While it's easy to brew kombucha in pretty much any container, it's an important decision to choose the best vessel you can find. Choosing a brewing vessel can make a huge difference in the quality, and of course quantity, of your kombucha brew. So, in an effort to clarify a few things for brewers new or seasoned, read below to find out more about these essential instruments.
In choosing your brewing vessel, look for a few key characteristics:
- The vessel should be glass, ceramic, stainless steel (304 or brewer grade, not cooking grade) or wood. While many will say that food-grade plastic can be used, undesirable flavors often result from continued use of plastic. Glass is an inert material and will not allow the leaching of chemicals into your brew. If brewing in a ceramic vessel, be sure it is lead-free (the crocks that KBBK carries are lead-free and USA-made). Stainless steel is especially popular in commercial brewing environments and as such will work for home brewing as well. Some choose to brew in wooden barrels, which is also fine, and will contribute woody characteristics to your brew.
- The vessel should be wide-mouthed. The kombucha SCOBY requires that air be constantly exchanged with the outside environment, as it is constantly taking in oxygen and expelling CO2. A wide surface area ensures fast growth, as well as quick acidification of the tea. This results in a healthy culture. The wider the area for the culture to exchange gases, the more numerous are the antibacterial byproducts of SCOBY metabolism. Keep in mind that although your SCOBY will grow in tall, narrow-mouthed vessels, it will do so less vigorously.
- The size of the vessel is important, though not quite so much as the available surface area. Similar to the surface area, however, the more shallow the depth of liquid in the fermentation vessel, the faster the SCOBY grows and processes the tea into delicious kombucha.
- The shape of the vessel is a matter of personal preference, and the culture will take the shape of the container at the level of the liquid’s surface.
- Vessels with a spigot can be intermittently convenient but can also tend to cause headaches. While it may seem useful to use the spigot and not worry about using or cleaning an auto-siphon, or requiring precise pouring technique, brewers will find the spigot becoming periodically clogged with kombucha culture; you'll find yourself not using the spigot as frequently as you are using it.
- Additionally, the materials from which the vessel's spigot is made could be contributing chemicals to your brew through leaching. As kombucha is very acidic, any substance that is reactive to such liquids can potentially release toxins into your brew (something interesting to consider when kombucha is a detoxifying drink). It's for precisely this reason that we advise against brewing in plastic, even BPA-free or food-grade plastic vessels.
- An auto-siphon can be just as simple to use to extract kombucha, resists transfer of large chunks of culture, is easy to clean, and requires no relocation of the brewing vessel.
Ventilation is very important for your brewing vessel. Without proper ventilation, your brew's bacteria will be unable to access the oxygen they need to produce a nicely acidic kombucha. So, consider using fans in bigger brewing setups as well as completely porous (but not too porous) covers for your brewing vessel! Remember that cheese cloth is too porous and can allow fruit flies entry into your brew.
Remember that it's not only kombucha that you can ferment in your vessels - pretty much any vegetable ferment (kimchi, sauerkraut) and some liquid ferments will work too - think kefir, mead, kvass etc. So, open up your horizons and start scouring flea markets, pawn shops, garage sales and antique malls for some sweet fermentation vessels!