Fermentation has been used by human beings in every climate, for as long as we have been preparing food. And yet every season brings its own challenges, even in our climate-controlled homes. This is because we are dealing with living organisms, who are impacted by their environment as much as any other living thing. I hope the following give you a broad idea of how best to care for (and enjoy consuming!) your ferments through the hot and humid Ontario summer.
1. Sunshine: Though sunshine won’t generally do much to alter a ferment, summer is not the time to leave your jars sitting in a windowsill. Ferments can become overheated in direct sunlight, causing mushy or discoloured vegetables and possibly explosive jars. Keep your ferments where the temperature is predictable, and sunshine is indirect.
2. Air Conditioning: Turn it down! Cultures like kombucha and water kefir need some warmth to keep active. Kombucha especially will become imbalanced if it has to tolerate temperatures outside of 24-29 Celsius for too long. If you don’t like your home being above 24 degrees, consider closing the vents in one room and keeping your cultures there. Or you can purchase a kombucha warming mat and use this to keep a variety of cultures (like water and milk kefir, Jun, or yogurts) warmer than the rest of your home. On the plus side, fermenting veggies like to work at about 22 degrees, so if that is your A/C setting this may be your perfect season to pack away sauerkraut!
3. Exploding Jars: If you are working with beverage cultures in the summer, you will find that the fermentation time is shortened in the summer heat. Water kefir can take as little as 24 hours (rather than 48), and a second ferment may only need 12. You will notice your beverages become sour more quickly, and potentially more bubbly. You may also notice jars loosing their lids with all the extra pressure from building carbon dioxide. Worst case scenario, your jars will not be able to pop their lids and will instead explode. This can be very dangerous so be sure and work with vessels that can release extra pressure if needed. I have had good luck with glass jars that have pop-on, pop-off plastic lids. Others like to use bail-top bottles. If you’re wary, you can make a batch or two in a plastic pop bottle and notice how long it takes for that bottle to become hard (there is surely enough CO2 then!). Sometimes people keep their beverages in a cooler, to both regulate the temperature a bit and to be protected should any jars explode.
4. Messy Ferments: In the summer I notice that my veggie ferments are especially bubbly, juicy and active. This is also true of beverages; opening a new bottle can sometimes result in a very messy kitchen (think: opening a shaken pop can). Open fresh bottles and jars over the sink (aim the lid away from you), just in case those microbes are very excited to be out in the world! If you’re fermenting a messy jar of veggies, keep the jar on a tray or in a bowl to catch seeping liquid. Be sure and add extra salt brine to the jar following the fermentation period, should the liquid levels be too low after all that activity.
5. Ferment All The Things: Get out to farmer’s markets and let your imagination run wild on fresh combinations. Basil-strawberry kombucha? Garlic scape in your salsa? One of the beautiful things about making your own ferments is that you create a truly unique product, reflective of your own place and season. Go ahead and pick up those beautiful veggies you’ve always wanted to get but could never think of a use for – they could be your new favourite kraut ingredient!