On Food And Cooking Part 39

Rakkyo

Allium chinense Allium chinense

There are many different garlic varieties, with different proportions of sulfur compounds and so different flavors and pungencies. The main commercial varieties are grown for their yield and storage life, not their flavor. Cold growing conditions produce a more intense garlic flavor. Garlic is at its moistest soon after harvest, from late summer to late fall, and becomes more concentrated as it slowly dries out during storage. Refrigerated storage causes a decline in distinctively garlicky flavor, and an increase in more generic onion flavors.

Because the peeling and chopping of the small cloves is tedious work, garlic is sometimes prepared in quant.i.ty and then stored under oil for later use. This procedure turns out to encourage the growth of deadly botulism bacteria, which thrive in the absence of air. Bacterial growth can be prevented by soaking the garlic in acidic vinegar or lemon juice for several hours before putting it under oil, and by storing the container in the refrigerator. Occasionally, acid-pickled garlic turns a strange shade of bluish-green, a reaction that apparently involves one of the sulfurous flavor precursors. This discoloration can be minimized by blanching the garlic before pickling.

Leeks Unlike onions and garlic, leeks don't form useful storage bulbs, and are grown instead for their scallion-like ma.s.s of fresh leaves. (There's one exception to this rule: the leek variety confusingly named "elephant garlic" because it produces a garlic-like bulb cl.u.s.ter that can reach 1 lb/450 gm.) Leeks are very tolerant of cold and in many regions can be harvested throughout the winter. They grow to a large size, and the prized white base portion of their leaves is often increased (to as much as 1 ft/3 m long and 3 in/7.5 cm thick) by hilling soil up around the growing plant to s.h.i.+eld more of it from the sun. This practice also fills the s.p.a.ces between leaves with grit, and necessitates careful was.h.i.+ng. The inner leaves (and seldom-used roots) have the strongest flavor. The upper green portion of each leek leaf is edible, but tends to be tougher and to have a less oniony, more cabbage-like flavor than the lower white portion. It's also rich in long-chain carbohydrates that give the cooked vegetable a slippery texture, will gel when chilled, and can lend body to soups and stews. Unlike onions and garlic, leeks don't form useful storage bulbs, and are grown instead for their scallion-like ma.s.s of fresh leaves. (There's one exception to this rule: the leek variety confusingly named "elephant garlic" because it produces a garlic-like bulb cl.u.s.ter that can reach 1 lb/450 gm.) Leeks are very tolerant of cold and in many regions can be harvested throughout the winter. They grow to a large size, and the prized white base portion of their leaves is often increased (to as much as 1 ft/3 m long and 3 in/7.5 cm thick) by hilling soil up around the growing plant to s.h.i.+eld more of it from the sun. This practice also fills the s.p.a.ces between leaves with grit, and necessitates careful was.h.i.+ng. The inner leaves (and seldom-used roots) have the strongest flavor. The upper green portion of each leek leaf is edible, but tends to be tougher and to have a less oniony, more cabbage-like flavor than the lower white portion. It's also rich in long-chain carbohydrates that give the cooked vegetable a slippery texture, will gel when chilled, and can lend body to soups and stews.

Stems and Stalks: Asparagus, Celery, and Others Vegetables derived from plant stems and stalks often present a particular challenge to the cook. Stems and stalks support other plant parts and conduct essential nutrients to and from them, so they consist in large part of fibrous vascular tissue and special stiffening fibers - for example, the ridges along the outer edge of celery and cardoons - that are from 2 to 10 times tougher than the vascular fibers themselves. These fibrous materials become increasingly reinforced with insoluble cellulose as the stem or stalk matures. Sometimes there's nothing to do except to strip away the fibers, or cut the vegetable into thin pieces to minimize their fibrousness, or puree them and strain off the fibers. The keys to tender celery, cardoons, and rhubarb are on the farm rather than in the kitchen: choosing the right variety, providing plenty of water so that the stalks can support themselves with turgor pressure (p. 264), and providing mechanical support by hilling with soil or tying the stalks together, so that mechanical stress doesn't induce fiber growth.

Garlic on the BreathDoes the chemistry of garlic flavor offer any help when it comes to dealing with garlic breath? One major component of garlic breath appears to be various chemical relatives of skunk spray (e.g., methanethiol) that persist in the mouth. Another component (methyl allyl sulfide) is apparently generated from garlic as it pa.s.ses through the digestive system, and peaks in the breath between 6 and 18 hours after the meal. Residual thiols in the mouth can be transformed into odorless molecules by the browning enzymes in many raw fruits and vegetables (p. 269), so eating a salad or an apple will help. Mouthwashes that contain strong oxidizing agents (e.g., chloramine) are also effective. Sulfides from the digestive system are probably beyond our reach!

One group of stem vegetables is inherently tender: the tips of such crop plants as peas, melons and squashes, grapevines, and hops, which grow rapidly in the spring, and have long been enjoyed as among the first fresh vegetables of the new season.

