On food and cooking the science and lore of the kitchen ( PDFDrive ) 1432

condense and are collected as a separate liquid The concentrated alcoholic liquid is then modified in various ways for consumption It may be flavored with herbs or spices, or aged in wood barrels The alcohol content is usually adjusted with the addition of water before it’s bottled for sale The Distilling Process The essential principle of distillation is a simple one: both alcohol and aromatic substances are more volatile in water than water itself, so they evaporate in disproportionate amounts from wine and beer and become concentrated in the vapor But it’s not a simple matter to make a delicious distilled alcohol, or even a drinkable one Yeast fermentation produces thousands of volatile substances, and not all of them are desirable Some are unpleasant, and others, notably methanol, are dangerously toxic Selecting Desirable Volatiles Distillers must therefore control the composition of the distilled liquid They this by subdividing the vapor into fractions that are more and less volatile, and collecting mainly the fraction that is richest in alcohol The fraction more volatile than alcohol, often called the “heads” or “foreshots” because it evaporates earlier than alcohol, includes toxic methanol, or wood alcohol, and acetone The fraction that’s less volatile than alcohol, the “tails” or “feints,” includes a host of aromatic substances that are desirable Among these “congeners” (substances that accompany alcohol) are esters, terpenes, and volatile phenolics, along with some substances that are desirable in limited amounts The most notable of the latter are the “higher” alcohols, whose long, fat-like chains can give spirits a full, almost oily body, but also contribute a pronounced harsh flavor and unpleasant aftereffects They’re often called fusel oils  ... Distillers must therefore control the composition of the distilled liquid They this by subdividing the vapor into fractions that are more and less volatile, and collecting mainly the fraction that is... alcohol The fraction more volatile than alcohol, often called the “heads” or “foreshots” because it evaporates earlier than alcohol, includes toxic methanol, or wood alcohol, and acetone The fraction that’s... than alcohol, the “tails” or “feints,” includes a host of aromatic substances that are desirable Among these “congeners” (substances that accompany alcohol) are esters, terpenes, and volatile