16.2.1 Beer

Consumer beer tastes have altered markedly in recent years and today there is a myriad of naturally ‘flavoured’ beers that utilise aroma–contributing materials other than the four traditional raw ingredients: water, cereal, hops and yeast.

Once malt has been ‘mashed’ in hot water (liquor) to convert the starch into fermentable sugars in the brewery to produce ‘wort’, it is boiled and a source of hops is added. This boiling stage is a critical aspect in beer production since bittering substances (resins) and aroma compounds (essential oils) are extracted from the hop flower or cone – originating from the female hop plant (Humulus lupulus). Although hops were cultivated in Babylon as far back as AD 200, there is no record of their use to make beer until around 1079 and their value as a raw material for reasons of flavour and preservation of alcoholic beverages was not recognised until the twelfth century (Moir 2000). To meet the demands of the beer brewing industry, hops are grown widely throughout the world. The success of this perennial climbing plant is that it thrives in temperate climates; therefore large yields are produced annually by Germany, US, Russian Federation, Czech Republic, UK, Slovenia and Poland (McKay et al. 2011a).

Extractable hop resins and oils consist of numerous terpenoid or norisoprenoid natural components (Fig. 16.1). The phenolic norisoprenoids, commonly known collectively as α-acids and β-acids (sometimes referred to as just ‘alpha’), are the principle source ofbitterness whereas monoterpene and sesquiterpene hydrocarbons and their oxygenated derivatives provide the main source of aroma (Fig. 16.1). Fig. 16.1. Some bittering and aroma constituents of hops, with kind permission of John Wiley and Sons Ltd, Chichester, UK. From McKay et al. (2011b)

