On Food And Cooking Part 91

South America and elsewhere South America and elsewhere

Boiled manioc root, chewed to contribute saliva enzymes Boiled manioc root, chewed to contribute saliva enzymes

Millet, sorghum, rice beers

Africa, Asia Africa, Asia

Millet, sorghum, rice Millet, sorghum, rice

Boza/bouza

Southwest Asia, North Africa Southwest Asia, North Africa

Bread made from malted millet, wheat Bread made from malted millet, wheat

Pombe ya ndizi

Kenya Kenya

Bananas and malted millet Bananas and malted millet

Kva.s.s

Russia Russia

Rye bread Rye bread

Roggenbier

Germany Germany

Malted rye Malted rye

Germany: Hops and Lagering In the centuries following the fall of Rome, beer continued to be an important beverage in much of Europe. Monasteries brewed it for themselves and for nearby settlements. By the 9th century, alehouses had become common in England, with individual keepers brewing their own. Until 1200, the English government considered ale to be a food, and did not tax it. In the centuries following the fall of Rome, beer continued to be an important beverage in much of Europe. Monasteries brewed it for themselves and for nearby settlements. By the 9th century, alehouses had become common in England, with individual keepers brewing their own. Until 1200, the English government considered ale to be a food, and did not tax it.

It was in medieval Germany that two great innovations made beer largely what it is today: brewers preserved and flavored it with hops, and began to ferment it slowly in the cold to make mild-flavored lager. lager.

Hops The earliest brewers probably added herbs and spices to beer, both to give it flavor and to delay the development of off-flavors from oxidation and the growth of spoilage microbes. In early Europe this mixture, called The earliest brewers probably added herbs and spices to beer, both to give it flavor and to delay the development of off-flavors from oxidation and the growth of spoilage microbes. In early Europe this mixture, called gruit gruit in German, included bog-myrtle, rosemary, yarrow, and other herbs. Coriander was also sometimes used, juniper in Norway, and sweet gale ( in German, included bog-myrtle, rosemary, yarrow, and other herbs. Coriander was also sometimes used, juniper in Norway, and sweet gale (Myrica gale) especially in Denmark and Scandinavia. It was around 900 that hops, the resinous cones of the vine Humulus lupulus, Humulus lupulus, a relative of marijuana, came into use in Bavaria. Thanks to its pleasant taste and effectiveness in delaying spoilage, it had largely replaced a relative of marijuana, came into use in Bavaria. Thanks to its pleasant taste and effectiveness in delaying spoilage, it had largely replaced gruit gruit and other herbs by the end of the 14th century. In 1574, Reginald Scot noted in and other herbs by the end of the 14th century. In 1574, Reginald Scot noted in A Perfite Platforme of a Hoppe Garden A Perfite Platforme of a Hoppe Garden that the advantages of hops were overwhelming: "If your ale may endure a fortnight, your beer through the benefit of the hops, shall continue a month, and what grace it yieldeth to the taste, all men may judge that have sense in their mouths." Still, it was not until about 1700 that English ale was hopped as a matter of course. that the advantages of hops were overwhelming: "If your ale may endure a fortnight, your beer through the benefit of the hops, shall continue a month, and what grace it yieldeth to the taste, all men may judge that have sense in their mouths." Still, it was not until about 1700 that English ale was hopped as a matter of course.

Food Words: Malt MaltOur ancestors probably began soaking and sprouting grains because it was an easy way to make them soft enough to eat as is, and quicker to cook. In fact our word for soaked, partly sprouted cereal grain comes from an Indo-European root meaning "soft." Words that are related to malt malt include include melt, mollusc melt, mollusc (p. 226), and (p. 226), and mollify. mollify.

Lager From the times of Egypt and Sumeria to the Middle Ages, brewers made beer without much control over the temperature of fermentation, and with yeasts that grew at the surface of the liquid. The beer fermented in a few days, and it was consumed within days or weeks. Sometime around 1400, in the foothills of the Bavarian Alps, there evolved a new kind of beer. It was fermented in cool caves over the period of a week or more, and with a special yeast that grew below the surface of the liquid. Then it was packed in ice for several months before it was drawn off the yeast sediment for drinking. The cool, slow fermentation gave the beer a distinctive, relatively mild flavor, and the cold temperature and long settling time produced a sparkling-clear appearance. This From the times of Egypt and Sumeria to the Middle Ages, brewers made beer without much control over the temperature of fermentation, and with yeasts that grew at the surface of the liquid. The beer fermented in a few days, and it was consumed within days or weeks. Sometime around 1400, in the foothills of the Bavarian Alps, there evolved a new kind of beer. It was fermented in cool caves over the period of a week or more, and with a special yeast that grew below the surface of the liquid. Then it was packed in ice for several months before it was drawn off the yeast sediment for drinking. The cool, slow fermentation gave the beer a distinctive, relatively mild flavor, and the cold temperature and long settling time produced a sparkling-clear appearance. This lager lager beer (from the German beer (from the German lagern, lagern, "to store," "to lay down") remained distinctly Bavarian until the 1840s, when the special yeast and techniques were taken to Pilsen, Czechoslovakia, to Copenhagen, and to the United States, and became the prototype of most modern beers. England and Belgium are the only major producers that still brew most of their beer in the original way, at warm temperatures and with top-fermenting yeasts. "to store," "to lay down") remained distinctly Bavarian until the 1840s, when the special yeast and techniques were taken to Pilsen, Czechoslovakia, to Copenhagen, and to the United States, and became the prototype of most modern beers. England and Belgium are the only major producers that still brew most of their beer in the original way, at warm temperatures and with top-fermenting yeasts.

