On Food And Cooking Part 3

India's Galaxy of Cooked MilksFor sheer inventiveness with milk itself as the primary ingredient, no country on earth can match India. Its dozens of variations on the theme of cooked-down milk, many of them dating back a thousand years, stem from a simple fact of life in that warm country: the simplest way to keep milk from souring is to boil it repeatedly. Eventually it cooks down to a brown, solid paste with about 10% moisture, 25% lactose, 20% protein and 20% b.u.t.terfat. Even without added sugar, khoa khoa is almost a candy, so it makes sense that over time, it and the intermediate concentrations that precede it became the basis for the most widely made Indian milk sweets. Doughnut-like fried is almost a candy, so it makes sense that over time, it and the intermediate concentrations that precede it became the basis for the most widely made Indian milk sweets. Doughnut-like fried gulabjamun gulabjamun and fudge-like and fudge-like burfi burfi are rich in lactose, calcium, and protein: a gla.s.s of milk distilled into a morsel. are rich in lactose, calcium, and protein: a gla.s.s of milk distilled into a morsel.A second, separate constellation of Indian milk sweets is based on concentrating the milk solids by curdling them with heat and either lime juice or sour whey. The drained curds form a soft, moist ma.s.s known as chhanna, chhanna, which then becomes the base for a broad range of sweets, notably porous, springy cakes soaked in sweetened milk or syrup ( which then becomes the base for a broad range of sweets, notably porous, springy cakes soaked in sweetened milk or syrup (rasmalai, rasagollah).

Espresso Steamers: Simultaneous Bubbles and Heat Milk foams are usually made with the help of the steam nozzle on an espresso coffee machine. Steaming milk accomplishes two essential things simultaneously: it introduces bubbles into the milk, and it heats the bubbles enough to unfold and coagulate the whey proteins into a stabilizing web. Steam itself does not make bubbles: it is water vapor, and simply condenses into the colder water of the milk. Steam makes bubbles by splas.h.i.+ng milk and air together, and it does this most efficiently when the nozzle is just below the milk surface. Milk foams are usually made with the help of the steam nozzle on an espresso coffee machine. Steaming milk accomplishes two essential things simultaneously: it introduces bubbles into the milk, and it heats the bubbles enough to unfold and coagulate the whey proteins into a stabilizing web. Steam itself does not make bubbles: it is water vapor, and simply condenses into the colder water of the milk. Steam makes bubbles by splas.h.i.+ng milk and air together, and it does this most efficiently when the nozzle is just below the milk surface.

One factor that makes steaming tricky is that very hot milk doesn't hold its foam well. A foam collapses when gravity pulls the liquid out of the bubble walls, and the hotter the liquid, the faster it drains. So you have to use a large enough volume of cold milk - at least 2 2/3 cup/150 ml - to make sure that the milk doesn't heat up too fast and become too runny before the foam forms. cup/150 ml - to make sure that the milk doesn't heat up too fast and become too runny before the foam forms.

Cream Cream is a special portion of milk that is greatly enriched with fat. This enrichment occurs naturally thanks to the force of gravity, which exerts more of a pull on the milk's water than on the less dense fat globules. Leave a container of milk fresh from the udder to stand undisturbed, and the globules slowly rise through the water and crowd together at the top. The concentrated cream layer can then be skimmed off from the fat-depleted "skim" milk below. Milk with 3.5% fat will naturally yield cream that is about 20%.

We value cream above all for its feel. Creaminess Creaminess is a remarkable consistency, perfectly balanced between solidity and fluidity, between persistence and evanescence. It's substantial, yet smooth and seamless. It lingers in the mouth, yet offers no resistance to teeth or tongue, nor becomes merely greasy. This luxurious sensation results from the crowding of the fat globules, which are far too small for our senses to distinguish, into a small volume of water, whose free movement is thus impeded and slowed. is a remarkable consistency, perfectly balanced between solidity and fluidity, between persistence and evanescence. It's substantial, yet smooth and seamless. It lingers in the mouth, yet offers no resistance to teeth or tongue, nor becomes merely greasy. This luxurious sensation results from the crowding of the fat globules, which are far too small for our senses to distinguish, into a small volume of water, whose free movement is thus impeded and slowed.

