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38 Cards in this Set
- Front
- Back
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deconstructing a beer |
-aroma- derived from ingredients such as malt & hops, but modified & augmented by yeast -head- from med-length proteins present in malt (& wheat,oats, rye). Affected by mashing & filtration -color-mostly from kilning of malts, but affected by mashing & boiling specs (& a bit ferm & filt) -carbonation- CO2, by-product of yeast ferm -body/mouthfeel- malt proteins affected by brew, ferm, and filtration -flavor- malt, hops, water affected by brew, yeast ferm -alcohol- more fermentable material = more alcohol |
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terroir |
-characteristics geography bestows through climate, soil, moisture, geology, micronutrients, & more -heirloom malts- Maris Otter, Halcyon, Golden Promise, Hana -noble hops-Saaz, refined char.of hops from trad. growing areas -water- usually altered now; Burton-on-Trent (dry plastery water) produced Dortmund Export; unique minerality incl. sulfur, carbonate & salt -wild yeast- local microflora inoculates beer, old cherry orchards S of Brussels harbored yeast, may reside in barrels |
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best brewer qualities |
curiousity, creativity, willingness to take risks, obsession w/ every tiny detail |
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water |
-called "liquor" when used for brewing -dissolves various minerals when in contact w/ soil, sand, rocks, etc (ions, 1/2 molecules) -not just taste, ions are chemically active effecting the brewing process -local waters limited styles (pre-1900) leasing to evolution (& regionality) of classic styles |
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limestone |
-mostly calcium carbonate -water w/ CO2 (acidic) dissolves it creating an alkaline (hard) water -gives hop bitterness an unpleasant astrigent bite & affects mash chemistry -only works w/ dark malts (also acidic) 7 low hop rate -ex: Munich & Dublin dark beers -hard water is very common |
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gypsum |
-calcium sulfate -less common mineral in water -19th century, Burtin-in-Trent, England well water worked well in new crisp, dry, very hoppy beer called pale ale |
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mineral-free water |
"soft" water -along w/ special mashing technique led to pilsner style -mineral-free water not suitable to most styles or brew methods, but its easier to add needed minerals than remove unwanted ones |
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good water for beer |
-free of: organic contaminents, pesticides, heavy metals, iron, sulfur -some minerals (not harmful to humans) can be toxic to yeast contributing to haze or unpleasant taste -iron gives bloody metallic taste needs: tiny amts of metals like copper & zinc vital for yeast nutrition -zinc is often added as yeast nutrient or copper materials used (pipes) |
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enzymes |
-specialized proteins that assist chemical reactions -for a chem reaction to happen, an energy barrier must be crossed (like lifting something over a wall); enzymes reduce the energy needed to change from one state to another |
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2-row vs 6-row |
-all malt beers commonly use 2-row -mainstream Amer beers use 6-row for additional enzymes used to break down starches in corn/rice, which lack their own enzymes kernels grow temp protein 2-row plump cool less 6-row less rotund warm more |
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barley |
-perfect brewing grain -large starch reserve to convert to sugar -husk makes filter bed -enzymes w/ ability to make reactions happen w/ modest heat input |
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Maillard chemistry |
-the chemistry of caramelization aka: non-enzymatic browning -includes all browning durin cooking ie: char on burger, golden sauteed onions, roastiness of coffee & chocolate -take some sugar or carb, combine w/ nitrogen-bearing material (typically from protein) & add heat in the presence of moisture... ...yields brown flavor, aroma & color |
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making malt |
1. Select high-grade barley & soak in water 24 hrs (45% water content)- rehydrates kernel & activates enzymes readying for growth 2. Place in cool place & keep aerated, seeds need oxygen. Rootlet appears & shoot called acrospire grows hidden under husk 3. When sprouting reaches a point (determines by length of shoot, aka modification) Most modern malt is fully-modified (shoot is full length of kernel) & can be easily mashed. 4. Wet, unstable, flavorless grains head to kiln. Indirect heat dries, then toasts it. Nearly all malt flour comes from kilning. |
