How To Make (Almost) Sugar Free Kombucha
High-fructose corn syrup! Obesity! Sugar kills! You’ll see a lot of anti-sugar hype in the media, and there’s a grain (or a crystal) of truth in almost all of the claims. In fact, there are many very good reasons to cut back on sugar consumption, ranging from the environmental and human impact of the sugar industry to the very real health risks created by eating too much sugar. However, as part of a balanced diet, kombucha shouldn’t be high on your list of sugar hazards, especially since there are so many other health benefits from drinking kombucha.
Natural vs. “Added” Sugar
There are natural sugars in many things, and there’s very little you can do to escape sugar entirely in your daily diet.
Sucrose is the type of sugar that other sugars are compared to. Most commercial sugar comes from the sugarcane plant, or from processed sugar beets.
Lactose is a type of sugar found in milk. It’s less than half as sweet as sucrose.
Fructose is found in fruits, especially very ripe ones. It’s as sweet, or sweeter than, sucrose.
Maltose is found in grains like barley, and is a form of glucose.
Glucose or dextrose is a type of sugar that comes from certain starches when they break down. Put a plain water cracker in your mouth and let it dissolve, and it will start to taste sweet.
Sucrose is a natural sugar, though most people don’t see it in its unrefined state. If you chewed on a piece of sugarcane you’d get much less sugar than you would if you ate a spoonful of refined cane sugar.
The real problem comes from added sugar, either refined cane sugar or something called “isoglucose” – another name for high-fructose corn syrup. This high-octane sweetener adds calories and leads to sugar spikes in your system, where your body cannot regulate itself. It’s not classified as an artificial sweetener, but it’s definitely made through an artificial process. You won’t find high-fructose corn syrup in corn, but you’ll find it on hundreds of thousands of product labels.
Kombucha uses sugar as food for the microorganisms in the SCOBY (Symbiotic Colony Of Bacteria and Yeast). If the microorganisms don’t have this food, they’ll die. There’s really no alternative. If you’re going to make kombucha, you’re going to have to use some sort of sugar that nourishes the SCOBY.
How Much Sugar Is In Kombucha?
Most people use cane sugar to make their kombucha. Of all the types of sugar used for kombucha it’s the easiest for the microorganisms to break down and process. Cane sugar is sucrose, which is a large molecule formed of smaller molecules of glucose and fructose. Most of the tests on kombucha measuring sugar content have been done on brews that used sucrose. There’s some variety in the results, due to the fact that every SCOBY performs a little differently, so every batch of kombucha comes out a little differently as well.
The longer you brew kombucha, the more sugar is processed. If you let the SCOBY work long enough, you won’t be able to taste any sugar in the tea, and it will taste just like vinegar. There are still some residual sugars, but not many.
Tests have found that there is as little as 1 gram of sugar in an 8-ounce glass of plain kombucha, while other tests show between 4 grams and 8 grams, depending on how long the kombucha is brewing. On average, there’s usually between 2 and 4 grams of sugar in an 8-ounce portion of commercially-brewed plain kombucha.
To put that into perspective, here are some 8-ounce drink comparisons, showing how much sugar they have on average:
24 grams unsweetened apple juice
22 grams soda/cola
12 grams 2% milk
11 grams orange juice
9 grams tomato juice
8 grams 1 whole apple
1 gram 8-ounce glass of PLAIN Kombucha
As you see, homemade, plain Kombucha is VERY low on sugar content, even less than FRUIT. Sure, if you buy a fancy flavored Kombucha from a store, it may be packed with more sugar. But PLAIN Kombucha is very low sugar and should not be feared.
NOTE: If you do have a problem with diabetes or any other health issue that requires you to follow a low-sugar or sugar-free diet, check with your medical provider if you have any questions.
How To Reduce Sugar In Kombucha
The yeasts and bacteria in the SCOBY primarily use glucose as their food. During the process of fermentation, the yeast converts most of the glucose into ethanol and carbon dioxide (CO2). The bacteria take the ethanol and most of the remaining glucose and transform them into probiotics and organic acids, plus nutrients like vitamin B6. The longer you ferment kombucha tea, the more time the SCOBY has to use up the glucose.
