SCOBY? EW TELL ME MORE.
Updated: Apr 22, 2020
All great booch starts with the same ingredient. A SCOBY.
So what is a SCOBY? It stands for symbiotic culture of bacteria and yeasts. It is essentially a wee hoose for bacteria and yeasts to thrive. Without a SCOBY you can't make kombucha. I will introduce you to Betty, she's my SCOBY (I'm going to refer to the SCOBY as Betty from now on). She's a lil ugly but what an angel she is.
If we take a look at Betty you can see she is kinda pale, kinda gooey. She's bloody radiant. The darker patch is caused by CO2 building up within the liquid under her and trying to escape. This CO2 sometimes escapes unevenly out the sides, sometimes it pushes parts of Betty out the liquid and sometimes it just bursts holes right through her. It doesn't affect her ability to make booch however. Betty has four other sisters who all ferment differently. Betty white ferments a green/white tea blend. She is much lighter than this one here due to not being as stained by the sweet tea. Betty coffee on the other hand is pretty dark due to being coloured by the coffee.
If we look underneath Betty we can see the layers that she is made up with. Each time a new batch of kombucha is made a new layer forms. Why? As the bacteria in Betty multiply they excrete cellulose. This floats on the top of the liquid and grows as the sweet tea ferments. You can see the formation of the mat on the lighter areas that are on Betty. Eventually the mat will cover the surface of Betty and will thicken up as more cellulose is excreted by the bacteria. This is one of Betty's bairns. As long as Betty lives and is continuously fed she will continue to have bairns. Newer layers are lighter as they haven't yet been submerged in the liquid and stained by the tea.
If you look closely you can see the variation in colour and shape between each layer. Some grow flat whilst other grow lumpy and bumpy. The layer at the bottom is much darker than the top one. The type of tea you use affects the colour. This is a blend of black and green so Betty and her bairns often end up an amber colour. Black tea makes them much darker and coffee makes them near enough black. The bumps are caused by me peeling away the layers over time. Newer layers ferment kombucha quicker so its important to give Betty a wee haircut from time to time. Treat yo self hunneh.
Flip Betty on to her other side and here we can see some of the yeasts that are involved in the booch making process. The darker stringy bits float around quite freely in the liquid, whereas the lighter foamy looking bits have been trapped within the layers. Yeasts are often confused with mould. Mould will only form on the surface of the liquid and will slip off if you move the vessel at an angle. We need both the yeast and the bacteria as they work in harmony to create the kombucha. The yeast works to ferment the sugar into alcohol and then the bacteria transform this into acetic acid. The cute little cloths used to cover the kombucha vessel are there to allow the kombucha to ferment aerobically, the bacteria has to come into contact with oxygen to convert the alcohol into acid. However, flies LOVE fermenting things (mmmm tasty ferments), so the cloth keeps those little mites out. Pro tip if the top of your SCOBY starts wiggling, chuck it and start again. The bacteria works quickly utilising the alcohol and turning it into acid meaning that kombucha contains trace amount of alcohol. Typically there is more alcohol in your toothpaste than kombucha.
Heres one of Betty's bairns. In my hand I have a SCOBY from a 3 Litre jar (just to put some perspective on how monstrous Betty is). A SCOBY isn't going to come in and take over your house. They will only grow to the size of container you put them in. I grew Betty in stages using the size of SCOBY I have in my hand. I transferred it from vessel to vessel until I had managed to grow the Betty you see right here. I spoke about mould earlier on. When you make kombucha and handle your own Betty its really important to make sure that you aren't transferring any bacteria from the environment into the brew. Cleanliness is key to healthy brews. Never touch the SCOBY with your bare hands or you risk contaminating it. Make sure your equipment is cleaned and sanitised and always make sure you are using enough starter liquid to drop the PH of your kombucha down straight away so that when the fermentation process starts you won't be creating a non acidic environment. Harmful bacteria, strains of wild yeasts and mould can all grow down to a PH of 4.2, you want to make sure that your starter liquid is way below this to bring the PH down straight away to not allow these pathogens to harm you or your booch.
Not all SCOBYs are instagrammable. They vary in shape, size, colour, depth. In all my time brewing I have found that the best kombucha is made by the ugliest of SCOBYs. Those that look gnarly and hard done by seem to work harder. Their semi insulting looks don't last long due to the constant excretion of cellulose on the surface of them. This lil baby in my hand isnt as perfect as the one above, you can see where she hasn't wanted to give up her layers on haircutting day (some of them are TOUGH to get through). However she has brewed 3 Litres of white peony perfectly and given a couple weeks of uninterrupted brewing she would be "perfect".
Much like a sourdough starter you quickly become attached to your SCOBY and find yourself thinking about it all the time and wondering what to do with it when you go on holiday, can you trust your parents to babysit?? You squeal when you see your first ever layer being made and sit and chat away to it sometimes. Betty is the cutest fermenter and a super useful kitchen pet. Danke Betty, we love u!!! Give it a go today! Buy your own SCOBY n name it whatever the hell you like. Pick out cute jars and cloths for it n coordinate its rubber bands. Find out what tea she likes and even make one for you and one for her! Have fun n booch on.