Asparagus Asparagus is the main stalk of a plant in the lily family, Asparagus officinalis, Asparagus officinalis, a native of Eurasia that was a delicacy in Greek and Roman times. The stalk doesn't support ordinary leaves; the small projections from the stem are leaf-like bracts that s.h.i.+eld immature cl.u.s.ters of feathery photosynthetic branches. The stalks grow up from long-lived underground rhizomes, and have been widely prized as a tender manifestation of spring. Many other vegetables have been called "poor man's asparagus," including young leeks, blackberry shoots, and hop shoots. It remains expensive today because the shoots grow at different rates and must be harvested by hand. In Europe, the even more labor-intensive white version, blanched by being covered with soil and cut from underground, has been popular since the 18th century. It has a more delicate aroma than green asparagus (which is rich in dimethyl sulfide and other sulfur volatiles), and some bitterness toward the stem end. Exposed to light after harvest, white asparagus will turn yellow or red. Purple asparagus varieties are colored with anthocyanins, whose color generally fades during cooking, leaving the green of the chlorophyll. a native of Eurasia that was a delicacy in Greek and Roman times. The stalk doesn't support ordinary leaves; the small projections from the stem are leaf-like bracts that s.h.i.+eld immature cl.u.s.ters of feathery photosynthetic branches. The stalks grow up from long-lived underground rhizomes, and have been widely prized as a tender manifestation of spring. Many other vegetables have been called "poor man's asparagus," including young leeks, blackberry shoots, and hop shoots. It remains expensive today because the shoots grow at different rates and must be harvested by hand. In Europe, the even more labor-intensive white version, blanched by being covered with soil and cut from underground, has been popular since the 18th century. It has a more delicate aroma than green asparagus (which is rich in dimethyl sulfide and other sulfur volatiles), and some bitterness toward the stem end. Exposed to light after harvest, white asparagus will turn yellow or red. Purple asparagus varieties are colored with anthocyanins, whose color generally fades during cooking, leaving the green of the chlorophyll.

Harvested early and fresh from the soil, asparagus is very juicy and noticeably sweet (perhaps 4% sugar). As the season progresses, the rhizomes become depleted of stored energy, and sugar levels in the shoots decline. Once harvested, the actively growing shoot continues to consume its sugars, and does so more rapidly than any other common vegetable. Its flavor flattens out; it loses its juiciness, and it becomes increasingly fibrous from the base up. These changes are especially rapid in the first 24 hours after harvest, and are accelerated by warmth and light. Moisture and sugar losses can be partly remedied by soaking the spears in dilute sugar water (510%, or 510 gm per 100 ml/12 teaspoons per half-cup) before cooking. White asparagus is always more fibrous than green and toughens faster in storage. It and some green asparagus may be peeled to remove some unsoftenable tissue, but woody lignin formation also takes place deeper in the stem. Cooks have dealt with this internal toughening in the same way for 500 years: they bend the stalk, and allow mechanical stress to find the border between tough and tender and break the two apart.

Asparagus and its peculiar branches, the phylloclades, which are cl.u.s.tered near the tip of the immature stem.

Asparagus has long been notorious for an unusual side effect on those who eat it: it gives a strong odor to their urine. Apparently the body metabolizes a sulfur-containing substance, asparagusic acid, a close chemical relative of the essence of skunk spray called methanethiol. In part because some people claim to be immune to this effect, biochemists have studied this phenomenon in some detail. It now appears that thanks to genetic differences, most but not all people do produce methanethiol after eating asparagus, and most but not all are able to smell it.

The Carrot Family: Celery and Fennel The carrot family has provided two aromatic stalk vegetables.

Celery Celery, Celery, Apium graveolens, Apium graveolens, is the mild, enlarged version of a bitter, thin-stalked Eurasian herb called smallage. Chinese celery (var. is the mild, enlarged version of a bitter, thin-stalked Eurasian herb called smallage. Chinese celery (var. secalinum secalinum) is closer in form and favor to smallage, while Asian water celery is a more distant relative (Oenanthe javanica) with a distinctive flavor. Our familiar celery was apparently bred in 15thcentury Italy, and remained a delicacy well into the 19th. It consists of greatly enlarged, pleasantly crunchy leaf stalks, or petioles, and has a distinctive but subtle aroma due to unusual compounds called phthalides that it shares with walnuts (hence their successful pairing in Waldorf salads), and terpenes that provide light pine and citrus notes. Celery is often combined with carrots and onions in gently fried aromatic base preparations for other dishes (French mirepoix, mirepoix, Italian Italian soffrito, soffrito, Spanish Spanish sofregit; sofregit; in the Louisiana Cajun "trinity" of aromatics the carrots are replaced by green capsic.u.ms). In parts of Europe, celery has been preferred in a more delicately favored blanched form, originally produced by covering the growing stalks with soil, then by growing pale green "self-blanching" varieties. Celery is often served raw, and its crispness is maximized by presoaking in cold water (p. 265). Both celery and celery root contain defensive chemicals that can cause skin and other reactions in sensitive people (p. 259). in the Louisiana Cajun "trinity" of aromatics the carrots are replaced by green capsic.u.ms). In parts of Europe, celery has been preferred in a more delicately favored blanched form, originally produced by covering the growing stalks with soil, then by growing pale green "self-blanching" varieties. Celery is often served raw, and its crispness is maximized by presoaking in cold water (p. 265). Both celery and celery root contain defensive chemicals that can cause skin and other reactions in sensitive people (p. 259).

Fennel Bulb or Florence or finocchio fennel is a vegetable variety (var. azoric.u.m) of Bulb or Florence or finocchio fennel is a vegetable variety (var. azoric.u.m) of Foeniculum vulgare, Foeniculum vulgare, the plant that produces fennel seeds (p. 415). Its enlarged leaf-stalk bases form a tight, bulb-like cl.u.s.ter. (The rest of the leaf stalk, the equivalent of celery stalk, remains tough and fibrous.) Fennel has a strong anise aroma thanks to the same chemical (anethole) that flavors anise seeds and star anise, and this makes fennel a more dominating, less versatile ingredient than celery and carrots. It also has a distinct citrus note (from the terpene limonene) that's especially prominent in the spa.r.s.e foliage. Fennel is eaten both raw, thinly sliced and crunchy, and cooked, often braised or in a gratin. the plant that produces fennel seeds (p. 415). Its enlarged leaf-stalk bases form a tight, bulb-like cl.u.s.ter. (The rest of the leaf stalk, the equivalent of celery stalk, remains tough and fibrous.) Fennel has a strong anise aroma thanks to the same chemical (anethole) that flavors anise seeds and star anise, and this makes fennel a more dominating, less versatile ingredient than celery and carrots. It also has a distinct citrus note (from the terpene limonene) that's especially prominent in the spa.r.s.e foliage. Fennel is eaten both raw, thinly sliced and crunchy, and cooked, often braised or in a gratin.