England: Bottles and Bubbles, Specialty Malts The English were late to accept hops, but pioneered in the making of bottled beer. Ordinary ale - the original English word for beer - was fermented in an open tank, and like wine it lost all its carbon dioxide to the air: the bubbles simply rose to the surface and burst. Some residual yeast might grow while the liquid was stored in a barrel, but it would lose its light ga.s.siness as soon as the barrel was tapped. Sometime around 1600, it was discovered that ale kept in a corked bottle would become bubbly. Quite early on, the discovery was attributed to Alexander Nowell, dean of St. Paul's Cathedral. Thomas Fuller, in his 1662 The English were late to accept hops, but pioneered in the making of bottled beer. Ordinary ale - the original English word for beer - was fermented in an open tank, and like wine it lost all its carbon dioxide to the air: the bubbles simply rose to the surface and burst. Some residual yeast might grow while the liquid was stored in a barrel, but it would lose its light ga.s.siness as soon as the barrel was tapped. Sometime around 1600, it was discovered that ale kept in a corked bottle would become bubbly. Quite early on, the discovery was attributed to Alexander Nowell, dean of St. Paul's Cathedral. Thomas Fuller, in his 1662 History of the Worthies of England, History of the Worthies of England, wrote: wrote: Without offense it may be remembered, that leaving a bottle of ale, when fis.h.i.+ng, in the gra.s.s, [Nowell] found it some days after, no bottle, but a gun, such the sound at the opening thereof: and this is believed (casualty is mother of more invention than industry) the original of bottled ale in England.

By 1700, gla.s.s-bottled ale sealed with cork and thread had become popular, along with sparkling Champagne (p. 724). But both were largely novelties. Most beer was drunk flat, or close to it, from barrels. Centuries later, with the development of airtight kegs, of carbonation, and the increasing tendency to drink beer at home instead of at the tavern, bubbly beer became the rule.

Specialty Malts The 18th and 19th centuries were an innovative time in Britain, and it was early in this period that many of today's familiar British brewing names - Ba.s.s, Guinness, and others - got their start. By 1750, the greater control that c.o.ke and coal heat gave the maltster made gently dried pale malts possible, and thereby pale ales. And in 1817, "patent malt" was developed. This was malted barley roasted very dark, and used in small amounts only to adjust the color and flavor of ales and beers, not to provide fermentable sugars. Patent and pale malts made it possible to produce a range of dark beers with a combination of light, largely fermentable malt and very dark coloring malt. This was the beginning of porter and stout as we know them today: darker and heavier than ordinary brews, but much lighter and less caloric than they were 200 years ago. The 18th and 19th centuries were an innovative time in Britain, and it was early in this period that many of today's familiar British brewing names - Ba.s.s, Guinness, and others - got their start. By 1750, the greater control that c.o.ke and coal heat gave the maltster made gently dried pale malts possible, and thereby pale ales. And in 1817, "patent malt" was developed. This was malted barley roasted very dark, and used in small amounts only to adjust the color and flavor of ales and beers, not to provide fermentable sugars. Patent and pale malts made it possible to produce a range of dark beers with a combination of light, largely fermentable malt and very dark coloring malt. This was the beginning of porter and stout as we know them today: darker and heavier than ordinary brews, but much lighter and less caloric than they were 200 years ago.

Food Words: Ale Ale and and Beer Beer; Brew BrewThe original English word for a fermented barley drink was not beer, beer, but but ale. ale. It apparently derives from the effects of alcohol; the Indo-European root of It apparently derives from the effects of alcohol; the Indo-European root of ale ale had to do with intoxication, magic, and sorcery, and may be related to a root meaning "to wander, to be in exile." The alternative name, had to do with intoxication, magic, and sorcery, and may be related to a root meaning "to wander, to be in exile." The alternative name, beer, beer, comes via Latin from a much more prosaic connection: its root is the word for "to drink." comes via Latin from a much more prosaic connection: its root is the word for "to drink." Brew Brew is related to is related to bread, broil, braise, bread, broil, braise, and and ferment ferment; they all come from an Indo-European root meaning "to boil, to bubble, to effervesce."

Beer in America The U.S. preference for light, even characterless brews would seem to be the result of climate and history. Heavy beer is less refres.h.i.+ng when the summers get as hot as ours do. And the original British colonists seem to have been more interested in making whiskey than beer (p. 760). We had no strong national tradition in the matter of beer, so the way was clear for later German immigrants to set the taste around 1840, when someone - perhaps one John Wagner near Philadelphia - introduced the newly available lager yeast and technique, and the distinctive brew caught on. The U.S. preference for light, even characterless brews would seem to be the result of climate and history. Heavy beer is less refres.h.i.+ng when the summers get as hot as ours do. And the original British colonists seem to have been more interested in making whiskey than beer (p. 760). We had no strong national tradition in the matter of beer, so the way was clear for later German immigrants to set the taste around 1840, when someone - perhaps one John Wagner near Philadelphia - introduced the newly available lager yeast and technique, and the distinctive brew caught on.

Both Milwaukee and St. Louis quickly became centers of lager brewing: in the former, Pabst, Miller, and Schlitz; in the latter, Anheuser and Busch; and Stroh in Detroit all got their starts in the 1850s and 1860s, and Coors in Denver in the 1870s. Several of these names and their light, Pilsner-style beers remain dominant today, while the stronger traditional brews of England and Germany appeal to a relatively small number of beer lovers. The only indigenous American style of beer is "steam beer," a rare relic of the California Gold Rush. Without the large supply of ice necessary to make lager beer, San Francis...o...b..ewers used the yeast and techniques appropriate to cool bottom fermentation, but brewed at top-fermentation temperatures. The result: a full-flavored and ga.s.sy beer that gave off a lot of foam when the keg was tapped.

