Proportions The consistency of a custard can be firm or soft, slick or creamy, depending on its egg content. The greater the proportion of whole eggs or whites, the firmer and glossier the custard. Extra yolks, or using yolks alone, will produce a more tender, creamier effect. A custard to be served in the container it was cooked in can be as soft as the cook desires. Those that are to be turned out of a container for serving must be firm enough to stand on their own, which means that they must contain either some egg whites or at least 3 yolks per cup/250 ml of liquid (the LDL-bound yolk proteins are less efficient networkers than the free-floating alb.u.men proteins, so we need more of them to make a firm gel). The replacement of some or all of the milk with cream reduces the proportion of eggs required for a given firmness, since cream contains 20 to 40% less water and the egg proteins are proportionally less diluted. Unmolding is easiest from a b.u.t.tered ramekin, and when the custards have been allowed to cool thoroughly; cooling firms protein gels. The consistency of a custard can be firm or soft, slick or creamy, depending on its egg content. The greater the proportion of whole eggs or whites, the firmer and glossier the custard. Extra yolks, or using yolks alone, will produce a more tender, creamier effect. A custard to be served in the container it was cooked in can be as soft as the cook desires. Those that are to be turned out of a container for serving must be firm enough to stand on their own, which means that they must contain either some egg whites or at least 3 yolks per cup/250 ml of liquid (the LDL-bound yolk proteins are less efficient networkers than the free-floating alb.u.men proteins, so we need more of them to make a firm gel). The replacement of some or all of the milk with cream reduces the proportion of eggs required for a given firmness, since cream contains 20 to 40% less water and the egg proteins are proportionally less diluted. Unmolding is easiest from a b.u.t.tered ramekin, and when the custards have been allowed to cool thoroughly; cooling firms protein gels.

Food Words: Custard, Cream, Flan Custard, Cream, FlanThe nomenclature for egg-milk mixtures has always been loose. The English "custard" began as "croustade" in medieval times, and meant dishes served in a crust - thus, for egg-milk combinations, usually baked and unstirred, and so solid. Early English creams could be either liquid or solid, as could the French cremes. cremes. Those congealed past the point of creaminess became known as Those congealed past the point of creaminess became known as cremes prises, cremes prises, or "set creams." or "set creams."Flan, a French word, comes from the late Latin for "flat cake." a French word, comes from the late Latin for "flat cake."

Custards that contain fruits or vegetables can turn out very uneven, with pockets of fluid and curdling. (Usually this is undesirable, though the j.a.panese expect chawan-mushi chawan-mushi to weep and treat it as a combination of custard and soup.) The culprits are juices that leak out of the plant tissue, and fibrous particles, which cause local overcoagulation of egg proteins. The juice leakage can be reduced by precooking the fruit or vegetable, and including some flour in the mix to help bind excess liquid and minimize overcoagulation. These dishes are best cooked very gently and only until barely done. to weep and treat it as a combination of custard and soup.) The culprits are juices that leak out of the plant tissue, and fibrous particles, which cause local overcoagulation of egg proteins. The juice leakage can be reduced by precooking the fruit or vegetable, and including some flour in the mix to help bind excess liquid and minimize overcoagulation. These dishes are best cooked very gently and only until barely done.

Cooking Cooks have known for thousands of years that a low cooking temperature provides the greatest safety margin for making custards: that is, it gives us more time to recognize that the dish is properly done and remove it from the heat, before it toughens and tunnels. Custards are usually baked in a moderate oven with the protection of a water bath, which keeps the effective cooking temperature below the boiling point. The actual temperature depends on the pan material and whether and how the water bath is covered (see box). It's a mistake to cover the whole water bath, since this forces the water to the boil and makes it more likely that the custards will be overcooked. The most gentle heating results when the individual molds are set covered on a rack in an open, thin metal pan of hot water. Cooks have known for thousands of years that a low cooking temperature provides the greatest safety margin for making custards: that is, it gives us more time to recognize that the dish is properly done and remove it from the heat, before it toughens and tunnels. Custards are usually baked in a moderate oven with the protection of a water bath, which keeps the effective cooking temperature below the boiling point. The actual temperature depends on the pan material and whether and how the water bath is covered (see box). It's a mistake to cover the whole water bath, since this forces the water to the boil and makes it more likely that the custards will be overcooked. The most gentle heating results when the individual molds are set covered on a rack in an open, thin metal pan of hot water.

Custard doneness can be judged by b.u.mping the dish - the contents should move only sluggishly - or by probing the interior with a toothpick or knife, which should return without any mix clinging to it. When the proteins have coagulated enough that the mix clings mostly to itself, the dish is done. Unless the custard needs to be firm enough to unmold, it's best taken from the oven while the center is still slightly underdone and jiggly. The egg proteins continue to set somewhat with the residual heat, and the custard will in any case be firmer once cooled to serving temperature.

"Ribboning" Yolks with SugarCookbooks often a.s.sert the importance of beating yolks with sugar until they lighten in color and thicken sufficiently to form a ribbon when trailed from a spoon. This stage does not mark any critical change in the yolk components. It's simply a sign that much of the sugar has dissolved in the limited yolk water (about half the volume of the yolks themselves), which makes the mix viscous enough to pour thickly and retain air bubbles (the cause of the whitening). Sugar grains are a convenient means for mixing the yolks and alb.u.men remnants thoroughly, but the quality of a cream or custard will not suffer if you mix the yolks and sugar thoroughly but stop short of the ribbon.

Savory Custards: The Quiche The quiche (a French version of the German The quiche (a French version of the German Kuchen, Kuchen, "little cake") can be thought of either as a savory custard or a close relative of the omelet. It is a pie-shaped mixture of eggs and cream or milk that contains small pieces of a vegetable, meat, or cheese. To make it firm enough to be cut into wedges for serving, a quiche normally contains 2 whole eggs per cup/250 ml of liquid, and is baked unprotected by a water bath, either alone or in a precooked crust. The Italian "little cake") can be thought of either as a savory custard or a close relative of the omelet. It is a pie-shaped mixture of eggs and cream or milk that contains small pieces of a vegetable, meat, or cheese. To make it firm enough to be cut into wedges for serving, a quiche normally contains 2 whole eggs per cup/250 ml of liquid, and is baked unprotected by a water bath, either alone or in a precooked crust. The Italian frittata frittata and Egyptian and Egyptian eggah eggah are similar preparations that omit any milk or cream. are similar preparations that omit any milk or cream.

