Introduction: How to Make Authentic Milk Kefir

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Milk Kefir (pronounced keh-FEER) is a wonderfully delicious slightly carbonated fermented milk beverage similar to yogurt (or buttermilk). Kefir is simply milk that is fermented at room temperature with kefir grains for about 24 hours. It has many wonderful health benefits, a great flavor and is also usually tolerated well by the lactose intolerant. It's much easier to make than yogurt - no heating or incubating involved, and kefir has a much larger spectrum of probiotics than yogurt. The reusable, sustainable grains also make it more economical.

Kefir has gained in popularity lately, due to interest in eating more responsibly and locally, as well as more economically, combined with a greater awareness of the health benefits of probiotics from cultures and whole foods.

But with that popularity has come a load of misinformation and deceiving products on the web. Authentic kefir can only be made by real kefir grains, not from any kind of packet or powder (or from incubating store-bought kefir). Kefir available at the stores are simply imitations. This is due to regulations on consistent products with known ingredients, bottling procedures and packaging and shipping standards. As with most nutritious foods, real kefir can only be made and experienced at home.

Milk Kefir originated roughly 2,000 years ago in the Caucasian Mountains between Europe and Russia, which makes kefir one of the oldest milk ferments in existence. If you have more questions you can check out Yemoos Nourishing Cultures to see photos, FAQ's, health benefits and other information on milk kefir.

Now, lets get started!

Step 1: Supplies

There isn't a whole lot you need. Milk kefir is quite a simple ferment:

A. First, you will need milk.

*Make sure the milk isn't ultra-pastuerized or 'lactose-free'. Raw milk is best, but if you don't have access to raw, simple basic whole milk works well. Skim or low fat milk will work, but the grains prefer the full range of nutrition found in whole milk. 

B. Second, you will want  a strainer on hand - fine plastic/nylon or stainless steel. Aluminum and other metals can leach when coming into contact with acidic liquids such as milk kefir. Stainless steel is considered safe for short term contact.

*Strainers with large holes (like pasta strainers) don't work well - the smaller grains may pass right through into your kefir drink, rendering it gritty and lumpy (and unstorable - it will continue to ferment quickly in the fridge). Though its not a health hazard to drink them, you will lose part of your culture.

C. As for the other supplies, you will need a bowl to capture your strained kefir, a jar and breathable lid to ferment your kefir in, and a jar or bottle for storing your strained kefir in the fridge. A sterile wood or plastic spoon is also handy to help strain the kefir. You may want to have some yummy fresh fruit or other vanilla extract on hand to flavor your kefir, though it is yummy plain, too! 

Step 2: Preparing the Kefir Grains

Now its time to prepare the little guys.

A. If you've just received your kefir grains in the mail, store them in the fridge until you are ready to feed them.

B. To prepare your grains, strain off and discard the kefired milk they are in. Sometimes they are 'naked' and thats ok too - either way, give them a quick rinse with spring water or a bit of milk if they've been in transit for a couple days. The easiest way to do this is to place them in a clean bowl with the spring water or milk after they've been strained and gently stir them to dislodge any cream stuck to them. Strain and repeat if desired. Do not worry too much about getting them pristine - a gentle rinse is sufficient.

Step 3: Feeding the Grains

Now that your grains are strained and gently rinsed, they are ready to be fed.

A. Simply place them in a sterile jar and fill with milk!

*Make sure the jar is big enough to have atleast a couple inches space between the milk and the lid. A quart jar typically works well. Also make sure there is no soap residue - antibacterial soap will damage the bacteria in the grains.

*A good ratio is about 1 teaspoon per 1 cup milk in the summer and 1 tablespoon per 1 cup milk in the winter (it simply ferments faster in the summer - more on this in later steps).

Step 4: Cover and Ferment!

Now your work is done, and the kefir grains' work begins!

A. Cover the jar with something breathable like a papertowel, coffee filter, dish cloth.

*Avoid cloth with large holes - you want something breathable but not something that dust or fruit flies can fit through.

B. Simply place the jar in a cupboard or other area that has a relatively cool and stable temperature. It does not need sunlight (which can heat it too much, anyways). Indirect light is ok.

C. Let it ferment about 24 hours. Read on to determine when it's done.

Step 5: Determining When It's Ready

To determine when it is done, barely tilt it and see if its still runny like milk, or slightly gel-like. When its gel-like, it's ready. It will ferment more quickly in the summer than winter.

*You may also see little pockets of clear liquid bubbles forming, especially near the bottom. This is the beginning of seperation of the curds and whey (curds=white part, and whey=clear part). This also indicates it's done.

As you can see the jar to the left is ready to strain and the jar to the right is considered a little past done ('over-fermented'), with a large amount of separation occuring.

Step 6: Straining Your Finished Kefir

Once the kefir is ready to strain (view previous step for how to determine this), you will want to bring back out your strainer, a bowl to capture the kefir in, a spoon to stir and a bottle to store it in.

A.Place your strainer over a bowl (stainless steel, wood or plastic -preferably with a pouring spout).

B. Simply tip the whole jar of kefir, grains included, into your strainer and let strain.

*You may notice the top is lumpy - this is normal - the grains usually float to the top at the end of the ferment.

C. It may strain slowly, if so, you can gently wiggle the strainer or use a sterile wood, plastic or stainless steel spoon to gently stir and encourage the kefir to strain through into the bowl, leaving the grains behind in the strainer. Don't worry, no matter how thick, it will all eventually get through.

*You may notice the clear whey straining first, followed by the thicker creamy white curd portion. Some people prefer to toss the whey for a more mild, thicker kefir. This is not necessary, and  you will also be discarding many valuable minerals and proteins found in the whey. 

Step 7: Bottle Your Kefir, Flavor and Repeat!

A. Once your kefir is strained, place your grains back into their jar. You can rinse or wash the jar if desired, but it's not necessary every time. Rinse or change jars once you notice too much build-up. The build-up can cause your kefir to ferment too quickly. 

B.Stir your strained kefir to smooth out any chunks and then enjoy! You can also bottle it to let it 'mellow' a bit in the fridge, which also allows it time to increase in B vitamins and folic acid (as well as carbonation).

*Store your kefir in tempered glass jars or bottles (designated canning or beer/wine bottles - which are less likely to explode) with atleast 1/2 inch of space between it and the lid. The carbonation build-up over time can lead to the jar exploding. To prevent this, you can store it with the cap on loosely, or simply 'burp' it once a day to allow any built-up air to escape (open the lid and close it again - this will not hinder the carbonation - it will still get carbonated).

*Mix in some fresh fruit, dried fruit, jam, honey, maple syrup, or extract (about 1 tsp per 1-2 cups) to up the yumminess! There are truly endless ways to flavor your kefir.

C.Now simply feed your grains fresh milk and repeat!

*If your kefir was over-fermented at 24 hours, increase the milk by atleast 1/2 cup. Or decrease the grains by atleast 25%. Store extra grains in a little milk in the fridge as back-up!

If you have more questions you can check out Yemoos Nourishing Cultures to see photos, FAQ's, health benefits and other information on milk kefir.