Beer Today Today, the countries with the largest per capita consumption of beer are mainly traditional European beer producers: Germany, the Czech Republic, Belgium, and Britain and its former colony Australia. In the United States, beer accounts for more than three quarters of the alcoholic drinks consumed. Most American beer remains bland and uniform, produced by a handful of large companies in largely automated factory-like breweries. The 1970s brought a revival of interest in more flavorful alternatives, and a flouris.h.i.+ng of "microbreweries" making specialty beers in small quant.i.ties, brewpubs that both brew and serve beer, and home brewing. Some of these small enterprises have grown with their success, and the giant brewers are now making microbrew lookalikes. And it's now possible to find beers from all over the world in liquor stores and supermarkets. These are good times for exploring the many different styles of beer and ale. Today, the countries with the largest per capita consumption of beer are mainly traditional European beer producers: Germany, the Czech Republic, Belgium, and Britain and its former colony Australia. In the United States, beer accounts for more than three quarters of the alcoholic drinks consumed. Most American beer remains bland and uniform, produced by a handful of large companies in largely automated factory-like breweries. The 1970s brought a revival of interest in more flavorful alternatives, and a flouris.h.i.+ng of "microbreweries" making specialty beers in small quant.i.ties, brewpubs that both brew and serve beer, and home brewing. Some of these small enterprises have grown with their success, and the giant brewers are now making microbrew lookalikes. And it's now possible to find beers from all over the world in liquor stores and supermarkets. These are good times for exploring the many different styles of beer and ale.

Brewing Ingredients: Malt Beer begins with barley. Other grains - oats, wheat, corn, millet, sorghum - have also been used, but barley has become the grain of choice because it's the best at generating starch-digesting enzymes.

Malting The first step in converting barley grain into malt is to steep the dry grain in cool water and then allow it to germinate for several days at around 65F/18C. The embryo restarts its biochemical machinery and produces various enzymes, including some that break down the barley cell walls, and others that break down the starch and proteins inside the cells of the food-storage tissue, the endosperm. These enzymes then diffuse from the embryo into the endosperm, where they work together to dissolve away the cell walls, penetrate the cells, and digest some of the starch granules and protein bodies inside. The embryo also secretes the hormone gibberellin, which stimulates the aleurone cells to produce digestive enzymes as well. The first step in converting barley grain into malt is to steep the dry grain in cool water and then allow it to germinate for several days at around 65F/18C. The embryo restarts its biochemical machinery and produces various enzymes, including some that break down the barley cell walls, and others that break down the starch and proteins inside the cells of the food-storage tissue, the endosperm. These enzymes then diffuse from the embryo into the endosperm, where they work together to dissolve away the cell walls, penetrate the cells, and digest some of the starch granules and protein bodies inside. The embryo also secretes the hormone gibberellin, which stimulates the aleurone cells to produce digestive enzymes as well.

The maltster's aim is to maximize the breakdown of the endosperm cell walls and the grain's production of starch-and protein-digesting enzymes. The cell walls have been adequately weakened by the time that the growing tip of the embryo reaches the end of the kernel, some five to nine days after the grain is first soaked. If the maltster is going to make a pale malt, then he keeps starch digestion to a minimum and malts for a shorter time; for a darker malt that will benefit from more sugars for the browning reactions, he malts for a longer time, and may finish by holding the moist barley at 140180F/6080C to maximize the action of the starch-digesting, sugar-producing enzymes.

Kilning Once the barley reaches the desired balance of enzymes and sugars, the maltster fixes that balance by drying and heating it in a kiln. The dehydration and heat kill the embryo, and they also generate color and flavor. To make malts with high enzyme activities, the maltster dries the barley gently, over about 24 hours, and brings the temperature slowly up to around 180F/80C. Such a malt is pale, and makes a light-colored, light-flavored brew. To make malts that have little enzyme activity but are rich in color and flavor, he kilns the barley at a high temperature, 300360F/150180C, to encourage browning reactions. Dark malts develop flavors that range from toasted to caramelized to sharp, astringent, and smoky. Brewers have many different kinds of malt to choose from - their names include pale or lager, ale, crystal, amber, brown, caramel, chocolate, and black - and often mix two or more malts in a single brew to obtain a particular combination of flavor, color, and enzyme power. Once the barley reaches the desired balance of enzymes and sugars, the maltster fixes that balance by drying and heating it in a kiln. The dehydration and heat kill the embryo, and they also generate color and flavor. To make malts with high enzyme activities, the maltster dries the barley gently, over about 24 hours, and brings the temperature slowly up to around 180F/80C. Such a malt is pale, and makes a light-colored, light-flavored brew. To make malts that have little enzyme activity but are rich in color and flavor, he kilns the barley at a high temperature, 300360F/150180C, to encourage browning reactions. Dark malts develop flavors that range from toasted to caramelized to sharp, astringent, and smoky. Brewers have many different kinds of malt to choose from - their names include pale or lager, ale, crystal, amber, brown, caramel, chocolate, and black - and often mix two or more malts in a single brew to obtain a particular combination of flavor, color, and enzyme power.

Once the malt has been kilned, the dried kernels can be stored for several months until they're needed, when they're ground into a coa.r.s.e powder. They're also made into malt extracts for both commercial and home brewers: the malted barley is soaked in hot water to remove its carbohydrates, enzymes, color, and flavor, and the liquid then concentrated to a syrup or a dry powder (p. 679).