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malting variations & results |
-every combo of sugar, starch & nitrogen (browning ingred.) produce different results -also, time, temp, pH, moisture level et al will create different flavor profiles -similar color malts w/ different moistures vary: dry-biscuity; moist-melanoidin, toffee, rich -brown beer could have large amounts of modest colored malts or a pinch of deep-roasted w/ varying flavor results |
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browning results |
color- melanoidins- large molecules w/reddish or yellowish cast & no discernible aroma -expressed in degrees Lovibond (US) or EBC (European Brewery Convention unit=1.97 Lovibond) - flavor & aroma- small ring-shaped molecules called heterocyclics (cont. elements such as sulfur, nitrogen or oxygen in hydrocarbon rings); potent odorants w. thresholds in low ppm range |
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base malts |
-kilned lightly enough to be used for the entire grain bill -serves as most of grain bill even in dark beers -color- 1.5-15 Lovibond -pilsner-palest available -pale ale-classic for pales & many other uses -Vienna- produces ambers like Oktoberfest -mild ale- classic base for dk. British beers -Munich- brews deep amber beer, sweet caramelly, hints of toast |
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kilned (color) malts |
-used up to 20% of recipe color is 15-200 Lovibond -aromatic/melanoidin/dk. Munich- brown & amber, sweet, caramelly -amber/biscuit- sharp, brown, toasty -brown malt- cassic for porters, smooth to sharp roastiness -pale chocolate- med-sharp roastiness, various uses |
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balance |
-subjective! -not simply hop vs. malt as some malts are bitter -toasty malty vs. hop bitterness vs. sweet malt -sour vs. sweet -contrast ---\ -harmony \------ artist/ brewer -layering /------ techniques -surprise ---/ |
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mashing |
-crushed malt mixed w/ hot liquor -enzymes convert starch to sugar resulting in "wort" -Crush quality is crucial! Too course=mash gives up too much sugar Too fine=husks are useless as filter bed -Several enzyme systems requiring optimal pH, mineral ions, concentration, etc -Some break down complex carbs in mash (glucosan, pentosan) -Some break down proteins into smaller parts- critical for yeast and to prevent haze and instability |
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fermentability of wort |
-2 enzyme system in mat- one creates highly fermentable sugars, the other less so -brewer can adjust fermentability of wort by varying mash temp -@145F- highly fermentable=crisp, dry beer -@155F- good proportion of unfermentable sugars- sweet, rich beer |
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mashing out |
once the grain is steeped in liquor, the temp is raised to end enzyme activity and lock ratio of fermentable to unfermentable sugars |
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mash procedures |
single infusion- hot water mix w/ grain. Stands 1 hour. step infusion- multiple smal steps are used to raise temp from room to nearly boiling; a few steps in English styles, more in Finnish sahti German decoction- 1/3 of mash in tun is removed, raised through series of steps & boiled briefly before returning to tun to create temp rise (1,2 &3 step versions); rare b/c of time & energy requirements, but adds layer of rich, caramelly flavors |
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lautering |
as wort is run off into the kettle, more hot water s added on top; typically takes place in lauter tun (vessel w/ perforated bottom) |
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hops |
a climbing vine in the nettle family related to marijuana -found its way to beer about 1000 years ago -cones are used (they are not flowers) -cultivated @ 35-55 latitude N&S as specific summer day lengths trigger cone production -vulnerable to pests, disease tied to specific locations -Saaz- spicy, orange soil, Western Bohemia -Hollertau- northern Bavaria -EKG- twangy, green, spicy, SE of London 100+ varieties, but US brewers can only get 1/3 |
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hop plant parts |
-small internal stem (strig) holds leafy parts of cone together -around strig are tiny globules of lupulin, a pungent, waxy substance containing bitter resins & aromatic oils -Resins divide into alpha & beta acids -alpha acids contain bittering power ranging from 2-20% |
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aromatic hop varieties |
