Midterm Exam Flashcards
(20 cards)
Knows the basic role of malts in brewing and recognizes the existence of different kinds of malts.
Provide the fermentable sugars and enzymes necessary for fermentation, contributes to overall flavor profile, color, and mouthfeel characteristics
Base malts - two- and six-row malt, vienna, pilsen
Specialty malts - caramelized, non-caramelized, roasted
Can identify base vs specialty malts vs adjuncts.
Base malts: forms the foundation of a beer and provides most of the fermentable sugar (high diastatic power - starch is broken down effectively to produce sugar solution, converts starch to sugar, wort)
Two- and six-row malt
Vienna
Pilsen
Specialty malts: add unique flavor, color, and mouthfeel characteristics to the beer
Caramelized - special B, caravienna
Non-caramelized - aromatic, brown
Roasted - chocolate, black
Adjuncts: non-malt source of fermentable sugars to alter flavor, body, or color
Unmalted grains - wheat, barley, rye
Sugars - honey, maple syrup
Natural ingredients - fruits, pumpkins
Can associate styles of beer with specific kinds of malts and adjuncts.
English Ales: caramel and crystal malts add sweetness and color
German Weissbier and Weizenbier: wheat malts provides haze and banana/clove notes
Ales, Lagers, Pilsners, IPA, and Pale Ales: barley base malts
Stouts, Porters, and Brown Ale Beers: roasted malts for dark color and roasted flavors
American Lagers: corn and rice (lighten the body), two-row barley malt
Can describe the malting process and explain how different malts are produced.
Normal malts: steeping (2 days), germination (4-6 days), kilning (1 day)
Crystal malts: steeping, germination, roaster
Roasted malts: steeping, germination, kilning, roaster
Can calculate OG from PPG values for malts.
mass of extract x PPG = gravity points x volume of wort
gravity points = [(mass of extract x PPG) / volume of wort] / 1000 + 1
Knows the role of mashing in the production of beer.
Releases insoluble starch from grains and converts the starch to soluble sugars
Has general knowledge of how to get sugar out of malts.
Grind the grains and mix with hot water (mashing), where enzymes in the malt convert starches into fermentable sugars - grinding increases surface area, mashing activates enzymes for starch breakdown
Can describe the effect of temperature and pH on mashing and knows how to perform step mashes.
Temperature: the higher the temperature, the faster an enzyme will work, and the faster it will denature as it exceeds the preferred temperature range
Lower temperature favors beta-amylase and yields lighter-bodied, more attenuated beer
Higher temperature favors alpha-amylase and yields more dextrinous (contains more dextrins), less attenuated beer
pH: significant effect on yield and fermentability
< 5.0 severely diminishes beta-amylase activity and causes issues with wort clarity
> 6.0 increases silicates and tannin extraction from malt husks, affecting beer flavor
Step mash: first temperature rest at 147F for 30-40min followed by 162F for 15-20min
First rest for beta-amylase, second for alpha-amylase
Can calculate mash efficiency and brewhouse efficiency.
Mash efficiency: actual mashing achieves lower extraction of sugar
PPGactual/PPGmaximum x 100
Brewhouse efficiency: overall efficiency of brewing process in getting sugar out of grains and into the fermenter
(gravity points x gallons)actual in fermenter/(gravity points x gallons)potential for raw wort
Knows the role of different classes of enzymes in mashing.
Alpha-amylase: produces oligosaccharides, maltose, and glucose
Beta-amylase: hydrolyzes non-reducing end of starch to exclusively produce maltose
Limit dextrinase: cleaves branched alpha linkages in amylopectin
Beta-glucanase: hydrolyzes beta-glucans located in cell walls of barley endosperm into smaller units
Alpha-glucosidase: cleaves maltose and larger starch oligosaccharides into glucose
Protease: solubilizes insoluble barley storage proteins
Peptidase: produces free amino nitrogen from hydrolysis of soluble proteins
Phytase: catalyzes hydrolysis of phytic acid, releasing it into usable form of inorganic phosphorus (helps lower pH of mash)
Knowledge of classification of hops by region.
European
English
American
Southern hemisphere/pacific
Recognizes different roles of hop resins and essential oils in brewing.
Hop resin - bitterness (isomerized alpha acids, oxidized alpha and beta acids)
Essential oils - aroma and flavor
Flavor - combined impact of bitterness and aroma
Can match different kinds of hops to various styles of beers.
IPAs: american hops (citra, simcoe, mosaic)
Lagers: european hops (saaz, hallertau)
British ales: fuggle, east kent goldings
Can describe properties of terpenes, terpenoids, and thiols and their roles in hop aroma.
Terpenes (essential oil) - hydrocarbons of isoprene units; woody/spicy characteristics
Terpenoids (essential oil) - oxygenated terpenes; floral/fruity characteristics
Thiols - sulfur-containing compounds; exotic fruity aromas
Recognizes all variables in developing hop bitterness and flavor in beers.
Alpha acid content
Boil time
Boil gravity
Hop variety and amount
Utilization
Recipe volume
Can delineate major unit operations in beer production.
Hot liquor tank: heats water
Boil kettle: boiling with hops
Mash tun: mashing
Bucket fermenter (lauter tun, whirlpool, chiller): yeast inoculation and alcohol production
Can rank the order of the five most important factors in successful production of beer.
Sanitation
Fermentation temperature control
Yeast management
Boiling the wort
The recipe
Knows when and how to avoid microbial contamination during beer production and packaging.
Clean (alkaline or oxidizing cleaner), then sanitize (iodine or acid sanitizer)
Most important after the wort is cooled down (post-boil)
Everything before is sanitized from high temperatures of boiling
Boiling sterilizes the wort
Can describe bottle/keg conditioning vs forced carbonation.
Bottle/keg conditioning: relies on natural fermentation within a sealed container to create carbonation
Forced carbonation: uses pressurized CO2 to quickly carbonate beer in a keg
Knows when and how to avoid oxygen in beer production and packaging.
oxygen should be avoided after fermentation because it can cause stale flavors and reduce shelf life. oxygen is necessary before fermentation to help yeast, so aeration of the wort is done before pitching yeast.
minimize oxygen exposure: avoid splashing or agitation, minimize headspace in bottles/kegs, use closed transfer systems
