While there is no doubt ‘the phenomenon whereby Saccharomyces cerevisiae produces ethanol in aerobic conditions at high external glucose concentrations rather than producing biomass via the tricarboxylic acid (TCA) cycle’ (aka the Crabtree effect) is a thing, outside a lab equipped with a chemostat it cannot be easily observed by the avg homebrewer.
What is easily observed by the avg homebrewer is a rise in krausen, airlock activity, a slight temp increase, and a drop in gravity. These signs of activity take time. That time is routinely termed “lag” even though there may be no “lag phase” in Saccharomyces cerevisiae life cycle.
Brewing Scientists…