That means there are two ways to reduce sugar in kombucha: use glucose as your primary sugar source, and let the fermentation continue as long as possible.
1. Use Glucose and Fructose Instead of Sucrose
While sucrose does break down into equal amounts of glucose and fructose, the SCOBY mostly uses the glucose for energy, while the fructose contributes to the fermentation process. Much of the residual sugar in fermented kombucha tea is fructose. If you choose a sweetener that has more glucose than fructose, there will generally be less residual sugar in the tea. Here are some options:
- Regular (NOT high-fructose) corn syrup – 100% glucose
- Barley malt syrup – 70% maltose and 20% glucose
- Rice syrup – 50% glucose and 50% maltotriose (a form of glucose)
It’s a good idea to mix these sweeteners with some organic cane sugar, or another type of sweetener that contains fructose, so that the fermentation works properly. However, some people have reported making kombucha successfully with rice syrup alone.
2. Longer Fermentation
While the SCOBY is in the kombucha tea mixture, it will continue to convert the sugars into acids. If the process goes on too long, the tea might be too sour for you to drink. In general, your kombucha tea will reach its perfect sweet-tart flavor anywhere between 7 days and 30 days, temperature depending.
Kombucha that has been fermenting for two weeks at a room temperature of more than 78 degrees generally has very low levels of sugar.
But you can reduce the sugar even more. You can:
- Do a longer primary ferment
- Do a longer secondary ferment
- Do a longer primary ferment and secondary ferment
However, for the best taste with the least sugar content, I recommend doing a longer second ferment over a longer primary ferment or longer primary ferment + longer secondary ferment.
A secondary ferment kombucha will continue the process of converting the residual sugars in the tea. The advantage of doing a longer fermentation time at this second stage (vs doing it in the primary fermentation stage) is that the yeasts are more active than the bacteria, so the sugar will continue to be processed without a lot of added acid.
3. Try Different Sugars
You might be able to reduce the sweetness by substituting other sugar types in instead of plain sugar. For example, Molasses instead of sugar adds a nice nutrient boost and also containers LESS sugar than plain white sugar. You can try honey or even Corn Syrup (corn syrup is pure glucose and LESS sweet than table sugar…note, I refer to Corn Syrup, not HIGH FRUCTOSE CORN SYRUP). Read our guide to the types of sugars for Kombucha.
4. Don’t Add Fruit to the Second Ferment
Plain kombucha with nothing else added to it will have the least amount of sugar. Doing a second ferment where you add in fruit will add MORE sugar than will be contained in the first ferment (plain kombucha).
However, a secondary ferment does add more flavor and more carbonation, IF you add in fruit to it. You can reduce the sugar amount by extending the time of the second ferment to reduce the sugar levels added in by the fruit. It’s possible that if you second ferment the kombucha long enough, you can reduce the sugar to almost zero while keeping the fizz levels high. However, at this point, the booch will be quite vinegary with a fruit flavor, so this may be undesirable.
If you add fruit or doing a second ferment WITHOUT fruit because you don’t want the extra sugar, you can add something like cinnamon or ginger to help boost the carbonation levels without adding too much more sweetness. This gives you carbonation without the sweetness (or less sweetness).
The Final Word
It’s possible to reduce the sugar content in Kombucha, should you wish. However, keep in mind that DO IT YOURSELF Kombucha has less sugar than most other drinks out there! So you are not dosing yourself with dangerous levels of sugar — no more than eating an apple!
But for whatever reason, if you are scared of even the trace amounts of sugar in regular Kombucha, then you can reduce the amount by experiment with using different types of sugar, and with changing the fermentation time and/or doing a secondary fermentation after you remove the SCOBY.
One thing you’ll find useful is a sugar testing kit for kombucha. This will help you accurately track the change in the residual sugar level. Keep a notebook handy to record these levels, as well as your opinion of the flavor of the kombucha tea at that stage, and you’ll be able to brew the best almost sugar-free kombucha that your SCOBY can provide.