Kefir is fermented milk and a delicious, tingly, refreshing and probiotic alternative to yogurt or water kefir. It is produced when milk kefir lumps are sealed airtight with milk and fermented for 1-2 days. Here is an overview of the most important facts about kefir and how you can make it yourself!
What is kefir?
When people talk about kefir, they are usually referring to milk kefir. This is a microbial culture that, unlike water kefir, ferments milk (instead of water) into a delicious, tingly and probiotic drink and keeps multiplying.
The word name "kefir" probably comes from Turkish ("kef" = pleasant consistency) and refers to the pleasant aroma and pleasant consistency of kefir in the mouth.
Of course, there are also kefir cultures as powder from conventional trade, with which you can also make a fermented drink. However, in our eyes, this is anything but real, original kefir. Real kefir is also called "Tibetan mushroom", "kefir tuber" or "Caucasian milk kefir".
You can also buy it in the supermarket, but the best kefir of all is not available in any supermarket - you can easily make it yourself at home!
According to old traditions, milk kefir originated in the Caucasus and Tibet. Even back then, people knew how to appreciate the drink and how to care for the living microorganisms it harbours and pass it on from generation to generation.
What does kefir taste like and what consistency does it have?
Milk kefir, when strained, looks similar to cauliflower and has the appearance of a tuber. The longer it ferments, the more milk sugar is broken down and the creamier the consistency becomes. If milk kefir ferments for a very long time, it can taste quite sour, which some people still like. If it ferments for a normal length of time, it tastes sweet and sour, tingly and slightly astringent - an aromatic combination!
It is not bad then: due to the acidic milieu, in which carbonic acid is also formed, milk kefir protects itself with other natural substances from foreign contamination by pathogenic germs, which would also be harmful to us.
The yeast contained in kefir also forms carbonic acid when it breaks down sugar. You will feel this when you taste your kefir. It gives it a pleasant tingling sensation on the tongue. Depending on how you make the milk kefir (for example, through a secondary fermentation), you can also create more carbonic acid in the kefir. We also call kefir that we make this way "kefir champagne". The carbonic acid simply feels nicer than carbonic acid added by industrial processes. You can read more about secondary fermentation in a separate article.
If you are already familiar with fermentation and particularly like carbonic acid, we can also recommend our water kefir set, kombucha set and our honey kombucha, JUN. These are just as unique and full-bodied.
- The fermentation of milk into kefir is quite quick and takes on average about 20-48 hours, depending on the quantity, temperature and other environmental influences on the culture. During this process, yeasts and bacteria work in symbiosis.
- For fermentation, milk (fat content 1.5% or 3.5%) is put into a clean fermentation vessel with the milk kefir nodules (30g per litre of milk), sealed airtight and left to stand for 20-48 hours in a place protected from light and temperature at room temperature.
- A jar with a volume of 1-2 litres, with a rubber stopper and an opening that is not too small, is suitable as a fermentation vessel.
- After fermentation, strain the kefir with a plastic sieve (important, no metal sieve!) and fill the finished kefir into a clean glass bottle, which you store in the fridge.
- You can then start a new fermentation with the milk kefir lumps that remain in the sieve.
During fermentation, many interesting metabolic products are produced, such as vitamin B, vitamin C, lactic acid, ketone bodies and much more. We advise you to try our milk kefir and see how well you and your digestion feel afterwards.
What happens to superfluous milk kefir nodules?
In addition to various bacteria and yeasts, the milk kefir tuber also contains a large amount of dietary fibre and can be eaten/drunk without any problems. You can do this if the nodules multiply more and more - before you throw away excess milk kefir nodules, try eating them or pureeing them in a smoothie and drinking them.
Kefir for lactose intolerance
Nowadays, many people suffer from lactose intolerance. In real - homemade - milk kefir, lactose is almost completely broken down and metabolised as food for the microorganisms. The finished drink therefore only contains minimal traces of lactose, making kefir a suitable drink for those affected by lactose intolerance.
Things to know about milk kefir
- At first glance, kefir tubers may look like cauliflower. In contrast, however, they tend to ensure that milk doesn't give you flatulence 😉 .
- Lactic acid bacteria are our old friends who are older than us and with whom we have always lived in symbiosis as living beings. They are located in our intestines and have many important tasks. They are also active in the production of wild ferments/wild fermented vegetables. We have exciting recipes for fermented vegetables on our blog, e.g. for fermented radishes or making sauerkraut yourself.
- While cheese, yogurt, quark and other dairy products are formed by bacteria fermenting milk, yeasts are also involved in the fermentation of kefir.
- If you take good care of your milk kefir, it can last a lifetime. If you don't feel like having milk kefir, you can store it in the fridge for several weeks. After that, it may need 1-2 brewing cycles to regain its old vitality, but that's what you need when you wake up from hibernation, isn't it 😉 The older the kefir, the better.
- The older a kefir tuber is, the thicker and more voluminous it is. Theoretically, it can grow indefinitely. There are even photos of fist-sized tubers floating around on the internet! This is all very interesting and certainly some people can compensate for things that would otherwise be too small, but size is not really the decisive factor here:
- Smaller tubers are actually more efficient because they have a larger surface area in relation to their diameter compared to large tubers. You can also simply break large tubers into smaller ones, giving "old, hidden" bacteria access to fresh nutrients again.
- Even though kefir is white, it is not necessarily the fast rabbit among ferments. Milk kefir multiplies very slowly. You can only expect it to double in quantity after about a month. We call milk kefir "white gold" not only because of this, but also because of its great properties, and we treat it with the utmost care and love. By the way, it also senses this and sometimes forms an extra tuber out of gratitude.