Asparagus AromaticsNot only can people differ in their ability to detect the product of asparagus metabolism, those who can detect it differ in their a.s.sessment.[Asparagus] cause a filthy and disagreeable smell in the urine, as everybody knows.- Louis Lemery, Treatise of All Sorts of Foods, Treatise of All Sorts of Foods, 1702 1702...all night long after a dinner at which I had partaken of [asparagus], they played (lyrical and coa.r.s.e in their jesting as the fairies in Shakespeare's Dream Dream) at transforming my chamber pot into a vase of aromatic perfume.- Marcel Proust, In Search of Lost Time, In Search of Lost Time, 1913 1913 The Cabbage Family: Kohlrabi and Rutabaga Kohlrabi Kohlrabi is a version of the basic cabbage plant ( Kohlrabi is a version of the basic cabbage plant (Bra.s.sica oleracea var. var. gongylodes gongylodes) in which the main stem swells to several inches in diameter. It has the moist texture and mild flavor of broccoli stalk. The name comes from the German for "cabbage turnip," and indeed kohlrabi resembles a turnip in its rounded appearance. Young kohlrabi are tender enough to eat raw for their crisp moistness or cook briefly; overmature stems are woody.

Rutabaga The rutabaga, or swede, is the result of a cross between the turnip and cabbage species, and is thought to have been born sometime before 1600 in Eastern Europe, perhaps in gardens where kale and turnips were growing side by side. Like kohlrabi, it's a swollen portion of the main stem; like the turnip, it may be white or yellow. It is sweeter and starchier than the turnip or kohlrabi, though still with only half the carbohydrate content of a potato; it's often boiled and mashed. The rutabaga, or swede, is the result of a cross between the turnip and cabbage species, and is thought to have been born sometime before 1600 in Eastern Europe, perhaps in gardens where kale and turnips were growing side by side. Like kohlrabi, it's a swollen portion of the main stem; like the turnip, it may be white or yellow. It is sweeter and starchier than the turnip or kohlrabi, though still with only half the carbohydrate content of a potato; it's often boiled and mashed.

Tropical Stems: Bamboo Shoots and Hearts of Palm Bamboo Shoots Bamboo shoots are the very young stems of several tropical Asian bamboos (species of Bamboo shoots are the very young stems of several tropical Asian bamboos (species of Phyllostachys Phyllostachys and others), which are woody members of the gra.s.s family. As the new shoots begin to break the soil surface, additional soil is heaped on to minimize their exposure to light and thereby their production of bitter cyanide-generating compounds (p. 258). Cooks and food manufacturers then eliminate all cyanide compounds from the fresh shoots by boiling them in water until they're no longer bitter. Along with Chinese water chestnuts and lotus root, bamboo shoots are valued for the ability to retain their firm, crisp, meaty texture during and after cooking, and even after the extreme heat treatment of canning (p. 283). Their flavor has an unusual medicinal or barnyard note thanks to cresol, as well as more common bready and brothy aromas from simple sulfur compounds (methional, dimethyl sulfide). and others), which are woody members of the gra.s.s family. As the new shoots begin to break the soil surface, additional soil is heaped on to minimize their exposure to light and thereby their production of bitter cyanide-generating compounds (p. 258). Cooks and food manufacturers then eliminate all cyanide compounds from the fresh shoots by boiling them in water until they're no longer bitter. Along with Chinese water chestnuts and lotus root, bamboo shoots are valued for the ability to retain their firm, crisp, meaty texture during and after cooking, and even after the extreme heat treatment of canning (p. 283). Their flavor has an unusual medicinal or barnyard note thanks to cresol, as well as more common bready and brothy aromas from simple sulfur compounds (methional, dimethyl sulfide).

Hearts of Palm Hearts of palm are the growing stem tips of various palm trees, especially the South American peach palm Hearts of palm are the growing stem tips of various palm trees, especially the South American peach palm Bactris gasipaes, Bactris gasipaes, which readily resprouts after its tip is cut. The tissue is fine-grained and crisp, with a sweet and slightly nutty taste, and is eaten both raw and cooked. Hearts of other palms may have a bitter edge and a tendency to brown discoloration; and their harvest often results in the wasteful death of the entire tree. which readily resprouts after its tip is cut. The tissue is fine-grained and crisp, with a sweet and slightly nutty taste, and is eaten both raw and cooked. Hearts of other palms may have a bitter edge and a tendency to brown discoloration; and their harvest often results in the wasteful death of the entire tree.