Creme Caramel and Creme Brulee Creme caramel is a freestanding sweet custard with a layer of moist caramel on top. It's made by coating the bottom of the dish with a layer of caramelized sugar (see p. 656) before the custard mix is poured in and cooked. The caramel does harden and stick to the dish, but moisture from the custard mix softens it, and the two layers become partly integrated. The custard is turned out of the dish while still slightly warm and the caramel soft. If the custard must be refrigerated before serving, leave it in the mold; the caramel can be softened again by placing the dish in a shallow pan of hot water for a minute or two before unmolding. Creme caramel is a freestanding sweet custard with a layer of moist caramel on top. It's made by coating the bottom of the dish with a layer of caramelized sugar (see p. 656) before the custard mix is poured in and cooked. The caramel does harden and stick to the dish, but moisture from the custard mix softens it, and the two layers become partly integrated. The custard is turned out of the dish while still slightly warm and the caramel soft. If the custard must be refrigerated before serving, leave it in the mold; the caramel can be softened again by placing the dish in a shallow pan of hot water for a minute or two before unmolding.

Creme brulee ("burned cream") is also a custard topped with caramel, but here the caramel should be hard enough to shatter when rapped with a spoon. The trick is to harden and brown the sugar topping without overcooking the custard. The standard modern method is to bake the custard and then chill it for several hours, so that the subsequent caramelizing step won't overcook the egg proteins. The hard crust is then made by coating the custard surface with granulated sugar, and then melting and browning the sugar, either with a propane torch or by placing the dish right under the broiler. The dishes are sometimes immersed in an ice-water bath to protect the custard from a second cooking. From the time of its invention in the 17th century until early in the 20th, creme brulee was a stirred cream, prepared on the stovetop by making a creme anglaise, pouring it into dishes, and caramelizing the sugar topping with a red-hot metal plate, or "salamander."

The Surprising Science of Water BathsMost cooks know that oven heat can be moderated with a water bath. Though the oven may be at 350F, the liquid water can't exceed 212F/100C, the temperature at which it boils and turns from liquid into vapor. Less well known is the fact that the water temperature can vary over a range of 40F depending on the pan containing the water and whether it's covered. A pan of water is heated by the oven, but it's simultaneously cooled as water molecules evaporate from the surface. The actual water temperature is determined by the balance between heating of the water ma.s.s through the pan, and evaporative cooling at the water surface. More heat acc.u.mulates in a thick cast iron pan or pa.s.ses through infrared-transparent gla.s.s than is transmitted by thin stainless steel. So in a moderate oven, a cast-iron water bath may reach 195F/87C, a gla.s.s bath 185F/ 83C, and a stainless one 180F/80C. If the pans are covered with foil, then evaporative cooling is prevented, and all of them will come to a full boil.Custards are tenderest when heated gently, and so are best cooked in an open water bath - one, however, that is sure to reach at least 185F; otherwise the mix may never completely set. Many cooks take the precaution of folding a kitchen towel in the bottom of the water bath so that the custard cups or dish won't be in direct contact with the hot pan, but this can backfire: the towel prevents the water from circulating under the cups, so the water trapped there reaches the boil and rocks the cups around. A wire rack works better.

Cheesecake We don't ordinarily think of cheesecake as a custard, probably because the presence of eggs is masked by the richness of the filling they bind together, which is some combination of ricotta cheese, cream cheese, sour cream, heavy cream, and b.u.t.ter. The proportions for cheesecake are similar to those for other custards, approaching 1 egg per cup/250 ml of filling, though the greater richness and tartness of the filling demand more sugar for balance, around 4 tablespoons per cup (60 gm per 250 ml) instead of 2. Flour or cornstarch is sometimes included to stabilize the gel and, in the case of ricotta cheesecakes, to absorb water that may be released from the fresh cheese. We don't ordinarily think of cheesecake as a custard, probably because the presence of eggs is masked by the richness of the filling they bind together, which is some combination of ricotta cheese, cream cheese, sour cream, heavy cream, and b.u.t.ter. The proportions for cheesecake are similar to those for other custards, approaching 1 egg per cup/250 ml of filling, though the greater richness and tartness of the filling demand more sugar for balance, around 4 tablespoons per cup (60 gm per 250 ml) instead of 2. Flour or cornstarch is sometimes included to stabilize the gel and, in the case of ricotta cheesecakes, to absorb water that may be released from the fresh cheese.

The thick texture and high fat content of cheesecake filling necessitate more delicate treatment than a standard custard. Instead of a preliminary cooking on the stovetop, the sugar is first mixed into the cream ingredients, and the eggs then incorporated along with other flavorings. The cool mix is poured into the pan (often preceded by a crumb crust) and baked at a gentle 325F/163C, often in a water bath. The last phase of cooking may take place with the heat off and the oven door ajar, which smooths the transition between cooking and cooling.

First Recipes for Creme Brulee, Creme Anglaise, and Creme CaramelMa.s.sialot's recipe for creme brulee is the first I know of. The identical recipe in the 1731 edition of his book is renamed "Creme a l'Angloise," which may well be the origin of that basic stirred cream. An English model for "English cream" hasn't yet been unearthed.Creme bruleeTake four or five egg yolks, according to the size of your platter. You mix them well in a ca.s.serole with a good pinch of flour; and little by little you pour in some milk, about [3 cups/750 ml]. Add a little stick cinnamon, and chopped green citron peel.... Put on the stovetop and stir continuously, taking care that your cream doesn't stick to the bottom. When it is well cooked, place a platter on the stove, pour the cream onto it, and cook it again until you see it stick to the platter rim. Then remove from the heat and sugar it well: take the fire iron, good and red, and burn the cream so that it takes on a fine gold color.- F. Ma.s.sialot, Le Cuisinier roial et bourgeois, Le Cuisinier roial et bourgeois, 1692 1692A few decades later, Vincent La Chapelle plagiarized Ma.s.sialot's recipe for his own version of creme brulee, which comes close to the modern creme caramel. La Chapelle copies Ma.s.sialot word for word up to the point that the cream is cooked on the stovetop. Then...When the cream is well cooked, put a silver platter onto the hot stove with some powdered sugar and a little water to dissolve it; and when your sugar has colored, pour the cream on top; turn the sugar along the platter rim onto the top of your cream, and serve at once.- V. La Chapelle, Le Cuisinier moderne, Le Cuisinier moderne, 1742 1742 The most common problem with cheesecakes is the development of depressions and cracks in the surface, which result when the mix expands and rises during the cooking, then shrinks and falls as it cools down. Rising is essential for souffles and sponge cakes, but it is ant.i.thetical to the dense richness of cheesecake. Four basic strategies will minimize it. First, beat the ingredients slowly, gently, and only long enough to obtain an even mix. Vigorous or long beating incorporates more air bubbles that will fill with steam and expand during baking. Second, bake the cheesecake slowly in a low oven. This will allow trapped air and steam to disperse gradually and evenly. Third, don't overbake. This will dry the filling and cause it to shrink from moisture loss. Finally, cool the cheesecake gradually in the open oven. Cooling causes any trapped air or steam to contract, and the more gradually this happens, the more gently the cheesecake surface is pulled in.

Cream Theory and Practice Creams are easier to make than custards in two respects. They're heated on the stovetop, so the cook doesn't have to consider the fine points of heat transfer in the oven. And because they're not served as is, in the container they're cooked in, some curdling can be tolerated and remedied by putting the cream through a strainer before it's served.

