Murphy & Son Limited – FAQs - Beers Quality in Cask

Murphy & Son Limited
Alpine Street
Old Basford
Nottingham, NG6 0HQ

Tel: 0115 978 5494
Fax: 0115 924 4654
email: info@murphyandson.co.uk

Faults in Cask

Hazes in cask can arise from:
Yeast, wild yeast and/or bacteria in the beer
Floc particles in the beer due to poor settling of the finings or too much sediment in the cask
Unflocculated protein or starch particles
Incorrect level of Carbon Dioxide in the beer

Nature of the Problem: Primary yeast haze
	Possible Cause	Possible Remedy
FAULTS IN FINING	Incorrect rate of addition of finings	Refine. Optimise addition rate of Isinglass finings. Measure the strength of the isinglass. Check operation of finings machines and adjust if necessary.
	State of finings	Adjust preparation and storage conditions of finings. Check the age of the finings.
	Speed of fining too slow	Check addition rate of finings. Adjust operation of finings machines. Check beer pH and Viscosity.
	Incorrect yeast count at rack	Measure and adjust yeast count at rack.
FAULTS WITH THE YEAST	Health of yeast cells	Check for dead or wasted cells. Replace culture.
FAULTS IN THE BEER AT FINING	Beer temperature	Adjust the temperature of storage.
	Beer condition	Check yeast count and actual attenuation. Measure carbon dioxide content.
	Beer pH	Check beer pH. Check and adjust liquor treatment.

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Nature of the Problem: Haze caused by wild yeast and/or bacteria
	Possible Cause	Possible Remedy
FAULTS IN PROCESS	Microbial contamination of the brewing plant	Check cleanliness of all vessels, hoses, mains and cocks.
	Incorrect detergent concentration	Adjust according to Manufacturers instructions.
	Inadequate cask washing	Check operation of cask washers, detergent concentrations and inspection regime for washed casks.
FAULTS IN THE BEER	Beer pH	Check beer pH. Check and adjust liquor treatment.
	Residual FAN & fermentable sugars	Measure FAN & fermentable sugars. Check mashing temperature and/or malt specification.
	Sulphur dioxide level too low	Measure sulphur dioxide levels in the beer & if low increase sulphur dioxide levels in the finings.

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Nature of the Problem: Non biological haze
	Possible Cause	Possible Remedy
FAULTY PRECIPITATION OF PROTEINS	Inadequate wort boiling	Check copper breaks, copper finings, mashing procedures, malt nitrogen specification and copper performance/% evaporation
FAULTY PRECIPITATION OF PROTEINS	Chill haze	Adjust beer storage temperature.
FAULTS IN FINING	Auxiliary fining rate too low	Check rate of addition and operation of finings machines. Try alternative auxiliary, eg Silicate, alginate, polysaccharide, blend.
	Beer temperature	Adjust beer storage conditions.
	Beer condition	Check yeast count and actual attenuation.
	Fining speed too slow	Check rate of addition of copper finings, Isinglass finings and auxiliary. Check operation of finings machines. Try alternative auxiliary, eg Silicate, blend.

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Nature of the Problem: Volume of sediment too high or insufficient compaction
	Possible Cause	Possible Remedy
FAULTS IN FINING	Copper fining rate incorrect	Check copper breaks, optimise additon rate.
	Addition rates of Isinglass and/or auxiliary incorrect	Optimise addition rates. Check operation of finings machines.
	Incorrect yeast count at rack	Check yeast count at rack. Adjust rousing, time of skimming or attemperation rate.

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Nature of the Problem: Failure to resettle in Trade
	Possible Cause	Possible Remedy
FAULTS IN PROCESS	Incorrect fining rate	Check and optimise rates of addition and operation of finings machines.
FAULTS IN PROCESS	Incorrect Cellar management	Refer.
FAULTS IN THE FERMENTED WORT	Insufficient fermentable residues	Measure concentration of fermentable sugars. Adjust using primings if required.
FAULTS WITH YEAST	Low yeast viability	Check yeast viability. Replace culture.

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Nature of the Problem: Inadequate condition
	Possible Cause	Possible Remedy
POOR SECONDARY FERMENTATION	Insufficient fermentable sugars	Measure fermentabilty limit. Adjust attenuation of primary fermentation. Adjust rate of primings addition. Check mashing conditions.
	Low yeast count/viability	Measue yeast count and viability. Adjust cooling of primary fermentation or conditions of centrifuge. Replace yeast culture.
	Low storage temperature	Measure and adjust temperature of storage.

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Nature of the Problem: Excess condition
	Possible Cause	Possible Remedy
FAULTS IN FERMENTATION	Incorrect attenuation in primary fermentation	Check actual attenuation limit. Improve attemperation control. Check mashing regime.
FAULTS IN FERMENTATION	High yeast count at rack	Measure yeast count. Adjust cooling of primary fermentation or conditions of centrifuge.
FAULTS IN PROCESS	Over addition of priming sugars	Adjust rate of primings addition
FAULTS WITH BEER	Temperature of storage too high	Adjust temperature of storage.

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