a) Cloudiness is usually a product of proteins in the finished beer or (for some styles) suspended yeast. Chill haze is a common clarity issue where the beer is clear when warm and cloudy when cold. This is due to polyphenols (derived from tannins in grain and hops) combining with larger proteins (from the malt and adjuncts). These compounds are soluble at warmer temperatures and insoluble at cooler serving temperatures. These can be removed through the use of low-protein grains in the grain bill, possibly performing protein rests, boiling to get better hot break, chilling rapidly to get good cold break, using Irish Moss in the boil, and using finings (such as polyclar) in the finished beer. Cold conditioning can also reduce chill haze over long periods of time, and filtering the beer can as well. There are two other main sources of chill haze, called biological haze and chemical haze. Biological haze is due to bacterial infections or suspended yeast. The bacterial problem will likely cause other, more severe issues with the beer and the only way around it is good sanitation practices. The suspended yeast issue can be solved only with time, or by choosing a more flocculent yeast. Chemical haze is caused by inadequate calcium in the brewing water (lower than 50 ppm) or excessive iron or copper levels in the water. Different water choices or supplementing the water supply with gypsum, calcium chloride, or chalk can help alleviate this problem. As a final note, some beers actually are cloudy as part of their profile: particularly German hefeweizen and Belgian witbier. If recipes for these beers do not produce the desired haziness, the grain bill may need altering (toward more wheat), or a few tablespoons of flour can be added at the end of the boil (to introduce larger proteins and starch to the wort).

b) Butter/Butterscotch (diacetyl) is a compound which produces a buttery aroma and taste in beer. Diacetyl is a common yeast by-product during fermentation. During later stages of fermentation most diacetyl is reduced to an odorless and flavorless compound. The following factors increase diacetyl in beer: worts with high sugar and starches, deficient amino acids, weak yeast, excessive oxygen in the wort. Diacetyl can be decreased with healthy yeast populations, choice of yeast strain, and warmer fermentation temperatures. Note that in some beers diacetyl is not bad, so long as it amounts to nuances and compliments the overall character of the beer. Some commercial examples of beers which have diacetyl in some amounts include Red Hook ESB, some English bitters, and even Pilsner Urquell.

c) Poor Head Retention is due primarily to the absence of small and medium sized proteins in beer. Extract brewers are largely dependent on their extract for the protein level, although they can do some things to improve head retention such as using steeped crystal malt (around ½ lb to 1 lb). Allgrain brewers can help control this by their choice of grain and their mashing regime. Different malts have different protein levels; for example, domestic 6-row malt is higher in protein than pale ale malt. Also, adjuncts such as flaked wheat can increase head retention, as can the aforementioned use of crystal malts. The protein rest (steeping the grains at temperatures around 130 F) has been rather controversial; some sources believe it is actually detrimental to head retention, and is not needed in the first place. The protein rest is designed to reduce the size of proteins in the wort, and thus it is possible that they can be reduced to the detriment of head retention. There are other factors that can decrease head retention: high levels of alcohol in the beer and oily or dirty serving glasses can also reduce head retention.

d) Mouthpuckering is another description for astringency, but sour/acidic notes can come into play as well. See the answers for h and j below.

e) Band-aid like (phenolic) tastes come from a few different sources, but are described as medicine chest-like flavor and aroma, Band-Aid like, or plastic-like or clove-like. The clove flavor in Bavarian wheat beers is due to a desirable phenolic compound. Chlorine contamination of beer can cause phenolic taste, either from high levels in the water or from poor rinsing of sanitation solutions. Some yeast strains promote phenolics (i.e., Bavarian wheat beer strains), so proper yeast selection and avoiding contamination from wild yeast is important. Poor sparging techniques can contribute to phenol formation, including water which is > 170 F, oversparging, and pH > 6.0. Care in sparging will reduce these causes.

f) Light body is also largely a product of proteins in the beer. The proteins that generate good head retention can also generate a heavy, full or chewy mouthfeel. Again these can be controlled by the grain types and the mashing regime as in (a). Other sources of heavy/full mouthfeel include high-gravity beers (controlled by the amount of grain or malt extract in the recipe), lower attenuation (controlled by higher mash temperatures, choice of malt extracts, or choice of yeast as some yeast strains are more attenuative – create more alcohol and lower final gravities- than others), and malto-dextrin powder, an additive that adds unfermentable carbohydrates to the beer. Conversely, low mouthfeel and body can be produced by excessive or unnecessary protein rests, some adjuncts such as rice or sugar, highly attenuated beers, and bacterial infections. Highly carbonated beers can also seem to have lower body, as can lighter (lower OG) beers.

g) Fruitiness is caused by fermentation by-products called esters. Esters are produced from acids and alcohols. Different yeast strains produce esters in different amounts. Bacterial infections can also produce esters, although they usually produce other effects that are not as pleasant. Higher fermentation temperatures cause more esters, as does underaeration (insufficient oxygen), underpitching, and high levels of alcohol. Some levels of esters are good in many types of ale.

h) Sour or Acidic tastes are usually caused by infection with bacteria. Lactobacillus, pediococcus and acetobacter are the most common bacterial contaminants. The back of the tongue contains taste buds which perceive sourness in foods. There may also be a tart or vinegar-like aroma. Sanitation is important to preventing contamination. In addition, using a good strain of yeast will minimize the amount of bacteria which can grow. Other contributing factors for sour taste include too much citric or ascorbic acid used to adjust wort pH, fermentation at high temperatures, excessive acid rest, long mashes, and storing beer in a warm environment. Using correct temperatures for beer fermentation & storage will reduce. Timing the mash process and measuring pH are also important.

i) Cooked Corn aroma/flavor in beer is caused by Dimethyl Sulfide, or DMS as it is commonly called, is a strange sort of creamedcorn, celery, or vegetable aroma. It is caused through two main ways. First, there is a compound called S-methyl methionine (SMM), which is a product of malt germination. Different malts have different levels of SMM and can cause DMS to appear in differing amounts. For example, beer made many European pilsner type malts can have problematic amounts of DMS unless steps are taken to reduce its level. North American 6-row malts have approximately 10 times the level of SMM than English or Belgian 2- row malts. Generally, the darker the malt the lower the SMM. The other source of DMS is a bacterial infection. DMS can be avoided in beers brewed from troubled malts through a few easy steps. Leaving the lid off the boiler during a boil can reduce DMS. Extended boiling periods, for example 90 minutes instead of 60, can also reduce DMS. Supposedly, slow wort cooling can also cause DMS to remain at excessive levels. It should be noted that some levels of DMS are not regarded as flaws in pale lagers. Some Kolsch style ales also have small levels of DMS.

j) AstringenCY in beer comes primarily from tannins in grains. Tannins are mostly found in the husks of grain and in hops, but may be the result of contamination by wild yeast or bacteria. In the latter case, sanitation can help prevent this character. Astringency is perceived by the entire mouth, as a puckering, dry sensation (like grape skins, or young wine). Tannins are extracted from grains when the water reaches the boiling point; thus removing grain prior to boil will help prevent. When grain is over-crushed, there is more exposure of the husk to water, which allows a greater level of tannin extraction. High sparge temperatures (> 170° F) or over-sparging will also increase the level of tannin extraction, as will water which is too acidic. Excess minerals (sulfate, magnesium and iron) contribute to astringency in this manner as well, so close monitoring of water characteristics is also necessary. Finally, over-attenuation will result in less sweetness to balance astringency, so using a yeast variety which is appropriate to the beer style you are hoping to brew will help reduce this characteristic.

