On Food And Cooking Part 63

8 8.

72 72.

15 15.

Peanut 6 6.

26 26.

48 48.

19 19.

Pecan 5 5.

8 8.

68 68.

18 18.

Pine nut 6 6.

31 31.

47 47.

12 12.

Pistachio 5 5.

20 20.

54 54.

19 19.

Poppy seed 7 7.

18 18.

45 45.

24 24.

Sesame seed 5 5.

18 18.

50 50.

24 24.

Sunflower 5 5.

24 24.

47 47.

20 20.

Walnut, black 3 3.

21 21.

59 59.

15 15.

Walnut, English 4 4.

15 15.

64 64.

16 16.

Nut Flavor Nuts provide us with a distinctive, appealing, and versatile set of flavors. Nuttiness is a cl.u.s.ter of qualities: slightly sweet, slightly fatty, slightly roasted or toasted; a delicate flavor, yet with some depth. The nuts' ample endowment of oil is key to their character; the less rich grains take on a pleasant flavor when simply toasted dry, but develop an added dimension when cooked in oil or fat. The quality of nuttiness complements many other foods, whether savory or sweet, all the way from fish to chocolate.

Most nuts contain at least traces of free sugars. Some contain more than a trace and are noticeably sweet; these include chestnuts, cashews, pistachios, and pine nuts.

Handling and Storing Nuts The same high oil content that makes nuts nutritious and delicious also makes them much more fragile than grains and legumes: that oil readily absorbs odors from the surroundings, and goes rancid when it's split into its component fatty acids and the fatty acids are then fragmented by oxygen and light. The fatty acids have an irritating effect on the mouth, while their fragments have cardboard, paint-like aromas. Walnuts, pecans, cashews, and peanuts are rich in fragile polyunsaturated fats and are especially susceptible to staling. Fat rancidity is favored by bruising, light, heat, and moisture, so it's best to store nuts in opaque containers at cool temperatures. Sh.e.l.l-less kernels are best refrigerated. Because they contain very little water and so don't suffer from the formation of damaging ice crystals, nuts can be frozen for long keeping. Storage containers should be truly air-and odor-tight - gla.s.s jars, for example, rather than permeable plastic bags.

Nuts are at their best when they're freshly harvested, usually in late summer and fall (early summer for almonds). Newly harvested nuts are too moist to keep without being vulnerable to molds, so producers dry them with as little heat as possible, usually at 90100F/3238C. When buying fresh nuts, look for an opaque, off-white interior. Any translucency or darkening is a sign that the cells are damaged, oil has been released, and rancidity is developing.

Cooking Nuts Unlike most other seed foods, nuts are good simply oven-toasted or fried for a few minutes, which transforms the chewy, pliable, bland, pale seeds into crisp, flavorful, browned morsels. They can also be roasted in the microwave oven. Since nuts are small and dry, frying is generally done at relatively low temperatures for relatively short times, 250350F/120175C for a few minutes, with lower temperatures and longer times for large nuts (Brazil nuts, macadamias). Doneness should be judged by color and flavor, not texture; heat softens the tissue, which gets crisp as it cools. Stop the cooking just short of the ideal doneness, since nuts continue to cook for some time after they're taken from the heat. Nuts are less brittle when they're warm, so slicing them while warm can give cleaner pieces with fewer flakes and crumbs.

Commercially prepared nuts are often roasted, salted with special flake-shaped particles that have more of a surface to adhere to the nut, then coated with a layer of oil or a protein-emulsifier blend to help retain the salt. Peanuts are salted in the sh.e.l.l by being soaked in brine under a vacuum, which pulls the air from inside the sh.e.l.l and forces the brine in.

Removing Skins Many preparations call for nut skins to be removed so that they don't discolor the dish or add unwanted astringency. Thin skins - those on peanuts and hazelnuts, for example - can often be made brittle enough to rub off by a brief toasting in the oven. The thicker skins of almonds are toughened and loosened by a minute or two in boiling water. Others can often be removed by immersing the nuts in hot water made alkaline with baking soda (3 Tb soda per quart/45 gm per liter), rubbing the softened skins off (alkalinity helps dissolve hemicellulose cement in the cell walls), then reimmersing the nuts in a dilute acid solution to neutralize the slight amount of absorbed alkaline liquid. The color and astringency of hard-to-remove walnut skins can be lightened significantly by a brief boiling in acidified water, which leaches out tannins and bleaches the color of those that remain. Tough chestnut skins are softened by roasting or boiling in the sh.e.l.l, or by a brief period in the microwave oven. They're also simply peeled off like the skin of an apple. Many preparations call for nut skins to be removed so that they don't discolor the dish or add unwanted astringency. Thin skins - those on peanuts and hazelnuts, for example - can often be made brittle enough to rub off by a brief toasting in the oven. The thicker skins of almonds are toughened and loosened by a minute or two in boiling water. Others can often be removed by immersing the nuts in hot water made alkaline with baking soda (3 Tb soda per quart/45 gm per liter), rubbing the softened skins off (alkalinity helps dissolve hemicellulose cement in the cell walls), then reimmersing the nuts in a dilute acid solution to neutralize the slight amount of absorbed alkaline liquid. The color and astringency of hard-to-remove walnut skins can be lightened significantly by a brief boiling in acidified water, which leaches out tannins and bleaches the color of those that remain. Tough chestnut skins are softened by roasting or boiling in the sh.e.l.l, or by a brief period in the microwave oven. They're also simply peeled off like the skin of an apple.

