How to Increase Fermentation Time
Is your kombucha fermenting too quickly? In this post we take a look at how to slow the the rate of fermentation in kombucha - to get a more delicious full bodied kombucha.
Kombucha’s fermentation time can vary widely – from anywhere between a week, up to a month. The amount of time it takes for kombucha to reach a mature level of fermentation (not vinegar, just to the point where it has fully cultured) depends on various factors.
Longer fermentation times are usually preferable to short fermentation times. Long and slow ferments tend to produce better flavor profiles and a more consistent level of carbonation. They are also thought to encourage a wider range of probiotic elements.
If you are finding that your fermenting kombucha is reaching maturity faster and faster – then it might be a good idea to take some measures to slow it down.
3 Ways to Slow Down Your Kombucha
Here are the three main methods which one implement to slow down the fermentation rate of your kombucha.
Lower the Temperature
One of the main causes of overly fast fermenting kombucha is high temperatures. Kombucha can be brewed within a temperature range of 69-84 degrees. However it does best between 76 – 78 degrees. Fermentation is apt to speed up in direct relation to the temperature in which it is taking place.
Therefor this is the first aspect to check on if your kombucha is on fermentation overdrive and souring too quickly.
How to Lower the Brewing Temperature of Your Kombucha
Finding a Cooler Place for Your Brewing Kombucha
If the temperature is not excessively hot, merely a little on the high side – changing the position of your brewing kombucha might be the only change needed. Look through your home for a nice cool place. The back of houses and apartments (where the sun does not reach) is usually the coolest. However there might be other spots, such as on a stone slab in an area which gets ventilation.
Just make sure that the place you select is clean and free from dust and insects. Kombucha also needs oxygen flow, so do not lock it up in a cupboard.
Cooler Box + Ice Packs
If the temperatures where you and your kombucha live are excessively hot, then you might need to consider this method. If not all year round, maybe just in the hottest part of the summer.
Freeze some cooler packs or plastic bottles of water. Place your kombucha into an icebox, along with the freezer packs/bottles. Make sure that these do not touch the brewing vessel. Place the lid on top, but leaving a crack for airflow. You might want to have a double up quantity of ice packs / water bottles. This way you can freeze half, while the others are cooling the box – and then switch out and repeat.
For more info on cooling down kombucha, check out How To Brew Kombucha In (Very) High Temperatures
Reduce the Yeasts
The yeasts are the next thing to look at. An overabundance of yeasts can easily send a batch of kombucha into fermentation fast track. Over active yeasts usually occur in warm temperatures, so the two can go hand in hand to stimulate fast fermentation. However, even without excessive highs in temperatures, the yeast component of your kombucha can grow to a point where it is out of balance to the bacterial part of the SCOBY.
This will be easy to spot, as the yeasts manifest themselves as brown strings which hang off of the SCOBY, or float free. They also form particulate and brown sediment.
How to Reduce Yeasts
There are a couple different ways in which you can drop the yeast numbers
- Pull off of the SCOBY and remove from the kombucha any long brown strings.
- When setting up a new ferment, take starter liquid from the surface of its storage container. Free floating yeasts and yeast particulate will accumulate at the bottom. The top portion of starter liquid will contain the fewest.
- Filter your starter liquid. If your starter liquid is thick with sediment – then the best option is to filter it. You can use the methods outlined in How to Filter Your Kombucha to Remove Yeasty Stuff
and How to Remove Particulate from Kombucha.
Thin the SCOBY
Another factor which can contribute or cause overly fast fermentation is too much SCOBY in relation to sweet tea. In the beginning one waits eagerly for one’s culture to thicken and grow. However all too fast it can become a real fatty, and take up a good portion of your fermentation vessel!
If this is happening, then the best thing to do is to split the SCOBY.
How to Split a SCOBY
Remove the SCOBY from the fermentation vessel. With a clean and sharp knife, slice off of the top the portion which you wish to keep. The top of the SCOBY is the newest and freshest with the most vitality. The bottom is the oldest and contains the most dead matter.
You will probably find that the SCOBY has predefined layers to it. Cut along one of these layers, and you will probably not have to do much in the way of energetic slicing.
For more detailed info on spitting SCOBYs, check out How To Divide A SCOBY (Remove Baby from Mother)
Adjust the Sugar
Sugar can also play a role in the rate at which kombucha ferments. Too much sugar can cause problems, both over fast ferments, and completely stalled ferments! Too little sugar is also not good. Check to make sure that you are sticking to the standard ratio of 1 cup of sugar to 1 gallon of tea.
Overly fast fermenting kombucha is not desirable as it can yield up flat, flavorless kombucha that has a shallow flavor profile and reduced levels of probiotics.
If you are experiencing this, then it is definitely worth while taking steps to slow down your ferments.
Starting with temperature, check to see if your kombucha is brewing in a ideal range of temps. If not, the first thing to do is to try to rectify this. Cleaning out any excessive yeasts will also go a long way to getting your ferment back into balance. And if your SCOBY is super thick – thin him down!
As a last check, make sure that your sugar to tea ratio is correct. It is easy to dump in what you roughly think is the right amount – but discrepancies in this ratio can throw out the rate of fermentation completely.