k) Cardboard taste is usually due to oxidation of fermented beer. Also referred to as wet paper, sherry like and rotten fruit. This character may be in both the aroma and the flavor. Things that can contribute to oxidation include aeration during transfer or bottling, low fill level in bottles, age (especially if bottle cap is not tight), heat in storage, temperature fluctuation during secondary fermentation or lagering, or adding tap water to finished beer without boiling. Steps that reduce the exposure of beer to oxygen once yeast has been added to fermenter are important to reduce this character, including: not splashing during transferring beer, using carbon dioxide in bottles to flush out oxygen, consistent fermentation and storage temperatures for beer.

l) Sherry-like aromas are caused by the process of oxidation acting on melanoidin products in the wort (melanoidins give beer its color and some malt character.) This reaction produces aldehydes that can also include winey aromas, rotten vegetable, and baby diaper aromas. The primary cause is introducing oxygen after the initial yeast pitching. There is also some belief that introducing oxygen earlier can produce unpleasant effects as well. This phenomenon is called hot side aeration (HSA) and occurs when warm wort is splashed during the transfer from mash tun to boiling vessel. We can reduce the amount of oxidation by careful handling of the beer. Only aerate or shake the beer just prior to addition of yeast; all other times carefully avoid this handling. In truth, the effects of oxidation take time to manifest themselves so if you drink your beer 2 weeks after you bottle and it is all gone in two weeks (!) you probably won't ever find a problem, but keeping beer for the long haul requires careful processing to reduce the effects of oxidation.

a) Cidery flavors are sometimes referred to as "green apple", or acetaldehyde. This flavor develops from yeast metabolism during fermentation. As beer ages, this character usually decreases. Some bacteria will contribute to the formation of this flavor, so sanitation is important to reduce this flavor. Cane or Corn sugar will contribute a certain amount of cidery flavor to the beer, so limiting the use of these as fermentables is a good idea. While it is important to oxygenate the wort when pitching yeast (so they can grow well), oxygen introduced at other times will contribute to these off flavors.

e) Skunkiness (contrary to Budweiser commercials that purport skunkiness as a character for canned beer) is caused when light waves of certain types hit finished beer. This is an odor and a taste and should never be present in beer. Fermenters should be protected from light at all times. Bottling in dark brown bottles is preferred to clear or green bottles, as the brown glass will block most of the offensive light waves. Fluorescent light contributes to skunking also, so avoid this in your brewery.

There are really two ways to differentiate between aroma and bittering hops. The first way is simply their time of application. Aroma hops are added late in the boil (the last 1 to 5 minutes) to add hop aroma to the beer. These late hop additions add some flavor. Sometimes aroma hops are steeped at the end of the boil. On the other hand, bittering hops are added early and are often boiled long periods of time (up to 60 - 90 minutes) to add bitterness only. This usage of hops occurs in virtually every beverage we call beer, even those styles that do not feature much hop character. The other way to differentiate between aroma and boiling hops pertains to hop characteristics. Generally, a preferred aroma hop has good characteristics of aroma and is often low in alpha acids, while a bittering hop has higher alpha acid content. Other compounds called hop oils contribute to hop aroma (and flavor); keys among these are humulene and myrcene. Aroma hops tend to have more humulene than myrcene, while in bittering hops the situation is reversed. A hop that is fine for aroma can be used as a bittering hop and vice-versa. There will be some drawbacks to this approach: namely, high alpha hops may not contribute the best aroma characteristics and low alpha aroma hops used for bittering may require large quantities to get the desired bitterness in the beer.

Some examples of aroma hops include the noble hops (Saaz, Tettnanger, Hallertauer, Styrian Goldings) and some English varieties like Fuggles and East Kent Goldings. Bittering hops include Galena, Cluster, Northern Brewer, and Nugget hops.

If you want to go the extra mile you could also add details about hop oils and resins. Chemicals called hard resins and soft resins cause hop bitterness. These resins comprise approximately 15% of the hop mass. Soft resins include Alpha acids (humulone, cohumulone, and adhumulone), Beta acids (lupulone, colupulone, adlupulone), and other compounds.

The alpha acids are the most important in this regard. When they are boiled in the wort they undergo a structural change called isomerization and change to compounds that are soluble in the wort and give the beer bitterness. Beta acids also undergo isomerization but their compounds are not as soluble so they do not contribute as much to the bitterness of the wort. Clearly, then, hops used for bittering are chosen based on their alpha acid content.

Flavor and aroma in hops come from compounds called hop oils. These hop oils are an even smaller constituent of the total hop mass than the bittering compounds (around .5 to 2% of the total mass). Over 250 different chemicals in beer can be traced to hop oils. Probably the four most important compounds are myrcene, humulene, caryophyllene, and farnesene.

Myrcene is the largest component of hop oil in many types of hops, comprising between 20% and 65% of the total oil. It is frequently characterized as pungent. Hops highly praised for aroma characteristics tend to be low in their myrcene content (noble hops, Fuggles, East Kent Goldings) and primarily bittering hops tend to have more myrcene (Nugget, Galena, Brewer's Gold). Degradation products of myrcene include linalool and geraniol; these compounds tend to be perceived as floral. Citrusy and piney flavors and aromas also come from many myrcene compounds such as citral and nerol.

Humulene is described as having elegant flavor and aroma characteristics. It is found in higher amounts in the noble hops and lower in bittering hops. For example, Saaz oil typically has 40-45% humulene while Galena has 15% or less humulene. Humulene degradation products are described as herbal or spicy and include humulene epoxides and humuladienone.

Caryophyllene and farnesene are rather small components of all hops (5 to 15%) although they tend to be higher in aroma hops than bittering hops. Farnesene compounds are not well characterized. Caryophyllene compounds are also not well characterized but it is known that caryophyllene epoxide is associated with herbal characteristics.

This question pops up in all exams. It is necessary to know the BJCP beer style guidelines to answer this question correctly, but we can summarize some of the style information along with some ideas and rules of thumb to determine the recipes.

The answer should contain 7 parts that are easy to remember if you think of them as following from the beer conception to completion:

1. Description of the beer style
2. Grain bill and explanation
3. Mashing schedule and explanationHop bill and explanationYeast choice and explanation
4. Fermentation schedule and explanation
5. Conditioning, serving, other details and explanation

Note that the parts require "an explanation" because you need to explain why you chose these ingredients.

For starters, the short answer (one that satisfies the question) is in bold. This features a simple name for the brewery / monastery, where it is, and two good examples to use. For a more detailed answer to this question we reveal as much as we can about the monastery breweries in Europe in general and in Belgium in particular. In a real exam you will likely increase your score if you do this, but be sure to keep track of time and first answer the question exactly - only go back and add more if you have time later. The flavor profiles listed are based on Michael Jackson's reviews. This is a good strategy as his opinion is highly regarded and a good reference point.

The Abbaye de Notre-Dame d'Orval in Villers-devant-Orval, Belgium produces Orval. The oldest monastery of the six, local legend says that a princess promised God she would build an abbey if she recovered a ring lost in a nearby lake. A trout brought the ring to the surface. This event is depicted on the label of each bottle of Orval. Orval restarted brewing in the 1930s and is responsible for petitioning for the legal appellation of Trappist.

Orval: Produced with 3 malts, white candy sugar, Hallertauer and Styrian Golding hops, and a very distinctive yeast. Alc 6.2% by vol. Dry hopped with Styrian Goldings. Beer has an earthy aroma and a very dry acidic palate. Some sage like notes are evident.

The Abdij der Trappisten in Belgium produces the Westmalle beers. The abbey was founded in the late 1700s, began brewing for its monks in the early 1800s, started selling the beer locally around 1870, and became a full-fledged commercial brewer around 1920. Brewery uses summer barley from France and a wide range of hops, focusing on Tettnanger, Saaz and Styrian Goldings. Dubbel OG 1063 6% ABV reddish dark brown color; soft body; sweetish malty chocolate flavor with hints of raisins and bananas Tripel OG 1080 9% ABV dense white head, herbal aroma with hints of thyme and coriander; clean flowery-fruity palate, almost citrusy. Delicate dry hop character and clean firm maltiness.

