Sweet Wort Production (Methods & Plant) Flashcards
What is a isothermal mashtun and what is it used for?(6)
Combined mashing in, conversion and wort separation vessel
They can only used well modified malt
No facility for mixing and heating
Isothermal (single temperature)
No heating jackets
Ideal for small operations, not particulary suitable for large batch productions
What can happen if all the starch isn’t converted in the mash?
Washes out during sparging into the kettle where it can gelatinize and be carried through the brewing process to form hazes in the final product
What is a cereal cooker?(5)
Decoction system
Used to boil mash of maize or rice
Enzymes which are stable and active at 80c plus (boiling)
Returned to MCV then to lauter
Can be avoided by adding pre-gelantinized maize or rice in the form of flakes, these can be put straight into a MCV
What happens to the starch in the MT?
Broken down and converted to sugars
What happens to proteins in the mash?
They are broken down into amino acids
What is a hammer mill?(3)
Maybe used if the mash is to be separated in a mash filter
Here the filter bed is very thin and husk protection isnt neccessary
Produces a very fine grind giving good wetting, subsequently enzyme activation and rapid extraction of the sugars from thr particles
To the eye what should the grist look like?
Large pieces of husk, small pieces of white grist and little flour
What is a wet mill?(3)
May be used for lager production
Husk receives extra protection because it is steeped in water before milling proceeds
Typically these only have a single pair of rolls
The less well modified the malt the finer it needs to be ground, and the faster the extraction process,the finer the malt has to be ground
TRUE or FALSE?
True
Husk and other particles contain tannis and lipids which will make the beer unstable, reduce the head and go stale
TRUE or FALSE?
True
The purpose of wort separation is to separate the sugars in the wort and malt residues from the husks ect
What is the cause of these problems?
- Run-off problems
- Excessive volumes of trub / high hazes
- Flavour problems
- Fermentation problems (e.g. due to smothered yeast in extreme circumstances)
- Variable yeast flocculation
- Poor filterability
- Potential shortening of shelf life due to haze formation
Due to high hazes in the wort
What are 4 roll mills?(2)
Often used for well modified malts where starch is readily available
Adequate for mash tun operations
What will unfermentable sugars do to the finshed beer?
These sugars will contribute to the desired mouthfeel of the finished beer
Mineral salts, vitimins, lipids, fatty acids and amino acids all contribute to beer how?
Allow healthy yeast growth
What will proteins in the wort do to the final product?
Help for foam
What happens to the pH in the mash?
It drops
What is a lauter tun and what is it used for?(3)
Converted mash is transferred from the MCV to the lauter tun
Will give good wort quality and extract recovery
Recirc the cloudy wort
What is a mash conversion vessel (MCV) and what is it used for?(5)
Fitted with heating and stirring facilities
Can be mixed to ensure homogeneity
Less well modified malt can be used here because different temperature stands can be used
Has to be transferred to a lauter tun or mash filter for recovery of the wort
MCV may also be linked with a separate mash cooker, or cereal cooker
What is a 6 roll mill?
Often used for milling less modified lager malts where the starch needs to be finely ground to allow rapid wetting in the mash vessel
What does effective wort separation mean?(2)
Maximising extract recovery
Absence of particles and starch in the wort
What is a 5 roll mill?
Very similar to a 6 roll mill
These are less commonly used than 6 roll mills, as there is little financial gain
What is a mash filter and what is it used for?
Numerous plates and frames, which overall form a very large area of very thin beds
Rapid turnaround times and high extracts are achievable
Enable a very fast run-off of wort and effective sparging
Some filters have membranes built into the plates which allow the cake to be squeezed and thus obtain a slightly higher yield and drier cake than non-membrane pressess
A modern mash filter is a series of polypropylene filters
What is a mash tun and what is it used for?
Acts as a conversion and wort separation vessel
Wort may be recycled on top of the mash until clear, to remove the fine solids but can blind the bed so usually not carried out
Filtration gives a very bright wort through a deep bed
Is slow and extract recovery is moderate
What is a 2 roll mill?
Most commonly used by smaller brewers
The grist composition cannot be as accurately controlled compared to those produced by 4 or 6 roll mills
