ferment

a state of agitation or turbulent change or development; "the political ferment produced new leadership"; "social unrest"

a substance capable of bringing about fermentation

a process in which an agent causes an organic substance to break down into simpler substances; especially, the anaerobic breakdown of sugar into alcohol

be in an agitated or excited state; "The Middle East is fermenting"; "Her mind ferments"

work up into agitation or excitement; "Islam is fermenting Africa"

cause to undergo fermentation; "We ferment the grapes for a very long time to achieve high alcohol content"; "The vintner worked the wine in big oak vats"

go sour or spoil; "The milk has soured"; "The wine worked"; "The cream has turned--we have to throw it out"