Other Stem and Stalk vegetables Cactus Pads or Nopales Cactus pads, nopales, and nopalitos are all names for the flattened stem segments of the p.r.i.c.kly-pear cactus Cactus pads, nopales, and nopalitos are all names for the flattened stem segments of the p.r.i.c.kly-pear cactus Opuntia ficus-indica Opuntia ficus-indica (p. 369), a native of the arid regions of Mexico and the U.S. Southwest. They're eaten raw in salads or salsas, baked, fried, pickled, and added to stews. Nopalitos are remarkable for two things: a mucilage that probably helps them retain water, and that can give them a somewhat slimy consistency (dry cooking methods minimize this), and a startling tartness thanks to their malic acid content. Cactuses, purslane, and other plants that live in hot, dry environments have developed a special form of photosynthesis in which they keep their pores closed during the day to conserve water, then open them at night to take in carbon dioxide, which they then store in the form of malic acid. During the day, they use the energy from sunlight to convert the malic acid to glucose. Pads harvested in the early morning therefore contain as much as 10 times more malic acid than pads harvested in the afternoon. The acid levels in the pads slowly drop after harvest, so the difference is less apparent after a few days. (p. 369), a native of the arid regions of Mexico and the U.S. Southwest. They're eaten raw in salads or salsas, baked, fried, pickled, and added to stews. Nopalitos are remarkable for two things: a mucilage that probably helps them retain water, and that can give them a somewhat slimy consistency (dry cooking methods minimize this), and a startling tartness thanks to their malic acid content. Cactuses, purslane, and other plants that live in hot, dry environments have developed a special form of photosynthesis in which they keep their pores closed during the day to conserve water, then open them at night to take in carbon dioxide, which they then store in the form of malic acid. During the day, they use the energy from sunlight to convert the malic acid to glucose. Pads harvested in the early morning therefore contain as much as 10 times more malic acid than pads harvested in the afternoon. The acid levels in the pads slowly drop after harvest, so the difference is less apparent after a few days.

Cardoons Cardoons are the leaf stalks of Cardoons are the leaf stalks of Cynara cardunculus, Cynara cardunculus, the Mediterranean plant from which the artichoke ( the Mediterranean plant from which the artichoke (C. scolymus) apparently descends; the stalks are often covered for several weeks before harvest to protect them from sunlight, or blanch them. Cardoons have a flavor quite similar to the artichoke's, and are abundantly endowed with astringent, bitter phenolic compounds that quickly form brown complexes when the tissue is cut or damaged. They're often cooked in milk, whose proteins bind phenolic compounds and can reduce astringency (as in tea, p. 440). Phenolics can also cause a toughening of cell walls, and cardoon fibers are often remarkably resistant to softening. Bringing them to a gradual boil in several changes of water can help leach out phenolics and soften them, though flavor is leached out as well. Sometimes it's necessary to peel the reinforcing fibers from the cardoon stalk, or cut it into thin cross sections to keep the fibers relatively short and inconspicuous.

Fiddleheads Fiddleheads are the immature leaf stalk and fronds of ferns, named for the resemblance of their furled tips to the scroll of a violin. Long a traditional springtime delicacy, harvested as the fern fronds begin to elongate and unroll but before they toughen, fiddleheads are now cause for some caution. A common species especially enjoyed in j.a.pan and Korea, the bracken fern Fiddleheads are the immature leaf stalk and fronds of ferns, named for the resemblance of their furled tips to the scroll of a violin. Long a traditional springtime delicacy, harvested as the fern fronds begin to elongate and unroll but before they toughen, fiddleheads are now cause for some caution. A common species especially enjoyed in j.a.pan and Korea, the bracken fern Pteridium aequilinum, Pteridium aequilinum, has been found to contain a potent DNA-damaging chemical (p. 259). It should be avoided. Stalks of the ostrich fern, various species of has been found to contain a potent DNA-damaging chemical (p. 259). It should be avoided. Stalks of the ostrich fern, various species of Matteuccia, Matteuccia, are thought to be safer to eat. are thought to be safer to eat.

Rhubarb Rhubarb, the leaf stalks of a large perennial herb, is unusual for containing a high concentration of oxalic acid. Its main use in the West is as a tart stand-in for fruit, so I describe it in the next chapter (p. 367). Rhubarb, the leaf stalks of a large perennial herb, is unusual for containing a high concentration of oxalic acid. Its main use in the West is as a tart stand-in for fruit, so I describe it in the next chapter (p. 367).

Sea Beans Sea beans are the small, fleshy stems and branches of salt-tolerant and salty seacoast plants in the genus Sea beans are the small, fleshy stems and branches of salt-tolerant and salty seacoast plants in the genus Salicornia, Salicornia, which is in the beet family. They are known under many other names, including samphire (a name they share with a seacoast plant in the carrot family), gla.s.swort, pick-leweed, and poussepierre. Young plants are crisp and tender and can be eaten raw or briefly blanched for their fresh, briny flavor; older ones can be cooked or steamed with seafood to intensify the sea aroma. which is in the beet family. They are known under many other names, including samphire (a name they share with a seacoast plant in the carrot family), gla.s.swort, pick-leweed, and poussepierre. Young plants are crisp and tender and can be eaten raw or briefly blanched for their fresh, briny flavor; older ones can be cooked or steamed with seafood to intensify the sea aroma.

