Fermented ethyl alcohol can be produced from all sorts of farm crops, either widely grown or with development potential. In the future, ligno-cellulose resources from farms and forests may contribute to the production of ethanol, once sugar processing techniques and fermentation have been fully developed and gained a competitive edge.
Three major industries are involved:
- Crops containing sucrose and fruit containing sugar that can be fermented directly: beet, sugar cane, grapes, apples etc.
- Crops rich in starch, which can be hydrolysed to produce glucose and fermentable sugar: cereal plants such as wheat and corn, Jerusalem artichokes, potatoes, manioc etc.
- Ligno-cellulose plants, the cellulose of which can be broken down into fermentable sugar: wood, coppice, plant waste, miscanthus and other high-energy crops, straw etc.
NB: Ethanol can also be synthesised industrially, as opposed to natural fermentation. The process involves adding water to ethylene derived from oil to obtain ethanol. Unlike agricultural alcohol, this is a fossil fuel.