My sourdough starter is like a beloved pet or houseplant. I made it from scratch almost 8 years ago and have kept it going through two cross-country moves, three states, and many lapses in bread-baking. When I go on a long vacation, making sure that it is taken care of — along with all my other fermented food projects! — is at the top of my vacation check-list.
Will It Need Attention While You're Gone?
The first thing to consider when caring for fermented foods while you're gone is whether you really have to. Think about where in the fermentation cycle your food will be when you leave, how long you will be away, and calculate whether it will actually need attention while you're gone. Many non-dairy cultures are just fine if left alone for a long weekend. Sometimes you can also fudge the schedule a bit and renew a sourdough or make a fresh batch of kombucha a day early so that it can be left on the counter while you're away.
If the length of your vacation pushes your usual fermentation cycle by a day or two, most non-dairy fermented foods will still be fine. Sourdoughs, kombuchas, and water kefirs will become a little more acidic than usual and will need to be refreshed promptly when you return, but they'll snap back into their normal fermentation habits just fine.
Stash It In the Fridge
If you're concerned about leaving your fermenting food on the counter while you're gone, consider stashing it in the fridge. Frequent or continual refrigeration can put a strain on yeast and bacteria cultures over time, but refrigeration can be a handy solution when going on vacation. Cool temperatures put yeasts and bacterias in a state of near-hibernation, pausing any fermentation activity. Sourdough, kombucha, water and milk kefirs, yogurt, and buttermilk cultures will all keep just fine for several weeks in the refrigerator.
To prepare your culture for refrigeration, refresh it just before leaving — refresh your sourdough, make a new batch of kombucha or kefir, etc. Cover the container and put it in the refrigerator. When you return, refresh it again and continue with your normal fermentation cycle.
Leave a Note for House-Sitters
If neither of these options sounds ideal for your situation, leave detailed care instructions for a house-sitter to follow, just as you would leave a note about watering plants or feeding pets. It's a good idea to go over the instructions with your house-sitter beforehand (or even better, give him or her a demonstration!), and leave any necessary ingredients out on the counter.
P.S. Even if your culture doesn't need any attention while you're gone, I think it's still a good idea to leave a note for your house-sitter! There's no greater sadness than returning home to find a house-sitter has dumped your sourdough down the drain in an act of kindness because she thought it was something rotting in the fridge.
I have the most knowledge of sourdough, kombucha, kefir, and yogurt, which all have regular cycles of care and "feeding." My advice here is drawn from tending those cultures. Cheeses, fermented vegetables, and other fermented foods may require different care instructions — I'd love to hear your experiences and advice!
Do you ferment your own foods at home? How do you care for them while on vacation?