Post on 28-Dec-2015
Dr. Lek Wantha
Beer Brewing
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Beer… Alcoholic beverage Fermented gains
Barley Wheat corn millet
Alcohol: 0.5-8 % alc. /w pH : 4.3 Sugar : 1.12% Protein: 0.33% CO2 :2.27%/vol.
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Beer Types… Lager
Bock Munich Pilsner
Ale Porter Stout Wiss
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Lager vs Ale beersLager Ale
Relatively new Thousands of years old
Fermented cold Fermented warm
Bottom fermentation Top fermentation
Yeast – Saccharomyces uvarum Yeast – Saccharomyces cervisiae
Longer brew cycle - up to several months
Quick brew cycle - as little as 7 days
Usually brewed between 4-13 ºC Usually brewed between 15-25 ºC
Smoother, crisper, and more subtle in taste and aroma
Strong, assertive, and more robust in taste
Served cold, 4-7 ºC Served not too cool, 10-14 ºC
(source: http://www.beer-faq.com/difference-ale-lager/)
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Materials Brewing Water Barley Malts Malt Adjunct Hops Yeast
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Materials: Brewing Water
90% of beer is water pH 7.5 50-100 mg/l CaCO3
55 mg/l of total water hardness <25 mg/l of permanent water hardness
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Materials: Barley Malts
Six-row barley Two-raw barley
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Materials: Malt Adjuncts
unmalted grains Corn Rice Rye Oats Barley Wheat
lower cost carbohydrate modify the flavor of beer
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Materials: Hops
Hop constituents %
humidity 12.5
ash 7.5
cellulose 13.3
aroma oil 0.4
tannin 3.0
total nitrogen 17.5
non nitrogen extract
27.5
Ether extract 18.3
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Materials: Yeast
top-fermenting Saccharomyces cerevisiae
bottom-fermenting Saccharomyces pastorianus Saccharomyces carlsbergensis Saccharomyces uvarum
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Brewing Process Malting Malt Milling Mashing Brewing Wort Boiling Fermentation Maturation Filtration Carbonation Pasteurization
Malting
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Beer Brewing
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Defect… Physical factors
Turbidity Light temperature
Biological factors Microorganism
Bacteria Acetobacter Lactobacillus pastorianus Flavobacterium proteus Bad smell (Hydrogen sulfide)
Zymomonas mobilis
Chemical factors Chemical reaction
protein
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References…
Goldammer, Ted. The Brewer’s handbook. http://www.beer-brewing.com/index.htm