Nut Pastes and b.u.t.ters All dry and fatty nuts can be ground in a mortar or blender into a b.u.t.ter-like paste, with the oil from ruptured cells coating and lubricating the cell fragments and particles of intact cells. One of the most venerable nut pastes is the Middle Eastern tahini, made from ground sesame seeds; it's used with chickpeas to make hummus, and with eggplant to make baba ghanoush. Throughout the world, nut pastes are added to soups and stews to contribute flavor, richness, and body; almond soups are made in Spain and Turkey, walnut soups in Mexico, coconut soups in Brazil, pecan and peanut soups in the American South. All dry and fatty nuts can be ground in a mortar or blender into a b.u.t.ter-like paste, with the oil from ruptured cells coating and lubricating the cell fragments and particles of intact cells. One of the most venerable nut pastes is the Middle Eastern tahini, made from ground sesame seeds; it's used with chickpeas to make hummus, and with eggplant to make baba ghanoush. Throughout the world, nut pastes are added to soups and stews to contribute flavor, richness, and body; almond soups are made in Spain and Turkey, walnut soups in Mexico, coconut soups in Brazil, pecan and peanut soups in the American South.

Nut Oils The oils of a number of nuts are prized for their flavor - walnut oil and coconut oil, for example - and several others as ordinary cooking oils (peanut oil, sunflower seed oil). Oils are extracted from nuts by two different means. "Cold-pressed" or "expeller-pressed" nut oils are made by crus.h.i.+ng the nut cells and forcing the oil out with mechanical pressure. The nuts get hot from the pressure and friction, but generally don't exceed the boiling point. Solvent-extracted oils are made by dissolving the oil out of the crushed nuts with a solvent at temperatures around 300F/150C, then separating the oil from the solvent. They are more refined than pressed oils, having fewer of the trace compounds that make oils both flavorful and potentially allergenic (p. 455). Cold-pressed oils are generally used as a flavoring, refined oils as cooking oils. Nut oils have a stronger flavor if the nuts are roasted before extraction. Because they often have a large proportion of fragile polyunsaturated fatty acids, they're more vulnerable to oxidation than ordinary vegetable oils, and are best kept in dark bottles in the refrigerator. The leftover solids - nut meal or flour - make a flavorful and nutritious contribution to baked goods. The oils of a number of nuts are prized for their flavor - walnut oil and coconut oil, for example - and several others as ordinary cooking oils (peanut oil, sunflower seed oil). Oils are extracted from nuts by two different means. "Cold-pressed" or "expeller-pressed" nut oils are made by crus.h.i.+ng the nut cells and forcing the oil out with mechanical pressure. The nuts get hot from the pressure and friction, but generally don't exceed the boiling point. Solvent-extracted oils are made by dissolving the oil out of the crushed nuts with a solvent at temperatures around 300F/150C, then separating the oil from the solvent. They are more refined than pressed oils, having fewer of the trace compounds that make oils both flavorful and potentially allergenic (p. 455). Cold-pressed oils are generally used as a flavoring, refined oils as cooking oils. Nut oils have a stronger flavor if the nuts are roasted before extraction. Because they often have a large proportion of fragile polyunsaturated fatty acids, they're more vulnerable to oxidation than ordinary vegetable oils, and are best kept in dark bottles in the refrigerator. The leftover solids - nut meal or flour - make a flavorful and nutritious contribution to baked goods.

Nut Milks If nuts are ground while dry, their microscopic oil bodies (p. 459) merge and coalesce to make oil the continuous liquid phase of the paste. But if the raw nuts are first soaked in water, then grinding releases the oil bodies relatively intact into the continuous water phase. When the solid nut particles are strained off, this leaves behind a fluid similar to milk, with oil droplets, proteins, sugars, and salts dispersed in water. In medieval Europe, which learned about them from the Arabs, almond milks and creams were both luxurious ingredients and dairy subst.i.tutes for fasting days. Today, the most common seed milk is made from coconuts, but it can be made from any oil-rich nut and from soybeans (p. 494). If nuts are ground while dry, their microscopic oil bodies (p. 459) merge and coalesce to make oil the continuous liquid phase of the paste. But if the raw nuts are first soaked in water, then grinding releases the oil bodies relatively intact into the continuous water phase. When the solid nut particles are strained off, this leaves behind a fluid similar to milk, with oil droplets, proteins, sugars, and salts dispersed in water. In medieval Europe, which learned about them from the Arabs, almond milks and creams were both luxurious ingredients and dairy subst.i.tutes for fasting days. Today, the most common seed milk is made from coconuts, but it can be made from any oil-rich nut and from soybeans (p. 494).

Argan OilAn unusual nut known in the West almost exclusively for its oil is argan, the seed of a drought-tolerant tree native to Morocco (Argania spinosa, a relative of the chicle and miracle fruit trees). The almond-like nuts are removed from their fruits (a process formerly a.s.signed to goats, which eat the fruits and excrete the nuts), sh.e.l.led and roasted, then ground and pressed. Argan oil has a distinctive, almost meaty aroma. a relative of the chicle and miracle fruit trees). The almond-like nuts are removed from their fruits (a process formerly a.s.signed to goats, which eat the fruits and excrete the nuts), sh.e.l.led and roasted, then ground and pressed. Argan oil has a distinctive, almost meaty aroma.

