One of the main differences between a beginner kombucha brewer and a master brewer is the ability to control and understand temperature.
Similar to home brewing beer, kombucha yeast will thrive at a specific temperature. The longer your brew sits at this temperature the higher quality kombucha you will produce.
The trick is learning what this temperature is, and how to keep your brewing vessel at this temperature.
So, what is the best temperature for kombucha?
Through my experience, and a fair bit of research, I’ve found the best temperature to brew kombucha is 75°F. This temperature is optimal for the right amount of yeast growth. It produces perfect kombucha every time.
However, there is range of temperatures you can brew at. You’re just going to get a different quality of kombucha at each difference temperature.
How Temperature Effects Kombucha
Yeast love to be at a certain temperature. When they are below that temperature, they produce less food for your healthy probiotic bacteria to feast on. When above, they tend to run rampant and turn your brew sour.
The trick to becoming a master kombucha brewer is to know how to keep your brew as close to 75°F as possible.
As you can see in the graph above, the longer you brew your kombucha at a higher temperature the more acidic your kombucha will be. Your brew temperature will dictate:
- Brew length
- Kombucha flavor
- Carbonation
- Mold protection
Let’s keep it simple: the higher the temperature, the less time required for your brew. This becomes particularly important in the winter months if you have become used to brewing during the summer.
As the temperature directly controls the yeast production it, therefore, plays an important role in getting the right carbonation.
Keeping both your main brewing vessel, as well as your fermenting bottles at 75°F drastically improves your chances of getting that carbonation everyone is looking for.
Pro Tip: use a kombucha heating wrap during your F2 to get the best carbonation possible
Keeping the kombucha within the golden temperature range also prevents mold from developing.
The first thing I ask when people come to me with mold issues is “what temperature do you keep your brew?” More often than they say they are unaware.
Brew temperatures below 70°F produce weak yeast which results in weak bacteria. If the bacteria isn’t strong enough to produce the protective acids (which lowers the pH) then your brew is wide open to any sources of mold.
Keep your temperature above 70°F!
Brewing Kombucha Above 75°F
Some people I know like to brew closer to 80°F. This tends to produce a ‘thicker’ kombucha that is more tart compared to sweet.
As warmer temperature produce more yeast the brew tends to be more yeasty compared to a lower temperature.
Simply because there is more yeast to break apart the sugar you’ve supplied and turn it into glucose for the bacteria to feast on. The more the bacteria feast the more they will produce healthy acids.
Pro Tip: the best way to control your kombucha temperature is by using a purpose-made kombucha heat wrap.
If you prefer a thicker, full-bodied kombucha, I recommend brewing between 75°F and 85°F.
Your temperature will also impact the length required for your brew. The higher the temperature the shorter the brew cycle.
This is why so many people have problems brewing during the winter months. If you try and grow your own SCOBY, or try to start to grow another mother without having the right temperatures chances are you will fail.
Brewing Kombucha Below 75°F
If you prefer a lighter kombucha that is more on the sweeter side then you can brew your kombucha between 70-75°F.
Your yeast will be less active and will produce fewer byproducts for the bacteria to feed on. Fewer bacteria mean less healthy acids. It also means light, crisp tasting kombucha that is nice and sweet.
I usually tend to brew within this temperature range during the summer. I find it blends very well will fruit such as strawberries and blueberries.
What Is The Maximum and Minimum Temperature You Can Use To Brew Kombucha?
While the ranges I provided above are safe for brewing kombucha you should avoid brewing too hot or too cold.
The maximum temperature yeast can handle is 95°F. While this temperature won’t kill the yeast, it will stop the fermentation process. This is exactly what you don’t want for your brew.
On the other hand, the minimum temperature you want to be brewing at is 65°F. Brewing below 65°F produces weak fermentation and leaves your brew susceptible to mold and other foreign invaders.
This is why brewing in the winter can sometimes be troubling. This is usually when most home brewers develop mold. This is also when using a kombucha heating wrap is critical.
If you want to brew a safe kombucha with the correct pH you’ll need to have some sort of heating.
How To Control Your Kombucha Brew Temperature
The best way I have found to control the temperature of the brew is to use a purpose made kombucha heating wrap.
Other people have tried seedling mats, but whenever I have tried these they always increase the temperature beyond 80°F. Most of them also don’t have temperature switches.
Without temperature switches, you can’t correctly control the temperature for different seasons.
The mat I use provides just enough space so I can monitor the temperature gauge. Otherwise, I was constantly removing the mat to check on the temperature.
Other Methods Of Controlling Temperature
Another popular way of controlling the temperature of your brew is to use non-LED christmas lights. Plug your lights in and wrap them around your brewing vessel.
This can be a quick fix until you get your hands on a regular kombucha heating mat.
Other people have tried using home heating pads that are meant for heating your body. However, I do not recommend this option because of the potential contact with liquid.
These home heating pads are also usually much too hot for kombucha – even at the lowest setting.
How To Cool Your Kombucha
Occasionally, I hear about a kombucha brewer who has a hard time keeping the brew around 70°F.
The best way to keep your kombucha cool is to keep it in a dark cupboard away from any sources of heat.
Sources of heat include the sun, your oven, the fridge, or any other appliance.
If you still can’t manage to keep your brew cool then you can always try placing your kombucha near your A/C source or placing your kombucha inside a cooler with a little bit of ice.
Conclusion
The best temperature to brew kombucha at is 75°F. If you are 5°F off it’s not something to lose sleep over. The easiest way to keep your brew at this temperature is to use a kombucha heating wrap.
Be careful not to go outside of the temperature ranges of 95°F and 65°F – this is the best way to ruin your kombucha brew and potentially harm your health.
Any questions please leave them in the comment section below!