The Abbaye de Notre-Dame de Scourmont in Forges, Belgium produces Chimay (pronounced she-may). This monastery was founded in the mid 1800s and popularized the term "Trappist biers" between WW II and I. The modern Chimay beers were shaped through the efforts of Father Theodore who worked with famed Belgian brewing scientist Jean De Clerck.

• Red (identified on the label in French as Capsule Rouge) OG 1063; 7% Alc by volume; Big bodied with spiciness and hearty robustness; house character (certain spicy, fruity black currant and juniper like aspects) very evident. Reddish brown in color.
• White (Capsule Blanche) also known as Cinq Cents, to mark the 500th anniversary of the town of Chimay in 1986. Pale, peachy color; OG 1071 8% ABV, dry with hoppiness evident which eventually drops with age.
• Blue (Capsule Bleue) also known as Grand Reserve. OG 1081, 9% by vol. Grand Reserve often refers to the strongest beer brewed by a brewery. Blue has peppery notes and is very spicy, similar to port after about 5 years aging.

The Abbaye de Notre-Dame de Saint-Remy in Rochefort, Belgium produces Rochefort. Originally a convent, the brewing started in the late 1500s using barley and hops grown on the grounds. The Rochefort abbey and brewery were restored in the late 1800s after damage from Napoleonic forces. The abbey and brewery were rather reclusive until recently so their products were not widely known. Pilsner and Caramunich Malt from France, Belgium, and the Netherlands is used with dark candy sugar and an aromatic blend of German and Czech hops, along with two strains of yeast both during primary fermentation and during bottle conditioning. Each beer is identified by its original gravity in Belgian measurement units.

• Rochefort 6 (red cap) 7.5% Alc by vol pinkish-brown; perfumy, sweetish and fruity, hints of basil and teas
• Rochefort 8 (green cap) 9.2% Alc by vol brownish, similar to 6 but more assertive; fig like notes in aroma.
• Rochefort 10 (blue cap) 11.3 % ABV, deep red color, dense head, spicy earthy aroma with hints of chestnuts, candied fruit, bittersweet chocolate.

The Abdij Koningshoeven in The Netherlands produces Schaapskooi, also known as La Trappe. The brewery was founded in the late 1800s to help finance the building of the monastery. The brewery produces several beers under the name "Koningshoeven" for local cafes.

• Dubbel OG 1066, 6.5 ABV deep ruby color, complex flavor with hints of chocolate, sherry, prunes, licorice
• Tripel OG 1070, 8 ABV bronze color, good hop character with hints of coriander, malty
• Quadrupel OG 1086 10% ABV; released in autumn & vintage dated; russet color, smooth texture, fruity spicy palate, lingering tart dryness in finish

The Abdij Saint Sixtus in Belgium produces Westvleteren. After WWII until 1992 the monastery licensed a nearby brewery to produce a range of beers under the name of Saint Sixtus. The brewery itself dates from the 1830s. The beers are made in a traditional manner using first runnings to produce a strong beer and second runnings for lower-gravity brews. Northern brewer hops are used along with pale malt and white and dark candy sugar, and Westmalle yeast. The brewery only operates once a week and sells the bottles marked only by the color of the bottle cap. Each beer is identified by its original gravity in special Belgian measurement units.

• 4 degree: (green crown top) gold in color, light and dry. Some hop bitterness is evident at the end of the tasting. (4.5% by volume)
• 6 degree: (red top) ruby color with hints of chocolate and plum in flavor; some dryness in the finish.(6.2% by volume)
• 8 degree (blue top) dark reddish color, sweeter and fruitier than the 6 degree; big rocky head (8% by vol)
• 12 degree (yellow top) dark amber-brown in color, creamy aroma (?) and toffee flavors (11% by volume)

Brewing has been associated with monasteries for centuries in Europe. A famous example of a brewery producing a particular style is the Doppelbock beer Salvator brewed by Munich Pauline monks. Since monasteries were basically self-sustained communities who tried to produce all the items they needed for themselves, and beer was a vital part of their diet, it is only natural that monks made their own beers. This tradition continues today among monks of some orders in Austria and Germany. Usually, these beers follow the styles of their countries. However, some monasteries of the Trappist order in Belgium and the Netherlands have developed distinct beers with some common characteristics. These beers are wonderful and are highly respected among beer enthusiasts for their uniqueness and challenging flavors. They are all top fermenting beers; bottle conditioned; and strong. They also vary greatly in other aspects, including their flavor profiles (some re dry, but many tend to be sweeter) and complexity. Some utilize candy sugar in the kettle, resulting in interesting flavors that highly compliment their overall character. Altogether, the six monasteries produce over 20 beers.

An interesting commonality to some of these breweries is the "single, double, triple" variety of beers. The single refers to lighter, dinner-type beers which the monks drink everyday. The singles tend to be rather limited commercially, probably due to the limited capacity of the breweries and competition with secular breweries. The double and triple varieties are stronger; the terms refer to degrees of strength but not literally.

Although there are several breweries that produce beers inspired by these beers, they must carry the appellation "Abby" for legal reasons (and hopefully out of respect as well!)

Mashing accomplishes conversion of proteins and starches to smaller sugars that can be fermented by yeast. Smaller proteins also contribute to head retention. Stages include acid rest (about 20 minutes) at 92F to get the proper pH set (around 5.2-5.5) for optimum enzyme activity. Next is protein rest around 122 f for 30 minutes so proteases can splice longer proteins down to shorter more desirable ones. Next is starch conversion around 148-155 (around 1.5 hours) to allow alpha and beta amylase to break down starch molecules to sugars (saccharification) so they can be fermented by yeast later. Beta amylase prefers lower temperature; alpha amylase prefers higher temperatures. Beta amylase tends to produce more fermentable drier wort, while alpha amylase produces sweeter less fermentable wort, though yeast is important in this equation as well.

Single infusion mash is performed by solely performing the saccharification step; generally this is done by adding a measured quantity of hot water to the grain. This procedure is recommended on highly modified malt, which has less protein content. The single infusion mash is generally thought of as an English process since malt produced classically by that country is more modified.

Step infusion mashing undergoes the additional prior protein rest and possibly the acid rest as well. The initial step is produced by adding a measured quantity if hot water, then additional steps are produced by heating the kettle. The acid rest is often skipped, depending on the chemistry of the brewing water and the type of malt used. Step infusion, along with decoction mashing (discussed next) are German procedures.

Decoction mashing is very similar to step infusion. The steps are produced by pulling a portion (about 1/3) of the "thick" part of the mash, heating it to saccharification temps (around 150-156) and resting for about 20 minutes, then heating it to boiling for 15 minutes. The grain is caramelized and darkens considerably. In the process a chemical reaction occurs that produces melanoidins in the wort. This decoction is added back to the main mash and mixed thoroughly, raising it to a new rest temperature. A single decoction generally is used between protein rest and sacc temps; a double from acid-protein and protein- saccharification; and a triple decoction adds a third step, a sort of high temperature saccharification. The pulling of the decoction should use the thick part of the mash to leave the enzyme rich liquid of the mash behind for starch & protein conversion. German in origin, the decoction mash is used for lower quality grain with lower enzyme levels to increase extraction rates. There is some controversy about whether decoctions make a large difference in the flavor of the beer; seemingly, German or Moravian malt (Munich malt and pilsner malt) reportedly benefit the most from this difficult procedure.

