How to Safely Store Your Kefir Grains
If you have healthy kefir grains they will be continually growing multiplying as they feed on their food source, either milk or sugar water.
It is always fortuitous to prepare for any catastrophe so you can store extra grains for various periods using a number of methods.
These methods, besides creating an emergency ‘backup’ should you need new grains, are also useful if you are going away on holiday or wish to take a break for whatever reason from kefir production (i.e. pausing your kefir production).
#1: Store Kefir Grains by Refrigerating Them
You can just tell kefir grains to “Cool it!” and pop them in the refrigerator. Place them in a clean lidded container with 2-4 cups of quality milk to serve as their food while chilling. Cold temperatures slow down the culturing process in general so by storing them in cool temperatures they will become less active. They should remain healthy, chilling for periods of up to 3-4 weeks in your refrigerator.
How to Reactivate Refrigerated Grains
The healthier your grains were before you put them in the refrigerator, the quicker they will reactivate when back in warmer climes. Add the previously chilled grains to quality milk 2-4 cups depending on the amount of grains and leave overnight, strain, replace with fresh milk and repeat until the grains are back up to speed. This could take a few batches but so long as the milk smells clean and sour you can utilize it even thought the probiotic powers may at first be reduced.
#2: Store Kefir Grains by Freezing Them
One of the simplest and most effective methods available to most of us is to freeze the grains – milk and SKG. Freezing should be suitable for at least two months storage and possibly even longer although it is better to err on the side of caution and replace those in storage every couple of months.
To prepare them for freezing, rinse the grains thoroughly in boiled and cooled water. Strain any liquid off, and pat dry between absorbent lint free material that has been sterilized with a hot iron or a clean absorbent paper towel. As a warning, the reason we dry as much liquid as possible is that any remaining water molecules expand on freezing and may damage many of the live organisms. Place the grains in a clean sealable container – a glass jar with lid or a ziplock plastic bag. With milk grains it helps to cover them completely with dry milk powder as it dries up any moisture but keeps the grains surrounded by a suitable medium that protects them from freezer burn.
The yeasts are more at risk if you freeze them for longer however they have been reconstituted and used even when frozen for over a year. It is just best to err on the side of caution but the quality of your freezer will have some impact on longevity too.
How to Reactive Frozen Kefir Grains
When you wish to reactivate frozen kefir grains, thaw them in the refrigerator or place them in a glass of cold water for a few minutes to soak then wash them in a sieve to remove any of the milk powder that may be sticking to them. Now they should be ready to start feeding again on either milk or sugar water.
In the case of milk kefir add milk a volume ratio of 3:1, milk:grains and strain and replace the milk every 24 hours, regardless of whether you think the grains are reactivating. Do this until you feel the milk has completely coagulated in the 24 hour period you can rest assured they are back up to speed, hungry and fermenting as they should. Your nose should also assure you with a clean sour odour that may be slightly yeasty.
Your grains may take up to a week to get back up to speed, perhaps even a little longer in cooler temperatures so be patient. Gradually increase the amount of milk the grains are fermenting until such time as you are happy with the amount of kefir and the grains may start increasing in volume again. There are variables in this so adjust time and milk factors to allow for differences.
#3: Store Kefir Grains by Dehydration
Dehydrating grains allows them to be deactivated and stored for up to a year and a half under the best conditions.
Prepare the grains by rinsing them well in pre-boiled then cooled water and drain. Pat gently to remove excess moisture then spread them out to dry on a suitable fabric like nylon or parchment paper. Cover with another layer and secure the edges to ensure no dust or insects can contaminate the drying grains. It is best if air is able to circulate above and below and they are in a warm drying environment so the process should only take 3-5 days maximum. SKG will dehydrate faster than milk grains. You could use a dehydrator but ensure the grains do not become heated above 85°F.
Once completely dry place the dehydrated grains will be quite brittle so handle with care. Place them in an airtight container, a ziplock plastic bag or a jar are suitable, and place in the refrigerator. Milk powder can also be added to milk grains to add a protective surface coating.
To be on the safe it would be wise to replace dehydrated grains every 6 months although they may in fact remain viable for much longer.
Reactivating Dehydrated Kefir Grains
Place the grains in a clean container and add either fresh milk or sugar water to let them soak and slowly reactivate. Replace this milk or sugar solution daily regardless of how much fermentation is showing. When the milk/water kefir starts to produce a clean sour aroma you can build up the amount of liquid back to the normal amount for each batch. This reconstitution process will most likely take a minimum of 4 days but could take up to a week and half.
Over the first days the milk may look and smell odd because of the initial yeast activity which may be stronger than the bacterial activity. As the symbiotic culture settles down it will return to the familiar texture and smell of healthy kefir which could take a couple of weeks of continual batches. After some weeks remove any brown crumbly grains as these will never again be effective kefir producers.
The Final Word
So there you have some tried and true methods to store your kefir grains for whatever reason. We hope it’s not long before you get them out of storage and back in action soon!