Keeping it HOT

By November 9, 2018August 12th, 2020No Comments

What is the big deal about keeping your kombucha brew warm? Lots!!

The temperature your Kombucha SCOBY is brewed at effects many things:

  1. Time – higher temperatures = brew faster
  2. Taste – higher temperatures = a sharper/more sour taste
  3. Mould – brewing at temps under 18C/65F has a much higher risk of mould
  4. Balance – since your SCOBY is a “symbiotic culture of bacteria and yeast”, the temperature also affects the long-term health and balance of the culture = higher temperatures produces more yeast.

I recommend brewing as close to 24C / 75F as possible. I feel this gives me the best attributes possible. Other brewmasters have other thoughts – everyone’s tastes are different! After you have mastered a couple of rounds of basic brews, I encourage you to experiment with extra Scobys. This way you can find what works for you, without sacrificing your main Mother Scoby.


Other considerations:

Many people turn down the household thermostat at night or while they are away.ย  So what can you do to keep your brew nice and consistently toasty warm?

As always, here are the low cost / no-cost options you can try:

  • monitor the temperature of your brew with the built-in thermometer on your kombucha kit
  • find a nice cozy warm spot (but not too hot) in your house, and brew there (the little cabinet above the stove works great!)
  • place your brew in the oven, leaving the oven light on sometimes will provide enough warmth CAUTION: Remember to remove your brew before pre-warming the oven for cookies or turkey dinner!!
  • wrap your brew in a warm towel or an old T-shirt
  • wrap brew up with a hot water bottle at night

Over the years I have tried out a variety of heating solutions here are the best choices I have found:ย  Rated worst to best.

Cooler Box1. Insulated box

  • picnic cooler orย grocery thermal bag or box
  • leave the box open to allow for fresh air to reach your brew
  • add a hot water bottle to keep warm overnight
  • ๐Ÿ™‚ reasonably priced
  • ๐Ÿ™ have to keep monitoring the temperature



Heat Lamp

2. Heat Lamp ( find on /

  • ๐Ÿ™‚ easily found at the local pet store or hardware store
  • ๐Ÿ™‚ reasonably priced <$30
  • ๐Ÿ™‚ some are adjustable
  • ๐Ÿ™ no temperature control – use a thermostat
  • ๐Ÿ™ fire risk



3. Home Brew Heat Belt (find on /

  • ๐Ÿ™‚ provides adequate heating to raise the temperature of approximately ~8-10 ยฐC
  • ๐Ÿ™ at 36″ long these belts are made to fit a wine or beer carboy, about 8 inches longer than you need for your stainless steel brewer.
  • ๐Ÿ™ no temperature control
  • ๐Ÿ™ not for use with glass, the heat is focused & intense which can break the glass



4. Seedling Heat Mat (click to shop karma cultures)

This is my preferred method.

kombucha heat mat

  • ๐Ÿ™‚ easily wrapped around 1-gallon jar or stainless steel brewer
  • ๐Ÿ™‚ standard length is ~21″ so wraps completely around 1-gallon jar
  • ๐Ÿ™‚ wraps ~8′ short on the stainless steel brewer allowing easy access to spigot and thermometer
  • ๐Ÿ™‚ provides adequate heating to raise the temperature ~8-10 ยฐC
  • ๐Ÿ™ no temperature control – use with a thermostat!
  • ๐Ÿ™ don’t place brewers on a seedling mat, heating from below increases yeast production and over time will disturb the microbial balance of your kombucha scoby



Kombucha Thermostat

6. Don’t Forget the Thermostat (click to shop karma cultures)

Probably the most important part of your heating system is the thermostat.ย  I don’t know about you but I don’t have the extra time to be checking in on my kombucha brew multiple times a day.ย  Using a thermostat allows the heat mat to turn on if the environment is too cool and off once it warms up.ย  Preventing overheating and losing the batch.ย  Take it from me, I learned the hard way.


Lea Ann Luchka

Author Lea Ann Luchka

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