Great article! I worked on an organic farm which produced and bottled its own wine every year.
In order for the wine to not go bad during fermentation the grapes have to have on average 25% sugar content measured using a BRIX refractometer.
Once the grapes get the OK grapes were harvested by hand and thrown into a hand driven crushing machine where the pulp and juice would land in a massive vat.
Fermentation was controlled using temperature only.
drop a wide piece of hose with hot water running through it in a closed circuit into the vat to increase fermentation
Drop a massive sealed bucket of ice into vat to cool down fermentation.
The vat had to be checked on multiple times a day and hand manipulated to allow oxygen etc to permeate.