Modern cooks can use nut milks to make rich and delicious ices, and to enrich sauces and soups. Thanks to the tendency of the nut proteins to coagulate, cooks can thicken nut milks with acid into the equivalent of yogurt, and cook them into a cross between a pudding and custard. Almonds with their high protein content produce the most easily thickened milk. Other nut milks can be boiled to coagulate the proteins into curds, then the curds can be drained of excess fluid, blended until smooth, and heated gently to thicken them further. To impart more flavor to the milk, a small fraction of the nuts can be roasted before grinding.

Characteristics of Some Common Nuts Almonds Almonds are the world's largest tree-nut crop. They're the seed of a plum-like stone fruit, or drupe; the tree is a very close relative of the plum and peach. There are several dozen wild or minor species, but the cultivated almond, Almonds are the world's largest tree-nut crop. They're the seed of a plum-like stone fruit, or drupe; the tree is a very close relative of the plum and peach. There are several dozen wild or minor species, but the cultivated almond, Prunus amygdalus, Prunus amygdalus, came from western Asia and had been domesticated by the Bronze Age. California is now the largest producer. Thanks to their high content of antioxidant vitamin E and low levels of polyunsaturated fats, almonds have a relatively long shelf life. came from western Asia and had been domesticated by the Bronze Age. California is now the largest producer. Thanks to their high content of antioxidant vitamin E and low levels of polyunsaturated fats, almonds have a relatively long shelf life.

Almonds are the main ingredient in marzipan, a paste of sugar and almonds finely ground together and molded and dried into decorative shapes, a Middle Eastern invention that became popular in Europe during the medieval Crusades. Leonardo da Vinci made marzipan sculptures for the Milanese court of Ludovico Sforza in 1470, and wrote that he "observed with pain that [they] gobble up all the sculptures I give them, right to the last morsel." Almond paste is also commonly used as a pastry filling or the base for macaroons, cookies whose only other structural ingredient is egg whites.

Almond Milk and Cream in Medieval TimesBlancmangeTake capons and seeth them, then take them up. Take blanched almonds, grind them, and mix them with the same broth. Cast this milk in a pot. Wash rice, and add, and let it seeth. Then take brawn of capons, tear it small and add. Take lard, sugar and salt, and cast therein. Let it seeth. Then a.s.semble it and decorate it with aniseed confected white or red, and with fried almonds, and serve it forth.- The Forme of Cury, The Forme of Cury, ca. 1390 ca. 1390Cream of Almond MilkTake almond milk, and boil it, and when it is boiled take it from the fire, and sprinkle on a little vinegar. Then spread it on a cloth, and cast sugar on it, and when it is cold gather it together, and leche [slice] it in dishes, and serve it forth.- From a medieval ma.n.u.script, published in R. Warner, Antiquitates Culinariae Antiquitates Culinariae, 1791 Why Almonds Don't Taste Like Almond Flavoring Curiously, standard domesticated almonds taste delicately nutty, nothing like the strong and distinctive flavoring called "almond extract." Strong almond flavor is found only in wild or bitter almonds, which are inedibly bitter and toxic. They contain a defensive system that generates deadly and bitter hydrogen cyanide when the kernel is damaged (p. 258). It's estimated that eating a few bitter almonds at a sitting could kill a child. But it turns out that one by-product of cyanide production is benzaldehyde, a volatile molecule that is the essence of wild almond flavor, and that contributes to the aromas of cherry, apricot, plum, and peach. Our safe "sweet" almond varieties lack both the bitterness and the characteristic aroma. Curiously, standard domesticated almonds taste delicately nutty, nothing like the strong and distinctive flavoring called "almond extract." Strong almond flavor is found only in wild or bitter almonds, which are inedibly bitter and toxic. They contain a defensive system that generates deadly and bitter hydrogen cyanide when the kernel is damaged (p. 258). It's estimated that eating a few bitter almonds at a sitting could kill a child. But it turns out that one by-product of cyanide production is benzaldehyde, a volatile molecule that is the essence of wild almond flavor, and that contributes to the aromas of cherry, apricot, plum, and peach. Our safe "sweet" almond varieties lack both the bitterness and the characteristic aroma.

Bitter almonds are generally unavailable in the United States, while in Europe they're used like a spice, added in small numbers to flavor marzipan made from sweet almonds, as well as to amaretti cookies, amaretto liqueur, and other dishes. Apricot and peach kernels are readily available alternative sources of benzaldehyde, though they don't have the intense and otherwise fine flavor of bitter almonds. German cooks make versions of marzipan called persipan persipan with apricot and peach kernels. with apricot and peach kernels.

Brazil Nuts Brazil nuts are unusually large, an inch/2.5 cm or more long, and double the weight of almonds and cashews. They're the seeds of a large tree ( Brazil nuts are unusually large, an inch/2.5 cm or more long, and double the weight of almonds and cashews. They're the seeds of a large tree (Bertholletia excelsa, 150 ft/50 m tall, 6 ft/2 m across) native to the Amazon region of South America, where they develop in groups of 8 to 24 inside a hard, coconutsized sh.e.l.l. South American countries are still the main producers. The pods are gathered only after they fall to the ground. Because they weigh about 5 pounds, they can be lethal missiles, and harvesters must carry s.h.i.+elds to protect themselves. The edible portion of the seed is an immensely swollen embryonic stem. Thanks to their size and high oil content, two large Brazil nuts are the caloric equivalent of one egg. 150 ft/50 m tall, 6 ft/2 m across) native to the Amazon region of South America, where they develop in groups of 8 to 24 inside a hard, coconutsized sh.e.l.l. South American countries are still the main producers. The pods are gathered only after they fall to the ground. Because they weigh about 5 pounds, they can be lethal missiles, and harvesters must carry s.h.i.+elds to protect themselves. The edible portion of the seed is an immensely swollen embryonic stem. Thanks to their size and high oil content, two large Brazil nuts are the caloric equivalent of one egg.

