Thursday, July 10, 2014
Passing Gas: Passive CO2 Blowout Tube System
I’ve got gas—CO2 gas that is! One problem all we fermenters are familiar with is CO2 build up and spontaneous explosions—it just happens. Here’s a little trick that I learned from my friends at the Victory Brewing Company using a modified beer brewer’s blowout system; it works for both first and second fermentation. This resolves a problem with unpredictable gas emission and explosions from an over productive batch of kimchee. As fermented foods produce CO2 in a vessel, gases build and displaces air and oxygen; along with brine this creates an anaerobic environment that lactic acid bacteria (LAB) need to colonize. The blowout tube used for beer brewing efficiently drains gases... instead of overflowing beer mash, as is its intended use. Excess gases lead through a hose from the fermentation vessel into a bottle of water which then absorbs CO2 and sulfide compounds. It also absorbs most of the aroma as sulfide molecules are rendered into a weak acid. The result from this experiment is a more flavorful, balanced kimchee with a less aggressive aroma. And the bottled water... anyone up for some kimchee soda?