Table 16.1 details typical α-acid and β-acid compositions alongside typical aroma description, aroma compound composition and flavour intensity for many internationally harvested hop varieties. Cohumulone is commonly regarded as the most aggressive bittering compound of the three main a-acids (Fig. 16.1). This is especially the case when the addition of hops takes place towards the end of the boil (‘late hopping’ – the technique of adding hops to the ‘copper’ or kettle/boiler in the last 5–10 minutes of the boil). Table 16.1. Bittering and aroma compounds of hops Variety Origin α-Acid α/β ratio Cohumulone (% α-acid) Essential oil composition (%) Aroma (flavour intensity * ) Myrcene Carophyllene Farnesene Humulene Selinene Admiral UK 13–16 2.9 37–45 – – – – – Pleasant hoppy character (8) Ahtanum USA 5.7–6.3 1.1 30–35 50–55 9–12 – 16–20 – Distinctive unusual floral aroma (7) Bramling Cross UK 5–7 2.2 34 36.54 15.72 0.21 30.57 4.02 Distinctive spicy/goldcurrant (7) Brewers Gold Germany 5–9 – 40–48 38.5 7.3 – 30 1.8 Fruity spicy character (8) Cascade USA 4–7 0.9 33–40 45–60 3–6 4–8 10–16 – Very floral and spicy (9) Centennial USA 6–11 – 29–30 45–55 5–8 < 1 10–18 – Floral qualities with delicate citrus (7) Challenger UK 5–9 2.0 20–25 30.49 9.52 1.73 29.52 12.87 Fruity strawlike (6) Chinook USA 10–15 – 29–34 35–40 9–11 < 1 20–25 – Very strong grapefruit character (8) Cluster USA 6–9 – 36–42 45–55 6–7 < 1 15–18 – Deep fruit hop (6) Columbus (Tomahawk) USA 14–17 – – – – – – – Citrus sherbet aroma if used late (8) Crystal USA 4–6 0.8 20–22 40–65 4–8 0.1 18–24 – Aroma hop with hints of tangerine (4) First Gold UK 6–10 2.1 33 – – – – – Slightly spicy and orangy/citrus notes (6) Fuggle UK 3–6 1.8 33 25.04 13.38 5.72 38.47 2.43 Delicate, minty, grassy, slightly floral (4) Galena USA 12–14 1.7 32–42 55–60 3–5 > 1 10–15 – Blackcurrant strong fruity Golding UK 4–7 2.3 28 24.91 14.75 0.41 45.26 2.59 Traditional, smooth almost sweet delicate slightly spicy (4) Green Bullet New Zealand 11–15 1.8 41.3 52.2 6.4 – 19.5 0.144 Styrian type pine lemon excellent aroma (8) Hallertauer Aroma New Zealand 7–11 1.2 35.2 47.27 6.24 5.06 12.45 1.841 Bred from Mittlefruh, floral, vanilla (4) Hallertauer (Mittlefrüh) Germany 4.6 1 – 15.5 14.6 0.1 55.1 1.5 Delicate aroma for lager or lighter cask ales (3) Hallertauer Hersbrucker Germany 2–5 – – 12.7 13.6 – 32.4 12.8 Delicate aroma for lager or lighter cask ales (4) Horizon USA 10–16.5 1.6 17–22 65–70 5–6 2 8–10 – Aromatic Liberty USA 3–6 – 24–28 32–42 9–12 < 1 30–40 55–60 Spicy with hint of lemon/citrus (5) Mount Hood USA 3–6 – 22–23 55–65 7–10 < 1 15–25 50–60 Floral and slightly herbal (6) Northdown UK 6–10 1.6 24–29 26–36 15 1.1 43 2 Challenger type aroma but richer flavour (6) Northern Brewer Germany 6–10 – 28–31 36.4 12.4 0.1 30.7 1.6 Similar to Northdown, pleasant aroma (5) Nugget USA 11–15 – 24–30 51–59 7–10 < 1 12–22 – Resinous hoppy aroma (6) Pacific Gem New Zealand 13–18 1.7 38.5 55.35 6.56 0.048 17.97 0.198 Distinctive berryfruit (5) Pacific Hallertau New Zealand 3–6 1 25.8 32.08 12.89 0.059 36.24 0.358 From Mittlefrüh, classic aroma (5) Perle Germany 6–10 – 28–32 23 9.1 0 35 0.6 Light lager hop with fruit (5) Phoenix UK 8–12 2.1 30 – – – – – Very mellow (3) Pilgrim UK 9–13 2.4 36–38 36 7.3 0.3 16.9 8.6 Unusual pleasant lemon/grapefruit distinctively hoppy (6) Pioneer UK 7–11 2.4 37 – – – – – Unusual pleasant lemon/grapefruit distinctively hoppy (8) Progress UK 4–7 2.3 28 – – – – – Slightly sweeter alternative to Fuggle (4) Target UK 8–13 2.2 37 – – – – – Slightly harsh (8) Saaz Czech Rep. 2–5 0.5 26 42 6 15 19 0.53 Delicate, earthy lager hop (4) Santiam USA 5.5–7 – 20–22 30–45 5–8 13–16 20–25 – Delicate lager hop aroma (4) Spalt Select Germany 3.5–5.5 1.0 25.8 32.08 12.89 0.059 36.24 0.358 Classic lager aroma (5) Styrian Goldings Slovenia 3–6 1:5 27–33 25–38 9–12 6–8 29–38 – Distinctive perfume pine/lemon/citrus hop (9) W.G.V UK 5–8 2.8 34 26 13 2 41–48 3 Similar to Golding (4) Williamette USA 3–6 – 30–35 45–55 7–8 5–6 20–30 – Estery blackcurrant and herbal (6) Source: www.wellhopped.co.uk/Variety%20Brochure.pdf (Charles Faram and Co. Limited) and www.wellhopped.co.uk/Variety.asp (Charles Faram and Co. Limited).