Brazil nuts are notable for containing the highest levels of selenium of any food. Selenium helps to prevent the development of cancer, apparently by several different means, including an antioxidant enzyme and by inducing damaged cells to die. However, an overdose is toxic. The World Health Organization recommends a maximum daily selenium intake corresponding to just a half-oz/14 gm of Brazil nuts.

The almond, a close relative of the peach, plum, and cherry, with its stony sh.e.l.l.

Almond Extracts and ImitationsThe commonest form of bitter-almond flavor is a bottled extract, which contains aromatic benzaldehyde without the cyanide that accompanies it in the almonds themselves. "Pure" almond extract is derived from bitter almonds, while "natural" extract usually contains benzaldehyde produced from ca.s.sia bark (p. 424), and "imitation" extract contains benzaldehyde synthesized from pure chemicals.

Cashews Like the Brazil nut, cashews come from the Amazon region, whose natives gave us the name. But the tree was successfully transplanted to India and East Africa by the Portuguese, and today these regions are the world's largest producers. The cashew is second only to the almond in world trade. It's a relative of poison ivy, and that's why we never see cashews for sale in the sh.e.l.l. The sh.e.l.l contains an irritating oil that must be driven off by heating before the seed can be carefully extracted without contamination. In the producing countries, the seed-containing fruit is often discarded in favor of the swollen stem tip or "false fruit" called the cashew apple, which is enjoyed either fresh, cooked, or fermented into an alcoholic drink. Like the Brazil nut, cashews come from the Amazon region, whose natives gave us the name. But the tree was successfully transplanted to India and East Africa by the Portuguese, and today these regions are the world's largest producers. The cashew is second only to the almond in world trade. It's a relative of poison ivy, and that's why we never see cashews for sale in the sh.e.l.l. The sh.e.l.l contains an irritating oil that must be driven off by heating before the seed can be carefully extracted without contamination. In the producing countries, the seed-containing fruit is often discarded in favor of the swollen stem tip or "false fruit" called the cashew apple, which is enjoyed either fresh, cooked, or fermented into an alcoholic drink.

Cashews are unusual among oily nuts in containing a significant amount of starch (around 12% of their weight), which makes them more effective than most nuts at thickening water-based dishes (soups, stews, Indian milk-based desserts).

Chestnuts Chestnuts come from several different species of large trees in the genus Chestnuts come from several different species of large trees in the genus Castanea, Castanea, which are found in Europe, Asia, and North America. They're unlike the other common nuts in storing their energy for the future seedling in the form of starch, not oil. Chestnuts are thus usually thoroughly cooked and have a mealy texture. Since prehistory they have been dried, ground into flour, and used in the same way that the starchy cereals are, to make gruels, breads, pastas, cakes, and provide substance in soups. Before the arrival of the potato and corn from the New World, chestnuts were an essential subsistence food in mountainous and marginal agricultural areas of Italy and France. At the opposite extreme, a luxurious chestnut specialty invented in the 17th century is which are found in Europe, Asia, and North America. They're unlike the other common nuts in storing their energy for the future seedling in the form of starch, not oil. Chestnuts are thus usually thoroughly cooked and have a mealy texture. Since prehistory they have been dried, ground into flour, and used in the same way that the starchy cereals are, to make gruels, breads, pastas, cakes, and provide substance in soups. Before the arrival of the potato and corn from the New World, chestnuts were an essential subsistence food in mountainous and marginal agricultural areas of Italy and France. At the opposite extreme, a luxurious chestnut specialty invented in the 17th century is marrons glaces, marrons glaces, large chestnuts that are cooked, slowly infused over a day or two with a vanilla-flavored syrup, then glazed with a more concentrated syrup. large chestnuts that are cooked, slowly infused over a day or two with a vanilla-flavored syrup, then glazed with a more concentrated syrup.

The American enjoyment of our native chestnut, Castanea dentata, Castanea dentata, was brought to a sad end in the early 20th century, when in the course of a few decades, an imported Asian fungal blight wiped out a tree that used to make up 25% or more of the eastern hardwood forest. Today, the world's leading chestnut producers are China, Korea, Turkey, and Italy. was brought to a sad end in the early 20th century, when in the course of a few decades, an imported Asian fungal blight wiped out a tree that used to make up 25% or more of the eastern hardwood forest. Today, the world's leading chestnut producers are China, Korea, Turkey, and Italy.

Because of its high initial moisture content, the chestnut is quite perishable. Chestnuts are best kept covered and refrigerated, and should be eaten fairly quickly. If freshly gathered, however, they should be cured at room temperature for a few days. This improves the flavor by permitting some starch to be converted into sugar before the cells' metabolism is slowed down.

