Your cultures (kefir, kombucha, sourdough, and water kefir) are all living organisms and need to be cared for just like a pet. I love them like family, and have found ways to take care of them when I go on vacation. The good microbes in the cultures eat the sugars out of the culture, and you want to be sure they have plenty to eat so the culture won’t die. It is a living colony of microbes and needs food, just as you do. Here are the cultures and how you can store them for limited amounts of time.
Storing kefir grains for a week: Place your kefir grains in milk. If you have 1 tablespoon of grains, store them in at least 2 cups of milk, 3 is better. I like to make sure that they have plenty of food to eat. If you have more grains, add more milk accordingly. Then you place this in the refrigerator. This will last for one week. Coming home: When you return home strain off the milk that the grains were resting in and discard (you can also give this to pets!) and put them in new milk to make kefir. The grains will be a little slower making kefir when you first take them out of the fridge. The cold slows them down a bit, but the second time you make kefir they will be back up to speed.
Longer than a week: If you’re going to be gone for more than one week, then I recommend you freeze them in milk. Store them in a jar in the amount of milk you regularly use, leaving a little room at the top for expansion when it freezes. Store in a glass or food-grade plastic jar with a lid and place in the freezer. You can store this for several months and they should be fine. They will take a little while to wake up when you remove them from the freezer, but once they thaw, strain them and give them fresh milk After a few days of making kefir, they should be fine. You will need to discard the milk they were stored in. Freezing kefir grains should only be done once in a while. Freezing and thawing them continuously can diminish or kill them, but once or twice a year should be fine.
Storing SCOBYs. You can store extra SCOBYs in a jar with a lid in starter tea (from the previous batch) using enough tea to cover the SCOBYs. Place on your counter for up to a month. Check out the SCOBY hotel!
Storing your sourdough starter for longer. Dehydrating your starter for longer storage is the best way to make sure you always have a sourdough starter. Check out this recipe for details on how to dehydrate your sourdough starter.
Storing water kefir for one to two weeks. Prepare a sugar-water solution: for each 1/4 cup of water kefir grains, you will need to use 1/4 cup of sugar and one quart of water to make your sugar-water solution. (Just as you would if you were making a new batch).
If you have more grains, adjust accordingly by adding more sugar and increasing the water. So for instance, if you have 1/2 cup of grains, then add 1/2 cup of sugar and increase the water to 8 cups and so forth.
Place the grains in the sugar water, place a tight lid on the container, and place it in the refrigerator. This will keep for at least 2 weeks in your fridge.
Longer than two weeks: If you’re going to be gone for longer than two weeks, double the sugar. (No need to double the water.) When you return, strain your water kefir grains and discard the sugar water solution they were in, giving them fresh sugar water to make a new batch of water kefir. Your grains will be a little sluggish but after a few feedings, they will be up and working again. Giving them a little bit of molasses also helps (1 – 2 tablespoons per jar is perfect) and will keep your water kefir grains really happy!