Brewing Ingredients: Hops Hops are the female flowers, or "cones," of a Eurasian-American vine, Humulus lupulus, Humulus lupulus, which bear small resin and aromatic oil glands near the base of their floral leaves, or bracts. They are an essential flavoring ingredient in beers. There are now several dozen brewing varieties, most of them European or European-American hybrids. Hops are picked off the plant when mature, dried, sometimes powdered and formed into pellets, and then stored until needed. They're added to the brew liquid at the rate of about 0.5 to 5 grams per quart/liter, with the low figure typical of bland commercial brews, the high figure of flavorful microbrews and traditional Pilsners. which bear small resin and aromatic oil glands near the base of their floral leaves, or bracts. They are an essential flavoring ingredient in beers. There are now several dozen brewing varieties, most of them European or European-American hybrids. Hops are picked off the plant when mature, dried, sometimes powdered and formed into pellets, and then stored until needed. They're added to the brew liquid at the rate of about 0.5 to 5 grams per quart/liter, with the low figure typical of bland commercial brews, the high figure of flavorful microbrews and traditional Pilsners.

Four stages in the malting process. As the barley kernel germinates, it generates digestive enzymes, weakens cell walls, and begins the process of converting starch into fermentable sugars. The shading indicates the progress of cell-wall weakening and starch digestion. Malting is stopped when the growing shoot just reaches the tip of the kernel.

Bitterness and Aroma Hops provide two different elements: bitterness from phenolic "alpha acids" in their resins, and aroma from their essential oil. Some hop varieties contribute a dependable level of bitterness, while others are prized for their aroma. The important bittering compounds are the alpha acids humulone and lupulone. In their native form they're not very soluble in water, but prolonged boiling transforms them into soluble structures that flavor the beer effectively. (Brewers sometimes use hop extracts that have been pretreated to produce the more soluble alpha acids.) Because boiling evaporates away many of the volatile aroma compounds, another dose of hops is sometimes added to the brew after the boiling, specifically to add aroma. The aroma of ordinary hops is characterized by the terpene myrcene, which is also found in bay leaf and verbena, and is woody and resinous. "n.o.ble" hop varieties are dominated by humulene, which is more delicate, and often contain pine and citrus notes from other terpenes (pinene, limonene, citral). The American variety "Cascades" has a distinctive floweriness (due to linalool and geraniol). Hops provide two different elements: bitterness from phenolic "alpha acids" in their resins, and aroma from their essential oil. Some hop varieties contribute a dependable level of bitterness, while others are prized for their aroma. The important bittering compounds are the alpha acids humulone and lupulone. In their native form they're not very soluble in water, but prolonged boiling transforms them into soluble structures that flavor the beer effectively. (Brewers sometimes use hop extracts that have been pretreated to produce the more soluble alpha acids.) Because boiling evaporates away many of the volatile aroma compounds, another dose of hops is sometimes added to the brew after the boiling, specifically to add aroma. The aroma of ordinary hops is characterized by the terpene myrcene, which is also found in bay leaf and verbena, and is woody and resinous. "n.o.ble" hop varieties are dominated by humulene, which is more delicate, and often contain pine and citrus notes from other terpenes (pinene, limonene, citral). The American variety "Cascades" has a distinctive floweriness (due to linalool and geraniol).

Brewing Beer The brewing of beer takes place in several stages.

Mas.h.i.+ng: ground barley malt is soaked in hot water. This revives the barley enzymes, which break starch into sugar chains and sugars, and protein into amino acids. The result is a sweet, brown liquid called the wort. wort.

Boiling: hops are added to the wort, and the two are boiled together. This treatment extracts the hop resins that flavor the beer, inactivates the enzymes, kills any microbes present, deepens the color of the wort, and concentrates it.

Fermentation: yeasts are added to the cooled wort and allowed to consume sugars and produce alcohol until the desired levels of each are reached.

Conditioning: the new beer is held for some time to purge it of off-flavors, clear it of yeasts and other materials that give it a cloudy appearance, and develop carbonation.

Here are some details of each stage.

The hop vine, Humulus lupulus, Humulus lupulus, and its female flower structure, the cone, with a close-up of one of the cone's cl.u.s.tered leaves, or bracts. and its female flower structure, the cone, with a close-up of one of the cone's cl.u.s.tered leaves, or bracts.

Brewing Beer Mas.h.i.+ng In the stage known as mas.h.i.+ng, the coa.r.s.ely ground malt is soaked in water at between 130 and 160F/5470C for a couple of hours. Typical proportions are around eight parts water per one part malt. Mas.h.i.+ng is completed by running the wort off the solid remains of the malt, which are then rinsed with hot water - "sparged" - to remove some remaining extractable materials before being discarded. In the stage known as mas.h.i.+ng, the coa.r.s.ely ground malt is soaked in water at between 130 and 160F/5470C for a couple of hours. Typical proportions are around eight parts water per one part malt. Mas.h.i.+ng is completed by running the wort off the solid remains of the malt, which are then rinsed with hot water - "sparged" - to remove some remaining extractable materials before being discarded.

Mas.h.i.+ng accomplishes several purposes. Above all, it gelates the starch granules and allows the barley's enzymes to break down long starch molecules into shorter sugar chains and small fermentable sugars, and proteins into foam-stabilizing amino-acid chains and fermentable single amino acids. And it extracts all these substances, along with color and flavor substances, from the grain particles and into the water.