Why Brazil Nuts Rise to the Top of the BowlA paper published in the 1987 Physical Review Letters Physical Review Letters tried to crack a hard nut: why is it that in a bowl of mixed nuts, the small nuts end up at the bottom and the Brazil nuts on top? The same kind of segregation by size takes place in many different mixtures, from corn flakes to the soil. It turns out that objects in a mixture are pulled downward through gaps in the mixture by gravity - and small gaps are more common than large gaps, so small objects more frequently sink than large ones. tried to crack a hard nut: why is it that in a bowl of mixed nuts, the small nuts end up at the bottom and the Brazil nuts on top? The same kind of segregation by size takes place in many different mixtures, from corn flakes to the soil. It turns out that objects in a mixture are pulled downward through gaps in the mixture by gravity - and small gaps are more common than large gaps, so small objects more frequently sink than large ones.

Coconuts Coconuts are the largest and most important of all nuts. They are the stone of a drupe, the fruit of Coconuts are the largest and most important of all nuts. They are the stone of a drupe, the fruit of Cocos nucifera, Cocos nucifera, large (to 100 ft/30 m) tree-like palms that are more closely related to the gra.s.ses than to other nut trees. They're thought to have originated in tropical Asia, but their hardy fruits apparently floated to many parts of the world before humans began to transport them. They were largely unknown to Europe until the early Middle Ages. About 20 billion nuts are produced each year, mainly in the Philippines, India, and Indonesia. The word large (to 100 ft/30 m) tree-like palms that are more closely related to the gra.s.ses than to other nut trees. They're thought to have originated in tropical Asia, but their hardy fruits apparently floated to many parts of the world before humans began to transport them. They were largely unknown to Europe until the early Middle Ages. About 20 billion nuts are produced each year, mainly in the Philippines, India, and Indonesia. The word coconut coconut comes from the Portuguese comes from the Portuguese coco, coco, which means goblin or monkey. The markings on the stem end of the nut can look uncannily like a face. The tiny embryo resides under one of the eyes, through which it grows when it sprouts. which means goblin or monkey. The markings on the stem end of the nut can look uncannily like a face. The tiny embryo resides under one of the eyes, through which it grows when it sprouts.

Coconuts consist of a thick fibrous fruit layer, the husk, within which is the seed proper enclosed in a woody sh.e.l.l. The meat and milk const.i.tute the seed's endosperm, which contains enough nutrients and moisture to support the seedling's growth for more than a year. The entire fruit may weight 25 lb/12 kg, of which about a quarter is meat, 15% free water.

Coconut provides a backbone flavor in many tropical cuisines, from southern India and Southeast Asia to Africa and South America. It's often used in the form of coconut milk, which provides a rich, flavorful liquid in which to cook all kinds of foods, from meats and fish to vegetables and rice. Since the coconut meat can't be roasted intact, its flavor is developed by carefully toasting small flakes or shreds. Unlike other nuts, which provide crunchiness or smooth richness depending on how finely they're broken, coconut has a persistent, chewy texture unless toasted and kept very dry.

The distinctive sweet, rich aroma of coconut is created by derivatives of saturated fatty acids called lactones (octa-, deca-, dodeca-, tetradecalactones) - peaches are also flavored by lactones - while roasting generates more generic nutty notes (from pyrazines, pyrroles, furans).

Coconut Development Coconut fruits are borne and mature year-round. At around four months, the nut fills with liquid; at five, it reaches its full size and begins to develop a jelly-like meat; at seven its sh.e.l.l begins to harden, and it's mature at a year. Immature coconuts, around five to seven months old, offer their own pleasures: a sweet liquid called coconut water (about 2% sugars); and a moist, delicate, gelatinous meat that's mainly water, sugars and other carbohydrates. In the mature coconut of 1112 months, the liquid has become less sweet and less abundant, and the meat has become firm, fatty, and white. The meat is about 45% water, 35% fat, 10% carbohydrate, 5% protein. Coconut fruits are borne and mature year-round. At around four months, the nut fills with liquid; at five, it reaches its full size and begins to develop a jelly-like meat; at seven its sh.e.l.l begins to harden, and it's mature at a year. Immature coconuts, around five to seven months old, offer their own pleasures: a sweet liquid called coconut water (about 2% sugars); and a moist, delicate, gelatinous meat that's mainly water, sugars and other carbohydrates. In the mature coconut of 1112 months, the liquid has become less sweet and less abundant, and the meat has become firm, fatty, and white. The meat is about 45% water, 35% fat, 10% carbohydrate, 5% protein.

The coconut. This ma.s.sive seed is borne in a thick, dry husk and contains both solid and liquid endosperm to feed the small embryo, which emerges from one of the three "eyes" at the end of the sh.e.l.l.

Coconut Meat and Milk A good fresh coconut should feel heavy and contain enough liquid to slosh audibly. If coconut meat is pounded in a mortar or ground finely in a blender, it forms a thick paste consisting of microscopic oil droplets and cell debris suspended in water, which makes up about half the volume. Coconut milk is made by mixing the paste with some additional water and straining to remove the solid particles. Left to stand for an hour, this milk separates into a fat-rich cream layer and a thin "skim" layer. Coconut milk can also be made from dried shredded coconut, and is readily available canned. A good fresh coconut should feel heavy and contain enough liquid to slosh audibly. If coconut meat is pounded in a mortar or ground finely in a blender, it forms a thick paste consisting of microscopic oil droplets and cell debris suspended in water, which makes up about half the volume. Coconut milk is made by mixing the paste with some additional water and straining to remove the solid particles. Left to stand for an hour, this milk separates into a fat-rich cream layer and a thin "skim" layer. Coconut milk can also be made from dried shredded coconut, and is readily available canned.