Hop varieties can generally be divided into categories according to their α-acid content. Low (~5%) α-acid varieties (often referred to as aroma or noble varieties) include Cascade (US), Crystal (US), Goldings (UK), Fuggles (UK), Hallertau (Germany), Liberty (US), Mount Hood (US), Saaz (Czech Republic, Germany) and Styrian Goldings (Slovenia). Moderate to high α-acid (8–15%) varieties (commonly known as bittering hops) include Admiral (UK), Columbus (US), Galena (US), Nugget (US), Pacific Gem (New Zealand), Phoenix (UK), Pilgrim (UK), Pioneer (UK) and Target (UK). Other varieties are considered ‘dual purpose’ in that they can be used to both bitter beer and add characteristic aroma. Examples include Challenger (UK), Chinook (US), First Gold (UK), Green Bullet (New Zealand), Northdown (UK), Northern Brewer (Germany, UK) and Perle (Germany).

Myrcene is one of the most significant and pungent of the aroma compounds whereas humulene is much more subtle, but each compound will make its own contribution and together they will play a major role in the aroma profile of a particular hop variety. The contribution of hop aroma to beer beverages has been extensively studied in the literature. For example, Lermusieau et al. (2001) used aroma extract dilution analysis (AEDA) to compare the beer aromas derived from Challenger and Saaz hop pellets. State-of-the-art analytical techniques have also been used more recently to: • Study the decrease and increase of several key hop derived terpenoids during boiling (Kishimoto et al. 2005). • Study the odour-active compounds in the spicy fraction of hop essential oil from four different varieties (Eyres et al. 2007). • Compare odour-active compounds in unhopped wort and beers hopped with different hop varieties (Kishimoto et al. 2006). • Identify and characterise new volatile thiols derived from hops (Takoi et al. 2009) (Fig. 16.2). Fig. 16.2. Odorous thiols found in Nelson Sauvin (New Zealand) hops. *New. From Takoi et al. (2009)

During the harsh boiling and subsequent fermentation stages of beer production, large quantities of aroma compounds are lost through evaporation and by numerous chemical transformations. However, brewery controls using a particular hop variety should ensure that the hop character of the finished beer remains reasonably constant from batch to batch.

Many beers are produced using a single traditional hop variety, but others are brewed with two or more varieties, often for a particular aroma/flavour impact character. It is quite common for high α-acid hops to be added at the start of boiling, with aroma hops being added toward the end of boiling and post boiling, or for aroma hop and dual purpose hops to be added at the start and toward the end of the boiling. The brewery’s aim is to achieve an acceptable bitterness and to preserve the attractive aroma. This aim can also be fulfilled by the use of isomerised hop products/extracts (see Table 16.2) and by the dry hopping (a common term used to describe the addition of several hop cones to the cask after filling to supply fresh hop aroma but no extra bitterness) of cask-conditioned beers. Table 16.2. Hop products and point of use Brew kettle Post fermentation Non-isomerised: Whole hops Hop pellets 1 Stabilised hop pellets 2 Isomerised hop extracts: iso-α-acids 7 Liquid and supercritical CO 2 extracts 3 Reduced isomerised hop extracts: Ethanol extract 4 Dihydro-(Rho)-iso-α-acids 8 Isomerised hop products: Tetrahydroiso-α-acids 9 Isomerised hop pellets 5 Hexahydrosio-α-acids 10 Isomerised kettle whole hop extract 6 Pure hop oil/oil rich (CO 2 ) extracts/emulsions 11 Isomerised hop extracts: iso-α-acids 7 Soluble hop aromas 12 Reduced isomerised hop extracts: Dihydro-(ρ)-iso-α-acids 8 Notes:

Following harvesting, hops are dried and compressed often in sacks and bales for large quantities, or double silver foil vacuum packs for smaller requirements. Breweries generally purchase pack sizes as close to the brew length usage as possible and purchase the latest harvest hops, which are stored religiously in a deep freeze, refrigerator or cold room (Bruning 2009). Unfortunately the compression packing techniques rupture many of the lupulin glands in the hop cones, and oxidative degradations and other transformations occur during extended storage periods. Loss of α-acids, in particular, can be extensive (~50%) after 12 months storage, even at low temperatures. In extreme cases, the carbonyl side chains of a-acids (Fig. 16.1) are oxidised to short chain carboxylic acids, which have distinctive cheesy notes. Because of this, some breweries use hop powders, pellets or extracts to supplement, or to replace entirely, hop cones in the kettle as pellets do not deteriorate as rapidly as cones (especially if stored at 0–5 °C) and offer a higher degree of a-acid extraction/isomerisation. Table 16.2 lists the main hop products and their point of use available to the commercial brewer.

Certain hop pellets are made from mechanically enriched powder and are especially useful for the dry hopping of cask-conditioned ales. Stabilised hop pellets are prepared by mixing 1–2% (w:w) of magnesium or calcium oxide with hop powder to convert the α-acids into more stable salts (Briggs et al. 2004; McKay et al. 2011a).

A majority of modern hop extracts are produced using liquid and supercritical carbon dioxide (CO 2 ) (at ca. 10 °C and 50 atm. pressure) since this allows collection of multiple hop fractions (aroma compounds (essential oil), β-acids, α-acids). Hop oil, produced by the low pressure (~0.02 mm Hg) steam distillation of hop powder at 25 °C can be added either to bright beer during conditioning or used for the dry hopping of cask–conditioned beers.

During the boiling process of beer production, many of the aroma (essential oil) and resinous components are either lost to the atmosphere, decompose or rearrange (as with the acid-catalysed reactions of citrus oil components, terpenoids of hop are particularly prone to rearrangement when heated under mild acidic conditions (Clark and Chamblee 1992)).

The conversion of α-acids to the vastly more hydrophilic iso-α-acids (by a ring contracting rearrangement) is the principle isomerisation (see Fig. 16.3 for the example of humulone to isohumulone) alongside, for example, various hydrolysis and oxidation reactions (McKay et al. 2011a). Many of these conversions are incomplete after traditional brewery boiling times (60–120 minutes), particularly with regard to iso-a-acid formation, and hence isomerised hop extracts are often added to post fermented beer (see Table 16.2). This allows the control of consistent bitterness (expressed as international bittering units (IBU)), which is commercially important for larger breweries with multiple production sites and global markets. Fig. 16.3. Isomerization of humulone during boiling of hopped wort, with kind permission of John Wiley and Sons Ltd, Chichester, UK. From McKay et al. (2011b)