THIS QUESTION OR SOME VARIANT IS ON EVERY EXAM! So it pays to know this one. The BJCP is an independent non profit organization of beer judges formed in 1985 by the AHA and HWBTA (Home Wine and Beer Trade Association). Over 1500 judges are currently active. The BJCP promotes beer literacy and the appreciation of real beer as well as recognize beer tasting and evaluation skills. Judges must pass a 3 hour exam that features 2 parts; essay, worth 70% that covers technical aspects of brewing, beer styles, and the BJCP; and tasting, worth 30%, covering the tasting and scoring of 4 beers just as in a competition setting. 6 main levels of judges (use the All Real Cruds Never Make Goodbeer mnemonic to help you remember this if necessary)

• Apprentice-take exam but failed to score over 60
• Recognized score 60
• Certified score 70 and 5 xp (experience points), at least 2.5 judging points
• National 80 and 20 xp, at least 10 judging
• Master 90 and 40 xp, at least 20 judging
• Grand Master 1st Degree; min of 90, 100 xp at least 50 judging. Service requirement needed as well, determined by BJCP board of directors in individual basis. Additional degrees earned in 100 xp increments with add service requirements.

Judges are declared inactive if 2 years pass without earning any experience points. If another 2 years pass the judge is dropped from list.

Experience points are earned judging, organizing, or helping run competitions that are BJCP registered or AHA sanctioned. Judges earn .5 pt per session (uninterrupted time period where one or more flights of judges review beers), with a minimum of 1 pt per comp and max of 1 pt per comp day. The number of Best of Show (BOS) judges depends on he number of beers in the BOS round as follows: 5-15 beers 3; over 15, 5.

(This type of style question appears often. Usually these questions either require the candidate to compare and contrast two (or more) radically different styles or very similar styles. Another example I remember from my exam was to compare the Bohemian Pilsner and Dry Stout.)

These beers have a commonality in that they are all pale colored European lagers. A good general differentiator between the group is that Pilsners balance toward hops, the Helles tend toward malt, and the Export is balanced. The Pilsners are made from soft water (low levels of minerals), with the Bohemian Pilsners water being very soft. Conversely, the export is brewed from very hard water (high levels of minerals). This difference in water character shows in the beer flavors in that the hard water intensifies the hop bitterness in a manner that is not reflected in the bitterness measurements - as a result, the Export has a long, lingering bitterness, while the Pilsners tend to be more smooth and less lingering. All these beers feature noble hops.

There are three main substyles of pilsner. The first, Bohemian Pilsner, is the main influence on the other light lager styles. Its aroma features a complex malt and spicy, floral Saaz hop character. Its flavor is more complex than the other varieties. A major technical detail of its brewing is the use of the soft water of Plzen in the Czech Republic, which tends to soften the hop flavors. Another key element, at least of Pilsner Urquell, is the decoction brewing method whereby portions of the mash are boiled to raise the overall mash temperature to different rest temperatures. Pilsner Urquell is a prime commercial example.

The Old Thunder Road at Calhoun's and the Pils at Great Southern are similar to this style as well. The second pilsner type, the Northern German Pilsner, is drier than the Bohemian Pilsner due to differences in malt, hops, water character, and attenuation. The aroma features grain and distinctive, flowery 'noble' hops. Its color is lighter than the Bohemian Pilsner. The hop bitterness dominates the flavor profile, and can be quite intense in some examples. Warsteiner, Bitburger, and Beck's are three good examples of the style.

The final Pilsner sub-style is the Scandinavian-Dutch Pilsner, which is similar to German Pilsner but with somewhat lower original gravities, a drier flavor, and lighter palate, and a lower hop character. Some brewers of this style use rice or corn adjuncts. Heineken and Grolsch are examples of this style.

The Munich Helles style is a Bavarian light lager. The beer balance is malty with just enough hops to balance the sweetness of the malt. The beer is less attenuated than a Pilsner and thus fuller-bodied. The color is also a bit darker than a Pilsner. The Helles (meaning pale) is very similar to the Munich Dunkel style; it is made with pale Pilsner-style malt while the latter is made with darker Munich-style malt. Paulaner Premium Lager is a primary example. (You can also taste an award-winning Helles at Calhoun's, the Velas Helles.)

Finally, in the Dortmunder Export malt and hops are balanced for a smooth yet crisply refreshing beer. Not as 'sweet' as the Munich Helles style, but not as 'bitter' as the Northern German style and a bit stronger than either one. This beer is brewed from very hard water. Some commercial examples include DAB Export and Dortmunder Union Export, in addition to Ron Downer's Golden Eagle Lager at Rocky River (also available at Barley's from time to time.)

For this question I have tried to provide specific yeast strains by their commercial designation when possible. I have done this because basically I think it will impress the grader, and for the most part I have tried to abstain from using bizarre, off-the wall strains. Indeed, if you have brewed a variety of beers and experimented with different strains you can probably recall your own experiences. Also, I have listed seven considerations as it never hurts to "go the extra mile" in the exam, especially if you have the time during the testing session.

Attenuation:Attenuation refers to the ability of the yeast to convert the sugars in the wort to alcohol. Some yeast strains are better at this behavior than others, with the less attenuative producing less alcohol and sweeter beers. More attenuative strains produce drier beer, with more alcohol. It should be noted that other factors influence these characteristics, notably the original gravity of the beer and the mash schedule. An example of a good attenuator is Wyeast 2042 (Danish Lager, 73-77%), and a lesser attenuating strain is White Labs WLP005, British Ale (67-74%).

Optimal fermentation temperature:Generally lager beers operate best at cooler temperatures, while ales perform better at warmer fermentation temperatures. Lager beer yeasts produce cleaner beer with far fewer esters, but take longer to complete and often require extensive aging at near freezing temperatures. Again this is a complex interaction; a lager yeast can behave very ale like if the fermentation temperature is too high, and some (though not all) ale yeasts can exhibit lager-like characteristics at lower temperatures. An example of a warm fermenting strain is White Labs WLP001 California Ale (68-73 F), and a cooler strain is Wyeast 2124 Bohemian Lager (46-54 F).

Ester production:coupled tightly with fermentation temperature, esters are the compounds that produce fruity notes in beers. However, two different ale strains at the same temperature can produce very different esters in the same wort. Some strains (like Wyeast 1214, Belgian Ale) produce notes reminiscent of bubble gum, while others (Wyeast 1318, London Ale III) are more wine-like and lemony.

Phenol production:phenolic yeasts are commonly used in Bavarian wheat beers (particularly homebrewed versions). A strain with large amounts of phenols is White Labs WLP300, which is characterized as producing clovey, banana-like notes in beers.

Flocculation:flocculation refers to the ability of the yeast to settle to the bottom of the fermentation vessel. Most beers need good flocculation, but not all yeast strains do this well, and it is often a trade-off between getting good flocculation and achieving other desired characteristics. Some beers even seek poorly flocculating yeast; an example of this is Belgian wit beer, with recommended strains WLP400 and Wyeast 3942. An example of a highly flocculent yeast is Wyeast 1318, London Ale III.

Diacetyl production / reduction: diacetyl is a product of fermentation and creates buttery, butterscotch flavors and aromas in beer. Most strains produce diacetyl, and the ability to reabsorb the produced compounds is an important consideration . Many lager beers undergo a diacetyl rest, a slight raising of the fermentation temperature for a few days to help the yeast reabsorb produced diacetyl. However, some beers (particularly examples of commercial beers) have noticeable diacetyl as part of their character, as a result of their yeast strain and fermentation regime. Wyeast 1028 London Ale is a fairly significant diacetyl producer.

