Fermentation Growth-Rate Phase Plane

Anaerobic fermentation is not a simple race to convert all the sugar in the tank — the yeast doing the converting is slowly poisoning itself with its own product. Instead of watching a rendered fermenter, this view puts the batch on its growth-rate phase plane: sugar concentration on one axis, ethanol concentration on the other, and a live heatmap of the Monod-Levenspiel growth rate μ(S,P) painted across the whole plane. The bright trail is the batch's actual (S,P) path — you watch the same numbers used by the 3D tank sweep across a static map of where growth is fast and where it collapses. Tune the initial sugar load, fermentation temperature, the strain's ethanol tolerance and how sharply inhibition kicks in, and read off the final ethanol yield as a percentage of the Gay-Lussac theoretical maximum — the same trade-off fuel-ethanol plants balance when choosing feedstock loading and yeast strains.