Because the different enzymes work fastest at different temperatures, the brewer can adjust the ratio of fermentable sugars to sugar chains, and amino acids to amino-acid chains, by varying the temperature and time of mas.h.i.+ng. By this means he controls the beer's final body, and the stability of its foam. Fully 85% of the carbohydrate in malt is starch. In the liquid wort, 70% or more is in the form of various sugars, mainly the two-glucose sugar called maltose. Most of the remaining carbohydrates, 5 to 25% of the dissolved solids, are the so-called dextrins, dextrins, or sugar chains of from four glucose units to a few hundred, which get tangled up with each other, impede the movement of the water, and so provide a full-bodied consistency to the wort and beer. The dextrins and amino-acid chains will also slow the draining of fluid from the bubble walls of the beer foam, and so contribute to its stability in the gla.s.s. or sugar chains of from four glucose units to a few hundred, which get tangled up with each other, impede the movement of the water, and so provide a full-bodied consistency to the wort and beer. The dextrins and amino-acid chains will also slow the draining of fluid from the bubble walls of the beer foam, and so contribute to its stability in the gla.s.s.

Cereal Adjuncts Making the wort with nothing but barley malt and hot water is the standard method in Germany, and in many U.S. microbreweries. In most large breweries in the United States and elsewhere, unmalted "adjunct" sources of carbohydrate - ground or flaked rice, corn, wheat, barley, even sugar - are commonly added to the liquid to lower the amount of malt needed, and so the brewer's production costs. Unlike malt, they contribute little or no flavor of their own. They're therefore mostly limited to pale, mild brews like standard American lagers, which may start with almost as much adjunct grain as malt. Making the wort with nothing but barley malt and hot water is the standard method in Germany, and in many U.S. microbreweries. In most large breweries in the United States and elsewhere, unmalted "adjunct" sources of carbohydrate - ground or flaked rice, corn, wheat, barley, even sugar - are commonly added to the liquid to lower the amount of malt needed, and so the brewer's production costs. Unlike malt, they contribute little or no flavor of their own. They're therefore mostly limited to pale, mild brews like standard American lagers, which may start with almost as much adjunct grain as malt.

Water Water is the main ingredient in beer, so its quality has a definite influence on beer quality. Though modern brewers can tailor the mineral content of their water to the kind of beer they're making, early brewers tailored their beers in part to make the best of the local waters. The sulfate-rich water of Burton-on-Trent gave English pale ales a bitterness that limited the use of hops, while the mild water of Pilsen encouraged Czech brewers to add large amounts of bitter and aromatic hops. The alkaline, carbonate-rich waters of Munich, southern England, and Dublin can balance the acidity of dark malts that normally extract too much astringent material from barley husks, and encouraged the development of dark German beers and British porters and stouts. Water is the main ingredient in beer, so its quality has a definite influence on beer quality. Though modern brewers can tailor the mineral content of their water to the kind of beer they're making, early brewers tailored their beers in part to make the best of the local waters. The sulfate-rich water of Burton-on-Trent gave English pale ales a bitterness that limited the use of hops, while the mild water of Pilsen encouraged Czech brewers to add large amounts of bitter and aromatic hops. The alkaline, carbonate-rich waters of Munich, southern England, and Dublin can balance the acidity of dark malts that normally extract too much astringent material from barley husks, and encouraged the development of dark German beers and British porters and stouts.

Boiling the Wort Once the liquid wort has been drawn off the grain solids, the brewer runs it into a large metal tank, adds hops, and boils it vigorously for up to 90 minutes. Boiling converts the insoluble hop alpha acids into their soluble form and develops the beer's bitterness, and inactivates the barley enzymes and so fixes the carbohydrate mix - a certain portion of sugar for the yeasts to convert into alcohol, a certain portion of dextrins for the beer's body. It sterilizes the wort so that the brewing yeasts won't have any compet.i.tion during fermentation, and it concentrates the wort by evaporating off some of its water. Boiling deepens the wort's color by encouraging browning reactions, mainly between the sugar maltose and the amino acid proline. And it begins the process of clarifying the brew by coagulating large proteins and causing them to bind with tannins from the barley hulls, form large ma.s.ses, and precipitate out of the solution. When boiling is finished, the wort is strained, then cooled and aerated. Once the liquid wort has been drawn off the grain solids, the brewer runs it into a large metal tank, adds hops, and boils it vigorously for up to 90 minutes. Boiling converts the insoluble hop alpha acids into their soluble form and develops the beer's bitterness, and inactivates the barley enzymes and so fixes the carbohydrate mix - a certain portion of sugar for the yeasts to convert into alcohol, a certain portion of dextrins for the beer's body. It sterilizes the wort so that the brewing yeasts won't have any compet.i.tion during fermentation, and it concentrates the wort by evaporating off some of its water. Boiling deepens the wort's color by encouraging browning reactions, mainly between the sugar maltose and the amino acid proline. And it begins the process of clarifying the brew by coagulating large proteins and causing them to bind with tannins from the barley hulls, form large ma.s.ses, and precipitate out of the solution. When boiling is finished, the wort is strained, then cooled and aerated.

OPPOSITE: Making beer. Beer is made in two basic ways. Ales are fermented in less than a week at a warm temperature and matured for days, while lagers are fermented for more than a week at a cold temperature and matured for weeks. Making beer. Beer is made in two basic ways. Ales are fermented in less than a week at a warm temperature and matured for days, while lagers are fermented for more than a week at a cold temperature and matured for weeks.

Fermentation With boiling, the brewer has finished transforming the bland barley grain into a rich, sweet liquid. Now the yeast cells transform this liquid into beer, which is far less sweet, but more complex in flavor. With boiling, the brewer has finished transforming the bland barley grain into a rich, sweet liquid. Now the yeast cells transform this liquid into beer, which is far less sweet, but more complex in flavor.

There are two basic methods for fermenting beer, and they produce distinctive results. One is rapid fermentation at a high temperature with ale yeasts (strains of Saccharomyces cerevisiae Saccharomyces cerevisiae) that clump together, trap the carbon dioxide gas that they produce, and rise to the wort surface. The other is slow fermentation at a low temperature with lager yeasts (Saccharomyces uvarum or or carlsbergensis carlsbergensis) that remain submerged in the wort and fall to the bottom when fermentation is over. These are often called "top" and "bottom" fermentations.

