For Christmas this year, I received a Kombucha homebrewing kit. I had heard of kombucha in passing, but hadn’t ever actually tried it before. However, I have done homebrewed beer and sourdough in the past, so I am somewhat familiar with fermented treats. I had always been a bit afraid of trying the kombucha I have seen in stores but getting a chance to make it myself peaked my interest.

Trying kombucha for the first time

After unpacking the kit and reading through the instructions it was clear that I would need to have some idea of what flavors I want in my homebrewed product before I start. Most resources say to start tasting the product after about a week of fermentation and bottling when it gets the best balance of sour and sweet. Since I had no idea what kombucha tasted like when made correctly, this would be a difficult task.

I decided to pick up a few bottles of commercially produced kombucha so I could baseline my palate (as well as seeing if I even liked the stuff!). After a quick trip to the store, I had two bottles to try: GT’s Synergy Original and GT’s Synergy Cosmic Cranberry. I started with the cranberry. I wasn’t completely sold on the first sip, but wasn’t immediately repulsed either. After the first quarter of the bottle, I was a fan! The sour flavors reminded me of the sour beers I had started to experiment with at the end of my homebrewing streak (which makes sense, since sour beers usually use a lactic acid bacteria). I tried the Synergy Original the next day and liked it even more!

Now my refrigerator is full of different bottles to try. I decided to pickup a bunch of GT’s various flavors not only to see what I like, but also to build a stock of bottles for my homebrew once I start that.

Terminology (SCOBY vs Pellicle)

My motto is “If it’s worth doing, it’s worth overdoing”, so I have been doing a lot of research regarding kombucha in general and homebrewing. One thing that caught me off-guard is the general confusion on the internet regarding the SCOBY vs the pellicle when brewing. Many sites (mostly small-scale homebrew guides) call the jelly-like disk that grows on top of the tea during fermentation the “SCOBY” and indicate that it is absolutely vital to the brewing process. There are guides on how to grow a SCOBY, how to maintain it, how to store it. However, some additional reading regarding the actual microbial mechanics of kombucha fermentation show that this is not the correct terminology nor the as vital to the brew as indicated.

What do these terms actually mean?

Among more professional and informed brewers, it is widely accepted that not only is that jelly chunk not really the SCOBY, it also isn’t really necessary.

SCOBY

SCOBY stands for Symbiotic Colony of Bacteria and Yeast. It is the specific mix of yeasts and bacteria that ferment the tea to produce kombucha. When brewing (or consuming the end product), these bacteria and yeast live all throughout the liquid itself. All of the beneficial probiotics lauded in kombucha are the SCOBY.

Pellicle

The pellicle is what many less informed sites refer to as the SCOBY. This is the large chunk of goo that forms at the top of the fermented liquid. Some research indicates that it is made up mostly of a very pure form of cellulose (the same stuff most plants are made of). This cellulose mat is generated mostly by one specific bacteria in the SCOBY mix: Komagataeibacter xylinus. K. xylinus has the curious ability to produce this pure cellulose as a byproduct of its oxidation of sugars and ethanol to acetic acid (which helps keep the kombucha sour). This cellulose accumulates on the surface of the fermenting tea and forms a thick layer called the pellicle.

Terminology Conclusions

Currently, it seems that the homebrewer’s focus on maintaining the pellicle is misguided. The pellicle isn’t an vital part of making kombucha but more of a byproduct of the proper fermentation of the tea. When starting a new batch many homebrewing sites focus on moving the pellicle to the new vessel and casually mention also added some previously fermented tea. However, this focus should probably be flipped. The pellicle can probably be discarded. The previously fermented tea (the “starter liquid”) is the real star and serves to inoculate the new batch with the proper SCOBY.

First Batch Plans

I have some plans for how I will try my homebrewing but I am not ready to make my first batch yet. I am currently waiting on a heating pad (to keep the fermentation vessel at a comfortable temperature in my cold house) as well as needing to drink all that kombucha I bought so I will have enough bottles.

After my first batch using the materials provided from the kit, I intend to take two bottles worth of the 1F (1st fermentation) liquid and store them in the refrigerator as new starter liquid (as well as a backup in case of mold). Many homebrew sites have elaborate setups for “SCOBY hotels” to maintain a collection of pellicles. Given the information above, I don’t believe this is necessary. I think some refrigerated 1f will be a fine starter and will last a good while in the refrigerator. After all, many sites say to use commercial raw kombucha as a starter if you don’t have one. What is the difference between GT’s in the fridge and my own?

Time will tell if this is the right way to approach the brew or folly. It will be a fun adventure either way!