Coconut Oil For part of the 20th century, coconut oil was the most important vegetable oil in the world. It can be produced in large quant.i.ties, is very stable, and has a melting point similar to that of milk fat. But the very quality that makes it stable and versatile also made it appear to be nutritionally undesirable. The fats that make up coconut oil are nearly 90% saturated (15% caprylic and capric, 45% lauric, 18% myristic, 10% palmitic, and just 8% monounsaturated oleic), which means that they raise blood cholesterol levels. During the 1970s and '80s, manufacturers of processed foods therefore replaced coconut oil with less saturated, partly hydrogenated seed oils - which now turn out to contain undesirable trans fatty acids (p. 38). For part of the 20th century, coconut oil was the most important vegetable oil in the world. It can be produced in large quant.i.ties, is very stable, and has a melting point similar to that of milk fat. But the very quality that makes it stable and versatile also made it appear to be nutritionally undesirable. The fats that make up coconut oil are nearly 90% saturated (15% caprylic and capric, 45% lauric, 18% myristic, 10% palmitic, and just 8% monounsaturated oleic), which means that they raise blood cholesterol levels. During the 1970s and '80s, manufacturers of processed foods therefore replaced coconut oil with less saturated, partly hydrogenated seed oils - which now turn out to contain undesirable trans fatty acids (p. 38).

Given our current and broader understanding of other dietary influences on heart disease (p. 255), there's no reason not to enjoy the coconut's riches as part of a balanced diet that includes plenty of protective fruits, vegetables, and other seeds.

Ginkgo Nuts Gingko nuts are the starchy kernels of Gingko nuts are the starchy kernels of Ginkgo biloba, Ginkgo biloba, the last survivor of a tree family that was prominent during the age of the dinosaurs. The nuts are borne inside fleshy fruits that develop a strong rancid smell when ripe. In Asia, the tree's home, the fruits are fermented in vats of water to soften and remove the pulp, and the seeds are washed, dried, and roasted or boiled, either in-sh.e.l.l or sh.e.l.led. The kernel has a distinctive but mild flavor. the last survivor of a tree family that was prominent during the age of the dinosaurs. The nuts are borne inside fleshy fruits that develop a strong rancid smell when ripe. In Asia, the tree's home, the fruits are fermented in vats of water to soften and remove the pulp, and the seeds are washed, dried, and roasted or boiled, either in-sh.e.l.l or sh.e.l.led. The kernel has a distinctive but mild flavor.

Hazelnuts Hazelnuts come from a few of the 15 species of mainly bushy trees in the northern-hemisphere genus Hazelnuts come from a few of the 15 species of mainly bushy trees in the northern-hemisphere genus Corylus. Corylus avellana Corylus. Corylus avellana and and C. maxima C. maxima are native to temperate Eurasia and were widely exploited in prehistoric times for their nuts and rapidly produced shoots, which were used as walking sticks and a surface for marshy ground. A much taller tree, are native to temperate Eurasia and were widely exploited in prehistoric times for their nuts and rapidly produced shoots, which were used as walking sticks and a surface for marshy ground. A much taller tree, C. colurna, C. colurna, accounts for much of the production in the Black Sea region of Turkey. Another term for the nut is "filbert," which in the United Kingdom is applied to the more elongated varieties, and which may come from St. Philibert's Day in late August, when hazelnuts begin to ripen. The late Roman cookbook of Apicius called for hazelnuts in sauces for birds, boar, and mullet; they're an alternative to almonds in Spanish picada and romesco sauces, and an ingredient in the spicy Egyptian spread called dukka and the Italian liqueur frangelico. Hazelnuts remain especially popular in Europe, where Turkey, Italy, and Spain are the main producers. In the United States, nearly all hazelnuts are produced in Oregon. accounts for much of the production in the Black Sea region of Turkey. Another term for the nut is "filbert," which in the United Kingdom is applied to the more elongated varieties, and which may come from St. Philibert's Day in late August, when hazelnuts begin to ripen. The late Roman cookbook of Apicius called for hazelnuts in sauces for birds, boar, and mullet; they're an alternative to almonds in Spanish picada and romesco sauces, and an ingredient in the spicy Egyptian spread called dukka and the Italian liqueur frangelico. Hazelnuts remain especially popular in Europe, where Turkey, Italy, and Spain are the main producers. In the United States, nearly all hazelnuts are produced in Oregon.

Coconut "Gelatin"In addition to products from the seed itself, the coconut palm offers several other distinctive food materials. One of the more unusual is nata de coco, nata de coco, or "coconut gelatin," a moist, translucent ma.s.s of cellulose produced by a vinegar bacterium ( or "coconut gelatin," a moist, translucent ma.s.s of cellulose produced by a vinegar bacterium (Acetobacter xylinum) on the surface of fermenting coconut water. It has little flavor of its own and a uniquely crunchy texture. In the Philippines it's washed of its vinegary home, flavored, packed in sugar syrup, and eaten as a sweet.

The distinctive aroma of hazelnuts comes from a compound dubbed filbertone (heptenone), which is present in small quant.i.ties in the raw nut, but increases 600-to 800-fold when the nuts are fried or boiled.