Top fermentation is usually carried out at between 64 and 77F/1825C and takes two to seven days, during which the yeasty foam is skimmed off several times. Because the yeast layer at the top has a good supply of oxygen and is inevitably contaminated by other airborne microbes, including lactic-acid bacteria, top-fermented beers are often relatively acidic and strong in flavor. Bottom fermentation goes on at distinctly lower temperatures, 43 to 50F/610C, takes six to ten days, and produces a milder flavor. Bottom fermentation is the standard technique in the United States. Because warm temperatures encourage yeasts to generate particular aroma compounds (esters, volatile phenols), top fermentation produces fruity, spicy aromas; cold, slow fermentation produces crisp beers with a dry, bready flavor.

Conditioning The treatment of beer after fermentation varies according to the type of fermentation that has taken place: brief for fast top fermentation, prolonged for slow bottom fermentation. The treatment of beer after fermentation varies according to the type of fermentation that has taken place: brief for fast top fermentation, prolonged for slow bottom fermentation.

Top-fermented beer is cleared of yeast and then run into a tank or cask for conditioning. The green beer, as it's called fresh from fermentation, contains little carbon dioxide, has a sulfurous, harsh flavor, and is hazy with the detritus of dead yeast cells. In conditioning, a secondary fermentation is induced by adding to the green beer either a small amount of yeast and some sugar or fresh wort, or some actively fermenting wort (this is called Krausening Krausening). Inside the closed cask or tank, the liquid traps and absorbs the carbon dioxide produced. Undesirable odors can be forced out of the beer by opening the container briefly and allowing some gas to escape. These traditional techniques are sometimes replaced by simply pumping pure carbon dioxide into the beer - carbonating it. Some hops or hop extract may also be added at this point to augment aroma, bitterness, or both. A few days of cooling and the use of a "fining" agent - isingla.s.s (fish gelatin), clay, and vegetable gums are common - precipitate suspended proteins and tannins that might later form a haze when the beer is chilled for drinking; this is called "cold stabilization." The beer is then centrifuged to remove any remaining yeast and precipitate, filtered, packaged, and usually pasteurized.

The Different Flavor of Beer on TapBottled and canned beers and ales are generally cold stabilized and pasteurized (at 140160F/6070C) to survive extreme temperatures during s.h.i.+pping and storage, while keg beers, which are kept refrigerated continuously, may not be. This is why bottle and keg versions of the same beer can taste very different. However, even keg beer is a world apart from the traditional cask-conditioned cask-conditioned beer. Keg beer has been cleared of all its yeast before the keg is filled, while in cask conditioning, the new beer and the yeast that will help mature it are sealed together in the cask. Cask-conditioned beer is thus in contact with yeast until the moment it's dispensed, and its flavor reflects this. Cask beer is fragile and has a drinkable life of about a month, compared with three months for keg beer. beer. Keg beer has been cleared of all its yeast before the keg is filled, while in cask conditioning, the new beer and the yeast that will help mature it are sealed together in the cask. Cask-conditioned beer is thus in contact with yeast until the moment it's dispensed, and its flavor reflects this. Cask beer is fragile and has a drinkable life of about a month, compared with three months for keg beer.

Lagering The conditioning process for bottom-fermented beer is somewhat different. The original Bavarian lager was packed in ice and allowed to rest in contact with its yeast dregs for several months. The yeast slowly produced carbon dioxide, which helped purge the beer of sulfury off-odors. Today, some traditional lagers are still aged for several months; but because storage has the economic disadvantage of tying up money and materials, the tendency is to lager the green beer at temperatures just above freezing for two to three weeks. Carbon dioxide may be pumped in to purge undesired aromas; and centrifuges, filters, and additives help clarify the beer. As a replacement for wooden casks, some beech or hazelwood chips may be thrown into the tank for flavor. The conditioning process for bottom-fermented beer is somewhat different. The original Bavarian lager was packed in ice and allowed to rest in contact with its yeast dregs for several months. The yeast slowly produced carbon dioxide, which helped purge the beer of sulfury off-odors. Today, some traditional lagers are still aged for several months; but because storage has the economic disadvantage of tying up money and materials, the tendency is to lager the green beer at temperatures just above freezing for two to three weeks. Carbon dioxide may be pumped in to purge undesired aromas; and centrifuges, filters, and additives help clarify the beer. As a replacement for wooden casks, some beech or hazelwood chips may be thrown into the tank for flavor.

Additives More than 50 additives are permitted in American beer, including preservatives, foaming agents (usually vegetable gums), and enzymes - similar to meat tenderizers - that break down proteins into smaller molecules that are less likely to cloud the brew. Some companies avoid the use of preservatives, and usually advertise this fact on the label. More than 50 additives are permitted in American beer, including preservatives, foaming agents (usually vegetable gums), and enzymes - similar to meat tenderizers - that break down proteins into smaller molecules that are less likely to cloud the brew. Some companies avoid the use of preservatives, and usually advertise this fact on the label.

The Finished Beer In the end, brewing has transformed the dry, tasteless barley grain into a bubbly, bitter, acidic liquid (its pH is about 4) that is 90% water, 1 to 6% alcohol, and between 2 and 10% carbohydrates, mainly the long-chain dextrins that provide body. In the end, brewing has transformed the dry, tasteless barley grain into a bubbly, bitter, acidic liquid (its pH is about 4) that is 90% water, 1 to 6% alcohol, and between 2 and 10% carbohydrates, mainly the long-chain dextrins that provide body.

