Can I keep my active starter in the fridge in a big mason jar, loosely capped or ? I'm just looking for a way to store that's taller and skinnier in my small refrigerator!
Absolutely! You can use any jar that has been cleaned and rinsed thoroughly.
I store mine in a 1 qt mason jar. The lid has long since disappeared so I cover mine with a sandwich baggie and hold in place with a ponytail band (less unlikely to snap than a plain rubberband)
I used an empty Ovaltine jar. It's tall and skinny with a plastic lid. Just perfect for that purpose. Works for me. Al
I store my culture in a mason jar, I keep the top a little loose, and open it every 4-5 days just in case there is an excess build up of gas.
I store mine in old Ragu jars I've scrubbed out. Beats sending them to the landfill. I have three; rye, whole wheat, and white starters I've been cultivating for about a year. They seem happy and that makes me happy. I fed them very frequently in the beginning, like once a week, but got busy with other things and neglected them for months. I recently opened them, brought them to room temp and fed them again, and they came back to life. They're much more flavorful because of that long sit. I was worried about the build of acids from the bacteria killing the yeast, but it turned out fine. I keep them pretty liquid for ease of getting out of the jar, then I build them up in the bowl to a thicker consistency.
and even that's a bit oversized. I use a 10:20:20g ratio so just mixed, this 50g of starter takes up under 1/4 of the jar space. I feed it every couple of weeks, taking it out of the fridge, reducing to 10g and adding 20g of rather warm water + 20g of UAP flour, stir and leave it out for several hours until it at least doubles.
When it's reaching it's peak, it goes back in the fridge. If I get busy and it's started to collapse when I remember it, it goes for another feed. I want to cool it when it's at it's most active and there's still some food left, not when it's just waking up and just diluted or it's exhausted and eaten everything in the jar.