Macadamia Nuts Macadamia nuts are newcomers to the world's table. They come from two evergreen tropical trees ( Macadamia nuts are newcomers to the world's table. They come from two evergreen tropical trees (Macadamia tetraphylla and and M. integrifolia M. integrifolia) native to northeastern Australia, where the aborigines enjoyed them for thousands of years before they were noticed and named by Europeans (for John Macadam, a Scots-born chemist, in 1858). Macadamias were introduced to Hawaii in the 1890s, and became commercially significant there around 1930. Today Australia and Hawaii are the main producers, but their output remains relatively small, and macadamias are therefore among the most expensive nuts. Because their sh.e.l.ls are extremely hard, they are sold almost exclusively out-of-sh.e.l.l, often packed in cans or bottles to protect them from air and rancidity. Macadamias have the highest fat content of the tree nuts, and it's mostly monounsaturated (65% oleic acid). Their flavor is mild and delicate.

Peanut This popular nut is not a nut, but the seed of a small leguminous bush, This popular nut is not a nut, but the seed of a small leguminous bush, Arachis hypogaea, Arachis hypogaea, which pushes its thin, woody fruit capsules below ground as they mature. The peanut was domesticated in South America, probably Brazil, around 2000 which pushes its thin, woody fruit capsules below ground as they mature. The peanut was domesticated in South America, probably Brazil, around 2000 BCE BCE, and was an important crop in Peru before the time of the Incas. In the 16th century, the Portuguese took it to Africa, India, and Asia, and it soon became a major source of cooking oil in China (peanuts have double the oil content of soybeans). It wasn't until the 19th century that Americans thought of peanuts as anything but animal feed, and not until the early 20th century that the remarkable agricultural scientist George Was.h.i.+ngton Carver encouraged southern farmers to replace weevil-ravaged cotton with peanuts.

Today India and China are by far the largest peanut producers, with the United States a distant third. Most Asian peanuts are crushed for oil and meal; in the United States most are eaten as food. Peanuts are now prominent in several Asian and African traditions. Pureed, they lend richness, substance, and flavor to sauces and soups. Whole and pureed peanuts are used in Thai and Chinese noodle dishes, in sweet bun fillings, in Indonesian dipping sauces and sambal condiments, and in West African stews, soups, cakes, and confections. A popular snack food in both Asia and the southern United States is peanuts boiled in salted water. When boiled in their sh.e.l.ls, peanuts develop a potato-like aroma, with sweet vanilla highlights thanks to the liberation of vanillin from the sh.e.l.l.

In the United States, four varieties are grown for different purposes: large Virginia and small Valencia for nuts sold in the sh.e.l.l, Virginia and small Spanish for mixed nuts and candies, and Runner for baked goods and peanut b.u.t.ter, since its higher content of monounsaturated fat makes it less vulnerable to rancidity.

Peanut b.u.t.ter The modern version of peanut b.u.t.ter was apparently developed around 1890 in St. Louis or in Battle Creek, Michigan. Commercial peanut b.u.t.ter is made by heating the nuts to an internal temperature around 300F/150C to develop flavor, blanching in hot water to remove the skin, and finally grinding them with about 2% salt and up to 6% sugar. The oil can be prevented from separating from the solid peanut particles by adding 35% of a hydrogenated shortening that solidifies as the b.u.t.ter cools and forms a host of tiny crystals that hold the very unsaturated, liquid peanut oil in place. Low-fat peanut b.u.t.ter is made by replacing a portion of the peanuts with soy protein and with sugar. The modern version of peanut b.u.t.ter was apparently developed around 1890 in St. Louis or in Battle Creek, Michigan. Commercial peanut b.u.t.ter is made by heating the nuts to an internal temperature around 300F/150C to develop flavor, blanching in hot water to remove the skin, and finally grinding them with about 2% salt and up to 6% sugar. The oil can be prevented from separating from the solid peanut particles by adding 35% of a hydrogenated shortening that solidifies as the b.u.t.ter cools and forms a host of tiny crystals that hold the very unsaturated, liquid peanut oil in place. Low-fat peanut b.u.t.ter is made by replacing a portion of the peanuts with soy protein and with sugar.

Peanut Flavor Several hundred volatile compounds have been identified in roasted peanuts. The raw seed has a green, bean-like flavor (mainly from green-leaf hexa.n.a.l and the pyrazine that characterizes peas). The roasted aroma is a composite of several sulfur compounds, a number of generically "nutty" pyrazines, and others, some of which have fruity, flowery, fried, and smoky characters. During storage and staling, the nutty pyrazines disappear and painty, cardboard notes increase. Several hundred volatile compounds have been identified in roasted peanuts. The raw seed has a green, bean-like flavor (mainly from green-leaf hexa.n.a.l and the pyrazine that characterizes peas). The roasted aroma is a composite of several sulfur compounds, a number of generically "nutty" pyrazines, and others, some of which have fruity, flowery, fried, and smoky characters. During storage and staling, the nutty pyrazines disappear and painty, cardboard notes increase.

Peanut Oil Thanks to the productivity of the peanut plant in warm climates, peanut oil is an important cooking oil, especially in Asia. It's made by steaming the peanuts to inactivate enzymes and soften the cellular structure, then pressing them; the oil is then clarified and sometimes refined to remove some of the distinctive flavor and impurities that would lower the smoke point. Thanks to the productivity of the peanut plant in warm climates, peanut oil is an important cooking oil, especially in Asia. It's made by steaming the peanuts to inactivate enzymes and soften the cellular structure, then pressing them; the oil is then clarified and sometimes refined to remove some of the distinctive flavor and impurities that would lower the smoke point.

