simple to make at home.

The main thing you need is a live Filmjölk starter culture. Once you have an established culture, you can keep using a little from each batch to start the next one.

Filmjölk tastes surprisingly different from milk kefir, even though both are fermented from milk in a jar on my kitchen bench. I enjoy making both, but Filmjölk has become a favourite in our household because it is mild, smooth, and easy to make.

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Filmjölk is like drinkable sour cream

What is Filmjölk?

Filmjölk is a traditional Nordic fermented milk made using mesophilic lactic acid bacteria. Unlike regular yogurt, it does not need to be heated and incubated at a high temperature. It can simply ferment at room temperature.

I have never tried making regular yogurt or Greek yogurt. The idea of needing to heat the milk and then maintain a particular temperature has never appealed to me when there are simpler ways of fermenting milk at home.

Filmjölk is much more convenient. Add some live culture to milk, leave it in a jar on the bench, and wait for it to thicken.

It is also an heirloom culture. Once you have a healthy culture established, you can reserve some finished filmjölk and use it to inoculate the next batch rather than buying new starter every time.

What does Filmjölk taste like?

Filmjölk has a smooth, velvety texture and a mild but quite pleasant flavour. I find it noticeably more buttery and less sharp than milk kefir.

My kids describe it as "drinkable sour cream".  They love sour cream, and happily eat it by the spoonful, so their description shows how much they enjoy filmjölk.

Filmjölk can be reasonably thin and pourable, or it can become much thicker depending on how long it ferments. If I leave it fermenting for longer, I get something closer to Filbunke.

Some Filmjölk/Filbunke/Tykmælk I made at home

Filmjölk vs Milk Kefir

Filmjölk and milk kefir are both traditional fermented milk cultures. They are both made in a jar of milk sitting on my kitchen bench, but they produce quite different results.

Filmjölk is milder, smoother, and more custard like, while milk kefir is generally more tangy, acidic, and variable, and may develop a little carbonation depending on the season. Filmjölk is fermented with bacteria, while kefir grains contain a more complex community of bacteria and yeasts.

I enjoy both, but they have different uses in my kitchen. If you are interested, I wrote a blog post about the differences between them.

What is Filbunke?

Filbunke is closely related to Filmjölk, and when making it at home the distinction seems a little blurry. The same culture can produce something fairly pourable or something much thicker and spoonable depending on fermentation time and conditions.

For me, making Filbunke generally means leaving the Filmjölk to ferment for longer. The result is much thicker and closer to a custard or very thick yogurt than ordinary Filmjölk.

I am not particularly concerned about whether what I make would technically be classified as Filmjölk, Filbunke, or somewhere in between. For home fermentation, the important difference is mostly the final consistency.

Filbunke is thicker than Filmjölk

What you need to make Filmjölk

• Live Filmjölk starter culture
• Milk
• A clean glass jar
• Optional thermometer strip

You don't need a yogurt maker, incubator, expensive fermentation machine, or any special equipment.

I often use recycled jars because they're free, but a wide-mouth glass jar is much easier to clean and much more convenient if you're making Filmjölk regularly.

Where I got my Filmjölk starter culture

I started with a live heirloom Filmjölk culture rather than a freeze-dried packet. In my experience, the live culture established easily and has been simple to maintain. Once it was established, I could keep propagating it by saving some finished Filmjölk from each batch.

Live cultures can be difficult to post, however, so dried starter cultures are often easier to find. If you don't know anyone maintaining a live culture, a dedicated Filmjölk starter is probably the easiest way to begin.

I would recommend this starter from Bacillus Bulgaricus for someone trying Filmjölk for the first time.

How to Make Filmjölk at Home

Compared with milk kefir and yogurt, there is surprisingly little information available about making traditional Filmjölk at home. I don't know if I am doing it "right" according to every traditional method, but I can tell you what I do and how it has worked for me.

I add some established Filmjölk starter to milk in a clean glass jar and leave it at room temperature until it thickens.

I usually use a simple screw-top lid. I prefer fermenting Filmjölk with the lid on because I have several other ferments in my kitchen and would rather minimise the chance of something else getting into the jar.

I normally leave it for around 24-48 hours, depending on the temperature and how active the culture is. If I want a thicker result, I leave it longer. Like many other traditional ferments, it doesn't need to be overly precise.

A simple thermometer strip can be useful if your kitchen temperature changes significantly through the year. You don't need one to make Filmjölk, but it can help explain why a batch takes longer in winter than it does in summer.

Once the Filmjölk has thickened, I put it in the refrigerator. I always save a little to start the next batch before I start to eat any.

Saving a little filmjölk starter for a new batch

How much starter should I use?

There are different recommendations for how much starter to use. When I first received my culture, I used a relatively large amount because I wanted to make sure the milk was well inoculated.