Pourable and Stiff Creams There are two broad cla.s.ses of creams, and they demand entirely different handling by the cook. The There are two broad cla.s.ses of creams, and they demand entirely different handling by the cook. The pourable creams, pourable creams, creme anglaise for example, are meant to have the consistency of heavy cream at serving temperature. They contain the standard eggs, milk, and sugar (sugar is omitted for a savory cream), and are cooked only until they just begin to thicken, far below the boil. The creme anglaise for example, are meant to have the consistency of heavy cream at serving temperature. They contain the standard eggs, milk, and sugar (sugar is omitted for a savory cream), and are cooked only until they just begin to thicken, far below the boil. The cream fillings cream fillings - creme patissiere, banana cream, and so on - are meant to stay put in a dish and hold their shape. They are therefore stiffened with a substantial dose of flour or cornstarch; and this means not only that they - creme patissiere, banana cream, and so on - are meant to stay put in a dish and hold their shape. They are therefore stiffened with a substantial dose of flour or cornstarch; and this means not only that they can can be heated to the boil, they be heated to the boil, they must must be boiled. Egg yolks contain a starch-digesting enzyme, amylase, that is remarkably resistant to heat. Unless a starch-egg mix is brought to a full boil, the yolk amylase will survive, digest the starch, and turn the stiff cream into a pourable one. be boiled. Egg yolks contain a starch-digesting enzyme, amylase, that is remarkably resistant to heat. Unless a starch-egg mix is brought to a full boil, the yolk amylase will survive, digest the starch, and turn the stiff cream into a pourable one.

When stored for any time, creams should be protected against the formation of the leathery skin that results from evaporation, which concentrates and toughens the surface layer of protein and starch. b.u.t.ter can be dotted onto the warm surface, where the milk fat will melt and spread into a protective layer; and sprinkled sugar will form a layer of concentrated syrup that resists evaporation. The most straightforward solution is to press waxed paper or b.u.t.tered parchment directly onto the cream. Avoid plastic wrap; its plasticizing chemicals tend to migrate into fat-rich foods.

A Medieval CheesecakeTart de bryTake raw yolks of eggs, and good fat cheese, and dress it, and mix it well together; and add powder of ginger, and of cinnamon, and sugar, and saffron, and put it in a crust, and bake it, and serve it forth.- from a ma.n.u.script published in Antiquitates Culinariae, Antiquitates Culinariae, 1791 (ca. 1400) 1791 (ca. 1400) Creme Anglaise and Other Pourable Creams The mix for a stirred cream is made much as baked-custard mixes are. An especially rich cream may call for yolks only, as many as 4 or 5 per cup/250 ml milk. The eggs and sugar are mixed with scalded milk or cream, and the mixture is then stirred constantly on the stovetop until it thickens enough to cling to the spoon, at around 180F/80C. The gentle heat of a double boiler minimizes the possibility of curdling, but it takes longer than direct heat. The thickened cream is then strained of any coagulated egg or other solid particles, and cooled, with occasional stirring to prevent the proteins from setting into a solid gel. An ice bath will cool the cream quickly, but demands more frequent stirring to maintain an even texture. Fruit purees are generally added after the cooling, because their acidity and fibrous particles can cause curdling during the cooking. The mix for a stirred cream is made much as baked-custard mixes are. An especially rich cream may call for yolks only, as many as 4 or 5 per cup/250 ml milk. The eggs and sugar are mixed with scalded milk or cream, and the mixture is then stirred constantly on the stovetop until it thickens enough to cling to the spoon, at around 180F/80C. The gentle heat of a double boiler minimizes the possibility of curdling, but it takes longer than direct heat. The thickened cream is then strained of any coagulated egg or other solid particles, and cooled, with occasional stirring to prevent the proteins from setting into a solid gel. An ice bath will cool the cream quickly, but demands more frequent stirring to maintain an even texture. Fruit purees are generally added after the cooling, because their acidity and fibrous particles can cause curdling during the cooking.

Pastry Cream, Bouillie, Bouillie, and Cream-Pie and Cream-Pie Fillings Fillings Along with creme anglaise, pastry cream is one of the most versatile of the dessert maker's stock preparations. It's used mainly to fill and decorate cakes and pastries, and is a common reinforcing base for sweet souffles; in Italy and France it's even cut into pieces and fried on its own. It must therefore be thick enough to hold its shape at room temperature, and so is stiffened with between 1 and 2 tablespoons flour (or about half that amount of pure starch) per cup liquid/1020 gm per 250 ml. Along with creme anglaise, pastry cream is one of the most versatile of the dessert maker's stock preparations. It's used mainly to fill and decorate cakes and pastries, and is a common reinforcing base for sweet souffles; in Italy and France it's even cut into pieces and fried on its own. It must therefore be thick enough to hold its shape at room temperature, and so is stiffened with between 1 and 2 tablespoons flour (or about half that amount of pure starch) per cup liquid/1020 gm per 250 ml.

Pastry cream is made by adding scalded milk to the mixture of sugar, eggs, and flour, whose protective action allows the mix to be brought to a full boil over direct heat without curdling. After a minute or so of boiling (and constant stirring) to thoroughly inactivate the yolk amylase enzyme and to extract starch from its granules, and to improve the flavor, the thickened cream is sc.r.a.ped into a bowl and allowed to cool with minimal stirring (stirring breaks the developing starch network and thins it out). Once cool, pastry cream is sometimes enriched with cream or b.u.t.ter, or lightened with foamed egg whites, or simultaneously enriched and lightened with whipped cream.

The First Recipe for Pastry CreamPastry cream has been a standard professional preparation for more than three centuries.The Manner of Making Cresme de PastissierTake for example a chopine chopine [3 cups/750 ml] of good milk.... Put the milk in a pot on the fire: you must also have four eggs, and while the milk heats up, break two eggs, and mix the white and yolk with about a half [3 cups/750 ml] of good milk.... Put the milk in a pot on the fire: you must also have four eggs, and while the milk heats up, break two eggs, and mix the white and yolk with about a half litron litron [7 oz/185 gm] flour, as if for making porridge, and a little milk. And when the flour is well diluted so that it has no more lumps, you throw in the other two eggs to mix them well with this preparation. [7 oz/185 gm] flour, as if for making porridge, and a little milk. And when the flour is well diluted so that it has no more lumps, you throw in the other two eggs to mix them well with this preparation.And when the milk begins to boil you pour in little by little this mix of eggs and flour and milk, and boil together on a low flame that is clear and without smoke; stir with a spoon as you would a porridge. You must also add salt at your discretion as it cooks, and a quarteron [a quarter-pound/125 gm] good fresh b.u.t.ter.This cream should be cooked for 20 to 25 minutes, then pour it into a bowl and set aside this preparation, which pastry cooks call cream and use in many baked goods.- Le Patis sier francois, Le Patis sier francois, ca. 1690 ca. 1690 A traditional French variant on pastry cream is the bouillie bouillie (literally "boiled"; the word means a plain porridge-like cereal paste), which is made at the last minute, and primarily to reinforce souffles. For a (literally "boiled"; the word means a plain porridge-like cereal paste), which is made at the last minute, and primarily to reinforce souffles. For a bouillie, bouillie, milk, sugar, and flour are heated together to the boil, removed from the heat, and the eggs beaten in as the mix cools. Because the egg proteins are not as thoroughly heated and coagulated as they are in the technique for pastry cream, the consistency of a milk, sugar, and flour are heated together to the boil, removed from the heat, and the eggs beaten in as the mix cools. Because the egg proteins are not as thoroughly heated and coagulated as they are in the technique for pastry cream, the consistency of a bouillie bouillie is lighter and smoother. Some yolk amylase enzyme survives in a is lighter and smoother. Some yolk amylase enzyme survives in a bouillie, bouillie, but this doesn't matter if the dish is to be made and served immediately; the enzyme takes hours to digest a noticeable amount of starch. but this doesn't matter if the dish is to be made and served immediately; the enzyme takes hours to digest a noticeable amount of starch.