Appropriateness for style:Finally, some beers belong to certain styles of beers, especially when the style is virtually a copy of a classic commercial beer. A few examples are Wyeast 2278 or WLP800 for Czech pilseners; Wyeast 1056 or WLP001 for American ales (said to be the Sierra Nevada strain used in their Pale Ale); and Wyeast 1338 for Belgian strong ales.

(As always, this answer will contain more detail than probably necessary, as this increases your score.)

Different oxidized compounds produce different effects. Probably the most common effect is a papery, cardboard aroma produced from the oxidation of melanoidins. The melanoidins are wort constituents formed from malt. Their oxidation produces aldehydes. Other compounds and their oxidized counterparts are listed below, with their sources in parenthesis.

• Vinegar-like (from acetic acid formed from the oxidation of ethanol)
• Winey, sherry, rotten vegetables, cardboard (from aldehydes formed from the oxidation of melanoidins)
• Stale, cheesy (from the oxidation of hop alpha acids)
• Sagebrush, hay like, moldy (from oxidation of hop oils)
• Soapy, sweaty (From oxidation of lipids and fatty acid)

The main source of oxidation is likely simply handling. Aeration or shaking of the beer should be done only just prior to addition of yeast. During the course of bottling the beer and transferring it from carboy-to-carboy or carboy-to-keg, it is inevitable that some splashing will occur, which causes oxidation. Some homebrewers who keg their beer try to minimize the effects by purging air out of their kegs or carboy with a blast of carbon dioxide gas.

Another controversial source of oxidation is something called "hot-side aeration". This is an aeration of the wort during mashing or sparging – essentially anytime before the boil. Those who believe this is an issue theorize that the hot wort causes oxygen to react with melanoidins early, and these changes are then made and rear their heads weeks later when the beer is finished, typically as sherry-like aromas. Others believe this is not an issue at all. Regardless, it is probably prudent to try and minimize splashing of the wort at all times, except just before pitching yeast.

For this question, we will give the water profiles of the cities in question. I think for an actual exam, you would not have to remember the exact levels but probably the relative levels and what is unique about the water. For an extra-credit we’ll briefly touch on water treatment techniques for homebrewers.

In general, brewers track the mineral content of water through the following ions:

• Calcium (Ca) Calcium is important for all-grain brewing, as it is said to lower mash pH and is important for many enzyme reactions.
• Magnesium (Mg) At low levels, Mg is a yeast nutrient; at high levels it can cause a laxative effect (i.e., "Milk of Magnesia") Just the thing for beer, huh?
• Sodium (Na) accentuates flavor, but may be harmful to yeast in excessive amounts, and can be unpleasant in very high concentrations.
• Carbonates (CO3) increase mash pH and can interfere with yeast flocculation. High carbonate levels in all-grain brewing can cause astringent (puckering and drying effects) on beer, because the increased pH can extract excessive tannins from the grain husks.
• Sulfates (SO4) High levels contribute to a long, lingering hop bitterness in beer.
• Chlorides (Cl) accentuate sweetness, help in clarification and smooth bitterness.

Burton On Trent:     Ca: 280    Mg: 55    Na: 40    CO3: 250    SO4: 680    Cl: 30

The water of Burton-On-Trent is famous for being extremely hard, with high levels of calcium and sulfates. The pale ales of Burton-On-Trent feature an accent on hoppiness; the hoppiness is accentuated by the sulfates in their water.

Dortmund:     Ca: 240    Mg: 35    Na: 65    CO3: 365    SO4: 200    Cl: 80

Dortmund water has high calcium, carbonate and sulfate levels, although the sulfates are not nearly as high as Burton-On-Trent. Some authors have noted that Dortmund beers are malty and sweet (Michael Jackson); others say they are well-hopped and accent hoppiness, directly from the water profile (Papazian and Korzonas). Fix may have the real solution; Dortmund brewers are regarded as early pioneers in water treatment technology, so it may well be that they mastered the sciences of water treatment for a long period of time.

Dublin:     Ca: 115    Mg: 4    Na: 12    CO3: 200    SO4: 52    Cl: 19

Famous for stouts: dark, malty ales with moderate bitterness. Lower levels of sulfates moderate the bitterness of hops and drying effect.

Munich:     Ca: 90    Mg: 19    Na: 2    CO3: 160    SO4: 45    Cl: 18

Famous for dark, malty lagers. Lower levels of sulfates moderate the bitterness of hops and drying effect.

Pilsen:     Ca: 7    Mg: 2    Na: 2    CO3: 15    SO4: 5    Cl: 5

The water of Pilsen, in the Czech Republic is famous for being extremely soft. It has very low levels of just about every mineral. Pilsen is famous for pilsner beers, with high hop levels that are intense but do not linger.

Other cities:

Homebrewers can treat their water to emulate these different waters depending on their own water content. For example, in our hometown of Knoxville TN our water profile is very similar to that of San Francisco CA. Thus we are ideally suited to emulate those brewing waters with little or no treatment at all. Common chemicals used to treat water are:

• Distilled water (to reduce the level of all ions by diluting the "original" water)
• Gypsum (calcium sulfate; 1 gram in 1 gallon of water increases Ca by 62 and Sulfate by 148)
• Epsom Salts (Magnesium Sulfate; 1 g in 1 gal of water increases Mg by 26 and SO4 by 102)
• Chalk (Calcium carbonate: 1 g in 1 gal of water increases Ca by 106 and CO3 by 158)
• Table Salt (Sodium chloride: 1 g in 1 gal of water increases Na by 104 and Cl by 160)
• Anhydrous Calcium Chloride ( 1 g in 1 gal of water increases Ca by 95 and Cl by 169)

It should be noted, of course, that many brewers in these modern days treat their water! Thus, as noted by Fix in "Principles of Brewing Science", the city of Dortmund produces beers that are on the sweetish, malty side, which is not consistent with the flavor profile of water from that city. It is likely not a coincidence, however, that those same breweries were in the forefront of water chemistry technology for brewing science. Thus, in emulating a Dortmund beer, it is probably not a good idea to try and treat your water to mimic Dortmund water; Fix believes mimicking Pilsen water would be a better choice.

In general, however, the best path a homebrewer can take is to not treat their water at all. If the water tastes OK to drink, it is probably OK to brew with and should produce good results for many different beer styles.

A note on "Burton brewing salts": this is a commercial product that is actually a blend of chalk and gypsum. It is designed to mimic Burton water, but the problem with its usage iseveryone’s "starting water" is different.

Although originally all beers were cloudy, today only a few styles are accepted by the beer-buying public as cloudy (notable wheat beers). Most commercial breweries achieve clarity through filtration, but there are simpler methods available to homebrewers through the use of additives. These clarifying additives are called "finings". Their main role is to help precipitate whatever elements (polyphenols, proteins, or yeast) that cause the beer cloudiness.

Irish Moss: This is a red seaweed which should be rehydrated, ideally for 24 hours, before use. It is added during the boil for the last 15 minutes. About ¼ teaspoon is needed for a medium-strength beer, going up to ½ teaspoon for higher gravity brews. Irish moss acts by helping coagulate proteins through electrostatic action; its charge in the brew is opposite that of proteins, so the two are attracted and settle out easier.

Silica Gel: This works by absorbing proteins as it sinks down in the fermenter; thus it is added when fermentation is over. About 10-20 grams are suggested. Silica gel is used in conjunction with filtering in commercial breweries; using it in unfiltered beer is kind of new territory, so it should definitely be decanted off the bottom through racking to an additional fermenter. Generally the gel works very fast, but a 1-2 day wait is recommended before performing a final racking of the beer.