Keys to Foaming MilkTo get a good volume of milk foam from the steam attachment on an espresso machine: Use fresh milk right out of the refrigerator, or even chilled for a few minutes in the freezer.

Start with at least 2 2/3 cup/150 ml of milk in a container that will hold at least double the initial volume. cup/150 ml of milk in a container that will hold at least double the initial volume.

Keep the nozzle at or just under the milk surface so that it froths continuously with a moderate flow of steam.

To foam a small volume of milk without steam, separate the foaming and heating steps: Pour cold, fresh milk into a jar, tighten the lid, and shake it vigorously for 20 seconds or until the contents have doubled in volume. (Or froth in a plunger-style coffee maker, whose fine screen produces an especially thick, creamy foam.) Then stabilize the foam: remove the lid, place the jar in the microwave, and heat on high for about 30 seconds, or until the foam rises to the top of the jar.

In addition to its appealing texture, cream has distinctive "fatty" aroma notes from molecules also found in coconut and peach (lactones). And it offers the virtue of being a robust, forgiving ingredient. Milk contains roughly equal weights of protein and fat, while in cream fat outweighs protein by at least 10 to 1. Thanks to this dilution of the protein, cream is less likely to curdle. And thanks to its concentration of fat globules, it can be inflated into whipped cream: a far more substantial and stable foam than milk alone can make.

Though it has certainly been appreciated since the beginning of dairying, cream spoils faster than the b.u.t.ter that could be made from it, and so it played a minor role in all but farmhouse kitchens until fairly recently. By the 17th century, French and English cooks were frothing cream into imitation snow; the English exploited its layering nature to pile cream skins in the form of a cabbage, and used long, gentle heating to produce solid, nutty "clouted" cream. Cream's heyday arrived in the 18th century, when it went into cakes, puddings, and such savory dishes as frica.s.sees, stews, and boiled vegetables, and became popular in frozen form as ice cream. The popularity of cream declined in the 20th century with the nutritional condemnation of saturated fats, so much so that in many parts of the United States it's only available in the long-keeping ultrapasteurized form.

Making Cream The natural separation of cream from milk by means of gravity takes 12 to 24 hours, and was superseded late in the 19th century by the merry-go-round forces of the French centrifugal separator. Once separated, the cream is pasteurized. In the United States, the minimum temperatures for pasteurizing cream are higher than the milk minimum (for 20% fat or less, 30 minutes at 155F/68C; otherwise at 165F/74C). "Ultrapasteurized" cream is heated for 2 seconds at 280F/140C (like UHT-treated milk, p. 22; however the cream is not packaged under strictly sterile conditions, and so is kept refrigerated). Under refrigeration, ordinary pasteurized cream keeps for about 15 days before bacterial activity turns it bitter and rancid; ultrapasteurized cream, which has a stronger cooked flavor, keeps for several weeks. Normally cream is not h.o.m.ogenized because this makes it harder to whip, but long-keeping ultrapasteurized cream and relatively thin half-and-half are usually h.o.m.ogenized to prevent continuing slow separation in the carton. The natural separation of cream from milk by means of gravity takes 12 to 24 hours, and was superseded late in the 19th century by the merry-go-round forces of the French centrifugal separator. Once separated, the cream is pasteurized. In the United States, the minimum temperatures for pasteurizing cream are higher than the milk minimum (for 20% fat or less, 30 minutes at 155F/68C; otherwise at 165F/74C). "Ultrapasteurized" cream is heated for 2 seconds at 280F/140C (like UHT-treated milk, p. 22; however the cream is not packaged under strictly sterile conditions, and so is kept refrigerated). Under refrigeration, ordinary pasteurized cream keeps for about 15 days before bacterial activity turns it bitter and rancid; ultrapasteurized cream, which has a stronger cooked flavor, keeps for several weeks. Normally cream is not h.o.m.ogenized because this makes it harder to whip, but long-keeping ultrapasteurized cream and relatively thin half-and-half are usually h.o.m.ogenized to prevent continuing slow separation in the carton.

