Spirits Production

Question 1

Copper (3 reasons)

Answer 1

1) easy to shape. 2) excellent conductor. 3) reacts with sulphur compounds removing from final spirit

Question 2

Temperature Gradient

Answer 2

temperature depends on proximity to heat source

Question 3

Reflux

Answer 3

happens when vapors and liquids mix. Vapors cool and fall back as liquid. When liquids and vapors mix heat is exchanged and the more volatile fractions become vapor less volatile become liquid

Question 4

Rectification

Answer 4

progressive increase in level of ethanol resulting from reflux

Question 5

Rectification Plates

Answer 5

maximize interaction between vapor and liquid (as few as 3 as many as 42)

Question 6

Head Condenser

Answer 6

cold water is circulated through an enclosed section in the top of the still. flow of cold water can be adjusting allowing control of amount of reflux

Question 7

Condensers

Answer 7

all stills, except for continuous stills, have condensers, where the spirit is drawn off as liquid.

Question 8

Condenser Part

Answer 8

1) Tube (where the water enters as vapor)

2) a coolant (typically water)

Question 9

Types of Condenser

Answer 9

1) Worm Tub (container for cold water and a single coiled tube)
2) Shell and Tube (number of narrow vertical tubes)

Question 10

number of rectification plates in a column still

Answer 10

15-42

Question 11

Bain Marie or Bagno Maria

Answer 11

Similar to Steam Jacket using water instead

Question 12

relationship between temperature and reflux

Answer 12

inverse

Question 13

height and shape of the head

Answer 13

height has a major impact of temperature gradient (obviously)

Question 14

Angle of the linking tube

Answer 14

if angled up reflux can continue

Question 15

Why add rectification plates and head condensers to pot stills

Answer 15

to allow distiller to produce more highly rectified spirits (can be bypassed)

Question 16

Double Pot Still Distillation: 1st distillation

Answer 16

separates all of the volatile fractions from some of the water and the non-volatile parts (solids). First distillation is not used for rectification or refining flavors. Collected as one product

Question 17

Double Pot Still Distillation: 2nd distillation

Answer 17

used for rectification and refining flavors. Collected as heads, heart, and tails

Question 18

Heads

Answer 18

contains high concentrations of volatile fractions with lower boiling points than ethanol (e.g. methanol). Can also be tainted by residue left in the still

Question 19

Heart

Answer 19

this is used to make the final spirit. It has high levels of ethanol and desirable congeners

Question 20

Tails

Answer 20

boiling point of liquid in the pot changes during distillation because the proportion of ethanol (with a lower boiling point) decreases. This means the boiling point increases (higher proportion of water) and less volatile fusel oils start to distill over.

Question 21

when to cut to tails?

Answer 21

early for a lighter spirit, Later cut will keep more fusel oils which give weight (e.g. peat character)

Question 22

Heat source for Continuous Distillation

Answer 22

typically direct injection of heat or a steam-powered heat exchanger known as a “reboiler”

Question 23

3 ways to promote reflux in a continuous still

Answer 23

1) equip with head condenser. 2) preheat alcoholic liquid by passing through a tube between the rectification plates. 3) pour some collected spirit back into the still to promote downflow

Question 24

Two “Stages” of Continuous Distillation

Answer 24

Analyzer/Stripper and Rectifier (analogous to 1st and 2nd distillation with double pot)

Question 25

Coffey Still

Answer 25

1830

Question 26

Multiple Column Continuous Distillation

Answer 26

even at 96%, some fusel oils, methanol, and congeners remain. Hydroselection and De-Methylising. both of these techniques work because the volatility of fusel oils and methanol vary according to the concentration of ethanol.

Question 27

Hydroselection

Answer 27

removes fusel oils. By lowering concentration of ethanol (by dilution to 20%) fusel oils become more volatile. Fusel oils rise to the top of still and diluted spirit is collected at the bottom.

Question 28

De-Methylising

Answer 28

removes methanol. Methanol is more volatile when ethanol concentration is 96%. Spirit is gently heated in a reboiler (steam would dilute) methanol is collected at the top of the still leaving purified, high-strength spirit behind

Question 29

Typical, five-column still

Answer 29

analyzer/stripper, rectifier, hydroselector, 2nd rectifier (to bring low-strength product back to 96%), and a de-methyliser

Question 30

Post-Distillation Operations

Answer 30

Maturation, Addition of Flavors, Blending, Finishing

Question 31

Oak Impact

Answer 31

1) can remove flavors either by evaporation or absorption (carbon on the interior of the barrel), 2) can add flavors. Vanillin, Lactones, Eugenol, ...

Question 32

Temperature/Humidity

Answer 32

determines abv fluctuations in aging spirit

Question 33

Weir

Answer 33

The function of a weir is to maintain desired level of liquid on a tray. Found on conjunction with Bubble Caps

Question 34

Bublecaps vs Sieves

Answer 34

If Sieve is used, pressure provided by upward movement of steam must be sufficient to prevent liquid from falling back down through holes in the sieve