A method for fermenting carbohydrate-rich crops is provided. Sugar beet, sugar cane, sweet sorghum, tropical maize hybrids and fruits are rich in simple sugars; potato, sweet potato, cassava and yam are rich in starch; and Jerusalem artichoke is rich in inulin. This method uses vacuum infusion to infuse yeast into the intercellular space (apoplast) of the parenchyma tissue. The simple sugars diffuse into the apoplast, come into contact with the yeast and produce ethanol. Ethanol can be extracted from the crop by vacuum stripping or crushing or can be left inside the starchy crop to preserve it. In some variants, pectinase enzymes degrade the parenchyma cell walls to speed up diffusion of simple sugars to the yeast, speed up diffusion of amylase to starch granules or speed up diffusion of inulinase to insoluble inulin.