Bentonite: Bentonite is a clay-derived substance that is gray and powdery. It should be added to water before use as a clarifying agent. To make a bentonite slurry, take approximately 2 oz of bentonite powder and add to a quart of boiling water. About two tablespoons of this slurry can be used as a clarifying agent in the fermenter. (The rest of the bentonite slurry can be set aside for future batches of beer, provided it is kept sealed and clean.) Bentonite works by absorbing proteins and is good for combating chill haze; some recommend its use as a partner to polyclar (see below).

Polyclar: This is the trade name for PVPP, polyvinylpyrrolidione (that’s a mouthful!) which is really a plastic powder. It works in the fermenter through electrostatic action. As such it does not attract proteins, only polyphenols, and thus does effect head retention in beer. It may also slightly reduce the bitterness of the beer. About 4-6 tsp mixed in a cup of boiling water can be added in the fermenter and allowed to settle out for about 2-5 days.

(As an aside: there are three main sources of haze in beer, chemical, biological, and chill haze. Chemical haze must be removed by changing your water; usually it is caused by excessive amounts of tin, iron, or copper or insufficient calcium. Biological haze is caused by yeast or other agents like bacteria that may not actually spoil the wort or beer. Chill haze is probably the most common, and is caused by protein / polyphenol compounds.)

In the 1999 BJCP guidelines there are 9 beer styles that utilize wheat as a major ingredient, and an additional one that has wheat up to 25%. Here we will mention all these and feature a very brief synopsis of the style; more detail can be found in the BJCP descriptions.

American Wheat: This beer is often 50% wheat malt or more. A light, refreshing beer that exhibits balanced hop and wheat maltiness. The aroma is characteristic of wheat with some graininess, with neutral yeast aromas (no clove/phenols as in Bavarian wheat beers.) Hop aroma may be high or low but if present will be from American hop varieties. Appearance is usually pale straw to gold, but dark versions approximating Dunkel Weizens are acceptable. The flavor features light graininess, with low to high hop flavor. Hop bitterness low to medium. Some fruitiness from ale fermentation acceptable. Light to medium body. Higher carbonation is appropriate. Mouthfeel will appear lighter than actual body due to higher levels of carbonation.

OG: 1.035-1.055    IBUs: 10-30    FG: 1.008-1.015    SRM: 2-8    ABV: 3.7-5.5%

Anchor Wheat is a good commercial example.

Bavarian Weizen: Typically 50% or more of the grist for this style is malted wheat, the remaining being pale malt. Overall this beer is a pale, spicy, fruity, wheat-based ale. The aroma features vanilla and clove-like phenols and fruity esters of banana from the strains of yeast used, with hop aroma ranging from low to none. The color is pale straw to dark reddish-gold in color. A very thick, long-lasting head is characteristic. High protein content of wheat may impair clarity in an unfiltered beer, and clarity can be deliberately cloudy in a Hefe-Weizen from suspended yeast sediment. The filtered Krystal version is quite clear. The soft, grainy flavor of wheat is essential. Hop flavor is low to none and hop bitterness is very low. A tart character from yeast and high carbonation may be present. Spicy clove phenols and fruity esters, most prominently banana, are often present. For mouthfeel, the texture of wheat imparts the sensation of a fluffy, creamy fullness that may progress to a surprisingly light finish. A high carbonation level is typical.

OG:1.040-1.056    IBUs:10-20    FG: 1.010-1.014    SRM: 2-9    ABV: 4.3-5.6%

Paulaner Hefe-Weizen is a good commercial example.

Bavarian Dunkelweizen:A dark, malty, spicy, wheat-based ale. Wheat malt typically makes up 50% or more of the grist, the remainder being Munich or Vienna-type high-kilned barley malts. The aroma contains a gentle hint of Munich malt supported by fruity, notably banana, and clove-spice aromas. No hop aroma. The beer is light amber to light brown in color. A thick, long-lasting head is characteristic. High protein content of wheat may impair clarity in an unfiltered beer. The flavor features melanoidins and caramel character of Munich and Vienna-type malts, along with some wheat flavor. There may be some spicy, fruity flavor as well. Roasty character is rare and very restrained if present. Low hop bitterness. No hop flavor.

OG: 1.040-1.056    IBUs: 10-20    FG:1.010-1.014    SRM: 10-23    ABV: 4.3-5.6%

Schneider Dunkel Weiss is a good commercial example.

Berliner Weisse: A very pale, sour, refreshing, low-alcohol wheat ale. Wheat malt content is typically well under 50% of the grist, the remainder being pale barley malt. Lactobacillus delbruckii culture and fermentation provides the sharp sourness, which may be enhanced by blending of beers of different ages during fermentation and by extended cool aging. The aroma is slightly fruity; a soured aspect may be quite noticeable. No hop aroma. The appearance is very pale straw in color, and clarity ranges from fair to cloudy. Despite high carbonation, head retention can vary from moussy to low. In flavor, lactic sourness dominates and can be quite strong, but some wheat flavor should be noticeable. Hop bitterness is very low.

OG: 1.026-1.036    IBUs: 3-8    FG: 1.006-1.009    SRM: 2-4    ABV: 2.8-3.6%

The 2 main examples of the style are Schultheiss Berliner Weisse, Berliner Kindl Weisse.

Weizenbock:A strong, malty, fruity, wheat-based ale. Wheat malt is typically 50% or more of the grist, the remainder barley malts. Weizen ale yeasts are used. A powerful aroma of ripe fruit is very common. Aroma of alcohol is also common. Some clove-spice aroma may be present. No hop aroma. The appearance is light amber to dark brown in color. High alcohol level may impair what would otherwise be a thick, long-lasting head. Wheat protein content may impair clarity. Concentrated wheat flavor is dominant. Malty complexity, including smoky or raisin-like essences, may be present in darker versions. A fruity character is common, and some clove-spice flavor may occur. Well-aged examples may show some sherry-like oxidation as a point of complexity. Hop bitterness is well controlled to allow wheat and malt flavors to dominate the balance. No hop flavor. No diacetyl. The beer is full-bodied. A creamy sensation is typical, as is the warming sensation of substantial alcohol content.

OG: 1.066-1.080+    IBUs: 15-30    FG: 1.015-1.022    SRM: 7-25    ABV: 6.5-8.0%+

Schneider Aventinus is the first example of this style.

Witbier: A refreshing, elegant, complex, wheat-based ale. About 50% unmalted hard red winter wheat and 50% pale barley malt constitute the grist. Spices of freshly-ground coriander and dried orange peel complement the sweet aroma. Ale yeast prone to production of mild, clovey/spicy flavors are very characteristic. the aroma features a sweet and occasionally honey-like character with prominent citrus (notably orange), herbal and spice aromas is characteristic, and is often followed by a mild phenolic aroma. Hop aroma is low to none. Very pale straw to very light gold in color, and generally cloudy. Head retention should be quite good. The flavor of unmalted wheat is typically noticeable. Coriander, citrus and mild phenolic flavors contribute to a complex and elegant character. A very slight lactic acidity may be present in some versions. Hop flavor is low to none. Hop bitterness is typically restrained, and some bitterness may also be contributed by bitter orange peel. Light to medium body. Effervescent character of high carbonation.

OG: 1.042-1.055    IBUs: 15-22    FG: 1.008-1.012    SRM: 2-4    ABV: 4.2-5.5%

Some commercial examples include Hoegaarden Wit, Steendonk Witbier, Bruges Tarwbier, Blanche de Bruges.

