SCOBY Health

(Symbiotic Colony of Bacteria & Yeast)

 

Originally a blog post, I decided to make a page dedicated to the importance of maintaining a healthy SCOBY for quick reference. We'll update the page as needed. 

One of the keys to a successful brew lies in how healthy your SCOBY (Symbiotic Colony of Bacteria & Yeast) is. This is vital to komucha. Try to get a healthy SCOBY from a person- not a dehydrated or one that is shipped. If you don't know anyone, Kombucha Brooklyn is an excellent resource and a reference for many kombucha questions. Oftentimes new growth looks like mold and they provide photographic examples of what mold is versus SCOBY growth. Kombucha Kamp also has some basic but solid info on signs of a healthy SCOBY. 

Think about your SCOBY like this: it's a growing amalgamation of bacteria and yeast. Both of those things thrive in nasty places in your daily life but set that aside and consider the physical properties of those environments:

warm 

damp/humid/moist

restricted airflow 

Ideal temperatures are 72-85°F: too high will kill it, too low will result in lower CO2 gas levels. Depending on airflow and humidity levels, covering your SCOBY could range from a thin t-shirt to a thick towel or blanket.

In another life when my kombucha was at work with me, the greenhouse monster fans exchanged far too much air and heavily slowed SCOBY growth. Batches did better with a thick terry cloth towel doubled over to maintain some moisture. Currently, the kitchen in my house where my kombucha is now has very little airflow this time of year with all the windows closed so it grows better with a thin flour sack towel and a Mexican blanket on top to keep heat in, but summer is different with higher humidity levels. The heat in the house is set to 65°F and I brew in the kitchen with huge glass double doors (that unfortunately quickly cool the room). My four jars of kombucha sit on a terry towel on a glass end table that is placed directly over the kitchen's heat vent. The jars are then wrapped in Christmas lights and have a blanket on top. It's cold and dry here in New York. 

I would highly recommend invest in a small kitchen thermometer to temp check the brew and while brewing the tea as tea should be brewed at varying temperatures. Thermometers are invaluable and rocked my brewing world. Problems with effervescence dissipated when I realized I was brewing the tea leaves too long and the tea with the SCOBY was too cold. Plus is just makes you feel like a good scientist checking on your experiments.

This all said, there is no formula that works for everyone. A SCOBY is relatively forgiving as far as all of these variables. SCOBY size does seem to impact fermentation- they prefer wide mouth containers and larger, more mature SCOBY ferment tea quicker. My tea is usually ready for a second fermentation after 7-9 days and the second fermentation after 3-5 days, depending on the amount of fruit added and if the pressure is becoming too much for the bottle to bear. I'm still working on keeping bottles from shattering under pressure. The first few days are fine but they've been hitting a point where I've had to strain the fruit out before I really want to just so the bottles don't continue to ferment at an exponential rate and explode. If anyone has experience with this feel free to leave a comment. 

*This SCOBY has been split numerous times. The light pink top layer has formed in the last couple of weeks since I added Christmas lights which have expedited SCOBY growth. If I had the original SCOBY I received in October 2014, it would likely fill the 2 gallon jar. 

(written by Jesse, updated 1 February 2016)