Fizzy Funky Fresh : Kombucha 101
I first tried Kombucha roughly 4 or 5 years ago, and although I admittedly didn’t really understand what it even was, I was immediately into it. It was the fizziness, the intense flavors, the acidic tang that sprung me awake, the bright and refreshing aromas, and not to mention the funk. That essence of fermentation that brings unexpected flavors and aromas together.
As I became more interested in Kombucha, I also became more interested in fermentation and fermented products. I quickly discovered the huge global community that has historically used fermentation both as a means to create traditional cultural foods and as a means to survival (the two are often intertwined), as well as the rising global community that is returning to these traditions. This is only to say that I soon realized that this product I was so mystified by, was being produced all across the world in people’s home kitchens, so, naturally, I had to try it myself.
First of all, I’m a sucker for any involved cooking project. New processes, new tools, I’m all in. Second of all, Kombucha is a fairly expensive non-alcoholic beverage at most stores. So, the idea that I could start my own brewing set-up that would pay for itself in only a batch or two, and then provide me with incredibly cheap (and more flavorful) Kombucha from there on out, made it a done deal.
Before we get too far into my adventure with Kombucha, we should probably talk about what it is.
What is it?
In its most simple form, Kombucha is essentially just fermented sweet tea. Fruit juices, as well as herbs and vegetables and spices, are added to produce the limitless flavor profiles of this fizzy drink, as well as to fuel secondary fermentation (well get into that later). But, at its core, it’s just fermented sweet tea.
How is it made?
We have a recipe for a master-brew (essentially a template from which you can experiment and develop your own specialized recipe) here! However, for the sake of a brief explanation, the very basic process is as follows:
A large batch of sweet tea is brewed
That sweet tea is cooled, and then added to a vessel with a Scoby, which is then covered and left to ferment (the Scoby consumes the sugar from the tea, creating alcohol and then acetic acid in a continuous process)
At a time chosen by the brewer, this now partially-fermented tea is transferred to sealed bottles with your desired flavorings
In this sealed container, residual bacteria and yeast continue to consume the sugars in the flavored tea, however, now with nowhere for the carbon dioxide that is produced to escape, it begins to carbonate the beverage
The secondary fermentation vessels are then chilled, which slows the fermentation process and locks the carbon dioxide in the tea, and the Kombucha is ready to be consumed!
Ok, you might be asking yourself “what is a Scoby?”, “what actually is fermentation?”, “what’s the difference between primary and secondary fermentation?”, “how am I supposed to know when it’s ready?”, “what flavorings should I use?”. If you are asking yourself any of these questions, first of all, I’d like to give you a warm welcome to the Fermentation-Nerds club, we’re so happy to have you :) . Second of all, you’re not alone! These are all perfectly valid questions for someone just entering the realm of fermentation and kombucha-making! I’ll try to demystify this as much as I can for you:
A mature Scoby, look at the layers!
“What is a Scoby?”
“Scoby” is actually an acronym for “Symbiotic Culture of Bacteria and Yeast”. A Scoby is essentially a mass of bacteria that almost acts like a single organism, feeding on sugars and growing as whole. That might skeeve you out a bit, but it shouldn't! It’s totally safe, technically edible by itself, and admittedly quite a weird thing to handle and look at at first. This semi-gelatinous, semi-leathery bacterial mass is the engine behind kombucha! It grows in layers that die over time, is sensitive to changes in its home-liquid (like sugar content, impurities, and temperature), and will quickly become like a pet you care deeply for and check on regularly….I know. It grows to the edges of the container you put it in, and then grows in thickness, creating those visible sheets I mentioned earlier. Within the Scoby, the yeast converts sugar into alcohol, and the bacteria converts the alcohol into acetic acid. It’s worth mentioning that the Scoby will carry flavors through its life, so if you’re flavoring the primary vessel with wildly different types of teas, you may want several different Scobys!
“What is fermentation?”
A quick definition is “fermentation is the transformation of food by microorganisms”.This process can, from a flavor standpoint, introduce a whole host of flavors that can be lost in some foods in their natural forms. These flavors can be sour, umami, sweetness, and overall funky complexity, and this is largely due to breaking down large molecular chains into smaller constituents that our bodies can process. I’m sure many of you have heard that fermented products have health benefits. This is because these products introduce good bacteria into your digestive system, that can aid in digestion, and can, in many senses, pre-digest some of the food for you.
“What’s the difference between primary and secondary fermentation?”
Primary fermentation happens in the vessel that houses your Scoby. Since this tea will make up most if not all of your final product, this is where the majority of the fermentation happens. In this process, ample air exposure and large amounts of sugar allows fermentation to happen rapidly. Secondary fermentation happens in sealed bottles. At this stage, you may introduce new sugars into the tea, which will give the bacteria and yeast within the tea a source of food to continue fermentation. Because the bottle is sealed, fermentation will happen more slowly, but the carbon dioxide created during the fermentation process will be sealed within the bottle and will actively “carbonate” the beverage.
“How am I supposed to know when it’s ready?”
You want to pull the kombucha from primary fermentation once there is a balance of certain flavors. You want neither sweetness nor sourness and acidity to overpower. It should be somewhere in between. While preference reigns as the most important factor, if you haven’t had a lot of kombucha before, it can be helpful to try a few commercial products to try and get a feel for what the range of “balanced” can taste like!
Like I said before, this is ultimately up to you. There are reasonable bounds of course (if you don’t wait long enough, you’ll essentially just have sweet tea, and if you wait far too long you may have something closer to vinegar), but you should dial the kombucha to your own palette! Like it sweeter? Pull it sooner! Like it more acidic and funky? Let it ferment longer!
For secondary fermentation, it can be very difficult to judge when it’s ready, so you really just have to test! When I make batches, I make 6 bottles at a time. After day 4, I will begin testing. I will pop 1 of the 6 in the fridge and try it once it’s cooled. Not fizzy at all? The rest of the bottles should be left to ferment for at least another 2 days. Fizzy but not quite enough? Let them all sit another day and then transfer! Perfect? Refrigerate them all!
“What flavorings should I use?”
Oh boy, the world = your oyster. Black tea and fruit juices are the most common, but by no means are the only allowed flavorings. Many restaurants and companies use all kinds of teas and fruits and vegetable juices. If you want to confine the flavoring to the second part of the process, we recommend doing so with infusions and juices! This can be fruit juices (or even vegetable juices) by themselves, mixed into blends, and/or infused with other flavors like ginger (or other flavorful root vegetables), spices, herbs, etc. You can also change the flavoring at the beginning by using different kinds of teas. Keep in mind, the Scoby itself takes on the tea flavor, so if you plan on using different teas for different batches, you may want to create a small “library of Scobys” (this library would be Scobys that are used for different kinds of tea, “this is my black tea Scoby, and this is my chamomile Scoby” etc)
Now that you have a basic understanding of what Kombucha is and how it’s made, check out our Master Brew Recipe and try it out for yourself!