Kombucha comes from ‘Kombu’s cha’, with Kombu reportedly being a Korean Doctor who used his tea drink to help with a stomach complaint. It reached Russia around the 20th century and became a popular household beverage.
It consists of a fungal disc, also known as a SCOBY – Symbiotic Culture Of Bacteria and Yeast – Symbiotic referring to the bacteria and yeast strains living together in a complex, mutually supportive way. During the fermentation and oxidation process, it feeds on the sugar and in exchange, produces valuable substances such as gluconic and glucoronic acids, acetic and lactic acids, B vitamins, amino acids, yeasts, bacteria, antibiotic substances and other nutrients. Glucoronic acid plays a big role in detoxification, with the other substances providing other health promoting properties such as probiotic effects and the regulation of gut flora, cellular strengthening, pH balance and metabolic balancing.
How to make your own Kombucha
Loose or teabags of black or green tea
One 2L glass jar to make the tea
One 1L jar for the fermentation process
Glass bottles to decant the kombucha
* see FAQs for the best materials to use.
1. For a 1 litre container of Kombucha, boil about 620ml of water and pour into a glass jar. Infuse 1.5 tsp of black/ green tea or 2 teabags for 15 minutes.
2. Strain off the tea leaves through a sieve or remove the teabags after 15 minutes.
3. Then add the sugar*. Do this before the tea has cooled so the sugar dissolves completely.
* For a one litre container, use about 60g of sugar (1 tbsp is approx. 20g). It is tempting to use less sugar than called for, but don’t as this can disrupt the fermentation process and potentially result in a tea that is unsafe to drink. At the conclusion of the fermentation process, kombucha should only contain 1 to 2 grams of sugar or less per cup. If you want less than this, ferment the kombucha for longer.
*See FAQs for which sugar to use.
4. Let the sugared tea cool down to a temperature not higher than 20-25’C (lukewarm) before adding the culture to the tea, as the culture can die if placed in too hot a solution.
5. When the tea is cooled, pour the solution into your glass jar that you will use for your culture.
*If preparing your first kombucha drink, add the liquid that you got with your culture (about 120ml for a 1 litre container). On all later batches, always keep enough Kombucha to add to your new batch as a ‘starter’ liquid. Approximately a tenth of the quantity is sufficient.
6. Place the culture into the tea and cover the mouth with the muslin cloth and tie it down with a rubber band. This keeps out fruit flies, dust, plant spores and other pollutants. It however needs to be porous enough to allow air to circulate so the culture can breathe but not too much that flies etc. can get in to lay their eggs.
7. Place the jar ideally in a warm, dark place where the temperature will not drop below 20’C. The ideal temperature is 23-39’C. Try to avoid exposure to bright sunlight as the culture could become damaged.
8. Fermentation* takes about 8-12 days depending on the temperature. The higher the room temperature, the quicker the fermentation. It also however depends on taste. If you like it quite sweet, ferment it for less; and longer if you like it sour, as the sourness means that the sugar has been broken down.
*During fermentation the sugar is broken down by the yeast and converted into CO2 and various organic acids and other compounds. It is the combination of these processes which gives the Kombucha its characteristic flavour. It is at first sweet, but as the sugar is broken down an acid flavour begins to develop as a result of the bacterium activity.
9. When the tea has attained the correct taste, pour the liquid into a glass bottle* (ensuring that you leave a tenth still in the jar for the next batch). Fill it to the brim and secure tightly.
*It is not necessary to strain the fermented tea as a certain amount of sediment is normal. The residue is also a result of the yeast growth which is said to have a desirable effect on the body anyway.
10. Allow it to mature for at least 5 days in a cool place, after it has been bottled, to produce an effervescent drink.*
*The activity of the bacterium is stopped when bottled, as it excludes the air, while the yeast continues to work. Therefore, when stoppered securely, the gas produced by the yeast’s activity is unable to escape. This produces the effervescence.
NB: Do keep an eye on it though as the pressure could cause the bottle to break, so release the pressure a couple of times over the 2 days.
