Before we move into Spring here in the UK, we need to get through February, our coldest month. It’s peak flu season, and each year, just before Spring, I seem to catch some sort of cold. This year, I want to avoid getting sick, so I’ve been taking extra care to support my immune system. The first way I’ve been doing this is by adding home-made kimchi to my daily diet – this was the subject of Part One of this Gut Health Series, which you can find here.
Image of kimchi by Portuguese Gravity.
The second way I've been supporting my immune system is by drinking kombucha daily. In this Part Two, I’m going to share with you my super easy and utterly delicious recipe for kombucha.*
Image by Tim-Oliver Metz
While kombucha has been used as a health tonic across many cultures for thousands of years, it’s only relatively recently that Western science has started testing the traditional health claims. I’ve only read a small percentage of the hundreds of published scientific studies, so I can’t claim to be an expert. However, I would say that based on my reading, it’s fair to say the initial evidence looks promising, and kombucha is worthy of much more research. If you’re interested in reading the research, you can find it here.
As with much in life, the decision to include kombucha in your daily diet will have to be based on imperfect and incomplete information. For me, given that it’s been treated as a “Tea of Immortality” in China for the last 2000 years, and the initial research looks good, I’ve made the decision to include kombucha into my daily diet. **
Image by hyeongju seo
Once you get over the initial mental block and start-up admin, making your own kombucha is incredibly easy, cost effective and far more delicious than anything you can buy commercially.
Image by Shannon Nickerson
I’ve been brewing kombucha continuously for 6 months. I’ve made all the mistakes, so you don’t have to. I’ve written this post so that you can get started straight away. But if you’re planning to regularly brew kombucha, you will need to do further reading. For that, I recommend The Big Book of Kombucha by Hannah Crum and Alex LaGory. This book is a great resource, especially for trouble shooting and has wonderful ideas and recipes.
I hope this post and my recipe encourages you to have a go at brewing kombucha at home – that way you and your loved ones will have a continuous supply of this beautiful, nourishing tonic.
What is Kombucha?
Kombucha is sweet tea, fermented by the action of a symbiotic culture of bacteria and yeast – known as SCOBY.
Placing the SCOBY into the sweet tea solution
The SCOBY is a mat of cellulose nanofibers, in which both yeast and bacteria (usually Komagataeibacter xylinus) live symbiotically – each feed off the other’s fermentation by-product. In addition to the fermentation, the SCOBY has a mechanical use – it covers the top of the fermenting tea to reduce evaporation, protect against pathogens and seal in natural carbonation.
SCOBYs are an extraordinary living amalgam - they are being studied for a wide array of novel uses - everything from living bandages, water treatment, SCOBY cling film, and even the creation of a new type of polymer for use in electronics.
After a lot of experimentation and mistakes, I’ve developed an easy recipe that makes the best kombucha I’ve ever tasted. My recipe uses the continuous brew method – which I’ve found is the easier for the time poor. As the name states, the continuous brew method means that you are brewing kombucha continuously in the same vessel. The first brew takes anything from 10-15 days, and subsequent brews can take anything from 2-5 days.
This is the only glass vessel I could find that has a 10 litre capacity.
The idea is that from a 10 litre brewing vessel, you’ll take not more than 5 litres for drinking, and then top the vessel up with 5 litres of sweet tea, for further fermentation. You maybe able to do this continuously for up to a year before you need to completely empty the vessel and wash everything thoroughly.***
Image by Sigmund
The main barrier to making your own kombucha is getting together all the things you need to start brewing. After you’ve done this initial admin, everything becomes easy. After a lot of mistakes, I’ve settled on my brewing kit – which provides me with a continuous supply of utterly delicious kombucha, as well as providing me enough to give to any friend that may need a boost. Here’s my list.
10 litre, glass vessel
Plastic or silicone ladle
Large muslins and rubber bands
Glass bottles with non-metal lids to store your kombucha
Large stock pot
Colander with flat bottom
Loose leaf tea. I use Waitrose own label Earl Grey loose leaf tea.
SCOBY, appropriate for a 10 litre jar. You can get these online or from a kombucha brewing friend.
Starter liquid. You’ll need some kombucha to start off the brewing process. Commercial kombucha is fine.