Storing and Serving Beer In contrast to wines, with their higher alcohol and antioxidant contents, most beers do not improve with age, and are at their best fresh from the brewery. Oxidation causes the gradual development of a stale, cardboard aroma (from nonenal, a fatty-acid fragment) and harshness on the tongue (from hop phenolic substances). Browning reactions cause other undesirable changes. Top-fermented ales develop a solvent-like note. Staling is slowed at low temperatures, so when possible beer should be stored in the cold. Britain does make "laying-down beers," and Belgium bieres de garde, bieres de garde, which start out fermentation with a very high soluble carbohydrate content and continue to ferment slowly in the bottle, the continuous production of carbon dioxide and other substances helping to prevent oxidation and staling. They end with alcohol levels of 8% or more, and improve for a year or two. which start out fermentation with a very high soluble carbohydrate content and continue to ferment slowly in the bottle, the continuous production of carbon dioxide and other substances helping to prevent oxidation and staling. They end with alcohol levels of 8% or more, and improve for a year or two.

Keep Beer in the Dark Beer should also be kept away from bright light, especially sunlight, and especially if it has been bottled in clear or green gla.s.s: otherwise it will develop a strong sulfurous odor. A cup of beer at a picnic can go skunky in a few minutes; bottled beer in a fluorescent-lit display case may deteriorate in a few days. It turns out that light in the blue-green to ultraviolet parts of the light spectrum reacts with one of the hop acids to form an unstable free radical, which in turn reacts with sulfur compounds to form a close relative of chemicals in the skunk's defensive a.r.s.enal. Brown gla.s.s can absorb blue-green wavelengths before they get to the beer inside, but green bottles don't. As a result, green-bottled German and Dutch beers are often sulfurous, and many consumers now expect this! One American brewer with trademark clear bottles developed a modified hop extract that's free of the vulnerable hop acid, and this prevents its beer from going skunky. Beer should also be kept away from bright light, especially sunlight, and especially if it has been bottled in clear or green gla.s.s: otherwise it will develop a strong sulfurous odor. A cup of beer at a picnic can go skunky in a few minutes; bottled beer in a fluorescent-lit display case may deteriorate in a few days. It turns out that light in the blue-green to ultraviolet parts of the light spectrum reacts with one of the hop acids to form an unstable free radical, which in turn reacts with sulfur compounds to form a close relative of chemicals in the skunk's defensive a.r.s.enal. Brown gla.s.s can absorb blue-green wavelengths before they get to the beer inside, but green bottles don't. As a result, green-bottled German and Dutch beers are often sulfurous, and many consumers now expect this! One American brewer with trademark clear bottles developed a modified hop extract that's free of the vulnerable hop acid, and this prevents its beer from going skunky.

Serving Beer In the United States, beer is often drunk ice-cold and straight from the can or bottle. This is fine for a light, thirst-quenching beer, but doesn't do justice to beers designed to have some character. The colder any food is, the less full its flavor will seem. Lager beers are usually best served somewhat warmer than refrigerator temperature, around 50F/10 C, while top-fermented ales are served at a cool room temperature, from 50 to 60F/1015C. Beers worth savoring are poured into a gla.s.s, where some of the carbon dioxide gas can escape and moderate their p.r.i.c.kliness, and where their color and head of foam can be appreciated. In the United States, beer is often drunk ice-cold and straight from the can or bottle. This is fine for a light, thirst-quenching beer, but doesn't do justice to beers designed to have some character. The colder any food is, the less full its flavor will seem. Lager beers are usually best served somewhat warmer than refrigerator temperature, around 50F/10 C, while top-fermented ales are served at a cool room temperature, from 50 to 60F/1015C. Beers worth savoring are poured into a gla.s.s, where some of the carbon dioxide gas can escape and moderate their p.r.i.c.kliness, and where their color and head of foam can be appreciated.

Beer Foam: The "Head" Beer is not the only intrinsically bubbly liquid we enjoy, but it's the only one whose bubbles we expect to persist long enough to form a "head" of foam atop the gla.s.s. Beer lovers even value the ability of the foam to cling to the gla.s.s as the liquid level drops, a quality known as Beer is not the only intrinsically bubbly liquid we enjoy, but it's the only one whose bubbles we expect to persist long enough to form a "head" of foam atop the gla.s.s. Beer lovers even value the ability of the foam to cling to the gla.s.s as the liquid level drops, a quality known as lacing lacing (or, in more impressive German, (or, in more impressive German, Schaumhaftvermogen Schaumhaftvermogen). There are many factors that influence foaming, from the amount of carbon dioxide dissolved in the beer to the way the beer is released from keg or can. Here are some of the most interesting.

Grain Proteins Stabilize the Head Foam stability depends on the presence in the bubble walls of emulsifier molecules with water-loving and water-avoiding ends (p. 802); the water-avoiding ends project into the gas while the water-loving ends stay in the liquid, and thus reinforce the gas-liquid interface. In beer, these molecules are mostly medium-sized proteins that come from the malt or from cereal adjuncts, whose proteins are more intact than malt's and significantly improve head stability. Hop acids also contribute to foam stability, and become concentrated enough in the foam to make it noticeably more bitter than the liquid beneath. Cool-fermented lagers generally give more persistent foams than warm-fermented ales because the latter contain more foam-destabilizing higher alcohols from yeast metabolism (p. 762). Foam stability depends on the presence in the bubble walls of emulsifier molecules with water-loving and water-avoiding ends (p. 802); the water-avoiding ends project into the gas while the water-loving ends stay in the liquid, and thus reinforce the gas-liquid interface. In beer, these molecules are mostly medium-sized proteins that come from the malt or from cereal adjuncts, whose proteins are more intact than malt's and significantly improve head stability. Hop acids also contribute to foam stability, and become concentrated enough in the foam to make it noticeably more bitter than the liquid beneath. Cool-fermented lagers generally give more persistent foams than warm-fermented ales because the latter contain more foam-destabilizing higher alcohols from yeast metabolism (p. 762).

