Yes, feel free to halve the recipe.
It is OK to use frozen berries or fruit.
YES, you can get by with two 2-quart mason jars ( instead of 3). Strain one of the kefir jars into a pitcher, temporarily, rinse out the mason jar, add the fruit to this one, and pour in strained kefir water form pitcher and 2nd jar. Get it? 😉
Adding the lemon helps prevents kahm yeast, and the prune really adds flavor and helps with fermentation.
Kahm Yeast: If you see a white yeast on top of your second ferment, it is most likely kahm yeast. It’s harmless but can affect the taste. If you have Kahm yeast, make sure to rinse your kefir grains in pure clean water before storing in a clean jar with no soap residue. Cover with clean water and feed. This should hopefully prevent it from coming again. Make sure to add Citrus to your kefir water. Make sure all jars are clean. Leave less headroom at the top of the jar for oxygen to get in, during the second fermentation. Rinse your fruit before using, this can introduce the yeast. Sometimes it can grow if the environment is too warm.
How to maintain/grow your kefir grains:
The kefir grains that you strained out earlier can be stored in a smaller 8-ounce jar, in the fridge in the extra water kefir you will have after you merge the two jars into one. Add more water to fill and 1 tablespoon sugar.
- When refrigerated, you want to feed the grains at least once a week, to keep them healthy and alive. They are happiest when they are actually making water kefir, so I just make one jar a week.
- If you want to make kefir water more often (or grow the grains faster so you can give some away) you can leave them out on the counter, feeding every two days.
- Feed 1 cup kefir grains with 1 tablespoon sugar, in 2 cups water, in the fridge once weekly. Feel free to change out the water every 2-3 weeks.
- The colder they are kept, the slower they will metabolize the sugar. The warmer they are, the faster they will metabolize the sugar- and will need to be fed more often.
- You can tell if the grains are “hungry” by tasting the liquid- if it is not sweet, but tangier, they are probably ready to be fed. If the water is sweet, they are not hungry and do not need to be fed.