Jump mashing Flashcards
(19 cards)
What is β-glucan composed of?
Chains of β-glucose residues cross-linked by proteins
What enzyme catalyses the hydrolysis of protein cross-links in β-glucan?
β-glucan solubilase
What is the optimum temperature for β-glucan solubilase activity?
60℃
What temperature is used to rest before cooling to 45℃ for β-glucan processing?
62℃
How long does the remaining β-glucan get processed by β-glucanases?
45 minutes
What problems does proper β-glucan processing help prevent?
Processing and haze problems associated with excessive levels of β-glucans
What is jump mashing primarily used for?
Production of low alcohol and alcohol-free beers
What is the initial temperature for the thick mash in jump mashing?
50℃
What is the water to grist ratio during the thick mash in jump mashing?
2:1
What temperature is the mash brought to after adding boiling water in jump mashing?
Around 74℃
How long is the mash held at around 74℃ during jump mashing?
Around an hour
What is the German term for jump mashing?
Springmaischeverfahren
Why is the fermentability of the wort low in jump mashing?
Because β-amylase is inactivated
What must be avoided to prevent increased fermentability of the wort?
Allowing the temperature to fall below 73℃
What type of glucans can remain in the mash due to the conversion temperature being above the optimum for α-amylase?
α-glucans (large dextrins)
What type of test might show a positive result due to remaining α-glucans?
Starch endpoint test
What should be ensured about the malt used in jump mashing?
It should be modified to the extent where the majority of β-glucans are degraded
Fill in the blank: The process of jump mashing involves a temperature jump from a proteolytic stand at 50℃ to over _______.
70℃
What is the final step in the jump mashing process?
Heating and mashing out
