by spaceralph on Wed Nov 14, 2012 3:18 pm
I only refrigerate my culture when I have a surplus of finished kefir that needs to be used up, so yeah my kefir grains spend most of their time in a jar of milk on my counter top.
I have a two jar jar system that has been working well for me for over a year now. I am clean, but by no means sterile, about the process.
I culture the milk in one mason jar that pretty much lives on my counter and when the kefir is done I strain it into another jar that lives in my fridge. I always leave enough finished kefir in the jar on the counter to cover my grains, and I immediately top that jar off with milk to start the next batch.
I don't wash out either jar between batches unless they start to get a lot of gunky kefir build-up around the lid and/or rim of the jar.
The longest I have been able to go without washing the jars is about two weeks. I haven't had any problems with spoilage or mold, but in my situation after about two weeks of using the same containers the kefir tends to start developing a really cheesy flavor that I don't particularly care for. To me a drinkable yogurt type drink is good-- a drinkable cheese drink isn't so much.
Your environment is probably different than mine, so you may have to experiment a bit to see what works best for you.