However, the survival of yolk amylase can spell disaster in the fillings for American cream pies, which are often made in the fashion of a bouillie bouillie rather than a pastry cream, and are held for hours or days before serving, enough time for a perfect cream pie to disintegrate into a soupy mess. No matter what a recipe may say, always be sure that the egg yolks in a starch-thickened pie filling are heated all the way to the boil. rather than a pastry cream, and are held for hours or days before serving, enough time for a perfect cream pie to disintegrate into a soupy mess. No matter what a recipe may say, always be sure that the egg yolks in a starch-thickened pie filling are heated all the way to the boil.

Fruit Curds Fruit curds - lemon curd is the most common - can be thought of as a kind of cream in which the place of milk is taken by fruit juice, usually enriched with b.u.t.ter. (They may have begun as a sweetened version of creamy eggs scrambled with fruit juice; see p. 86.) Fruit curds are meant to have a spoonable consistency that works well as a filling for small pastries or a breakfast spread, and must be sweet enough to balance the acidity of the juice. They therefore contain no flour, more sugar, and more eggs than do milk creams, typically 4 eggs (or 8 yolks) and a cup or more of sugar for a half-cup of b.u.t.ter and a half-cup of juice (375 gm sugar per 125 ml each of b.u.t.ter and juice). Fruit curds - lemon curd is the most common - can be thought of as a kind of cream in which the place of milk is taken by fruit juice, usually enriched with b.u.t.ter. (They may have begun as a sweetened version of creamy eggs scrambled with fruit juice; see p. 86.) Fruit curds are meant to have a spoonable consistency that works well as a filling for small pastries or a breakfast spread, and must be sweet enough to balance the acidity of the juice. They therefore contain no flour, more sugar, and more eggs than do milk creams, typically 4 eggs (or 8 yolks) and a cup or more of sugar for a half-cup of b.u.t.ter and a half-cup of juice (375 gm sugar per 125 ml each of b.u.t.ter and juice).

Egg Foams: Cooking with the Wrist If the transformation of eggs by heat seems remarkable, consider what beating can do! Physical agitation normally breaks down and destroys structure. But beat eggs and you create create structure. Begin with a single dense, sticky egg white, work it with a whisk, and in a few minutes you have a cupful of snowy white foam, a cohesive structure that clings to the bowl when you turn it upside down, and holds its own when mixed and cooked. Thanks to egg whites we're able to harvest the air, and make it an integral part of meringues and mousses, gin fizzes and souffles and sabayons. structure. Begin with a single dense, sticky egg white, work it with a whisk, and in a few minutes you have a cupful of snowy white foam, a cohesive structure that clings to the bowl when you turn it upside down, and holds its own when mixed and cooked. Thanks to egg whites we're able to harvest the air, and make it an integral part of meringues and mousses, gin fizzes and souffles and sabayons.

The full foaming power of egg white seems to have burst forth in the early 17th century. Cooks had noticed the egg's readiness to foam long before then, and by Renaissance times were exploiting it in two fanciful dishes: imitation snow and the confectioner's miniature loaves and biscuits. But in those days the fork was still a novelty, and twigs, shreds of dried fruits, and sponges could deliver only a coa.r.s.e froth at best (see box, p. 101). Sometime around 1650, cooks began to use more efficient whisks of bundled straw, and meringues and souffles start to appear in cookbooks.

Like the head on a beer or a cappuccino, an egg foam is a liquid - the white - filled with a gas - air - in such a way that the mixture of liquid and gas keeps its shape, like a solid. It's a ma.s.s of bubbles, with air inside each bubble, and the white spread out into a thin film to form the bubble walls. And the makeup of those liquid walls determines how long a foam can stand up. Pure water has such a strong surface tension - such strong attractive forces among its molecules - that it immediately starts to pull itself together into a compact puddle; and it's so runny that it puddles almost immediately. The many nonwater molecules in egg white both reduce the surface tension of the water they float in, and make it less runny, and thus allow the bubbles to survive long enough to acc.u.mulate into a sizeable ma.s.s. What gives the ma.s.s of foam a useful kitchen lifetime is the white's team of proteins.

How the Egg Proteins Stabilize Foams Stress Builds Protein Solidarity As is true for the setting of heated eggs and custards, the key to the stable egg foam is the tendency of the proteins to unfold and bond to each other when they're subjected to physical stress. In a foam this creates a kind of reinforcement for the bubble walls, the culinary equivalent of quick-setting cement. Whipping exerts two kinds of physical stress on the proteins. First, as we force the whisk through the white, the whisk wires drag some of the liquid with them, and create a pulling force that unfolds the compacted protein molecules. And second, because water and air are very different physical environments, the simple mixing of air into the whites creates an imbalance of forces that also tugs the proteins out of their usual folded shape. All these unfolded proteins (mainly the globulins and ovotransferrin) tend to gather where air and water meet, with their water-loving portions immersed in the liquid and their water-avoiding portions projecting into the air. Thus disturbed and concentrated, they readily form bonds with each other. So a continuous, solid network of proteins pervades the bubble walls, holding both water and air in place. As is true for the setting of heated eggs and custards, the key to the stable egg foam is the tendency of the proteins to unfold and bond to each other when they're subjected to physical stress. In a foam this creates a kind of reinforcement for the bubble walls, the culinary equivalent of quick-setting cement. Whipping exerts two kinds of physical stress on the proteins. First, as we force the whisk through the white, the whisk wires drag some of the liquid with them, and create a pulling force that unfolds the compacted protein molecules. And second, because water and air are very different physical environments, the simple mixing of air into the whites creates an imbalance of forces that also tugs the proteins out of their usual folded shape. All these unfolded proteins (mainly the globulins and ovotransferrin) tend to gather where air and water meet, with their water-loving portions immersed in the liquid and their water-avoiding portions projecting into the air. Thus disturbed and concentrated, they readily form bonds with each other. So a continuous, solid network of proteins pervades the bubble walls, holding both water and air in place.

