Concentration of Wort Gravity by Evaporation Flashcards
(16 cards)
What percentage of water is typically evaporated during wort boiling?
Four to ten percent
This evaporation leads to a decrease in wort volume and an increase in concentration of dissolved material.
What is the term used for the gravity at the end of wort boiling?
Original Gravity (OG) or Original Extract (OE)
OG/OE is usually measured in degrees Plato (°P).
How is degrees Plato (°P) defined?
Percentage of extract by weight
In a 10°P wort, there are 10 g of extract in every 100 g of wort.
What does specific gravity (SG) indicate?
Density of a substance in relation to water
SG is a way to show how dense a substance is compared to water.
What is the formula for calculating density?
Density = mass/volume
Density indicates how much mass fills a specific volume.
What is the density of water at 4°C?
1.000 g/mL
This means that 1 mL of water weighs one gram at this temperature.
How do you calculate specific gravity if wort has a density of 1.060 g/mL?
1.060 g/mL divided by 1.000 g/mL
The specific gravity is a unitless quantity.
True or False: Specific gravity is a unitless quantity.
True
The units cancel out when calculating specific gravity.
What is essential for making consistent beer?
Achieving the target OG/OE
If OG/OE is too high, it affects flavor and microbiological stability.
What could happen if the OG/OE is too high?
Fermentation may stop early, leading to higher unfermented extract
This can affect both flavor and microbiological stability.
What is one method to achieve a consistent OG?
Control gravity at the start of the boil
This ensures the required amount of water is evaporated.
What factors must be consistent to achieve the desired OG?
Time, vigour, and heat input of the boil
Variations in these factors can affect the effectiveness of the boil.
What is the formula for calculating percentage evaporation?
Percentage evaporation = (boil volume - end of boil volume) / boil volume x 100
This formula helps determine the amount of water evaporated.
If the kettle contains 400 hL of wort at the start and 378 hL at the end, what is the percentage evaporation?
5.5%
Calculated as (400 hL - 378 hL) / 400 hL x 100.
Fill in the blank: The density of a substance is its mass divided by its _______.
volume
This relationship is key to understanding density.
What might be a practical limitation of measuring evaporation by kettle volume?
Variations in boiling conditions
This can affect the accuracy of measurements.