My first batch was roughly one quarter starter to three quarters milk. That was considerably more starter than many recipes recommend, I was deliberately being cautious with my first batch because I didn't yet know how active the culture was. It set quickly and developed the smooth, custard like texture I was hoping for.

Once a culture is established and working reliably, I don't think there is much need to obsess over exact measurements. The important thing is to use enough healthy starter to get the new batch fermenting reliably. 

Keeping the Filmjölk culture going

One of the things I like most about Filmjölk is that there are no grains to strain and maintain.

Each time I make a batch, I simply save a small amount of finished Filmjölk before eating or flavouring the rest. That saved portion becomes the starter for the next batch. I save a small amount from the finished batch before eating any.

The culture is kept in the refrigerator when I'm not actively making a batch. It continues to change slowly in the fridge, but fermentation is slowed compared with leaving it at room temperature.

Mine changes with the seasons, and with the temperature. That is normal for a living culture.

My experience making Filmjölk

I first obtained my Filmjölk starter as a liquid culture early in 2026 and wasn't entirely sure what to expect. There was much less information available than I was used to finding for kefir or yogurt.

When it arrived, it smelled a little like butter and a little like sour milk or kefir. It did not smell like rancid milk.

I was surprised by how quickly it established. After that first batch, I simply kept some aside each time and continued the cycle.

My kids like the taste because it is buttery and much more tame than kefir. With kefir they often add honey or other toppings, but they are happy to drink filmjölk without adding anything.

For me, filmjölk has also behaved more predictably than milk kefir. My kefir can vary noticeably from one batch to another, whereas my filmjölk batches tend to be quite similar.

Fermenting filmjölk turned out to be simpler than I expected. Sloshing a little live starter into milk every now and again is not particularly difficult, and the finished culture stores well in the refrigerator.

Filmjölk is not the same as kefir

What happens if you ferment Filmjölk for too long?

Once I had been making filmjölk for a while, I became curious about what would happen if I simply left a batch fermenting for much longer than normal.

My normal sweet spot is around 24 hours, but curiosity got the better of me and I once left one batch going for four weeks and documented what happened. 

Common mistakes when making Filmjölk

• Using too little healthy starter
• Fermenting somewhere that is unusually cold or hot
• Forgetting to save some finished filmjölk before eating the batch
• Mixing flavourings or fruit into the entire batch before reserving starter
• Expecting filmjölk to taste like yogurt
• Expecting every batch to set at exactly the same speed
• Confusing normal fermentation smells with spoiled milk

Filmjölk should develop a pleasantly acidic, cultured smell. If it develops mould, unusual colours, or an obviously rotten or spoiled smell, discard it rather than trying to rescue the culture.

Frequently Asked Questions

Where can I buy Filmjölk starter culture in Australia?

Filmjölk starter culture can be difficult to find in Australia. If you don't know someone maintaining a live culture, you can order starter cultures from Bacillus Bulgaricus here. They post starter to many countries.

What milk works best for Filmjölk?

I use A2 milk as that's what we use in our house. Full cream milk produces a richer result, while lower-fat milk produces a lighter texture. The culture can adapt to the milk you regularly use.

I would not use plant-based milk as a long-term substitute. Filmjölk is a dairy culture and is intended to ferment milk.

How long does Filmjölk take to ferment?

Mine generally takes around 24 hours to thicken, although temperature and culture strength, and room temperature make a difference. I often allow it longer when I want a thicker result.

Can I reuse Filmjölk to make more batches?

Yes. This is one of the main advantages of an established heirloom culture. Save a small amount of finished Filmjölk and use it to inoculate the next batch. 

Does Filmjölk keep fermenting in the refrigerator?

Yes, although much more slowly. I find that Filmjölk can continue to become thicker and more acidic while refrigerated, especially if it is kept for a long time.

Can Filmjölk become too sour?

Yes. The longer it ferments, the more acidic it becomes. I prefer mine relatively young, when it is smooth, mild, and buttery.

Can I make Filbunke from Filmjölk?

Yes. For me, the simplest way to make a thicker Filbunke style ferment is simply to leave the Filmjölk fermenting for longer until it reaches the consistency I want. 

Where to get Filmjölk starter culture in Australia

Filmjölk has quickly become one of my favourite fermented dairy cultures. It is simple to make, requires very little equipment, and produces a smooth, mild cultured milk that my family enjoys.

While I still make milk kefir regularly, Filmjölk has earned a permanent place in my kitchen and is one of the easiest heirloom cultures I have worked with.

Filmjölk is still relatively uncommon in Australia, and obtaining a live starter culture can be more difficult than finding kefir grains. If you want to start making it yourself, this is the starter culture I would recommend for first-time Filmjölk makers.

Once you have an established culture, however, you don't need to keep buying it. I simply save a little from each batch and use it to start the next one.

I mostly make Filmjölk for my family, but occasionally I have more starter culture than I need. When I have healthy cultures available to share, I may list them on my For Sale page, along with other things I have grown, propagated, or cultured.