Early Egg-White Foams: "Snow" and BiscuitsHow to Break Whites of Eggs SpeedilyA fig or two shred in pieces and then beaten amongst the whites of eggs will bring them into an oil speedily: some break them with a stubbed rod, and some by wringing them often through a sponge.- Sir Hugh Platt, Delightes for Ladies, Delightes for Ladies, 1605 1605Eggs in s...o...b..eak the eggs, separate the whites from the yolks, place the eggs on a plate with some b.u.t.ter, season them with salt, place on hot coals. Beat and whip the whites well, and just before serving throw them on the yolks with a drop of rosewater, the fire iron underneath: sugar, then serve.Another way: You may put the yolks in the middle of the snow that is made with your whipped whites, and then cook them before the fire on a plate.- Francois Pierre de La Varenne, Le Cuisinier francois, Le Cuisinier francois, 1651 1651To Make Italian BisketsTake a quarter of a pound of sea.r.s.ed [sieved] Sugar, and beat it in an Alabaster Mortar with the white of an Egg, and a little Gum Dragon [gum tragacanth] steept in Rose water to bring it to a perfect Paste, then mould it up with a little Anniseed and a grain of Musk; then make it up like Dutch bread, and bake it on a Pye-plate in a warm Oven, till they rise somewhat high and white, take them out, but handle them not till they be throughly dry and cold.- Queen's Closet Open'd, Queen's Closet Open'd, 1655 1655 Permanent Reinforcement A raw egg-white foam will eventually coa.r.s.en, settle, and separate. It must therefore be reinforced when it is turned into a final dish. This may be done by adding other thickening ingredients - such things as flour, cornstarch, chocolate, or gelatin. But if the foam is to be used relatively pure, as in a meringue or a flourless souffle, the egg proteins have to do the job themselves. With the help of heat, they do beautifully. A raw egg-white foam will eventually coa.r.s.en, settle, and separate. It must therefore be reinforced when it is turned into a final dish. This may be done by adding other thickening ingredients - such things as flour, cornstarch, chocolate, or gelatin. But if the foam is to be used relatively pure, as in a meringue or a flourless souffle, the egg proteins have to do the job themselves. With the help of heat, they do beautifully.

Ovalb.u.min, the major protein in egg white, is relatively immune to beating and doesn't contribute much to the raw foam. But it is sensitive to heat, which causes it to unfold and coagulate. So when the raw foam is cooked, ovalb.u.min more than doubles the amount of solid protein reinforcement in the bubble walls. At the same time, much of the free water in the foam evaporates. Heat thus allows the cook to transform a transient semi-liquid foam into a permanent solid one.

How Proteins Destabilize Destabilize Foams Foams The very same forces that make egg foams also break egg foams. Often just as the foam is reaching its optimum texture, it will get grainy, lose volume, and separate into a dry froth and a runny liquid. As the proteins bond to each other to support the foam, they embrace each other too tightly, and squeeze out the water they had held between them. There are several different kinds of bonds by which the long, unfolding egg proteins are joined to each other in a reinforcing network: bonds between positively and negatively charged parts of molecules, between water-like parts, between fat-like parts, and between sulfur groups. The protein network begins to collapse when too many of these bonds acc.u.mulate and the proteins cl.u.s.ter together too tightly. Fortunately, there are simple ways for the cook to limit the acc.u.mulation of bonds and prevent the collapse of alb.u.men foams.

Blocking Sulfur Bonds with Copper Bowls... Long before anyone knew about egg proteins or their chemical bonds, cooks had come up with a way of controlling them. The French tradition has long specified the use of copper utensils for making egg foams. One early trace of this tradition is a 1771 ill.u.s.tration in the French Long before anyone knew about egg proteins or their chemical bonds, cooks had come up with a way of controlling them. The French tradition has long specified the use of copper utensils for making egg foams. One early trace of this tradition is a 1771 ill.u.s.tration in the French Encyclopedie Encyclopedie that shows a boy in a pastry kitchen working with a straw whisk and what the accompanying key identifies as "a copper bowl for beating egg whites." It turns out that along with a very few other metals, copper has the useful tendency to form extremely tight bonds with reactive sulfur groups: so tight that the sulfur is essentially prevented from reacting with anything else. So the presence of copper in foaming egg whites essentially eliminates the strongest kind of protein bond that can form, and makes it harder for the proteins to embrace each other too tightly. Sure enough, if you whip egg whites in a copper bowl - or in a gla.s.s bowl to which you've added a pinch of a powdered copper supplement from a health food store - the foam stays glossy and never develops grains. A silver-plated bowl will do the same thing. that shows a boy in a pastry kitchen working with a straw whisk and what the accompanying key identifies as "a copper bowl for beating egg whites." It turns out that along with a very few other metals, copper has the useful tendency to form extremely tight bonds with reactive sulfur groups: so tight that the sulfur is essentially prevented from reacting with anything else. So the presence of copper in foaming egg whites essentially eliminates the strongest kind of protein bond that can form, and makes it harder for the proteins to embrace each other too tightly. Sure enough, if you whip egg whites in a copper bowl - or in a gla.s.s bowl to which you've added a pinch of a powdered copper supplement from a health food store - the foam stays glossy and never develops grains. A silver-plated bowl will do the same thing.

Foamed egg whites. The folded proteins in egg white (left) (left) produce a light, long-lived foam by unfolding at the interface between liquid and air, the walls of the air bubbles. The unfolded proteins then bond to each other, and form a solid meshwork of reinforcement around the bubbles produce a light, long-lived foam by unfolding at the interface between liquid and air, the walls of the air bubbles. The unfolded proteins then bond to each other, and form a solid meshwork of reinforcement around the bubbles (right). (right).

...And Acids There are disadvantages to the traditional copper bowl: it's expensive, and a nuisance to keep clean. (Copper contamination is negligible; a cup of foam contains a tenth of our normal daily intake.) Fortunately there's a nonmetallic alternative for controlling reactive sulfur groups. The sulfur bonds form when the sulfur-hydrogen (S-H) groups on two different protein molecules shed their hydrogens and form a sulfur-sulfur (S-S) connection with each other. The addition of an acid boosts the number of free-floating hydrogen (H) ions in the egg white, which makes it much harder for the S-H groups to shed their own H, and so slows the sulfur bonding down to a crawl. A good dose is There are disadvantages to the traditional copper bowl: it's expensive, and a nuisance to keep clean. (Copper contamination is negligible; a cup of foam contains a tenth of our normal daily intake.) Fortunately there's a nonmetallic alternative for controlling reactive sulfur groups. The sulfur bonds form when the sulfur-hydrogen (S-H) groups on two different protein molecules shed their hydrogens and form a sulfur-sulfur (S-S) connection with each other. The addition of an acid boosts the number of free-floating hydrogen (H) ions in the egg white, which makes it much harder for the S-H groups to shed their own H, and so slows the sulfur bonding down to a crawl. A good dose is 1 1/8 teaspoon/0.5g cream of tartar or teaspoon/2ml lemon juice per egg white, added at the beginning of the beating. teaspoon/0.5g cream of tartar or teaspoon/2ml lemon juice per egg white, added at the beginning of the beating.