I use this tea for my kombucha
First Brew – Method and Measurements
8.5 litres of Evian Water
760 grams of Rapadura Sugar
190 grams of loose leaf tea.****
1 litre of kombucha as a starter liquid.
Pour 3 litres of Evian water into a large stock pot and bring to boil. Before the water boils, pour in the sugar, stir and dissolve. Once the water boils, take off the heat and add the loose leaf tea. The easiest way to do this is to add the tea to a large colander that sits in the boiling water. This means that once the tea has brewed, it can be lifted out easily and no further straining needs to take place.
Using a colander to brew the sweet tea.
Brew the tea for 5 minutes and remove the tea leaves by lifting out the strainer. Leave to cool to room temperature and then add the rest of the water – 5.5 litres. Add this solution to the glass jar, top up with the starter liquid (kombucha) and mix with a non-mental implement. Gently place your SCOBY in the vessel – it should eventually float to the top.
Fold the muslin into quarters - so that there's four layers of muslin and secure it to the top of the vessel with a rubber band. That’s it. Depending on the temperature of your room, this sweet tea solution will take between 10-15 days to turn into kombucha. During the fermentation process, the yeast and bacteria in the SCOBY will eat the sugar and convert it into organic acids, carbon dioxide, and other by products.
Image by Jennifer Pallian
The longer the fermentation, the more the sugar is consumed by the microorganisms. The finished product should not taste particularly sweet. Do a taste test on day 10. If sugar is the first flavour profile you taste, then allow the brew to continue for a bit longer. After 10 days, taste test regularly. Once you are happy with the flavour balance, you can draw not more than 5 litres of the kombucha from the top of the vessel using your non-metal ladle by pressing down gently on the SCOBY with your ladle to fill it, and then fill your glass bottles. Keep your glass bottles in the fridge.
Image by Harrison Kugler
Subsequent Brews – Method and Measurements
Evian water – however much you plan to top up your continuous brew
80 grams of Rapadura sugar per litre of water
20 grams of loose leaf tea per litre of water****
Once you’ve drawn kombucha from your vessel, you’ll need to replenish your vessel by the amount you’ve drawn off. So if you’ve taken 5 litres of kombucha, you’ll need to make 5 litres of sweet tea solution to top up your vessel. Once you’ve made the amount of sweet tea solution (as per the instructions for your first brew), leave it to cool to room temperature. Once the sweet tea solution is at room temperature, add it to the glass vessel and secure the muslin to the top, as per the first brew. And that’s it. Subsequent batches will ferment much more quickly, so you can start taste testing after 2-3 days.
Feature image by hyeongju seo.
*The term "kombucha" is of Japanese origin. It is derived from the Japanese words "kō" (紅), which means "red," and "cha" (茶), which means "tea." However, the drink itself, as well as its fermentation process, is believed to have originated in China or Sri Lanka. The Japanese term "kombucha" was later adopted to refer to this fermented tea, and it eventually became the common name used worldwide.
**While kombucha is generally considered safe and nutritious, there are some individuals who should exercise caution or avoid kombucha completely. The following groups are just some examples of the types of people who should get medical advice before they drink kombucha, including people who:
· have histamine sensitivity, salt sensitivity, caffeine sensitivity or high blood pressure;
· are watching their sugar intake - depending on the length of fermentation, kombucha can contain differing amounts of sugar;
· have gastrointestinal issues, such as IBS or IBD;
· are sensitive to alcohol - any serving of kombucha may have a micro dose of alcohol, so anybody wanting to completely avoid alcohol should avoid kombucha;
· are pregnant or are breast feeding;
· are very young;
· are taking medication that may interact with fermented food; or
· have extremely compromised immune systems.
*** Maintaining impeccable cleanliness when making and storing kombucha is paramount to its safety, flavour, and longevity. Any unwanted contaminants can disrupt the fermentation process. Scrupulously cleaning utensils, containers, and hands helps prevent harmful bacteria from compromising the fermentation, ensuring a safe and delicious end product. If in doubt, err on the side of caution. The Big Book of Kombucha provides detailed information on safety and trouble shooting.
**** The amount of tea needed to succesfully brew kombucha will depend on a number of factors including the type of water you use as well as the quality and type of tea. My measurements are just a guide based on Evian water and the type of tea I use. As a rule of thumb, your sweet tea solution should taste like a strong cup of tea. If in doubt, brew stronger rather than weaker tea.