Sprouts Sprouts are seedlings, newborn plants just an inch or so long, and are mainly stem, which elongates to push the first set of leaves aboveground into the sunlight. Of course these infantile stems are tender and not at all fibrous; they're usually eaten raw or very briefly cooked. Many different plants are germinated to make edible sprouts, but most of them come from a handful of families: the beans (mung and soy, alfalfa), the grains (wheat, corn), the cabbage family (cress, broccoli, mustard, radish), the onion family (onions, chives). Because seedlings are so vulnerable, they're sometimes protected with strong chemical defenses. In alfalfa sprouts, the defenses include the toxic amino acid canavanine (p. 259); in broccoli sprouts, the defenses are sulforaphanes, a kind of isothiocyanate (p. 321) that appears to help prevent the development of cancer. Because the wet, warm conditions of sprout production also favor the growth of microbes, raw sprouts are frequently a cause of food poisoning. They should be bought as fresh as possible and kept refrigerated, and are safest when cooked thoroughly. Sprouts are seedlings, newborn plants just an inch or so long, and are mainly stem, which elongates to push the first set of leaves aboveground into the sunlight. Of course these infantile stems are tender and not at all fibrous; they're usually eaten raw or very briefly cooked. Many different plants are germinated to make edible sprouts, but most of them come from a handful of families: the beans (mung and soy, alfalfa), the grains (wheat, corn), the cabbage family (cress, broccoli, mustard, radish), the onion family (onions, chives). Because seedlings are so vulnerable, they're sometimes protected with strong chemical defenses. In alfalfa sprouts, the defenses include the toxic amino acid canavanine (p. 259); in broccoli sprouts, the defenses are sulforaphanes, a kind of isothiocyanate (p. 321) that appears to help prevent the development of cancer. Because the wet, warm conditions of sprout production also favor the growth of microbes, raw sprouts are frequently a cause of food poisoning. They should be bought as fresh as possible and kept refrigerated, and are safest when cooked thoroughly.

Leaves: Lettuces, Cabbages, and Others Leaves are the quintessential vegetable. They're usually the most prominent and abundant parts of a plant, and they're nutritious enough that many of our primate relatives eat little else. The salad of raw greens is a truly primeval dis.h.!.+ People also cook and eat the leaves of many different plants, from weeds to root and fruit crops. In temperate regions, nearly all the tender leaves of spring are edible, and were traditionally a welcome harbinger of the new crops to come after winter's scarcity; in northeast Italy, for example, pistic pistic is a springtime collection of more than 50 different wild greens boiled and then sauteed together. is a springtime collection of more than 50 different wild greens boiled and then sauteed together.

Because they're thin and broad, leaves both edible (lettuce, cabbage, grape) and inedible (banana, fig, bamboo) are used as wrappers to contain, protect, and aromatize fillings of meat, fish, grains, and other foods. They're often blanched first to make the leaves flaccid and pliable.

Though many leaf vegetables have distinctive flavors, most of them share a common, fresh aroma note referred to as "green" or "gra.s.sy." This comes from particular molecules that are 6 carbon atoms long - "leaf alcohol" (hexanol) and "leaf aldehyde" (hexa.n.a.l) - and that are produced when leaves are cut or crushed. The cell damage frees enzymes that break up the long fatty-acid carbon chains in the membranes of the chloroplasts (p. 261). Cooking inactivates the enzymes and causes their products to react with other molecules, so the fresh green note fades and other aromas become more prominent.

The Lettuce Family: Lettuces, Chicories, Dandelion Greens The lettuce family, or the Compositae, is the second largest family of flowering plants, and yet it contributes only a few food plants. The most prominent are lettuce and its relatives, the primary components of our raw salads.

Preparing SaladsEven though salads of raw greens don't require cooking, they do require care in the preparation. Start with good ingredients: fresh young leaves are the least fibrous and have the most delicate flavor, while old overgrown lettuces can taste almost rubbery. If the leaves need to be divided into smaller pieces, this should be done with the least possible physical pressure, which can crush cells and initiate the development of off-flavors and darkened patches. Cutting with a sharp knife is generally the most effective method; tearing by hand requires squeezing, which may damage tender leaves. The greens should be well rinsed in several changes of water to remove grit, soil, and other surface contamination. Soaking them for a while in ice water will fill their cells with any water they've lost, making them turgid and crisp. Dry the greens as thoroughly as possible, so that the dressing will coat the leaves without being diluted. Thick, viscous dressings are slower to run off the leaf surface than thin, runny ones. A simple vinaigrette dressing (p. 637) can be made more viscous by chilling it in the freezer.Oil-based dressings like vinaigrettes should be added only at the last minute, because oil readily wets the waxy leaf cuticle, percolates through the empty s.p.a.ces within, and soon makes the leaf dark and sodden. Water-based cream dressings are better for greens that need to be dressed well in advance of eating.

Lettuces: Nonbitter Greens Today's mild, widely popular lettuces, varieties of the species Today's mild, widely popular lettuces, varieties of the species Lactuca sativa, Lactuca sativa, derive from an inedibly bitter weedy ancestor, derive from an inedibly bitter weedy ancestor, L. serriola, L. serriola, that grew in Asia and the Mediterranean and has been under cultivation and improvement for 5,000 years. Lettuce seems to be represented in some ancient Egyptian art, and was certainly enjoyed by the Greeks and by the Romans, who had several varieties and ate them cooked as well as raw in salads at the beginning or end of the meal. The first syllable of its Latin name, that grew in Asia and the Mediterranean and has been under cultivation and improvement for 5,000 years. Lettuce seems to be represented in some ancient Egyptian art, and was certainly enjoyed by the Greeks and by the Romans, who had several varieties and ate them cooked as well as raw in salads at the beginning or end of the meal. The first syllable of its Latin name, lac, lac, means "milk," and refers to the defensive white latex that oozes from the freshly cut base. Though lettuce is now mostly eaten raw in the West, in Asia it's often shredded and cooked. This can be a good use for the older, tougher leaves sometimes found on supermarket lettuces. means "milk," and refers to the defensive white latex that oozes from the freshly cut base. Though lettuce is now mostly eaten raw in the West, in Asia it's often shredded and cooked. This can be a good use for the older, tougher leaves sometimes found on supermarket lettuces.

