Cruzan begins fermentation in propagating tanks where a mix of 10:1 water and molasses are slowly introduced to the yeast which will begin the conversion to alcohol. After propagation the mixture is sent to one of the 13 main fermentation tanks. These hold considerably more liquid than the previous tanks and the mix is further diluted to 75% water and 25% molasses.
It is important at this point to regulate the temperature of the fermenting liquid. If it is allowed to reach too high of a temperature the yeast will die and fermentation will stop. So, for the 48 hours while fermentation is taking place the tanks are kept at a steady 90-92 degrees – an arduous task considering the fermentation process itself creates its own heat and in this case it is being done in tropical temperatures.