Which of the following is not a method of ethanol production?

Sublimation is not a method of ethanol production. Let's break this down.

Ethanol, also known as ethyl alcohol, is primarily produced through processes that involve the fermentation of sugars, which is the method where yeast converts sugar into alcohol and carbon dioxide. Brewing is a specific type of fermentation focused on producing beer, where grains are used to provide the necessary sugars. Distillation is often employed after fermentation to purify and concentrate the ethanol, enhancing its potency.

On the other hand, sublimation refers to a phase transition where a substance moves directly from a solid to a gas without passing through a liquid state. This process does not apply to ethanol production and does not involve the conversion of sugars into alcohol. Thus, sublimation does not have any relevance in the context of producing ethanol, making it the correct choice among the options provided.