How to Keep Kombucha Warm?

Did you know that nearly all issues that arise when brewing kombucha are temperature related?

best practices for keeping your kombucha warm

Kombucha Temperature

Did you know that nearly all issues that arise when brewing kombucha are temperature related? It’s true, that’s why it’s so important to have the temperature under control when making kombucha. When your brew is kept within the optimal temperature range, all the pieces seem to fall right into place. If you’re here, chances are, you’re fermenting outside the recommended kombucha temperature range of 75- 85 degrees Fahrenheit. The majority of kombucha brewers will have their kitchen colder than this at some point during the year. So let’s go over what happens at lower temperatures and the best ways to bring up the heat.

What happens when kombucha is too cold?

Slow Fermentation

Your SCOBY will be happy, balanced, and active when kept between 75-85F. But when the temperature lowers, the fermentation process slows down with it, and eventually to a halt if it gets low enough. When this happens, the first thing you’ll notice is your kombucha brew is taking longer to ferment than it should. Depending on the temperature, this can add days to weeks to your timeline. So you can’t expect the 7-10 day brew time often quoted when you’re not at the proper temperature. When the culture stalls, the fermentation stalls and the acidification of your brew stalls too. Without this added acidity protecting your batch, it becomes at risk for mold, which leads us to problem number two.

Mold Growth

Adding kombucha starter tea to our kombucha brew inoculates it with our culture of bacteria and yeast. The starter tea is acidic, so it also lowers the pH. The starting kombucha pH of 4.5 or less is required because it is too harsh for undesirables to survive, warding off harmful pathogens. As kombucha ferments, the pH continues to drop, making it more acidic. When the kombucha culture is under stress, the acid levels do not increase as quickly as they should. This makes your brew more likely to develop mold. This is why we say cold equals mold. 

Kombucha Heating Pad - Keep Your Kombucha Warm

How Do You Know If Your Kombucha is Too Cold?

Much like me, kombucha loves warm weather. Depending on where you live, room temperature may be lower than the ideal kombucha temperature. So the first thing you’ll need is a thermometer to take a temperature reading. We highly recommend this strip thermometer. These strips are adhesive and stick to the side of your brew jar. Once attached, it will provide a continuous temperature reading. This will allow you to monitor your temperature and make adjustments accordingly. 

My Kombucha Brewing Temperature is too Cold

First, and probably the best option, is to purchase a kombucha heat pad. This is a permanent fix and isn’t too inexpensive. Especially when you take into consideration how much money you’re saving by brewing kombucha at home. These kombucha warmers are gentle but efficiently warm your kombucha so it can live its best life. For maximum heat, these mats are wrapped around your brew vessel and secured with a band. For less heat, you can place the heat mat flat on a surface and then place your fermenter on top.  

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Tips For Keeping Your Kombucha Warm 

  1. Use a kombucha heating pad.
  2. Place your kombucha brew on top of a warm appliance, like the refrigerator.
  3. Relocate the brew to the warmest spot in your house.
  4. Remember, heat rises. Try placing your brew in a high spot in your house, like on top of a cabinet.
  5. Wrap your brewing vessel in a towel and place it in a warm location. Add a bottle of hot water for additional warmth and change as needed.
  6. Place your kombucha vessel in the oven with the oven light on. The oven light will create heat. Monitor the temperature and turn off the oven light once the desired temperature is achieved, do not leave it on or forget to turn it off. 
  7. This list wouldn’t be complete without including Christmas lights. Wrapping your jar with Christmas lights is another DIY option we’ve seen over the years. I’ve never tried this personally, so I can’t personally recommend this method as effective or safe. But it’s said to bring the batch up a few degrees. This method will not bring up the heat drastically, so this won’t work for really cold houses. But for mild or temporary cold snaps, some use this option.

Have a question or know other kombucha warming techniques? Please leave your comments in the section below. 

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