Some beers are flavoured at breweries with ingredients other than or as well as hops. This flavouring addition occasionally takes place at the boiling stage, but is usually carried out during the fermentation or conditioning/maturation stages. Some examples of naturally flavoured beers using ingredients including whole fruits (or concentrates), beans and pods, spices, leaves, needles and oak are shown in Table 16.3. Table 16.3. Examples of flavoured beers using ingredients other than or as well as hops Brand (brewery) Origin % ABV Natural flavouring ingredient(s) Alaskan Winter Ale (Alaskan Brewing Co.) USA 6.4 Sitka spruce tips Apple (Lindemans) Belgium 3.5 Apple Banana Bread Beer (Wells & Young’s) UK 5.2 Fairtrade bananas Cassis (Lindemans) Belgium 3.5 Blackcurrants Celebrate Chocolate & Cherry (Anheuser-Busch) USA 8.5 Natural cherry juice and matured on dark sweet cherries and cocoa beans Cuvée-Brut (Liefmans) Belgium 6.0 Old brown beer (100 litres) macerated with fresh whole cherries (13 kg) and matured for 12 months before blending with beer of different ages Double Chocolate Stout (Wells & Young’s) UK 5.2 Real dark chocolate and chocolate essence Framboise (Lindemans) Belgium 2.5 Lambic beer blended with raspberries Fraoich (Williams Brothers Brewing Co.) UK 5.0 Sweet gale (myrica gale or bog myrtle) and flowering heather during boil. After cooling poured into vat of fresh heather flowers and infused for an hour Febbre Alta (Birrificio Troll) Italy 8.7 Sixteen different aromatic herbs Fruitesse (Liefmans) Belgium 4.2 Beer matured for 18 months on cherries which is blended with juices of cherry, bilberry, elderberry, strawberry and raspberry Harvest Pumpkin Ale (Blue Moon/Coors Brewing Co.) USA 5.8 Vine ripened pumpkin, allspice, cloves and nutmeg Hazelnut Brown Nectar (Rogue Brewery Co.) USA 6.2 Hazelnut extract Hoegaarden (Anheuser–Busch In Bev) Belgium 4.9 Coriander seeds, curacao orange peel Innis & Gunn IPA (Belhaven/Greene King) UK 6.4 Matured in new oak casks for one month Juniper Pale Ale (Rogue Brewery Co.) USA 5.2 Infused with whole juniper berries Kriek (Lindemans) Belgium 3.5 Lambic beer (six months old) matured for 8–12 months on cherries La Dragonne (Brasserie des Franches–Montagnes) Switzerland 7.0 Honey and spices Oatmeal Stout (Samuel Smith’s) UK 5.0 Oatmeal Organic Honey Dew (Fuller’s) UK 5.0 Organic honey Original Smokebeer “Rauchbier” (Schlenkerla) Germany 5.1 Smoky bacon like flavour is achieved by exposing the malt to the intense, aromatic smoke of burning beech-wood logs at the Schlenkerla maltings. After mixing it with premium-class hops in the brew, it matures in 700–year–old cellars Oyster stout (Porterhouse Brewing Co.) Ireland 4.8 Fresh oyster Palanfrina (Birrificio Troll) Italy 9.0 Chestnuts Pecheresse (Lindemans) Belgium 2.5 Peach juice Rose Petal Imperial Golden Ale (Caldera Brewing Company) USA 6.7 Brewed with real rose petals and Bulgarian rose water Shangrila Ale (Birrificio Troll) Italy 8.5 Mixture of spices from the Himalayas: tandoori (blend of coriander, cumin, garlic powder, paprika, ginger, cardamom, saffron), curry, pepper, anise Spruce Goose (Steamworks Brewing Co.) USA 8.1 Spruce pine Tokyo (Brewdog) UK 18.2 Jasmine and cranberries then aged on oak chips Umbel Ale (Nethergate) UK 3.8 Coriander seed Waggle Dance (Wells & Young’s) UK 4.0 Fair trade South American honey Winter’s Bourbon Cask Ale (Anheuser–Busch In Bev) USA 6.0 Aged in new bourbon casks over whole vanilla beans