There are several broad groups of lettuce varieties, each with a characteristic growth form and texture (see box below). Most lettuces have a similar taste, though some red-leaf lettuces are noticeably astringent thanks to their anthocyanin pigments. Generally, varieties whose leaves are s.h.i.+elded from sunlight by the formation of a head offer much lower levels of vitamins and antioxidants. The pale, watery crisphead variety known as iceberg triumphed in the United States due to a combination of its durability in s.h.i.+pping and storage - it brought lettuce to the American table year-round in the 1920s - and its refres.h.i.+ng, crunchy-wet texture. Head lettuces respire more slowly and so keep better than leaf lettuces; both keep significantly longer at 32F/0C than at 40F/4C. There's also a type known as stem lettuce, or celtuce; it's especially popular in Asia for its prominent and crisp stalk, which is stripped of its small leaves, peeled, sliced, and cooked. Stem lettuce and the solid core of leaf lettuces are sometimes even candied.

Chicories and Endives: Bitterness Under Control The original intense bitterness of lettuce, which came from a terpene compound called lactucin and its relatives, has been bred out of the cultivated forms. But a number of close lettuce relatives are cultivated and included in salads or cooked on their own especially to provide a civilized dose of bitterness. These are plants in the genus The original intense bitterness of lettuce, which came from a terpene compound called lactucin and its relatives, has been bred out of the cultivated forms. But a number of close lettuce relatives are cultivated and included in salads or cooked on their own especially to provide a civilized dose of bitterness. These are plants in the genus Cichorium, Cichorium, which include endive, escarole, chicory, and radicchio. Growers go to a lot of trouble to control their bitterness. Open rosettes of escaroles and endives are often tied into an artificial head to keep the inner leaves in the dark and relatively mild. And popular "Belgian endive," also known as which include endive, escarole, chicory, and radicchio. Growers go to a lot of trouble to control their bitterness. Open rosettes of escaroles and endives are often tied into an artificial head to keep the inner leaves in the dark and relatively mild. And popular "Belgian endive," also known as witloof witloof ("white-head"), is a double-grown, slightly bitter version of an otherwise very bitter chicory. The plant is grown from seed in the spring, defoliated and dug up in the fall, and the taproot with its nutrient reserves kept in cold storage. The root is then either replanted indoors and kept covered with soil and sand as it leafs out, or else it's grown hydroponically in the dark. The root takes about a month to develop a fist-sized head of white to pale green leaves, with a delicate flavor and crunchy yet tender texture. This delicacy is easily lost. Exposing the heads to light in the market will induce greening and bitterness in the outer leaves, and the flavor becomes harsh. ("white-head"), is a double-grown, slightly bitter version of an otherwise very bitter chicory. The plant is grown from seed in the spring, defoliated and dug up in the fall, and the taproot with its nutrient reserves kept in cold storage. The root is then either replanted indoors and kept covered with soil and sand as it leafs out, or else it's grown hydroponically in the dark. The root takes about a month to develop a fist-sized head of white to pale green leaves, with a delicate flavor and crunchy yet tender texture. This delicacy is easily lost. Exposing the heads to light in the market will induce greening and bitterness in the outer leaves, and the flavor becomes harsh.

Greens from the Lettuce FamilyLactuca sativa: nonbitter lettuces nonbitter lettucesLoose-leaf varieties: open cl.u.s.ter of leavesb.u.t.ter varieties: open cl.u.s.ter of soft, tender leaves, small midribsBatavian varieties: semi-open cl.u.s.ter of crisp, dense leavesCos, Romaine varieties: loose head of elongated large leaves, prominent midribsCrisphead varieties: large, tightly wrapped heads of brittle, crunchy leavesCichorium intybus: bitter chicories bitter chicoriesChicory: open cl.u.s.ter of prominent stems and leavesBelgian "endive," witloof: tight elongated head of blanched crisp leavesRadicchio: tight round to elongated head of red leavesPuntarelle: open cl.u.s.ter of prominent narrow stems and leavesCichorium endivia: bitter endives bitter endivesCurly endive: open cl.u.s.ter of curly leavesFrisee: open cl.u.s.ter of finely cut, frizzy leavesEscarole: open cl.u.s.ter of moderately broad leavesThe Cabbage Family: Relations.h.i.+ps and PungenciesBotanical nomenclature is constantly evolving, especially in complicated groups like the cabbage family. Though particular names may change, the broad relations.h.i.+ps shown here seem secure.Mediterranean originsBra.s.sica oleraceaCabbage (var. capitata capitata)Portuguese cabbage (var. tronchuda tronchuda)Kale, collards (var. acephala acephala)Broccoli (var. italica italica)Cauliflower (var. botrytis botrytis)Brussels sprouts (var. gemmifera gemmifera)Kohlrabi (var. gongylodes gongylodes)Mustard, black: Bra.s.sica nigra Bra.s.sica nigraMustard, white: Sinapis alba Sinapis albaRocket; arugula: Eruca sativa, Diplotaxis Eruca sativa, Diplotaxis species speciesWatercress: Nasturtium Nasturtium species speciesGarden cress: Lepidium Lepidium species speciesUpland, winter cress: Barbarea Barbarea species speciesNasturtium: Tropaeolum Tropaeolum species speciesGarlic mustard: Alliaria Alliaria species speciesCentral Asian originsBra.s.sica rapaTurnip (var. rapifera rapifera)Broccoli rabe, broccoletti di rape (var. rapifera rapifera)Chinese cabbage, bok choy (var. chinensis chinensis)Chinese cabbage, napa (var. pekinensis pekinensis)Tatsoi (var. narinosa narinosa)Mizuna, mibuna (var. nipposinica nipposinica)Chinese kale/broccoli, gai lan: Bra.s.sica oleracea Bra.s.sica oleracea var. var. alboglabra alboglabra Radish: Radish: Rapha.n.u.s sativus Rapha.n.u.s sativusHorseradish: Armoracia rusticana Armoracia rusticanaRecent HybridsAccidentalRutabaga, canola: Bra.s.sica napus Bra.s.sica napus ( (rapa x x oleracea oleracea)Brown mustard, mustard greens: Bra.s.sica juncea Bra.s.sica juncea ( (rapa x x nigra nigra)Ethiopian mustard: Bra.s.sica carinata Bra.s.sica carinata ( (oleracea x x nigra nigra)IntentionalBroccolini: Bra.s.sica oleracea Bra.s.sica oleracea x x alboglabra alboglabra

