What Is Kefir?

How Kefir Is Made and How to Store It

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Kefir is a fermented milk product similar to yogurt. It has its origins in the Caucasus Mountains of Russia. This tangy, creamy milk product is sometimes referred to as the “champagne of milk” because of its fizzy effervescence. The natural carbonation gives kefir a light, foamy, creamy texture, even when made with low-fat milk.

How Kefir Is Made

Kefir is made from milk that has been gently heated to eliminate possibly pathogenic bacteria. Next, a specific mixture of bacteria and yeast cultures are added to the milk to begin fermentation. The unique mixture of bacteria and yeast give kefir its distinct flavor and texture. The starter cultures for kefir are often referred to as “kefir grains” as they look like small, lumpy granules, similar in appearance to cauliflower.

The bacteria Lactobacillus caucasius ferments lactose in the milk into lactic acid, which provides a tangy flavor. Saccharomyces kefir and Torula kefir, two yeasts used to make kefir, ferment lactose into a small amount of alcohol and carbon dioxide, which is responsible for the carbonation.

The yeast fermentation in kefir produces a small amount of alcohol. Most modern kefir-making processes result in kefir having 0.2 to 0.3 percent alcohol (about 0.5 proof).

The grains are strained out of the kefir before it is consumed. They are then used to start a new batch of kefir. As well, there is a powdered kefir starter that provides a specific set of bacteria and yeast. Commercial production may use a powdered starter to keep the taste consistent.

Yogurt vs. Kefir

Yogurt and kefir differ based on the type of cultures used to ferment the milk. Yogurt uses only bacteria, primarily Lactobacillus species, while kefir uses both bacteria and yeast. While yogurt can range in texture from a thick liquid to a semi-solid, gel-like consistency, kefir is primarily liquid.

Kefir is traditionally fermented at room temperature, and a family would let the milk ferment overnight. Yogurt is often fermented in a warmer environment.

Kefir Varieties

There are many recipes for kefir, which differ based on the specific bacteria and yeast used to ferment the milk and the type of milk used. In European countries, kefir is often made from goat, cow, or even camel’s milk. Most kefir sold in the United States is made from cow’s milk.

Plain kefir has a bright, tart flavor. To make it more palatable, many companies sweeten the kefir and add flavors like fruit or vanilla. Flavored kefir is closer in taste to yogurt and may be more easily accepted by those who are new to kefir.

Kefir can also be made with non-dairy milk, such as almond or soy. These non-dairy kefirs are made using the same bacterial and yeast cultures and offer the same probiotic benefits, making them an excellent alternative for vegan consumers.

How Kefir Is Used

Kefir is most often consumed as a cold beverage. Most people consume kefir because of its enjoyable flavor and texture. Kefir can also be mixed into smoothies, poured over cereal or granola, or used in baking.

Purchasing and Storing Kefir

Kefir can be found in most health or natural food stores in the refrigerated dairy section. European markets may also carry kefir. If you want to make your own, kefir-making kits are available in specialty stores or online. These kits provide the kefir culture “grains” and instructions on how to safely ferment your milk.

Because kefir is a fresh product with live cultures, it should be kept refrigerated. After opening kefir, it should be consumed within five to seven days.