Grain Whisky Flashcards
grain distilling
continuous distillation
why cont dist?
-high rectification ( means to produce a pure ethanol conc)
production
derived from a mash containing approx 90% unmalted cereral
in case of the flow diagram, at an equal stage to malt whisky production. grain and neutral spirits are produced after fermentation and they are further processed into alternative spirits and then packaged to be traded.
grain whisky produced less characteristic whisky and is hence predominantly used for blends.
Grain vs Malt
Produced more ( that is because it acts as a base for many blends )
goes beyond only malted barley and uses other cooked , unmaled cereals like barley, maize, wheat
It is produced at approx 94.8 as compared to malt that stands at 69
also, has a low congener concentration as compared to the high congener concentration in the malt whisky.
Grain whisky vs GNS
85-90% grain | 100% grain
no exo enzymes| permitted
<94.8% abv| <96.8% abs
matured for at least 3 years ( grain whisky) and produced in accordance with the scotch whisky act | cannot be called scotch whisk and no mat.
whisky - GNS feedtsock for malt whiskies.
GNS - tight volatile epecifications ( mathanol, diacetyl etc. )
Distillation column.
consists of analyser and rectifier with plates. refer to diagram on board.
Every plate is 1.5 pot distillations - reason why it is so rectified and concentrated.
2 still (analyzer and rectifier)
American, candian, light rums - not purely restricetd to GNS or grain whisky.
Coumn distillation of Grain whisky
refer to flow diagram
GL
Gay lusac ( scale)
Theory of Continuous Distillation
- based on difference of volatality
- Units to be expressed in percentage of alcohol for excise and duty purposes
- The ethanol-water system graohs can be used from 0 to 97.2 % ethanol ( which is the azeotropic point ) A
- At this point the percentage of alcohol in vapour at atmospheric pressure is equal to that in the liquid.
At a temperature below the bubble point the two comp exist only as liquids and at temp above the dew point they both exist as vapours.
Sieve plates
- designed to collect low level of liq on plate area ( mostly 5cm)
- holes to be sufficiently small so that upward vapour velocity can be prevent weepage but sufficently lrge to prevent blockage ( holes 9-12mm)
In rectifier ( smaller holes)
coloumn design
- Weir
- down comer
- overflow cup
- Sieve plate
Weirs
- surrounds downcomers
- prevents vapour from flowing up the downcomers
- lcontrol level of liquid on the plate
factors to choose sieve plates
- cost
- solids?
- type of feedstock
- relative yield and efficiency
difference in running of beer still
whisky ( 30C, less therml degradation, 12-14 plates)
GNS ( 85C )
18-22 in stripping section , lower losses
Fuel alcohol ( 100C , max recovery of ethanol)
fuel alcohol isnt drunk , so max can be taken in.