Relative Amounts of Sulfur Pungency Precursors

Brussels sprouts

35 35.

Green cabbage

26 26.

Broccoli

17 17.

White cabbage

15 15.

Horseradish

11 11.

Red cabbage

10 10.

Radish

7 7.

Chinese cabbage

3 3.

Cauliflower

2 2.

Salads of bitter greens are often accompanied by a salty dressing or other ingredients; salt not only balances the bitterness, but actually suppresses our perception of bitterness.

Dandelion Greens The dandelion ( The dandelion (Taraxic.u.m officinale) seems to be found naturally on all continents, although most cultivated varieties are native to Eurasia. It's occasionally grown on a small scale, and has been gathered from the wild (or the back-yard) since prehistory. The plant is a perennial, so if its taproot is left intact, it will give a rosette of leaves repeatedly. The bitter leaves are often blanched before eating to make them more palatable.

The Cabbage Family: Cabbage, Kale, Brussels Sprouts, and Others Like the onion family, the cabbage family is a group of formidable chemical warriors with strong flavors. It's also a uniquely protean family. From two weedy natives of the Mediterranean and central Asia, we have managed to develop more than a dozen major crops of very different kinds: some leaves, some flowers, some stems, some seeds. Then there are a dozen or more relatives, notably the radishes and mustards (see chapter 8 for the spicy ones), and crosses between species: altogether a rich and ongoing collaboration between nature's inventiveness and our own! Beyond the cabbage family itself, some of its distant botanical relatives share elements of its biochemistry and therefore its flavor; these include capers and papayas (pp. 409, 381).

The Flavor Chemistry of the Cabbage Family Like onions, cabbages and their relatives stockpile two kinds of defensive chemicals in their tissues: flavor precursors, and enzymes that act on the precursors to liberate the reactive flavors. When the plant's cells are damaged, the two stockpiles are mixed, and the enzymes start a chain of reactions that generates bitter, pungent, and strong-smelling compounds. The special cabbage-family system is effective enough to have inspired a notorious man-made version, the mustard gas of World War I. And the cabbage family turns out to have parts of the onion defensive system (p. 310) as well; these contribute some sulfur aromatics to the overall family flavor. Like onions, cabbages and their relatives stockpile two kinds of defensive chemicals in their tissues: flavor precursors, and enzymes that act on the precursors to liberate the reactive flavors. When the plant's cells are damaged, the two stockpiles are mixed, and the enzymes start a chain of reactions that generates bitter, pungent, and strong-smelling compounds. The special cabbage-family system is effective enough to have inspired a notorious man-made version, the mustard gas of World War I. And the cabbage family turns out to have parts of the onion defensive system (p. 310) as well; these contribute some sulfur aromatics to the overall family flavor.

The stockpiled defensive precursors in the cabbage family are called glucosinolates. glucosinolates. They differ from the onion precursors in containing not only sulfur, but also nitrogen, so they and their immediate flavor products, mainly the They differ from the onion precursors in containing not only sulfur, but also nitrogen, so they and their immediate flavor products, mainly the isothiocyanates, isothiocyanates, have distinctive qualities. Some of the flavor precursors and products are very bitter, and some have significant effects on our metabolism. Particular isothiocyanates interfere with the proper function of the thyroid gland and can cause it to enlarge if the diet is poor in iodine. But others help protect against the development of cancer by fine-tuning our system for disposing of foreign chemicals. This is the case for substances in broccoli and broccoli sprouts. have distinctive qualities. Some of the flavor precursors and products are very bitter, and some have significant effects on our metabolism. Particular isothiocyanates interfere with the proper function of the thyroid gland and can cause it to enlarge if the diet is poor in iodine. But others help protect against the development of cancer by fine-tuning our system for disposing of foreign chemicals. This is the case for substances in broccoli and broccoli sprouts.

A given vegetable will contain a number of different precursor glucosinolates, and the combinations are characteristic. This is why cabbage, brussels sprouts, broccoli, and mustard greens have similar but distinctive flavors. The chemical defensive system is most active - and the flavor strongest - in young, actively growing tissues: the center of brussels sprouts, for example, and portions of the cabbage core, which are twice as active as the outer leaves. Growing conditions have a strong influence on the amounts of flavor precursors the plant stockpiles. Summer temperatures and drought stress increase them, while the cold, wetness, and dim sunlight of autumn and winter reduce them. Autumn and winter vegetables are usually milder.