Kefir - Easier to maintain than a tamagotchi
In our opinion, no ferment is as easy to make as milk kefir. No boiling, no stirring, no long list of ingredients:
Milk kefir tubers off into the jar, milk in (goat's, sheep's and cow's milk are all suitable here) and leave to stand for about 24 hours in a place protected from light and temperature. You can find out how to make your own milk kefir in our very simple instructions!
You will eventually see the whey (the transparent, slightly cloudy liquid) settle at the bottom. This contains many amino acids. You can bring it to the gym with your fitness freak buddy. It will be better for him than taking protein powder 😉 .
Above, on the other hand, the milk kefir tubers have settled in seventh heaven in a white cloud of an, aromatic, delicious, creamy home.
There are no limits to your experimentation!
In my kitchen, I love to experiment around with all sorts of fruits, herbs, spices and sweeteners. It's a really meditative, relaxing activity for me. My girlfriend even threatened me once, like a junkie, that if this continued I would have to choose between her and this white stuff.
The slight tartness of milk kefir in combination with something sweet or tart is just dreamy. I even think that things that I normally don't tolerate so well because I've neglected my body a bit, I tolerate better in combination with milk kefir. For example, when I eat something very spicy, cereals (muesli/bread) or unfermented dairy products. Then I drink a glass of kefir afterwards and my digestion gets going much better!
The right milk for kefir
Milk kefir is also fantastic as a dip and part of smoothies. Many vitamins are fat-soluble. How fitting that there are also small amounts of fat in the finished kefir!
But not all fat is the same. Many vitamins are fat-soluble, but so are some toxins. Therefore:
If you use good milk, which in the best case comes from animals kept in a species-appropriate manner (pasture-raised, hay-milk, Demeter) and the animals have also been exposed to daylight, then this milk is something completely different than the cheap milk from the discounter.
In addition, you torture fewer animals and do something good for regional farmers, the environment and yourself. I also prefer to use full-fat milk with 3.5% fat. By the way, we don't make any compromises when it comes to production - organic and products from species-appropriate and fair production are obligatory for us!
Kefir ingredients and microorganisms
What microorganisms, ingredients and nutritional values are contained in kefir? You will find a detailed overview below:
After a standard fermentation process lasting 24-36 hours, the following ingredients can be found in the finished and strained kefir drink:
- 90% water
- Fat, depending on the milk used
- 3 % protein (mainly hydrolysed)
- 6% sugar and sugar breakdown substances
- 0.7% minerals
- 0.5-1% alcohol
- 1% lactic acid
- 0.3 % acetic acid
- 0.2% CO2
The exact composition of microorganisms in milk kefir differs depending on the origin and fermentation conditions. Usually, the following microorganisms are found in kefir, which are later also found in the finished drink and have a probiotic effect:
Kefir nodules under the microscope (from de Oliveira Leite, 2013): Clearly visible is the fibre matrix (filaments), the bacteria (small microorganisms) and yeasts (large nodules) living together in a symbiosis.
- Lactobacillus kefir, Lactobacillus acidophilus, Lb. casei. Lb. helveticus, Lb. bulgaricus, Lb. parakefir, Lb. plantarum, Lb. delbrueckii subsp. delbrueckii, Lb. rhamnosus, Lb. fructivorans, Lb. paracasei, Lb. fermentum, Lb. reuteri, Lb. brevis, Bifidobacterium bifidum, Lactocossus lactis, Streptococcus thermophilus, Enterococcus durans, Pediococcus acidilactici, Acetobacter aceti.
- Zygosaccharomyces sp., Candida lipolytics, Candida holmii, Candida maris, Candida kefyr, C. lambica, Kluyveromyces marxianus, Kluyveromyces lactis, Saccharomyces cerevisiae, Saccharomyces fragilis, Saccharomyces lactis, Zygosaccharomyces rouxii, Torulaspora delbrus, Torulaspora delbrueckii, Kazachstania aerobia, Geotrichum candidum.
Minerals and vitamins:
The kefir drink and especially the kefir nodules are a rich source of the following minerals and vitamins - there is still disagreement about the exact amounts, but all of the following nutrients are present in amounts that are high for a fermented product and relevant for our bodies:
- B vitamins
- Vitamin C
Make your own milk kefir
You could make your own yogurt by heating yogurt from the supermarket with milk and leaving it under the heating overnight. Unfortunately, this won't work with kefir from the supermarket - you need a starter culture that you buy once and which then works for you for the rest of your life.
In this respect, the one-time investment in a starter culture or starter pack pays off very quickly and you will notice that homemade kefir is not only healthier and tastier, but also cheaper than the one from the supermarket - an all-round worthwhile investment!
Did we mention that kefir fermentation is very easy, very quick and really fun?
We have worked for a very long time to be able to offer a starter set for kefir and are proud to present it to you in our shop. We designed the production of the starter culture together with microbiologists and food technologists, it is built according to the highest quality standards - and the fermentation (exact instructions enclosed in the starter set) is described in a simple and understandable way.
Conclusion Milk kefir
Milk kefir is a refreshing, delicious, digestible and probiotic drink that anyone can make very easily at home.
Milk kefir (or simply kefir) is made when milk (preferably organic milk) is fermented with milk kefir nodules for 20-48 hours at room temperature and sealed airtight. Lactose and milk proteins are broken down and metabolised into many good nutrients. This makes milk kefir a refreshing drink rich in vitamins and nutrients, as carbonic acid is also formed.
Due to the numerous microorganisms, milk kefir is probiotic and very beneficial for healthy intestinal function.
The fermentation of milk kefir can be done by anyone at home with very little effort and equipment. Of all the ferments we have tried so far, kefir is definitely the easiest, goes the fastest, and has a phenomenally delicious result to offer!
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