11. The drink should be sparkling, slightly sour and refreshing. It is recommended to have one glass first thing in the morning on an empty stomach; the second after a meal during the day; and the last glass shortly before going to bed.
12. Remove the culture from the jar with clean hands and clean the culture. Place it back in the jar with the remaining liquid and start the process again!
Which teas to use?
- It is recommended to use organic tea whenever possible to avoid exposing the scoby to pesticides.
- Black tea is the most favourable for the scoby as it consists of fully fermentable leaves.
- *Please note: avoid black teas that contain oils such as Earl Grey tea, chai tea, flavoured Ceylon teas, etc. as they can become rancid during fermentation and are quite hard on the scoby.
- Green tea comes from the same plant as black tea but it is processed differently. Green tea is not fermented. While not as ideal as black tea for fermenting kombucha, green tea provides most of the necessary nutrients and can be used in combination with black or herbal teas. Green teas tend to brew a little faster than black tea, and yields a lighter colour, and more soft-tasting kombucha. Jasmine green tea makes a particularly tasty kombucha.
- You can also use herbal teas but they do not contain the necessary nutrients to nourish the scoby and it is more difficult to control the pH level. Therefore it is advisable to use it in combination with black tea (at least 25% black tea).
- *Please note: Beware of herbal teas containing oils i.e. peppermint, chamomile, ginger, etc. as per above.
Can I use decaffeinated teas?
- Decaffeinated tea can be used or a more effective method would be to strain off the caffeine first.
- To do this: Prepare a cup of hot water as well as fill your container with hot water for making kombucha. Allow your tea to steep in the cup of hot water for 30 to 60 seconds. Discard the cup of water. Then use the same tea bags to make the tea for your kombucha. Approximately 80% to 90% of the caffeine is released in that first minute of steeping.
Can I use different sugar alternatives?
- Unfortunately, sugar is required for the fermentation process and cannot be bypassed. Without it, it will not produce all the beneficial substances produced from breaking down the sugar.
- White cane sugar produces the most reliable results with kombucha, since it is the easiest for the scoby to digest and therefore produces the most consistent pH level.
- Organic evaporated cane crystals (OECC) is a good alternative to this as it contains no GMOs or pesticides, but it is slightly less digestible.
- Unrefined sugar or brown sugar, which contains molasses, can work, but it is not really recommended. This is so, because it is not only again more difficult to digest, but it is quite unpleasant tasting. You could boil the tea first if you really want to use it though, to help the digestibility of it.
- Honey, rice syrup, agave, maple syrup, coconut sugar, etc., are not ideal for kombucha production as they do not give a consistent pH level.
- *Please note: Raw honey also contains its own bacterial profile so may disrupt the balance of yeast and bacteria in the scoby.
- Artificial sweeteners (aspartame, etc.) or non-caloric sweeteners like stevia or xylitol cannot be utilized as food by the scoby and will be detrimental to the batch and harmful to the scoby, and will produce a beverage that is unsafe to consume.
Does it matter what water I use?
- Creating a safe batch of kombucha requires maintaining a proper level of acid from the start until the scoby begins to produce its own acids. Therefore, it is important which liquids we use.
- While tap water can be used, it is recommended to use filtered water free of as many contaminants as possible. Contaminants such as chlorine, chloramines, and fluoride can be detrimental to a batch of kombucha and the health of the scoby.
- Distilled water and reverse osmosis water can also be used to brew kombucha.
- Do not use alkaline water (processed through a water ionizer) to brew kombucha: it may kill the culture as it is not acidic enough.
What material for jars can be used?
- Glass, china, glazed earthenware or stainless steel containers can be used but glass is best.
- Avoid metal containers (other than stainless steel) as the acids formed may react with the metals.
- Also avoid containers made of polyvinylchloride (PVC) or polystyrene.
Which bottles are best for storing the Kombucha?
- Grolsch-style flip-top airtight bottles make the perfect containers for storing your finished kombucha tea.
- Dark colors (brown, green, and blue) are most effective in ensuring light doesn’t degrade the kombucha. Avoid clear bottles where possible.