WHAT ARE KEFIR GRAINS?
Kefir grains are symbiotic cultures of lactic acid bacteria and yeast. These have the shape of small cauliflowers up to 5 cm in size. They have an irregular shape and are slimy and soft to the touch.
Their color varies from white to pale yellow. Darker colored grains usually indicate worse health condition. When kefir grains are used to ferment non-diary milks, they can take on the color of the liquid in which they grow. Each culture is made up of a unique blend of bacteria, yeasts and other compounds as they will absorb bacteria from the surrounding environment, making them unique and different from each other.
For this reason, in addition to the final characteristics of the product, the fermentation times also vary from batch to batch. Some batch may be more prolific and rapid, others may take longer to ferment the same amount of milk. This fact is doesn’t indicate any problem with the grains, unless the change has suddenly happened.
POWDER STARTER CULTURES
There are artificially prepared powder starter cultures available. Although these cultures produce a kefir-like drink, they lack the biodiversity of true kefir grains. While kefir grains have a multitude of bacterial and yeast strains in them, commercial powders usually contain only few common probiotic bacteria strains and seldom have more than a single yeast strain.
Kefir grains aren’t expensive, so the only reason to buy the starter powder is that you wish to occasionally ferment kefir without having to worry about storing the kefir grains. In this case, however, I would recommend using commercial kefir as a starter. In this regard, you might be interested in the article: “How to make kefir: method from commercial kefir“.
Apart from the poor biodiversity, another disadvantage of using powdered starter is that they are limited to a single use. Healthy kefir grains often create new kefir grains during fermentation by multiplying. This doesn’t happen using powdered starter cultures instead.
Basically, if you want the real deal with all the associated health benefits, just stick to the traditional method using grains and look no further. You may be interested in the article: “How to make traditional milk kefir”
HOW TO STORE KEFIR GRAINS
Once you have your batch of kefir ready, you can either start the next one, or choose to store your grains to reuse in the future. Kefir grains can be stored in the fridge soaked in milk for a few weeks until you are ready to make a new batch. Or they can be dehydrated for long-term storage.
In this case you will need to dry the grains by laying them on a clean paper towel where they will air dry for 3-5 days at room temperature. Place them them in a container in the refrigerator for up to 6 months.
HOW TO REHYDRATE KEFIR GRAINS
To rehydrate the kefir grains you have previously stored, simply follow these steps.
First fill a small container with a cup of milk to add the grains. This container must be able to breathe and therefore secure on top with a rubber band a coffee filter or cotton cloth. Let the container sit at room temperature away from direct light for 24 hours. After this time you can filter the grains, discard the milk, and start the process again.
Repeat this process inreasing the amount of milk, the kefir grains will be active again when the milk thickens in the next 24 hours, maintaining a pleasant and slightly acidic odor. If the milk doesn’t thick within 24 hours, you need to repeat the process again.
When the milk thickens within 24 hours, you know your kefir grains are rehydrated and ready to use. Now you can safely drink the content and start your self-production all over again!