The Enemies of Egg Foams There are three enemies to the successful mounting of a foam which the cook should be careful to exclude from the bowl: egg yolk, oil or fat, and detergent. All are chemical relatives, and interfere with foaming in the same ways: by competing with the proteins for a place at the air-water interface without offering any structural reinforcement; and by interfering with the bonding of the protein molecules. Traces of these troublemakers won't absolutely prevent you from making a foam, but they'll make you work harder and longer, and the foam won't be as light or stable. Of course yolk and fat can safely be mixed with a finished foam, as happens in many recipes for souffles and egg-leavened batters.

Copper bowls and eggs in the 18th century. This is a detail of "Patissier," "Patissier," or or "The Pastry-cook," "The Pastry-cook," from the from the Encyclopedie Encyclopedie , an engraving first published in 1771. The boy at right wields what the accompanying key calls "a copper bowl for beating egg whites and mixing them with the dough from which biscuits are made." , an engraving first published in 1771. The boy at right wields what the accompanying key calls "a copper bowl for beating egg whites and mixing them with the dough from which biscuits are made."

The Effects of Other Ingredients Egg white foams are almost always made with other ingredients, and these can influence the beating process and the final consistency.

Salt Salt increases the whipping time and decreases the foam's stability. Salt crystals dissolve into positively charged sodium and negatively charged chloride ions, and these probably compete for bonding sites on the unfolded protein molecules, thereby reducing the number of protein-protein bonds and so weakening the overall structure. It's therefore best to add salt to the other components of a dish - the base of a souffle, for example - rather than to the foam itself. Salt increases the whipping time and decreases the foam's stability. Salt crystals dissolve into positively charged sodium and negatively charged chloride ions, and these probably compete for bonding sites on the unfolded protein molecules, thereby reducing the number of protein-protein bonds and so weakening the overall structure. It's therefore best to add salt to the other components of a dish - the base of a souffle, for example - rather than to the foam itself.

Sugar Sugar both hinders and helps foam making. Added early in the process, it delays foaming, and it reduces the foam's ultimate volume and lightness. The delay comes from sugar's interference with the unfolding and bonding of the proteins. And the reduction in volume and lightness is caused by the syrupy sugar-egg mixture being harder to spread into thin bubble walls. Slow foaming is a real disadvantage when the whites are whipped by hand - at standard soft-meringue levels, it doubles the work - but less so if you're using a stand mixer. Sugar both hinders and helps foam making. Added early in the process, it delays foaming, and it reduces the foam's ultimate volume and lightness. The delay comes from sugar's interference with the unfolding and bonding of the proteins. And the reduction in volume and lightness is caused by the syrupy sugar-egg mixture being harder to spread into thin bubble walls. Slow foaming is a real disadvantage when the whites are whipped by hand - at standard soft-meringue levels, it doubles the work - but less so if you're using a stand mixer.

The helpful thing about sugar is that it improves the foam's stability. By making the liquid thick and cohesive, sugar greatly slows drainage from the bubble walls and coa.r.s.ening of texture. In the oven, the dissolved sugar hangs onto the water molecules and so delays their evaporation in the high heat until after ovalb.u.min has had time to coagulate and reinforce the raw foam. And it eventually contributes reinforcement of its own in the form of fine but solid, cotton-candy-like strands of dry sugar.

Sugar is usually incorporated into the egg whites after the foam has begun to form, when many proteins are already unfolded. For some purposes, cooks will mix sugar and whites at the outset, in order to obtain a very firm, dense foam.

A Silver Bullet for the Copper TheoryWhy do copper bowls make more stable egg foams? I've wondered about this for many years. In 1984 I did some experiments with the help of Stanford University biologists, and then published a theory in the British science journal Nature Nature and in the first edition of this book. The experiments suggested that one of the alb.u.men proteins, ovotransferrin, takes up copper from the bowl surface and is thereby rendered resistant to unfolding - which could make the foam as a whole resistant to overcoagulating. That theory stood up for ten years, until one day on a whim I tried whipping egg whites in a silver-plated bowl. Ovotransferrin doesn't bind silver, so the foam should have turned grainy. It didn't. It remained light and glossy. I resumed my frothy investigations, and learned that both copper and silver do block sulfur reactions between proteins. Hence the revised edition of the copper theory outlined here. and in the first edition of this book. The experiments suggested that one of the alb.u.men proteins, ovotransferrin, takes up copper from the bowl surface and is thereby rendered resistant to unfolding - which could make the foam as a whole resistant to overcoagulating. That theory stood up for ten years, until one day on a whim I tried whipping egg whites in a silver-plated bowl. Ovotransferrin doesn't bind silver, so the foam should have turned grainy. It didn't. It remained light and glossy. I resumed my frothy investigations, and learned that both copper and silver do block sulfur reactions between proteins. Hence the revised edition of the copper theory outlined here.

Water Water is seldom called for, but in small amounts it increases the volume and lightness of the foam. Because water thins the whites, however, it's more likely that some liquid will drain from the foam. Alb.u.men diluted by 40% or more of its volume in water cannot produce a stable foam. Water is seldom called for, but in small amounts it increases the volume and lightness of the foam. Because water thins the whites, however, it's more likely that some liquid will drain from the foam. Alb.u.men diluted by 40% or more of its volume in water cannot produce a stable foam.

Basic Egg-Beating Techniques Beating egg whites into a foam is one of those techniques about which cooks and cookbooks wax stern and stringent. In fact it's not all that sensitive to details. Just about any egg and bowl and whisk can give you a good foam.

Choosing the Eggs An egg foam begins with the eggs. Old eggs at room temperature are often recommended on the grounds that the whites are thinner and therefore foam more rapidly. This is true, and An egg foam begins with the eggs. Old eggs at room temperature are often recommended on the grounds that the whites are thinner and therefore foam more rapidly. This is true, and very very fresh eggs are said to be almost impossible to foam by hand. But fresh eggs are less alkaline and so make a more stable foam; the older thin white also drains from the foam more easily, and old eggs are more likely to leave traces of yolk in the white. Cold yolks are less likely to break as you separate them from the whites, and the whipping process quickly warms cold eggs anyway. Fresh eggs right out of the refrigerator will work fine, especially if you're using an electric mixer. Egg foams can also be made with dried egg whites. Powdered egg whites are pure, pasteurized, freeze-dried egg whites. "Meringue powder" contains more sugar than egg, and includes gums to stabilize the foam. fresh eggs are said to be almost impossible to foam by hand. But fresh eggs are less alkaline and so make a more stable foam; the older thin white also drains from the foam more easily, and old eggs are more likely to leave traces of yolk in the white. Cold yolks are less likely to break as you separate them from the whites, and the whipping process quickly warms cold eggs anyway. Fresh eggs right out of the refrigerator will work fine, especially if you're using an electric mixer. Egg foams can also be made with dried egg whites. Powdered egg whites are pure, pasteurized, freeze-dried egg whites. "Meringue powder" contains more sugar than egg, and includes gums to stabilize the foam.