Adjuncts are used in brewing beer to supplement the main ingredients in the mash (malted barley). The intention of adjunct addition can be to lower the overall raw material costs (provide a cheaper source of carbohydrate) or to modify the flavour and/or colour or to provide a direct function (such as foam retention). These important materials can be broadly separated into solids and liquid syrups. Typical solid adjuncts are unmalted grains such as corn, rice, rye, oats, barley (a variety of flavours and colours can be provided depending on the kilning temperatures and the humidity and duration of heating), and wheat whereas liquid adjuncts include malt extracts and sugar syrups added at the boiling stage of production (often referred to as brew length or wort extenders). Common solid beer adjuncts alongside their reasons for use and typical usage concentrations are shown in Table 16.4. The degree of malt colouration can be estimated by visible spectrophotometry or colorimetry, and is expressed on scales devised by the American Society of Brewing Chemists (Standard Research Method, SRM, similar to the old Lovibond scale) or the European Brewing Convention (EBC). Table 16.4. Common beer adjuncts Adjunct Origin Reason for use 1 , 2 Typical concentration Acid Malt Germany Adjunct for producing high class lagers. Contains lactic acid, which lowers the mash pH giving a softer palate than if gypsum is used for water (liquor) treatment. The inclusion of a small percentage of this malt is recommended for all pale lagers. Colour EBC 3 (SRM 1.6) Up to 10% of grist Amber Malt UK A traditional but rare malt for dry biscuit finishes to bitters and pale milds and outstanding in dark ales, especially porters. Colour EBC 50–90 (SRM 20–35) Up to 20% of grist Amber Malt Diastatic Belgium Roasted at a lower temperature to preserve the diastatic enzymes. Indispensable for recreating historic English beers. Colour EBC 50–60 (SRM 20–24) Up to 80% of grist Aromatic Malt Belgium Aromatic malt provides a very strong malt flavour and aroma. Colour EBC 150–160 (SRM 58–62) Up to 20% of grist Barley Flaked UK Imparts a grainy flavour and can be used in quite large quantities in black beers. Can cause haze problems in paler styles where the percentage should not exceed 5%. Colour EBC 3 (SRM 1.6) Up to 20% of grist Barley Roasted UK Raw barley roasted as far as possible to make the darkest of all grains. Slightly bitter burnt taste finds favour in Irish type stouts and used sparingly to darken other beers. Sharp dry bitter flavour. Colour EBC 1220 (SRM 470) Up to 10% of grist Biscuit Malt Belgium Provides a sweet, biscuit aroma to beer. Colour EBC 50 (SRM 20) Up to 15% of grist Black Malt UK Produced by roasting British pale malt as far as possible without burning. It is the preferred darkener in sweeter stouts and porters and can be used for minor colour adjustments in other beers Strong burnt coffee flavour. Colour EBC 1100 (SRM 424) Up to 10% of grist Brown Malt UK Although wood smoked this malt can be used in old recipes calling for brown malt, especially if used with a proportion of Rauchmalz. Brown malt can also add complexity to styles such as porter and old ale. Colour EBC 140–160 (SRM 54–62) Up to 20% of grist Cara Amber Germany Improves flavour stability and promotes fuller body. Provides deep red colour. An interesting addition for all amber and dark beers. Colour EBC 60–80 (SRM 24–31) Up to 20% of grist Carafa Special 1 Germany Greatly reduces the harshness usually associated with highly roasted grains, while retaining the required colour, aroma and body. Used for dark lagers and as an alternative to chocolate malt in all beers. Colour EBC 800 (SRM 308) Up to 5% of grist Carafa Special 3 Germany Greatly reduces the harshness usually associated with highly roasted grains, while retaining the required colour, aroma and body. Used for dark lagers and as an alternative to chocolate malt in all beers. Colour EBC 1200 (SRM 462) Up to 5% of grist Carahell Germany Mainly used to accentuate the fullness of flavour in special German festival beers. Greatly increases head formation and retention Up to 40% of grist Caramalt UK Used when a crystal character is required without unduly darkening the beer. Particularly suitable for pale ales and bitters. Colour EBC 30–40 (SRM 12–16) Up to 20% of grist Caramünch Germany Only used in small quantities but has a marked effect on the fullness of flavour and aroma in golden to brown lager beers and ales. Colour EBC 80–100 (SRM 31–39) Up