Straight (Unblended) Lambic-Style Ale: Complex, sour, pale, wheat-based ales fermented with a variety of microflora. Unmalted wheat (30-40%) and aged hops are used. The aroma of these beers is a complex blend from a wide variety of microbiota, often described in the following terms: horsey, horse blanket, sweaty, oaky, hay, and sour; other subtle aromas are enteric, vinegary and barnyard. Yellow to gold color. Young examples are intensely sour. When aged, the sourness is more in balance with the malt and wheat character. Bottled lambic ales vary from well-carbonated to not carbonated, and draft lambic is virtually flat. Traditionally, these beers are spontaneously fermented with naturally occurring yeast and bacteria in oak or in some cases chestnut barrels.

OG: 1.044-1.056    IBUs: 10-15    FG: 1.006-1.012SRM: 4-15ABV: 4.7-5.8%

Very few straight (unblended) lambics are bottled. Most commonly available is Grand Cru Cantillon Bruocsella 1900. I

Gueuze/Geuze-Style Ale: Gueuze/geuze is traditionally made by blending lambic that ranges in age from three years to less than one year and then bottled. Typically, gueuze/geuze has a smoother palate than straight lambic. For the most part, with these exceptions, the BJCP style description matches that of straight unblended lambic. Some commercial examples are Boon, Cantillon, Lindeman's, and Boon Mariage Parfait.

Fruit Lambic-Style Ale:Intensely refreshing, fruit-flavored, complex, sour, pale, wheat-based ales fermented with a variety of microflora. In younger vintages, the fruit with which the beer has been flavored should be the dominant aroma. In old bottles, the fruit aroma typically has faded and other lambic aromas are more noticeable. In appearance, the variety of fruit determines the color. The flavor is similar to the gueuze with fruit flavors present; these fruit flavors are simpler and more one-dimensional in young lambics (the fruit added being dominant) and more complex in the older examples. A very faint astringency is acceptable, like wine, but no more than a well-aged red wine. These beers are commonly made by blending two- or three-year-old straight lambic with young (less than 1-year-old) straight lambic, after which fruit is added for further fermentation and aging before bottle-conditioning with very young straight lambic. Fruits commonly used for flavoring are cherries (Kriek) and raspberries (Framboise), although more recent commercial examples include peaches (Peche), grapes (Vigneronne or Muscat) and black currants (Cassis).

OG: 1.044-1.056 (plus the fruit)    IBUs: 10-15    FG: 1.006-1.012    SRM: 4-15    ABV: 4.7-5.8%

Some commercial examples include Cantillon Kriek, Cantillon Gueuze Vigneronne, Boon Kriek Mariage Parfait, Framboise Marriage Parfait. The BJCP guidelines left out Lindeman's, probably because many judges feel these beers are too sweet for this style, but in many places (i.e. Knoxville) these are the closest thing you can buy for this style.

Koelsch-Style Ale:Although not required, small amounts of wheat may be used (<25%). Thus this style should be used for this question only if you have time to add a 4th style, or if you cannot think of the others. True Koelsch must be made in Cologne, Germany. Koelsch-style ales feature a light hop aroma from German noble or Czech Saaz hops and low to no maltiness. Koelsch is a lagered beer with a clean finish; however, since primary fermentation is done at ale temperatures, a hint of fruitiness is OK. The beer is very pale to light gold, and very clear, with a lingering white head. The flavor is soft with a light hop fruitiness and a delicate dryness to slight sweetness in the finish. Medium-low bitterness. Balanced toward bitterness but malt character should not be completely overshadowed. Overall, a delicately balanced beer with just a hint of flavor/aroma hops and fruitiness that finishes dry to slightly sweet with a crisply refreshing bitterness over a base of smooth, rounded Pils malt flavor.

OG: 1.040-1.048    IBUs: 16-30    FG: 1.008-1.013    SRM: 3.5-5    ABV: 4.0-5.0%

Body and mouthfeel refer to sensations of thickness / thinness in beer related to unfermentables remaining after complete fermentation and condition. As extreme examples, pure water would be very thin, and whole milk would be very full. Beers fall in between these extremes, of course, and a light American beer like a Coors would be thin, while a heavy beer like a Mackeson’s XXX stout would be full bodied. The original gravity of a beer does not always correlate directly with high body and mouthfeel. The final gravity is a more direct measurement although it is not necessarily the only component of mouthfeel. The carbonation content of a beer can also influence the drinkers’ perception of mouthfeel and body. Finally, tricks such as serving the beer with nitrogen or through a beer engine “sparkler” can alter perceptions of mouthfeel as well.

Regardless, the body and mouthfeel of a beer can be influenced by a variety of parameters that a brewer can control. First and foremost is the attenuation of the beer; a more attenuated beer will generally have less body than a less attenuated beer. This factor can be influenced by mashing temperature, choice of yeast, and use of adjuncts like cane sugar. Second is the composition of the grist. For example, flaked wheat is often added in small amounts to beers that are traditionally not wheat-based to add a level of body through proteins. Another example is oatmeal, which can add a slightly oily texture to the beer. Other adjuncts like rice or corn server to lighten the character of the beer as well and can also influence the mouthfeel. Another method of controlling the perception of mouthfeel is the original gravity, but only insofar as this effects the final gravity of the brew.

Finally, the use of techniques like protein rests can influence the mouthfeel of the beer. Generally well-modified malts do not require protein rests, and most references seem to agree that commercially available malts are all well-modified in modern times. Some authors have suggested that conducting protein rests on these types of malts can be detrimental to body and mouthfeel in beers, leading to thinner beers with less body.

ENGLISH-STYLE BARLEYWINE (OG: 1.080-1.120+ FG: 1.020-1.030+ IBUs: 50-100 SRM: 10-22) is a very rich and strong ale and has a moderate to intense fruity aroma with a mild to assertive English hop character. Some caramellike aroma is often present. The color is rich gold to very dark amber or even brown. The beer is fruity, with intense malt and balanced to firm hop bitterness. Some oxidative flavors may be present, and alcohol should be evident. The body is full with a slick, viscous texture and gentle smooth warmth from alcohol. Commercial examples include Anchor Old Foghorn, Young’s Old Nick.

AMERICAN-STYLE BARLEYWINE (OG: 1.080-1.120+ FG: 1.020-1.030+ IBUs: 50-100 SRM:10-22 ) is a well-hopped American interpretation of English barleywine and thus has moderate to intense fruitiness with American hop notes and a caramel aroma. The color is rich gold to very dark amber or brown and may have low head retention. The beer is fruity, with intense malt and balanced to firm hop bitterness. Some oxidative flavors may be present, and alcohol should be evident. The body is full with a slick, viscous texture and gentle smooth warmth from alcohol. Commercial examples include Sierra Nevada Bigfoot, Rogue Old Crustacean.

RUSSIAN IMPERIAL STOUT (OG: 1.075-1.095+ FG: 1.018-1.030+ IBUs: 50-90+ SRM: 20-40) is an intense beer with roasty,, fruity, and bittersweet notes and a notable alcohol presence. The aroma features fruity esters, like raisin / plum and intense roastiness. Hop aroma is usually also present. The beer has very dark reddish-black color. The flavor is intensely fruity and malty with balancing roastiness and prominent hop bitterness / flavor. There may be a suggestion of cocoa or strong coffee. The alcohol strength should be evident with complex malt flavor. The finish varies from dry to sweet, with some lingering roastiness and warming character. The body is very full and rich. The carbonation is relatively low. Examples include Samuel Smith Imperial Stout and Rogue Imperial Stout.

All these beers have English origins although the American Barley Wine is an adaptation of the English Barley Wine. In many ways the barleywines are like pale ales on steroids and the imperial stout is a stout on steroids. The key difference between American and English barley wine is the hops used and hop emphasis; American BW uses American hops and tends to have higher flavor and aroma hop profile while the English BW is more restrained and uses English hops. The RIS is a big beer as well but it features roasted malt in addition to robust pale ale malt and intense hoppiness. All the beers are big, and all are fruity in their aroma and flavors.