characteristics fall into national groups: -German- herbal, sometimes minty -English- spicy to fruity, fresh green grassiness -Saaz- clean, spicy -American- great variety, piny, resiny |
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noble hops |
European hops usually used for aroma in lagers chemically defined requirements used to limit the nobles to 4, but requirements have been adjusted to retain exclusivity traditionally, Saaz, Hollertau, Tettrunger, Spalt |
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high-alpha hop varieties (& dual-use) |
-to increase bitterness -sold by alpha acid pounds -Americans have seized grapefruity varieties like Chinook & Colombus Dual use hops- some hops combine moderate alpha levels w/ pleasant aromatic qualities |
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the boil |
1. sterilizes wort, prevents takeover of bacteria & wild yeast 2. isomerizes hops, making them more bitter & soluble 3. coagulates excess protein w/ help from tannins 4. ends enzyme activity & locks in sugar ratio 5. direct-firing of kettles may also add some caramelization |
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primary fermentation |
-specific amoutn of healthy yeast is added to oxygenated wort -yeast takes in oxygen (only during yeast budding should oxygen contact beer) and begins "budding" off new cells -when oxygen is depleted, yeast turns to wort: 1st-glucose (single sugar), 2nd- maltose -creates head & heat, takes 1 day to 1 week dep. on temp, wort strength, yeast vigor, etc. -3rd, yeast works on maltotriose (process slows) -yeast sensitive to temp, tank depth & geometry, nutrient mix, # of cells per unit, oxygen |
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lager yeast |
Saccharomyces Pastorianus -ferments @ 40-45F & conditioned at nearly freezing -clean, pure flavor w/ fruity/spicy aromatics -bottom-fermenting |
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ale yeast |
Saccharomyces Cerevisiae -top-fermenting -more genetic variations than lager yeast -ferments well above 55F -fruity, spicy esters & high alcohols & phenolic compounds |
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specialized yeast (& bacteria) |
-hefeweizen- Torulaspora delbrueckii -Belgian saison- poss. related to red wine yeast, thrives @ temp <90F; low ester, high phenol; black pepper spicyness -brettanomyces-barnyard, horsey aromas; metbolizes maltose; used in lambics, some saisons & English old ales -Pichia & Candida-film-forming yeast, minor in lambics; also spoilage organism -Lactobacillius & Pediococcus- sour lambics & Berliner weisses, can create a lot of diacetyl & goaty, sweaty socks aromas -Acetobacteria- alcohol +02=acetic acid; vinegar/pickle aroma; may also create ethyl acetate; common in oak-aged beers; important to lambic aromas & esp. Flanders reds & browns |
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fining |
-process used to speed up clarification of beer -some gelatinous or other substance is added to pull down yeast & other flotsam -isinglass (dried fish bladder) is traditional in England -gelatin & special plastic microspheres (PVPP/Polyclar) |
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filtration |
can remove finest particulates & bacteria, however, too tight & it will filter out color, hop bitterness, body, & head-forming compounds -cold-filtration & centrifuges avoid these problems, but are expensive -too early filtration can lead to "green" beer aromas esp. acetaldehyde & diacetyl |
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hop usage |
-vigorous boil essential for isomerization (hop alpha acids rearranged chemically into more bitter, more soluble form) -longer boil=more bitterness, up to 2 hours -vigorous boiling drives off hop aromas, later additions are necessary to retain aroma -1+ "flavor additions" can be made adding bitterness & aroma to boil -hop backs (percolators) loaded w/ hops, then hot wort runs through on way to chiller -Dy-hopping= after fermentation |
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pasteurization (& flash-pasteurization) |
-finished beer heated for short time @ high temp to kill remaining yeast & bacteria, typically 2-3 min @ 140F -improves shelf-life over filtered, unpasteurized beer -some studies show that a "cooked" flavor can be detected by experts -flash-pasteurization- kinder to beer flavor, 15-30 sec @ 161-165F |
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common packaging issues |
-oxidation- stale, cardboardy; too much oxygen, poorly sealed caps -chlorophenol- band-aid aroma; incompletely rinsed sani -skunk- clear or green bottles offer no light protection; -Tetrahop is a processed hop bittering extract w/ offending "skunk" precursor removed; may also improve foam stability |
