Distillation

Question 1

The distillation relies on a simple premise. Which one?

Answer 1

Alcohol has a lower boiling point than water.

Question 2

At sea level, ethyl alcohol boils at approximately how many degrees?

Answer 2

173 degrees Fahrenheit (78 degrees Celsius)

Question 3

The principle of the separation of two liquids with different boiling points is called?

Answer 3

Fractional distillation

Question 4

Which development marks the beginning of the history of modern distillation?

Answer 4

An 8th-century Arabic chemist-alchemist (Jābir ibn Ḥayyān) developed an improved alembic still—the precursor to the pot still—which allowed for a much purer distillation.

Question 5

Where does the name “alcohol” comes from?

Answer 5

“Alcohol” is derived from the Arabic al-koh’l, a cosmetic powder purified through distillation.

Question 6

What were the Arabs most interested in, in relationship to distillation, compared to Europeans?

Answer 6

The Arabs were mostly interested in the promise of alchemical and medicinal advances, but in Europe and elsewhere the allure of potable, powerful, and nearly indestructible distilled spirits soon became clear.

Question 7

Two types of still?

Answer 7

The more rudimentary pot still
OR
The more modern continuous still

Question 8

Name of the fermented liquor that goes into a pot still for distillation?

Answer 8

The wash

Question 9

How is heat applied to a pot still for the ethyl alcohol to vaporize?

Answer 9

Heat is applied directly to the vessel

Question 10

Upon being heated, what else vaporizes from the still’s vessel other than ethyl alcohol?

Answer 10

Congeners

Question 11

What are congeners?

Answer 11

Volatile molecules, such as esters, other alcohols, and aldehydes, which contribute to the flavors (or off-flavors) of a spirit

Question 12

What is the name used to refer to the first vapors to condense from the distillation process and why are they set discarded?

Answer 12

The foreshots. They are discarded as these contain congeners such as methanol, a toxic alcohol.

Question 13

Why are the tails also discarded?

Answer 13

They are discarded as unwanted congeners tend to collect in the distillate residue.

Question 14

A continuous still has two columns, what are they?

Answer 14

The analyzer
AND
The rectifier

Question 15

How is heat applied to a continuous still for the ethyl alcohol to vaporize?

Answer 15

A continuous still uses steam, rather than direct heat, to vaporize the alcohol.

Question 16

How does the resulting spirit from a continuous still differs from one coming out of a pot still?

Answer 16

In a continuous still, the alcohol is condensed in a purer fashion, stripping the liquor of excess congeners and creating a higher-alcohol spirit.

Question 17

What is the potential downside of using a continuous still depending on the desired outcome?

Answer 17

While congeners are responsible for impurities, they are also the source of flavor; thus, the continuous still sacrifices distinction (strips the spirit of excess congeners) for a clean spirit.

Question 18

What do most unflavoured spirits rely on for their final flavour?

Answer 18

The base fermented material and perhaps oak (if used).

Question 19

What are 4 techniques used for flavouring spirits?

Answer 19

1. Maceration (slower, cold method)
2. Infusion (quicker, hot method)
3. Percolation (base spirit pumped through flavouring material)
4. Artificial flavours and colour additives (lower-quality)

Question 20

Until 1980, Britain based its legal calculation of the alcoholic strength of liquor on a simple test. What was it?

Answer 20

The ability of gunpowder to combust when doused in the spirit.

Question 21

What is the American “proof” equivalent to?

Answer 21

American proof is twice the percentage of alcohol by volume (but is not required by law to be listed on labels) ex. 20% abv = 40 proof