Pecans Pecans are the soft, fatty seeds of a very large tree, a distant relative of the walnut that is native to the Mississippi and other river valleys of central North America, and found as far south as Oaxaca. Pecans are the soft, fatty seeds of a very large tree, a distant relative of the walnut that is native to the Mississippi and other river valleys of central North America, and found as far south as Oaxaca. Carya illinoiensis Carya illinoiensis is one of about 14 species of hickories, and its nuts among the tastiest and easiest to sh.e.l.l. Wild pecans were enjoyed by the native Americans, and apparently made into a kind of milk that was used for drinking, cooking, and possibly fermenting. The earliest intentional plantings may have been made by the Spanish around 1700 in Mexico, and a few decades later the trees were grown in the eastern British colonies. The first improved varieties were made possible in the 1840s by a Louisiana slave named Antoine, who worked out how to graft wood from superior trees onto seedling stocks. Georgia, Texas, and New Mexico are now the largest producers of pecans. is one of about 14 species of hickories, and its nuts among the tastiest and easiest to sh.e.l.l. Wild pecans were enjoyed by the native Americans, and apparently made into a kind of milk that was used for drinking, cooking, and possibly fermenting. The earliest intentional plantings may have been made by the Spanish around 1700 in Mexico, and a few decades later the trees were grown in the eastern British colonies. The first improved varieties were made possible in the 1840s by a Louisiana slave named Antoine, who worked out how to graft wood from superior trees onto seedling stocks. Georgia, Texas, and New Mexico are now the largest producers of pecans.

Compared to the walnut, the pecan is more elongated, the cotyledons thicker and smoother, with a larger proportion of meat to sh.e.l.l. As with walnuts, light-skinned varieties are less astringent than dark-skinned. The distinctive flavor of pecans remains somewhat mysterious. In addition to the generic nutty notes of the pyrazines, one study found a lactone (octalactone) that is also present in coconuts.

Pecans and walnuts are among the nuts with the highest oil and unsaturated fatty acid contents. High oil content generally goes along with fragile texture, which means that the kernels are easily bruised, with seepage of oil to the surface and rapidoxidation and staling. Roasting increases the rate of staling by weakening cells and allowing oil to come into contact with the air. Carefully handled, raw pecans can be stored for years in the freezer.

Food Words: Pine, Walnut, Flax, Sesame Pine, Walnut, Flax, SesameA number of nut names seem simply to name the nuts, without a penumbra of related meanings. This is an indication that almonds and pistachios (from the Greek) and hazelnuts (from the Indo-European) have been basic fare for a very long time. Pine Pine comes from an Indo-European root meaning "to swell, to be fat," probably an allusion to the fat-like resin that the tree exudes. comes from an Indo-European root meaning "to swell, to be fat," probably an allusion to the fat-like resin that the tree exudes. Walnut Walnut is an Old English compound of is an Old English compound of wealh, wealh, meaning "Celt" or "foreigner," and meaning "Celt" or "foreigner," and hnutu, hnutu, "nut," a reflection of the fact that walnuts were introduced to the British Isles from the east. "nut," a reflection of the fact that walnuts were introduced to the British Isles from the east. Flax Flax comes from an Indo-European root meaning "to plait," because flax was originally grown for its stem fibers. And comes from an Indo-European root meaning "to plait," because flax was originally grown for its stem fibers. And sesame sesame comes from two words in the ancient Middle Eastern Akkadian language that meant "oil" and "plant." comes from two words in the ancient Middle Eastern Akkadian language that meant "oil" and "plant."

Pine Nuts Pine nuts are gathered from about a dozen of the 100 species of pines, one of the most familiar evergreen tree families in the Northern Hemisphere. Among the more important sources are the Italian stone pine Pine nuts are gathered from about a dozen of the 100 species of pines, one of the most familiar evergreen tree families in the Northern Hemisphere. Among the more important sources are the Italian stone pine Pinus pinea, Pinus pinea, the Korean or Chinese pine the Korean or Chinese pine P. koraiensis, P. koraiensis, and the southwestern U.S. pinyons and the southwestern U.S. pinyons P. monophylla P. monophylla and and P. edulis. P. edulis. The nuts are borne on the scales of the pine cone, which takes three years to mature. The cones are sun-dried, threshed to shake out the seeds, and the kernels then hulled, nowadays by machine. They have a distinctive, resinous aroma and are rich even for nuts; Asian pine nuts have a higher oil content (78%) than either American or European types (62% and 45% respectively). They're used in many savory and sweet preparations, and pressed to make oil. In Korea, pine pollen is used to make sweets, and Romanians flavor game sauces with the green cones. The nuts are borne on the scales of the pine cone, which takes three years to mature. The cones are sun-dried, threshed to shake out the seeds, and the kernels then hulled, nowadays by machine. They have a distinctive, resinous aroma and are rich even for nuts; Asian pine nuts have a higher oil content (78%) than either American or European types (62% and 45% respectively). They're used in many savory and sweet preparations, and pressed to make oil. In Korea, pine pollen is used to make sweets, and Romanians flavor game sauces with the green cones.