The Importance of Fat Content Cream is manufactured with a number of different fat levels and consistencies, each for particular purposes. Light creams are poured into coffee or onto fruit; heavy creams are whipped or used to thicken sauces; clotted or "plastic" creams are spread onto breads, pastries, or fruit. The proportion of fat determines both a cream's consistency and its versatility. Heavy cream can be diluted with milk to approximate light cream, or whipped to make a spreadable semisolid. Light cream and half-and-half contain insufficient numbers of fat globules to stabilize a whipped foam (p. 32), or to resist curdling in a sauce. Whipping cream, at between 30 and 40% fat, is the most versatile formulation. Cream is manufactured with a number of different fat levels and consistencies, each for particular purposes. Light creams are poured into coffee or onto fruit; heavy creams are whipped or used to thicken sauces; clotted or "plastic" creams are spread onto breads, pastries, or fruit. The proportion of fat determines both a cream's consistency and its versatility. Heavy cream can be diluted with milk to approximate light cream, or whipped to make a spreadable semisolid. Light cream and half-and-half contain insufficient numbers of fat globules to stabilize a whipped foam (p. 32), or to resist curdling in a sauce. Whipping cream, at between 30 and 40% fat, is the most versatile formulation.

Fat globules in milk and cream. Left to right: Left to right: Fat globules in h.o.m.ogenized milk (3.5% fat), and in unh.o.m.ogenized light cream (20% fat), and in heavy cream (40% fat). The more numerous fat globules in cream interfere with the flow of the surrounding fluid and give cream its full-bodied consistency. Fat globules in h.o.m.ogenized milk (3.5% fat), and in unh.o.m.ogenized light cream (20% fat), and in heavy cream (40% fat). The more numerous fat globules in cream interfere with the flow of the surrounding fluid and give cream its full-bodied consistency.

Stability in Cooking How does a high fat content permit the cook to boil a mixture of heavy cream and salty or acidic ingredients without curdling it, as when dissolving pan solids or thickening a sauce? The key seems to be the ability of the fat globule's surface membrane to latch onto a certain amount of the major milk protein, casein, when milk is heated. If the fat globules account for 25% or more of the cream's weight, then there's a sufficient area of globule surface to take most of the casein out of circulation, and no casein curds can form. At lower fat levels, there's both a smaller globule surface area How does a high fat content permit the cook to boil a mixture of heavy cream and salty or acidic ingredients without curdling it, as when dissolving pan solids or thickening a sauce? The key seems to be the ability of the fat globule's surface membrane to latch onto a certain amount of the major milk protein, casein, when milk is heated. If the fat globules account for 25% or more of the cream's weight, then there's a sufficient area of globule surface to take most of the casein out of circulation, and no casein curds can form. At lower fat levels, there's both a smaller globule surface area and and a greater proportion of the casein-carrying water phase. Now the globule surfaces can only absorb a small fraction of the casein, and the rest bonds together and coagulates when heated. (This is why acid-curdled mascarpone cheese can be made from light cream, but not from heavy cream.) a greater proportion of the casein-carrying water phase. Now the globule surfaces can only absorb a small fraction of the casein, and the rest bonds together and coagulates when heated. (This is why acid-curdled mascarpone cheese can be made from light cream, but not from heavy cream.) Kinds of Cream

U.S. Term Fat Content, % Fat Content, % Use Use

Half-and-half 12 (10.518) 12 (10.518) Coffee, pouring Coffee, pouring

1230 Coffee, pouring, enriching sauces, soups, etc., whipping Coffee, pouring, enriching sauces, soups, etc., whipping

18+.

Coffee, pouring Coffee, pouring

Light cream 20 (1830) 20 (1830) Coffee, pouring (seldom available) Coffee, pouring (seldom available)

25.

Coffee, pouring Coffee, pouring

Light whipping cream 3036 3036 Pouring, enriching, whipping Pouring, enriching, whipping

3040 Pouring, enriching, whipping (if rich, spreading) Pouring, enriching, whipping (if rich, spreading)

Whipping cream 35+ 35+.

