Alkoholkilde

Alkoholkilde is a term used to describe raw materials or feedstocks from which alcohol, particularly ethanol, can be produced. In industrial contexts it denotes substances that contain fermentable sugars or hydrolyzable starches, which are converted into alcohol by microorganisms or chemical processes. The main categories are sugar-rich feedstocks, starch-based feedstocks, and lignocellulosic biomass.

Sugar-rich feedstocks include sucrose sources such as sugarcane and sugar beet, as well as glucose/fructose syrups and molasses. Starch-based feedstocks such as corn, wheat, and barley require pretreatment and enzymatic saccharification to release fermentable sugars before fermentation. Lignocellulosic biomass—wood residues, straw, and dedicated energy crops—needs pretreatment and enzymatic hydrolysis to release sugars from cellulose and hemicellulose. In some cases, microorganisms are engineered to ferment a broader range of sugars.

During fermentation, yeasts convert sugars into ethanol and carbon dioxide, after which ethanol is purified by distillation. While fermentation is the common route for beverage and fuel ethanol, a chemical route—hydration of ethylene—produces ethanol without biological feedstocks, though it is used in some industrial contexts.

Sustainability considerations include energy balance, greenhouse gas emissions, land use, and competition with food production. Developments aim to expand non-food feedstocks and improve conversion efficiency through pretreatment technologies and biotechnological approaches.