Kefir and Fruit Bowl

Kefir was the second living food I attempted to make in my kitchen-lab, and it was my first failure. My biggest mistake with this one was my decision to order my kefir grains (the term used to describe the culture that initiates the fermentation process) online in the heat of the summer without using expedited shipping. I had ordered milk kefir grains and water kefir grains separately from two different online sources. The milk kefir grains survived the hot weeklong journey, but the water kefir grains did not fare so well. As it turned out they were DOA, although I did not realize that until my 5th or 6th unsuccessful attempt to brew a batch of "kefir soda" which is basically fermented sugar water. It's actually a lot healthier than it sounds, but in the end I decided water kefir was something I could do without, so my focus here will be on milk kefir.


Milk kefir is a cultured dairy food, that is high in nutrients, full of healthy probiotics and great for digestion and gut health. In its simplest form, it tastes a lot like yogurt with a slightly thinner consistency although it can easily be strained to yield a thicker greek yogurt consistency. By simply tweaking the fermentation and straining schedule, I've found that I can match the flavor and consistency of other dairy products; In our home, kefir has become a delicious alternative for sour cream, cream cheese and goat cheese. The super simple process to make kefir at home begins with whole milk and a few kefir "grains" (which are actually not grains at all but a yeast/bacteria fermentation starter).

Water kefir is very similar, in terms of the health benefits and process, except water kefir grains feed on regular cane sugar (sucrose) dissolved in water or another non-dairy beverage (like coconut water). It produces a sweeter, carbonated beverage that many drink as a healthier alternative to regular pop or soda.



  • Nutrient-dense food, with calcium, potassium and protein.
  • Contains a wide array of digestion-boosting, gut healthy bacteria (i.e. probiotics)
  • The process is extremely easy and involves 1 ingredient, whole milk (other than the kefir grain which can be used indefinitely).
  • Your kefir grains are alive, and if cared for properly will continue to live and multiply indefinitely
  • Most of the milk's lactose is consumed during the fermenting process, so kefir is easily digestible and a great alternative to regular milk products for anyone who is lactose-intolerant.
  • There are studies showing the health benefits of kefir can be significant! If you enjoy getting into the gritty details, here's a clinical study from the NIH, US National Library of Medicine that proves milk kefir to be a useful therapy in the treatment of diabetes.


  • Your kefir grains are alive and must be fed fresh milk every 24 to 48 hours, so you need to have a continuous supply of fresh milk (and possibly a kefir-babysitter if you plan to go away for more than a few days).
  • If you decide to take a break from kefir-brewing, you can try to freeze your grains and reactivate them at a later date but that takes time and patience and not 100% guaranteed.
  • UPDATE: I am so happy to report that I have found the information I crossed out above to be incorrect. I have come up with a simple method to make my kefir in large batches (~1 gallon at a time) which means, with only two of us eating it,  I only need to make it once a week. I store my kefir grains in the refrigerator in between batches and have left them (without a continuous supply of fresh milk) for up to 3 weeks and they are still very happy and healthy. For more on that, be sure to check out my Big Batch Kefir page here.

A typical batch can be anything from 2 cups to 4 cups, and the most convenient cycle is either a 24 or 48 hour cycle. This way, you can get on a regular schedule and start each new batch at the same time every day. There are methods to control the batch size and timing a bit, but before getting into that, read on to learn how simple the process can be.


For information on where you can purchase your kefir culture as well as a complete list of tools, check out my Kefir-Making Tools page here.


In this culturing process, the kefir grains convert the sugars in milk (lactose) into lactic acid;  the result is a creamy, slightly tangy food full of healthy probiotics.

Milk for Kefir

1. Fill a glass mason jar to the 2-1/2 cup mark with fresh whole milk (preferably organic, preferably not ultra pasteurized if you can find it).  Note: I used to warm the milk just to room temperature by placing the jar in a larger container filled with warm water, but I no longer do this unnecessary step. Now I just use milk straight from the refrigerator and it works great!

Kefir in the pantry

2. Drop 1/4 cup of kefir grains into your milk, cover the jar with a coffee filter and rubber band, and place it in a dark place to culture. I keep mine in my pantry. Once your milk is the consistency of heavy cream or liquid yogurt, it's done. This usually takes 24 hours, but you can allow it to culture it for up to 48 hours (depending on how smooth or sour you like it).

3. That's basically it! When your kefir is done to your liking, repeat step 1 to prepare a new batch of fresh milk, and for step 2 you'll be transferring your grains from your cultured batch to your new batch with a plastic slotted spoon or you can pour it through a strainer. You can eat your kefir right away or, if you prefer to eat it cold, cover your cultured kefir with an air tight lid and store it in the refrigerator until you are ready to eat it.



If your grains begin to culture too quickly (i.e. if it get's too sour or fizzy for your tastes) you can adjust your process in any of the following ways:

  • increase the volume of milk (which will increase your daily kefir production)
  • shorten the culturing time (which, again, will increase your daily kefir production)
  • reduce the amount of grains in your batch
  • culture your kefir in a cooler spot (some folks say they culture their kefir in the refrigerator and say it works well- this isn't something I've tried yet)


As you learn to perfect the flavor of your kefir with the adjustments noted above, you will probably notice that the tartness is related to the consistency or thickness.

More fermentation = more tartness = thicker consistency (or curd and whey separation)

Fortunately, there is a second way to control of the consistency of your kefir, and that is by straining it. The process I use is really easy and requires only a coffee filter and a mesh strainer. And I can use it to make a probiotic-rich, delicious replacement for Greek-Style Yogurt, Sour Cream, Cream Cheese and Goat Cheese.  For step by step instructions, click here.

Optionally, you can also pour off the excess whey like I show in this video: Easy and Thicker Kefir


Place your grains in a jar with 2 to 4 cups of fresh milk, then seal with an airtight lid and place in the refrigerator to store for up to 3 weeks.


Rinse your grains with spring water, and lay them out to dry on a sheet of parchment paper. You may need to flip them every so often, but they should be completely dry in about 2 - 5 days. Once dry, seal them up in a zip-lock freezer bag with a little powdered milk and toss them in the freezer for up to 6 months.


When you are ready to wake them from hibernation, you will just remove the grains from the bag and follow the same process you would follow if you were culturing active grains. Place them in a jar with milk, cover with a coffee filter, and place in a warm spot (about 70-85 degrees F) to culture. The only difference is that you can begin with just 1 cup of fresh milk, and transfer the grains to fresh milk either as soon as it thickens, or every 24 hours max. As you begin to see results, you can begin to increase the milk in each successive batch by 1/2 cup until you get to your full batch size (4 cups max). It may take several rounds before the grains are producing kefir as quickly as they once were, but they should come back to you.