Kombucha brewing in different seasons

If you’ve brewed kombucha consistently over a period of time, you may notice that your brewing cycle (or how long it takes for your brew to ferment) can change as the seasons change. This is because temperature plays a big role in the fermentation process. For my in-depth post on temperature, definitely give that a read here

The ideal range for fermenting kombucha is between 73-78 degrees F. But we obviously can’t always ferment in that perfect range, so in this post, I’ll cover what to expect and how to prepare for brewing in colder and in warmer temperatures.

Winter & Cold-Weather Brewing​
  • Fermentation takes longer: During winter months, you’ll typically find that it takes longer for your brew to ferment because low temperatures can make yeasts and bacteria less active. While average brewing length can vary from person to person (and from culture to culture), my batches typically take between 7-12 days to ferment at around 75 degrees F. But in the wintertime when temperatures drop to the high 60s, it can take two weeks or more for my batch to acidify.

  • Brews could use an extra dose of starter tea to boost immunity: Even if it takes longer for your brew to ferment, you don’t need to worry about it as long as it doesn’t get moldy. To help safeguard my batches from mold, I like to use 3 cups of starter tea per gallon batch (instead of 2 cups) when the weather turns colder. This helps give my brew an extra dose of good bacteria and yeast — basically giving it an extra immunity boost.

  • SCOBYs can be paper-thin or new SCOBYs may not grow at all. Sometimes, cold temperatures hinder new SCOBY growth. This is completely normal. SCOBY growth won’t tell you when fermentation is complete. At best, it’s just an indicator that fermentation is happening, but fermentation can still be happening without SCOBY growth. SCOBY size/shape doesn’t matter as long as the liquid is acidifying. The best way to tell when your brew is done is to taste it. Read more about that here

  • Longer fermentation times can lead to bland kombucha. I generally find that in colder months, when my brews take longer to acidify, the flavors tend to be a bit more muted and bland. I offset this by flavoring with bolder fruits and increasing the amount of flavoring I use in second fermentation.

Summer & Warm-Weather Brewing
  • Warm temps = faster fermentation. As average room temperature increases, you may find that your brews acidify much faster than they usually do. Sometimes in the summertime, my brews only take 5 days to reach the level of acidity I like. To make sure you don’t miss that sweet spot (and to ensure your brew doesn’t get too vinegar-y), just taste it earlier and more often so you can flavor/bottle it before it gets too sour.

  • Use less starter tea if your brew ferments too quickly. If you find that your batches get too sour too quickly, use 1 cup of starter tea per gallon batch instead of 2 cups.

  • Faster fermentation can lead to overly-yeasty or over-acidic kombucha. While this doesn’t affect how healthy the brew is (it’s still safe to drink regardless!), you might find that brews that ferment quickly develop an astringent or overly yeasty flavor. You can offset this by using less starter tea or by masking the flavors during second fermentation with sweeter fruit juices or by adding more sweet tea.

​© 2020 by You Brew Kombucha

Disclaimer