The key to optimizing alcohol production from cereals is a full understanding of the physiology and processing characteristics of different cereals. This study examined the maximum alcohol yields that can be obtained from wheat and maize using different processing technologies. Lower processing temperatures (85°C) resulted in high alcohol yields from wheat (a temperate crop), whereas higher processing temperatures (142°C) gave maximum alcohol yields from maize (a tropical crop). Similar trends were also observed when the spent grains from these cereals were processed using commercial enzymes. Mill settings were additional factors in influencing alcohol production. Wheat has the potential to produce higher alcohol yields when compared with maize, when residual biomass (i.e. spent grains) saccharification using selected commercial enzymes is taken into account. While this approach is not applicable for the Scotch whisky industry owing to strict legislation forbidding the use of exogenous enzymes, this is pertinent for bioethanol production to increase the alcohol yield obtained from both starch and lignocellulosic components of whole cereal grains. Wheat and maize processing temperatures and the use of processing aids are of potential economic benefit to bioethanol producers and to beverage alcohol producers seeking to understand the factors influencing the processing properties of different cereals.