Pouring, enriching, whipping Pouring, enriching, whipping

Heavy whipping cream 38 (36+) 38 (36+).

Pouring, enriching, whipping Pouring, enriching, whipping

48+.

Spreading Spreading

55+.

Spreading Spreading

Plastic cream 6585 6585 Spreading Spreading

European Term Fat Content, % Fat Content, % Use Use

12 (10.518) Coffee, pouring Coffee, pouring

Creme legere*

1230 1230 Coffee, pouring, enriching sauces, soups, etc., whipping Coffee, pouring, enriching sauces, soups, etc., whipping

Single cream 18+ 18+.

Coffee, pouring Coffee, pouring

20 (1830) Coffee, pouring (seldom available) Coffee, pouring (seldom available)

Coffee cream 25 25.

Coffee, pouring Coffee, pouring

3036 Pouring, enriching, whipping (if rich, spreading) Pouring, enriching, whipping (if rich, spreading)

Creme fraiche** (fleurette or or epaisse epaisse) * *

3040 3040 Pouring, enriching, whipping Pouring, enriching, whipping

35+.

Pouring, enriching, whipping Pouring, enriching, whipping

38 (36+).

Pouring, enriching, whipping Pouring, enriching, whipping

Double cream 48+ 48+.

Spreading Spreading

Clotted cream 55+ 55+.

Spreading Spreading

6585 Spreading Spreading

* *legere: "light"; fleurette fleurette: "liquid"; epaisse epaisse: "thick" due to bacterial culture**fraiche: "fresh, cool, new." In France, creme fraiche creme fraiche may be either "sweet" or cultured with lactic acid bacteria; in the United States, the term always means cultured, tart, thick cream. See p. 49. may be either "sweet" or cultured with lactic acid bacteria; in the United States, the term always means cultured, tart, thick cream. See p. 49.

Problems with Cream: Separation A common problem with unh.o.m.ogenized cream is that it continues to separate in the carton: the fat globules slowly rise and concentrate further into a semisolid layer at the top. At refrigerator temperatures, the fat inside the globules forms solid crystals whose edges break through the protective globule membrane, and these slightly protruding fat crystals get stuck to each other and form microscopic b.u.t.ter grains. A common problem with unh.o.m.ogenized cream is that it continues to separate in the carton: the fat globules slowly rise and concentrate further into a semisolid layer at the top. At refrigerator temperatures, the fat inside the globules forms solid crystals whose edges break through the protective globule membrane, and these slightly protruding fat crystals get stuck to each other and form microscopic b.u.t.ter grains.

Clotted Creams These days cooks generally consider the separation and solidification of cream a nuisance. In the past, and in present-day England and the Middle East, congealed cream has been and is appreciated for its own sake. The cooks of 17th century England would patiently lift the skins from shallow dishes of cream and arrange them in wrinkled mounds to imitate the appearance of a cabbage. Cabbage cream is now a mere curiosity. But the 16th century English invention called These days cooks generally consider the separation and solidification of cream a nuisance. In the past, and in present-day England and the Middle East, congealed cream has been and is appreciated for its own sake. The cooks of 17th century England would patiently lift the skins from shallow dishes of cream and arrange them in wrinkled mounds to imitate the appearance of a cabbage. Cabbage cream is now a mere curiosity. But the 16th century English invention called clotted clotted cream (and its Turkish and Afghan relatives cream (and its Turkish and Afghan relatives kaymak kaymak and and qymaq qymaq) remain vital traditions.

Old-fas.h.i.+oned clotted cream is made by heating cream just short of the boil in shallow pans for several hours, then letting it cool and stand for a day or so, and removing the thick solid layer. Heat accelerates the rise of the fat globules, evaporates some of the water, melts some of the aggregated globules into pockets of b.u.t.terfat, and creates a cooked flavor. The result is a mix of thick, granular, fatty areas and thin, creamy ones, with a rich, nutty flavor and a straw-colored surface. Clotted cream is around 60% fat, and is spread onto scones and biscuits and eaten with fruit.