Bowl and Whisk The bowl in which you beat the whites should be large enough to accommodate an eightfold expansion of their volume. It's often recommended that the cook avoid making egg foams in plastic bowls, because plastics are hydrocarbon relatives of fats, and tend to retain traces of fats and soaps. While this is true, the bowl is also unlikely to release such traces into a ma.s.s of egg white. Ordinary cleaning is adequate to make a plastic bowl suitable for foaming eggs. The bowl in which you beat the whites should be large enough to accommodate an eightfold expansion of their volume. It's often recommended that the cook avoid making egg foams in plastic bowls, because plastics are hydrocarbon relatives of fats, and tend to retain traces of fats and soaps. While this is true, the bowl is also unlikely to release such traces into a ma.s.s of egg white. Ordinary cleaning is adequate to make a plastic bowl suitable for foaming eggs.

If you're beating by hand, a large "balloon whisk" aerates a greater volume of the egg whites at a time and will speed your work. If you have a choice of machines, a stand mixer whose beater both spins on its shaft and traces a curlicue path from the center to the edge of the bowl (a "hypocycloidal" or planetary motion) beats the whites more evenly and leaves less unfoamed. Less efficient beaters produce a denser texture.

Interpreting the Foam's Appearance There are various ways to judge when the foam is at its optimum, from seeing whether the foam will support the weight of a coin or an egg, to seeing how it supports itself, in soft mounds or sharply defined peaks, to seeing whether it clings to the bowl or slips along its surface, whether its surface looks glossy or dry. All these tests tell us how crowded the air bubbles are, and how much lubrication they have between them in the way of liquid from the egg white. And different dishes will define an optimum foam differently. The lightening power of an egg foam depends not just on the foam's volume, but also on how easily it can be mixed with other ingredients, and how well it can accommodate bubble expansion in the oven. Souffles and cakes require the lubrication and expansion tolerance of a somewhat underbeaten foam, while in meringues and related pastries volume is less important than shape-holding stiffness. There are various ways to judge when the foam is at its optimum, from seeing whether the foam will support the weight of a coin or an egg, to seeing how it supports itself, in soft mounds or sharply defined peaks, to seeing whether it clings to the bowl or slips along its surface, whether its surface looks glossy or dry. All these tests tell us how crowded the air bubbles are, and how much lubrication they have between them in the way of liquid from the egg white. And different dishes will define an optimum foam differently. The lightening power of an egg foam depends not just on the foam's volume, but also on how easily it can be mixed with other ingredients, and how well it can accommodate bubble expansion in the oven. Souffles and cakes require the lubrication and expansion tolerance of a somewhat underbeaten foam, while in meringues and related pastries volume is less important than shape-holding stiffness.

Glossy Soft Peaks and Stiff Peaks At the "soft peak" stage, when glossy foam edges retain some shape but droop, and when the foam doesn't yet cling to the bowl, the somewhat coa.r.s.e bubbles are still lubricated by plenty of liquid, which would quickly drain to the bottom of the bowl. At the "stiff peak" stage, where the foam is still glossy but now retains a well-defined edge and clings to the bowl, the foam is approaching 90% air, and the egg liquid has been spread so thin that the protein webs in adjacent bubble walls begin to catch on each other and on the bowl surface. There's just enough lubrication left for the foam to be creamy and easily mixed with other ingredients. This stage, or perhaps just before it, is the optimum for making mousses, souffles, sponge cakes, and similar dishes that involve mixing and further rising in the oven. Further beating gains little additional volume. At the "soft peak" stage, when glossy foam edges retain some shape but droop, and when the foam doesn't yet cling to the bowl, the somewhat coa.r.s.e bubbles are still lubricated by plenty of liquid, which would quickly drain to the bottom of the bowl. At the "stiff peak" stage, where the foam is still glossy but now retains a well-defined edge and clings to the bowl, the foam is approaching 90% air, and the egg liquid has been spread so thin that the protein webs in adjacent bubble walls begin to catch on each other and on the bowl surface. There's just enough lubrication left for the foam to be creamy and easily mixed with other ingredients. This stage, or perhaps just before it, is the optimum for making mousses, souffles, sponge cakes, and similar dishes that involve mixing and further rising in the oven. Further beating gains little additional volume.

Dry Peaks and Beyond Just past the stiff-peak stage, the foam is even firmer, takes on a dull, dry appearance and crumbly consistency, and begins to leak some liquid, so that it slips away from the bowl again. At this "slip-and-streak" stage, as pastry chef Bruce Healy describes it, the protein webs in adjacent bubble walls are bonding to each other and squeezing out what little liquid once separated them. Pastry makers look for this stage to give them the firmest foam for a meringue or cookie batter; they stop the incipient overcoagulation and weeping by immediately adding sugar, which separates the proteins and absorbs the water. They also start the beating with about half the cream of tartar per egg that a cake or souffle maker will, so that the foam will in fact progress to this somewhat overwhipped condition. Past the slip-and-streak stage, the foam begins to lose volume and get grainy. Just past the stiff-peak stage, the foam is even firmer, takes on a dull, dry appearance and crumbly consistency, and begins to leak some liquid, so that it slips away from the bowl again. At this "slip-and-streak" stage, as pastry chef Bruce Healy describes it, the protein webs in adjacent bubble walls are bonding to each other and squeezing out what little liquid once separated them. Pastry makers look for this stage to give them the firmest foam for a meringue or cookie batter; they stop the incipient overcoagulation and weeping by immediately adding sugar, which separates the proteins and absorbs the water. They also start the beating with about half the cream of tartar per egg that a cake or souffle maker will, so that the foam will in fact progress to this somewhat overwhipped condition. Past the slip-and-streak stage, the foam begins to lose volume and get grainy.

Egg foams can be used on their own or as the aerating ingredient in a variety of complicated mixtures.

Meringues: Sweet Foams on Their Own Though they're sometimes folded into cake or cookie batters or fillings, meringues - sweetened egg foams - generally stand by themselves as a discrete element in a dish: as a frothy topping, for example, or a creamy icing, or a hard edible container, or melt-in-the-mouth decoration. A meringue foam must therefore be stiff and stable enough to hold its shape. The cook obtains both stiffness and stability by the addition of sugar and/or of heat. Meringues are often baked very slowly in a low oven (200F/93C) to dry them out into a brittle, pristinely white morsel or container. (The door of electric ovens should be left slightly ajar to allow the meringue's moisture to escape; gas ovens are already vented.) When quickly browned in a hot oven or under the broiler - atop a pie, for example - the surface gets crisp while the interior remains moist. Poached in milk for the dish called Floating Islands, they are firm yet moist throughout.

