Brewing Science: Gravity, ABV, Attenuation, Bitterness & Colour

What you'll build

What you will be able to do

Each lab ends with a concrete result that you build yourself and the checker confirms, cell by cell.

• Turn a grain bill into gravity points, predict the original gravity at your brewhouse efficiency, and work the efficiency back out from the measured gravity.
• Estimate the alcohol of six beers with the classic factor 131.25 and with a more accurate formula, and see where the two drift apart.
• Calculate how much of the sugar the yeast used, first as the apparent attenuation from the gravities, then as the real attenuation that corrects for the alcohol.
• Estimate the bitterness of a pale ale hop by hop: the gravity and boil-time factors, the utilisation, the alpha acids added and the IBU.
• Turn the grain bill into malt colour units, estimate the beer colour in SRM with the Morey equation, convert it to EBC and chart which malt gives the colour.
• Calculate how many mg/L of calcium, magnesium, sulfate and chloride three brewing salts add, the final water profile, its sulfate-to-chloride ratio and the gypsum needed for a target.
• Work out how many billion yeast cells five beers need from their gravity, volume and style, how many cells a pack still has, and how many packs to pitch.
• Estimate the CO₂ still dissolved in the beer at each temperature, the dextrose needed to reach the target carbonation, chart it and work out the sugar per bottle.