Nitrogen Makes Creamy Foams In the last decade, many beers have come to be endowed with an especially fine, creamy head that used to be largely limited to stouts. The creamy head comes from an artificial dose of nitrogen gas that may be injected into beer at the brewery, or in the bar or pub by the tap that delivers beer from the keg, or by a small device inside an individual beer can. Nitrogen is less soluble in water than carbon dioxide, so its bubbles are slower to lose gas to the surrounding liquid, and slower to coa.r.s.en and deflate. Nitrogen bubbles remain small, and persist. They also don't carry the tart p.r.i.c.kliness of carbon dioxide, which becomes carbonic acid when it dissolves in beer and on the surface of our tongue. In the last decade, many beers have come to be endowed with an especially fine, creamy head that used to be largely limited to stouts. The creamy head comes from an artificial dose of nitrogen gas that may be injected into beer at the brewery, or in the bar or pub by the tap that delivers beer from the keg, or by a small device inside an individual beer can. Nitrogen is less soluble in water than carbon dioxide, so its bubbles are slower to lose gas to the surrounding liquid, and slower to coa.r.s.en and deflate. Nitrogen bubbles remain small, and persist. They also don't carry the tart p.r.i.c.kliness of carbon dioxide, which becomes carbonic acid when it dissolves in beer and on the surface of our tongue.

Foam in the Gla.s.s An initially vigorous pouring action develops the head of foam with a small, easily controlled portion of the beer. Once the foam is of the desired thickness, the rest of the beer can be poured in gently along the side of the gla.s.s, avoiding aeration and nucleation of new bubbles. The gla.s.s itself should be clean of any residues of oil or soap, which interfere with foaming. (These molecules have water-avoiding ends that pull the similar ends of the bubble-stabilizing proteins out of the bubbles.) By the same token, if a newly poured beer threatens to foam over, it can often be stopped in its tracks by touching the rim with a finger or lip, which carry traces of oil. An initially vigorous pouring action develops the head of foam with a small, easily controlled portion of the beer. Once the foam is of the desired thickness, the rest of the beer can be poured in gently along the side of the gla.s.s, avoiding aeration and nucleation of new bubbles. The gla.s.s itself should be clean of any residues of oil or soap, which interfere with foaming. (These molecules have water-avoiding ends that pull the similar ends of the bubble-stabilizing proteins out of the bubbles.) By the same token, if a newly poured beer threatens to foam over, it can often be stopped in its tracks by touching the rim with a finger or lip, which carry traces of oil.

Kinds and Qualities of Beer Beers are a wonderfully diverse group of drinks, and a good beer can be a mouth-filling experience, one that rewards slow savoring. There are several qualities worth appreciating: Color, which can range from pale yellow to impenetrable brown-black, and comes from the kinds of malt used Body, or weightiness in the mouth, which comes from the long remnants of starch molecules in the malt Astringency, from malt phenolic compounds p.r.i.c.kly freshness, from dissolved carbon dioxide Taste, which may include saltiness from the water, sweetness from unfermented malt sugars, acidity from roasted malt and from fermentation microbes, bitterness from hops and from dark-roasted malts, savoriness from malt amino acids Aroma, from woody, floral, citrusy hops; malty, caramel, and even smoky malt; and from the yeasts and other microbes, which can produce notes that seem fruity (apple, pear, banana, citrus), flowery (rose), b.u.t.tery, spicy (clove), and even horsey or stable-like (p. 738) Ales develop a characteristic tartness and fruitiness from their diverse group of fermentation microbes. Lagers have a more subdued aroma, part of whose foundation is cooked-corn-like DMS (dimethyl sulfide), which comes from a precursor in the lightly roasted malt and is produced while the wort is boiled and then cooled. But there's tremendous variation in the flavors of these basic beers. Rich and somewhat sweet brews - porter, stout, barley wine - can even go well with desserts.

In addition to the many variations on the two themes of beer and ale, there are two kinds of beer that are worth special mention for their distinctiveness.

Beers Low in Calories, Alcohol, and Beer FlavorNowadays there are versions of beer for people who like beer but don't want to consume alcohol, or want to consume alcohol but reduce their intake of calories. A standard 12 oz/360 ml container of American lager contains about 14 grams of alcohol and 11 grams of carbohydrate, for a total of about 140 calories. Low-calorie "light" or "dry" beers have 100110 calories, a savings produced by using a lower proportion of malt and adjuncts to water, and then adding enzymes that digest more of the carbohydrates into fermentable sugars. The fermentation then produces a brew with only a slightly lower alcohol content, but about half the sugar chains - and very little body."Nonalcoholic beers" can be made by modifying the fermentation so that the yeasts produce little alcohol (very low temperatures, abundant oxygen), or by removing the alcohol from normally fermented beer using a molecular version of sieving called "reverse osmosis." The lowest-alcohol malt product is "malta," a popular drink in the Caribbean made by bottling a full-fledged wort without any fermentation at all. It is dense and sweet.Then there are "malt beverages," which have the alcohol and calorie content of beer, but taste nothing like beer: they're more like soft drinks. In these products, the only purpose of the malt is to generate sugars for fermentation into alcohol; neither it nor the yeast contributes any flavor.Some Styles and Qualities of Beer

Beer Style

Pale lager: European Pale lager: European

Alcohol Content, Percent by Volume

46 46

Unusual Ingredients

Qualities