Sugar in Meringues The addition of sugar is what makes a fragile egg-white foam into a stable, glossy meringue. The more sugar added, the more body the meringue will have, and the crisper it will be when baked. The proportion (by either volume or weight) of sugar to egg white ranges from about 1 to 1 to about 2 to 1, the equivalent of a 50% and a 67% sugar solution, respectively. The higher is typical of jams and jellies - and also the room-temperature limit of sugar's solubility in water. Ordinary granulated sugar won't dissolve completely in a "hard" meringue, and will leave a gritty texture and weeping syrup drops. Superfine and powdered "confectioner's" sugar, or a premade syrup, are better choices. (Powdered sugar, which weighs half as much as the other sugars cup for cup, contains 10% cornstarch to help prevent caking, which some cooks dislike and others value as moisture-absorbing insurance.) The addition of sugar is what makes a fragile egg-white foam into a stable, glossy meringue. The more sugar added, the more body the meringue will have, and the crisper it will be when baked. The proportion (by either volume or weight) of sugar to egg white ranges from about 1 to 1 to about 2 to 1, the equivalent of a 50% and a 67% sugar solution, respectively. The higher is typical of jams and jellies - and also the room-temperature limit of sugar's solubility in water. Ordinary granulated sugar won't dissolve completely in a "hard" meringue, and will leave a gritty texture and weeping syrup drops. Superfine and powdered "confectioner's" sugar, or a premade syrup, are better choices. (Powdered sugar, which weighs half as much as the other sugars cup for cup, contains 10% cornstarch to help prevent caking, which some cooks dislike and others value as moisture-absorbing insurance.) Meringue Types The traditional meringue terminology - French, Italian, Swiss, and so on - is unclear and used inconsistently. These foams are best cla.s.sified according to the method of preparation and resulting texture. Meringues can be either The traditional meringue terminology - French, Italian, Swiss, and so on - is unclear and used inconsistently. These foams are best cla.s.sified according to the method of preparation and resulting texture. Meringues can be either uncooked uncooked or or cooked. cooked. If the sugar is added after the egg whites have been whipped on their own, the meringue will be relatively If the sugar is added after the egg whites have been whipped on their own, the meringue will be relatively light light; if the sugar is added early in the whipping, the meringue will be relatively dense. dense.

Uncooked Meringues Uncooked meringues are the simplest and most common, and provide a broad range of textures, from frothy to creamy to dense and stiff. The lightest possible consistency is obtained by first beating the whites to a firm foam and then gently folding in the sugar with a spatula. The sugar dissolves into the existing bubble walls and adds both bulk and cohesiveness to them. The added bulk gives the bubbles more room to slide past each other and creates a soft, frothy consistency suitable for a spread pie topping or for folding into a mousse or chiffon mix, but too fragile to shape. A creamier, firmer consistency results when the sugar is not merely folded in, but beaten in. In this case, the sugar's added bulk is spread out as the beating further subdivides the bubbles, and the cohesiveness of the sugar-water mixture noticeably tightens the foam's texture. The longer you beat the egg-sugar mixture, the stiffer it will get and the more finely it can be shaped. Uncooked meringues are the simplest and most common, and provide a broad range of textures, from frothy to creamy to dense and stiff. The lightest possible consistency is obtained by first beating the whites to a firm foam and then gently folding in the sugar with a spatula. The sugar dissolves into the existing bubble walls and adds both bulk and cohesiveness to them. The added bulk gives the bubbles more room to slide past each other and creates a soft, frothy consistency suitable for a spread pie topping or for folding into a mousse or chiffon mix, but too fragile to shape. A creamier, firmer consistency results when the sugar is not merely folded in, but beaten in. In this case, the sugar's added bulk is spread out as the beating further subdivides the bubbles, and the cohesiveness of the sugar-water mixture noticeably tightens the foam's texture. The longer you beat the egg-sugar mixture, the stiffer it will get and the more finely it can be shaped.

These standard methods take only a few minutes but require the cook's attention. Some professionals, particularly in France, make firm meringues suitable for the pastry pipe on the kitchen equivalent of autopilot. They place all the sugar in the bowl of a stand mixer, add a portion of the egg whites with some lemon juice to prevent graining, mix for several minutes - the timing is not critical - then add more whites, mix a while, and so on. The result is a fine-textured, stiff, supple meringue. Beating the eggs gradually into the sugar rather than the other way around does slow the foaming, but requires little supervision. Such "automatic" meringues are denser than usual and less brittle when dried down.

Food Words: Meringue MeringueThanks to the Larousse Gastronomique, Larousse Gastronomique, it's widely believed that the meringue was invented by a pastry chef in the Swiss town of Mieringen around 1720, and brought to France a couple of decades later by the Polish father-in-law of Louis XV. Sounds suitably colorful: except that the French writer Ma.s.sialot had already published a recipe for "Meringues" in 1691. it's widely believed that the meringue was invented by a pastry chef in the Swiss town of Mieringen around 1720, and brought to France a couple of decades later by the Polish father-in-law of Louis XV. Sounds suitably colorful: except that the French writer Ma.s.sialot had already published a recipe for "Meringues" in 1691.The linguist Otto Janicke has traced the word meringue meringue back to an alteration of the Latin word back to an alteration of the Latin word merenda, merenda, meaning "light evening meal," into meaning "light evening meal," into meringa, meringa, a form that was found in the Artois and Picardie near what is now Belgium. Janicke cites many variations on a form that was found in the Artois and Picardie near what is now Belgium. Janicke cites many variations on merenda merenda that variously meant "evening bread," "shepherd's loaf," "food taken to the field and forest," "traveler's snack." that variously meant "evening bread," "shepherd's loaf," "food taken to the field and forest," "traveler's snack."What do breads and road food have to do with whipped egg whites? Early baked sugar-egg pastes were called "biscuits," "breads," and "loaves" because they were miniature imitations of these baked goods (biscuits, being thoroughly dried and therefore light and durable, were standard traveler's fare). Perhaps such a confection was called meringa meringa in northeast France. Then, when cooks from that region discovered the advantage of beating the eggs thoroughly with the new straw whisk before adding sugar, the local term spread with their invention, and in the rest of France served to distinguish this delicate foam from its dense predecessors. in northeast France. Then, when cooks from that region discovered the advantage of beating the eggs thoroughly with the new straw whisk before adding sugar, the local term spread with their invention, and in the rest of France served to distinguish this delicate foam from its dense predecessors.

Between the two extremes - adding all the sugar after the foam has been