By mounting a magnet and a hall-effect sensor or an opaque barrier and a photodiode + light on the moving portion and lid, respectively, of the vapor-lock used on top of this 5-gallon carboy of fermenting beer, it should be possible to measure the coefficient of total CO2 production by the yeast in the brew.
It's a simple - and course - idea. Magnet glued to the top of the "vapor lock". Carefully observe its motion. CO2 is produced as a product of yeast fermenting simple sugars in the beer "mash". As they do so, they produce CO2. The CO2 escapes through the Vapor Lock. As it does so, part of the Vapor Lock assembly floats up, then down, in water. A magnet on this floating portion of the vapor lock and a hall-effect sensor above it should detect pulses of the metabolic activity.
macowell 1 year ago