Spirits - Distillation Flashcards
What is a retort/Thumper?
A second (or third) chamber attached to a pot still that allows you to run another distillation without the taxing process of emptying and refilling the original pot.
Retorts are primarily seen in Rum production (Jamaican distilleries, Mount Gay & Foursquare in Barbados, DDL in Guyana.
Called a thumper in bourbon production.
What is the standard input & output ABV for pot still distillation?
Almost all distillates start as a beer or wine between 8-10% ABV, coming out at a maximum ABV of 45%.
What is the goal of distillation?
‘Resolution’ - the separation of compounds by taking advantage of their different boiling points.
What is reflux?
Reflux is the tendency for vapors to recondense before reaching the condenser at the top of the still (usually because they’ve transferred heat to to the still itself).
More reflux in a still = higher potential ABV in spirit, lighter in flavor.
What is the biggest factor that dictates reflux?
The shape/height of the still. Short still = Less Reflux. Smaller Neck = Less Reflux.
Constrictions/Bulges in still - More Reflux
Why does high reflux make for a lighter tasting spirit?
Reflux simply allows the vapors more time in contact with the copper. Copper has the ability to ‘pull’ heavy tasting congeners/compounds out of the vapor. More pulling, more time for lighter compounds to escape.
What is a congener?
Anything produced by yeast that isn’t ethanol.
Esters, Acids, Higher Alcohols, etc.
Does a cask lose more water or alcohol in the angel’s share?
Depends on a few different conditions. Barrels in humid climates lose more alcohol than water (Scotland etc), in Dry climates they lose more water than alcohol (Kentucky).
Wood grain size also makes a difference, as water molecules are smaller than alcohol molecules.
What is the class of compounds credited with the ‘deeper, darker’ flavors of aged spirits, like tobacco, leather, spice etc?
Phenol Aldehydes, (almost) all of which are formed during the aging process. Biggest notable exception are the smoky notes introduced by peat.
How does gas chromatography work?
You add Ions (electrical charge) to a substance then use a magnetic field to effectively split compounds apart based on their mass-to-electrical-charge ratios, effectively splitting all the compounds of a solution into different streams, reading from most volatile to least volatile.
Feather & Bowling Ball with wind analogy.
Why do spirits taste different than they smell?
When you smell a spirit, you’re getting all of those aromatics in a single stream. When you taste one, the heat from you palate will shake loose molecules in order of their volatility (attack, mid palate, finish).
So you could, in theory, look at a gas chromatography read out and predict the order in which you taste things.