OLD ALE (OG: 1.060-1.090+ FG: 1.015-1.022+ IBUs: 30-60 SRM: 12-16) is an ale of significant strength though not as strong as barley wines and tilted toward a sweeter, maltier balance. The aroma is malty with complex fruity esters and may have oxidation notes as well that are like port or sherry. The beer is amber to very dark red-amber and the flavor is malty and sweet with fruity esters. The finish can be dry to somewhat sweet and some oxidative notes may be present that are sherry-like. Alcoholic strength should be evident but not overwhelming. The body is medium to full with some alcohol warming notes. Adjuncts may be utilized (sugar or molasses) in small quantities. The hop variety is unimportant as the aging can negate much of its character. Examples include Theakston Old Peculier, Young's Winter Warmer, Marston Owd Roger.

ENGLISH-STYLE BARLEYWINE (OG: 1.080- 1.120+ FG: 1.020-1.030+ IBUs: 50-100 SRM: 10- 22) is a very rich and strong ale and has a moderate to intense fruity aroma with a mild to assertive English hop character. Some caramel like aroma is often present. The color is rich gold to very dark amber or even brown. The beer is fruity, with intense malt and balanced to firm hop bitterness. Some oxidative flavors may be present, and alcohol should be evident. The body is full with a slick, viscous texture and gentle smooth warmth from alcohol. Commercial examples include Anchor Old Foghorn, Young’s Old Nick.

AMERICAN-STYLE BARLEYWINE (OG: 1.080- 1.120+ FG: 1.020-1.030+ IBUs: 50-100 SRM: 10-22 ) is a well-hopped American interpretation of English barleywine and thus has moderate to intense fruitiness with American hop notes and a caramel aroma. The color is rich gold to very dark amber or brown and may have low head retention. The beer is fruity, with intense malt and balanced to firm hop bitterness. Some oxidative flavors may be present, and alcohol should be evident. The body is full with a slick, viscous texture and gentle smooth warmth from alcohol. Commercial examples include Sierra Nevada Bigfoot, Rogue Old Crustacean.

All these beers have English origins although the American Barley Wine is an adaptation of the English Barley Wine. In many ways the barleywines are like pale ales on steroids and the old ale is a less strong, sweeter cousin. The key difference between American and English barley wine is the hops used and hop emphasis; American BW uses American hops and tends to have higher flavor and aroma hop profile while the English BW is more restrained and uses English hops. The Old Ale is also a big beer as well but it features lower gravities and its balance is more toward sweetness and maltiness with lower hopping rates. There is even some overlap in their OG, stylistically defined, but the old ale is a much less hopped beer. All the beers are big, and all are fruity in their aroma and flavors.

Saccharomyces cerevisiae (top-fermenting yeast, or ale yeast) and Saccharomyces uvarum (bottom fermenting yeast or lager yeast). Since “Saccharomyces” is so long, often it is abbreviated with simply an “S” as in “S. uvarum”. S. uvarum and S. Carlsbergensis are two names for the same yeast. Saccharomyces literally means “sugar fungus”. Although generally ale yeast is regarded as “top fermenting”, meaning it stays on the top of the surface of the wort, and lager yeast is “bottom fermenting”, meaning it settles down to the bottom of the vessel to have its feast, many ale strains of yeast actually are bottom fermenters as well.

The two types of yeast differ mainly in their optimum fermentation temperature. Other differences include the ability to ferment different types of sugars, flocculation characteristics (ability to settle out of solution and stop floating around the wort), and production of fermentation byproducts.

Ale yeast ferments best from 55-75 F. They can fully ferment the sugars glucose, fructose, maltose, sucrose, maltotriose, and partially ferment raffinose. Ale yeasts produce esters (fruity-smelling and tasting compounds) because of the higher temperatures they need to stay active. Ale styles include British styles, German alts, kolsch and weizens and Belgian beers. The yeast characteristics that are imparted can lead one to describe these beers as “complex”.

Lager yeasts work best between 46 and 56 F although the California Common strain works well at higher temperatures (58-68 F). In addition to the sugars that ale yeasts ferment, lager strains also ferment raffinose completely. Lager styles are German or Czech in origin, such as pilsners, bocks, helles, dunkels, and octoberfests. The yeast characteristics – or, really, the LACK of yeast characters - that are imparted by lager strains can lead one to describe these beers as “clean”, in that the character of the beer is solely from the water, hops and grains used. We should note that much of this “clean” flavor is also derived from the extended storage of lager beers (lager means “to store”) at near-freezing temperatures prior to serving.

In the brewing process itself, homebrewers are encouraged to practice adequate pitching rates for both types of strains. Suggested rates are 6 to 40 million cells per milliliter. For homebrewers, it is generally recommended to pitch starters consisting of 1/10 the final volume for ale yeast and 1/5 for lager yeast (i.e., ½ gallon for a 5 gallon batch of ale and 1 gallon for a batch of lager). Ale yeasts should be pitched when the beer is at fermentation temperature. For lager yeasts, there are two choices. The first is to add the yeast while the beer is at room temperature, then after fermentation is evident, lower the temperature by 10 degrees every 12 hours. Ester production is minimized because most esters are produced after the first 12 hours. The second method is to pitch the yeast at the fermentation temperature, which can cause a longer lag time but ensures no esters are produced at all.

There are five main places in the brewing process where the water characteristics are most important:

Q18: T14. Explain how the following grains are produced, and what effect each has on beer:

1. Black Patent
2. Chocolate malt
3. Dextrin malt
4. Roasted barley
5. Munich malt

All these grains, except roasted barley, originate as malted barley. Malting is the process where barley kernels are moistened and placed in warm environments to encourage sprouting. After they have sprouted for a while, the growth is suspended by heating. The amount of growth is proportional to “modification”, which refers to the alteration of the kernel by releasing enzymes used in the later conversion of starch to sugar by mashing, as well as the “freeing” of the starch in the kernel for the mashing.

1. Black Patent malt is kilned at very high temperatures to produce a very dark, black kernel. The malt does not require mashing and adds bitter, sharp flavors as well as very dark color and burnt aromas. Different maltsters’ black patent malt is rather variable as far as the degree of these characteristics. Black patent is regarded as a key ingrediant in most porters (though not all).
2. Chocolate malt is allowed to saccharify some then is kilned at high temperatures as well but not as high as black patent malt (nor as long). As a result it is dark brown rather than black and is milder than black patent, lending roasty flavors and aromas, with some burnt caramel and sweetness notes, and can also tend to lend some chocolate type flavors and aromas.
3. Dextrin malt is also known as cara-pils and is made by kilning damp malt at relatively high temperatures to convert starches to sugars, like crystal malt; but unlike crystal malt, it is then dried without allowing the sugars to caramelize or crystallize. The malt contributes little color, but enhances the mouthfeel and perceived body of the beer. The malt has no diastic power, but it must be mashed otherwise it will contribute unconverted starch.
4. Roasted Barley is actually UNMALTED barley that has undergone processing similar to black patent malt. This grain is more coffee-like and less sharp / burnt than the black patent malt, and is a key ingredient in stouts.
5. Munich malt is malted barley that is kilned at temperatures higher than regular pale malts (like Pilsner or pale ale malt), but not nearly as high as the roasted malts listed above. They are kilned at various different temperatures to produce different levels of color in the beer. The higher kilning temperatures also produces more intense malt flavors; as such they are key ingredients in dark German beers like Octoberfests, Bocks and Schwarzbier. The kilning tends to reduce their diastatic power, which is a measure of the enzymes the malt contains that allow the conversion of starches to sugars, but they are still plenty strong to convert themselves. However, they must be mashed and cannot be steeped in extract batches.