By: Brew Your Bucha Posted: July 19, 2018 in Kombucha

So, you've finally joined the world of homebrew kombucha and you've got your starter tea going. After adding in your sugar, you're ready for the fermentation process. However, you notice that your room is much colder than room temperature, or maybe your room is too hot and humid? Some people may disregard this fact, but the room temperature has a huge effect on your final product. That's why we're here to give you all the facts about kombucha brewing temperatures.

How Fermentation Works

Much like beer or yogurt, kombucha is a product of fermentation. According to Khan Academy: "Fermentation is another anaerobic (non-oxygen requiring) pathway for breaking down glucose, one that's performed by many types of organisms and cells." In kombucha, the SCOBY contains a host of microorganisms that are hungry for glucose, aka sugar. When the SCOBY, starter tea, and sugar are combined and left to sit, this begins the fermentation process. The microorganisms eat the sugar in the brew, which in turns gives kombucha its wonderful flavour and carbonation. Without the microorganisms, the fermentation process can never happen.

Another factor in the fermentation process is the temperature. According to How to Brew: "The third factor for a good fermentation is temperature. Yeast are greatly affected by temperature; too cold and they go dormant, too hot ... and they indulge in an orgy of fermentation that often cannot be cleaned up by conditioning." Thus, it is crucial to have a good brewing temperature or the fermentation period and quality will be compromised. This is crucial for kombucha brewing temperatures.

Too Hot? Too Cold?

The ideal kombucha brewing temperature is room temperature, which is about 23 °C or 73 °F, which leads to a 7 day brewing period. However, if the room temperature is too hot or too cold, it can greatly affect the fermentation and final product. This is why it is crucial to place a temperature strip on your brew jar in order to keep track of your temperature. Fortunately, all of our kits come with everything needed to track your kombucha brewing temperature.

Bacteria generally love warmer temperatures and become more active as the degrees increase. Consequently, a kombucha fermentation in a room that is too hot will lead to a much quicker fermentation process. This can cause problems because it can be extremely difficult to control flavours if the bacteria work too quickly. In the case of kombucha, this can lead to kombucha that either tastes too sweet or, more commonly, too sour. This happens because the bacteria eat glucose quicker in warmer temperatures, which will make your kombucha taste more like vinegar.

If you find your room to be too hot, try to find the darkest place in your home to ferment. Moreover, you can wrap a moist towel around the brew jar and even use a fan to cool down your brew. Just remember to keep track of the temperature, so your brew doesn't get too cold.

On the other side, colder temperatures slow down microorganisms, which also slows down the fermentation process. Consequently, this can lead to a higher chance of mould developing in your kombucha, which presents some serious health risks. One solution for brewing in a cold room is to use an electrically heated blanket. Simply adjust the blanket to the desired temperature and place it under the brewing jar. This solution is great because the electric blanket does not carry much fire risk and can be adjusted to your desired temperature in conjunction with a temperature strip.

Finally, if you're brewing in a room that is either too hot or too cold, it is important to taste your brew to determine where it is in the fermentation process and adjust the times as needed.

Treat Your Kombucha like a Vampire

Much like a vampire, kombucha hates sunlight. Thus, it is crucial that you store your fermentation in a dark place devoid of any sunlight. According to The Probiotic Jar: "Lactic acid-producing bacteria (LAB) (the bacteria that do the work of fermentation) flourish in the dark, and light kills them." If you place your fermenting brew in direct sunlight, there's a good chance that the UV rays will kill the helpful bacteria, which will kill the fermentation process and lead to mould growth. If it is difficult to find a location that doesn't have any sunlight, wrap your brewing jar in a thick towel that can block any harmful UV rays.

We hope you're now an expert on kombucha brewing temperatures after reading our article. We strive to make the home brew process as easy as possible and have guides to help you through everything. Also, please visit our shop if you're interested in buying your own homebrew kit and jumping into the world of kombucha.