Freezing Kefir Grains
One method for storing kefir grains for periods of up to 2 months, is by freezing the grains. To freeze kefir grains effectively, wash the grains with pre-boiled then COOLED water, pat them dry between pre-ironed cooled white towel to remove excess moisture. Place the grains in a jar or in a plastic bag, with the addition of dry milk powder [do not add fresh milk or other water based liquids]. Add enough dry milk powder [DMP] to completely cover the grains, seal the jar or the bag and then freeze. DMP is added as a protective agent. Although I’ve found that kefir grains are viable for up to one year when using this method, this length of time may completely remove the yeast component found in healthy kefir grains [when frozen for longer than 2 months, but not specifically]. Because of this potential, freezing kefir grains as explained above, is best performed for a period of no longer than 2 months. If DMP is omitted with the kefir grains, then a period of no longer than 1 month is recommended. Otherwise the yeast component of kefir grains may become damaged, especially so if thawed and frozen due to poor freezing conditions or poor freezer mechanism of the refrigerator or freezer.