to 10% of grist Carapils Malt Germany Promotes head formation and retention and gives the beer a fuller rounder flavour Up to 10% of grist Cara Red Germany Adds body and increases malt aroma in many beer styles. Provides greater depth of colour and a reddish hue. Colour EBC 40–60 (SRM 16–24) Up to 10% of grist Chocolate Malt Pale UK When used in small quantities will impart a rich chocolate flavour to such beers as brown ales and porters. Colour EBC 600 (SRM 231) Up to 5% of grist Chocolate Malt Standard UK When used in small quantities will impart a rich chocolate flavour to such beers as brown ales and porters. Colour EBC 800 (SRM 308) Up to 5% of grist Crystal Malt Light UK Increasing body and fullness while preserving a pale colour. Unsurpassed in bitter beers and pale ales for adding subtle sweetness to balance the customary high hop rate. Colour EBC 60–80 (SRM 24–31) Up to 20% of grist Crystal Malt Standard UK Unsurpassed in bitter beers for adding subtle sweetness to balance the customary high hop rate. Colour EBC 80–140 (SRM 31–54) Up to 20% of grist Crystal Malt Dark UK Very dark crystal malt which has undergone a substantially extended kilning. Used in beers that require a deep copper colour without too much crystal character, or in porter and old ale. Colour EBC 250–300 (SRM 97–116) Up to 10% of grist Crystal Malt Extra Dark UK Colour EBC 400 (SRM 154) Up to 10% of grist Maize Flaked UK Gives a delicate corn taste to beer if used sparingly. Beneficial for clearing purposes due to its low nitrogen content. Colour EBC 3 (SRM 1.6) Up to 10% of grist Melanoidin Malt Germany Promotes fullness of flavour and rounds off beer colour. It can be used to good effect in all medium to dark beers, especially Munich style lagers. Colour EBC 60–80 (SRM 24–31) Up to 15% of grist Munich Malt Germany/Belgium Dry, aromatic and flavourful. Colour EBC 15–25 (SRM 6–10) Up to 20% of grist (ales) Oat Malt UK Enhances body and flavour of stouts, porters and winter warmers. Colour EBC 2 (SRM 1.2) Up to 5% of grist Rice Flaked USA Substitute for any recipe calling for the addition of sugar. It is virtually flavourless but provides some body without darkening the colour. Low nitrogen content assists in clearing. Up to 25% of grist Rye Malt Crystal UK Strongly flavoured and distinctive. Colour EBC 100–120 (SRM 39–47) Up to 10% of grist Rye Malt Pale UK Used alongside crystal and roasted rye malts to brew the classic German top–fermented quantities to add interesting flavours to other ales. Colour EBC 4–6 (SRM 2–3) Up to 50% of grist Rye Malt Roasted UK Can be used in conjunction with pale rye and wheat malt to make Bavarian Roggenbier or used to increase the complexity of flavour in many other top fermenting styles. Colour EBC 800 (SRM 308) Up to 3% of grist Special B Belgium Profile is that of a cross between dark caramel malt and medium roasted malt. Colour EBC 250–300 (SRM 97–116) Up to 10% of grist Wheat Malt Chocolate UK Roasted to a very high colour, this is only used for top fermented ales such as alt and dark wheat beers. Even in very small quantities intensifies the beer aroma and colour. Colour EBC 800 (SRM 308) Up to 2% of grist Wheat Malt Crystal UK In effect crystal malt made from wheat. Can be used in all German style top fermenting beers to increase the fullness of body and intensify the wheat malt aroma. Colour EBC 100–120 (SRM 39–47) Up to 15% of grist Wheat Malt Dark Germany Not particularly dark in colour. Only produced in Germany and is used for Weizen, Kölsch, Alt and some other top fermented beers. Colour EBC 15–17 (SRM 6–7) Up to 70% of grist Wheat Malt Pale UK Used to enhance roundness of flavour and head formation in most beer styles. Colour EBC 3–4 (SRM 1.6–2) Up to 70% of grist Wheat Torrefied UK Used to aid head retention and gives a slightly nutty/biscuit flavour. Colour EBC 2.75 (SRM 1.5) Up to 10% of grist Notes:

The only allowed colorant for addition to beer is caramel (E150). This enables the brewery to carry out colour adjustments for darker beers. The E150 variants also find use as a colorant in other popular alcoholic beverages (see Table 16.11 for further information).

Finally, although not discussed here, the importance of water (liquor) chemistry cannot be overestimated for the brewing of high quality beer. This is achieved in simplistic terms by the removal of unwanted ions and the addition of required levels of desirable ions – calcium being the most important (www.murphyandson.co.uk/BrewingArticles/WaterEverywhere.htm).