The Effects of Chopping Different preparation and cooking methods give different flavor balances in cabbage relatives. It's been found, for example, that simply chopping cabbage - for making coleslaw, for example - increases not only the liberation of flavor compounds from precursors, but also increases the production of the precursors! And if the chopped cabbage is then dressed with an acidic sauce, some pungent products increase sixfold. (Soaking the chopped cabbage in cold water will leach out most of the flavor compounds formed by chopping, at the same time that it hydrates the leaves and makes them crisper.) When cabbages and their relatives are fermented to make sauerkraut and other pickles, nearly all of the flavor precursors and their products are transformed into less bitter, less pungent substances. Different preparation and cooking methods give different flavor balances in cabbage relatives. It's been found, for example, that simply chopping cabbage - for making coleslaw, for example - increases not only the liberation of flavor compounds from precursors, but also increases the production of the precursors! And if the chopped cabbage is then dressed with an acidic sauce, some pungent products increase sixfold. (Soaking the chopped cabbage in cold water will leach out most of the flavor compounds formed by chopping, at the same time that it hydrates the leaves and makes them crisper.) When cabbages and their relatives are fermented to make sauerkraut and other pickles, nearly all of the flavor precursors and their products are transformed into less bitter, less pungent substances.

The Effects of Heat Heating cabbages and their friends has two different effects. Initially the temperature rise within the tissue speeds the enzyme activity and flavor generation, with maximum activity at around 140F/60C. The enzymes stop working altogether somewhere short of the boiling point. If the enzymes are quickly inactivated by plunging the vegetables into abundant boiling water, then many of the flavor precursor molecules will be left intact. This isn't always desirable: cooking some mustard greens quickly, for example, minimizes their hot pungency but preserves the intense bitterness of their pungency precursors. Boiling in a large excess of water leaches flavor molecules out into the water, and produces a milder flavor than does stir-frying or steaming. If the cooking period is prolonged, then the constant heat gradually transforms the flavor molecules. Eventually the sulfur compounds end up forming trisulfides, which acc.u.mulate and are mainly responsible for the strong and lingering smell of overcooked cabbage. Prolonged cooking makes members of the onion family more sweet and mellow, but the cabbage family gets more overbearing and unpleasant. Heating cabbages and their friends has two different effects. Initially the temperature rise within the tissue speeds the enzyme activity and flavor generation, with maximum activity at around 140F/60C. The enzymes stop working altogether somewhere short of the boiling point. If the enzymes are quickly inactivated by plunging the vegetables into abundant boiling water, then many of the flavor precursor molecules will be left intact. This isn't always desirable: cooking some mustard greens quickly, for example, minimizes their hot pungency but preserves the intense bitterness of their pungency precursors. Boiling in a large excess of water leaches flavor molecules out into the water, and produces a milder flavor than does stir-frying or steaming. If the cooking period is prolonged, then the constant heat gradually transforms the flavor molecules. Eventually the sulfur compounds end up forming trisulfides, which acc.u.mulate and are mainly responsible for the strong and lingering smell of overcooked cabbage. Prolonged cooking makes members of the onion family more sweet and mellow, but the cabbage family gets more overbearing and unpleasant.

Food Words: Cabbage, Kale, Collards, Cauliflower Cabbage, Kale, Collards, CauliflowerSeveral vegetables in the cabbage family, kale, collards, kale, collards, and and cauliflower, cauliflower, have names that derive from the Latin word have names that derive from the Latin word caulis, caulis, meaning "stem" or "stalk," the part of the plant from which the edible portions emerge. meaning "stem" or "stalk," the part of the plant from which the edible portions emerge. Cabbage Cabbage itself comes from the Latin itself comes from the Latin caput, caput, meaning "head": it's the one form in which the stem is reduced to a short stub, and the leaves form a head around it. meaning "head": it's the one form in which the stem is reduced to a short stub, and the leaves form a head around it.

Thanks to the fact that they share some enzyme systems, mixtures of the onion and cabbage families can produce surprising effects. Add bits of raw scallion to some cooked and therefore nonpungent mustard greens, and the scallion enzymes will transform heat-stable mustard precursors into pungent products: so the bits of scallion taste more mustardy than the greens themselves!

Cabbage, Kale, Collards, Brussels Sprouts The original wild cabbage is native to the Mediterranean seaboard, and this salty, sunny habitat accounts for the thick, succulent, waxy leaves and stalks that help make these plants so hardy. It was domesticated around 2,500 years ago, and thanks to its tolerance of cold climates, it became an important staple vegetable in Eastern Europe. The practice of pickling it appears to have originated in China. The original wild cabbage is native to the Mediterranean seaboard, and this salty, sunny habitat accounts for the thick, succulent, waxy leaves and stalks that help make these plants so hardy. It was domesticated around 2,500 years ago, and thanks to its tolerance of cold climates, it became an important staple vegetable in Eastern Europe. The practice of pickling it appears to have originated in China.

Collards, kale, and Portuguese tronchuda cabbage resemble wild cabbage in bearing separate leaves along a fairly short main stalk; tronchuda has especially ma.s.sive midribs. Cultivated cabbage forms a large head of closely nested leaves around the tip of the main stalk. There are many varieties, some dark green, some nearly white, some red with anthocyanin pigments, some deeply ridged, and some smooth. In general, open-leaved plants acc.u.mulate more vitamins C and A and antioxidant carotenoids than heading varieties whose inner leaves never see the light of day. Heading cabbages often contain more sugar, and store well for months after harvest.

Brussels sprouts come from a cabbage variant that develops small, numerous heads along a greatly elongated central stalk. It may have been developed in northern Europe in the 15th century, but clear evidence for its existence only dates from the 18th. For many people who are sensitive to bitter tastes, brussels sprouts are simply too bitter to eat. They contain very high levels of glucosinolates. One of the major types (sinigrin, also the major mustard precursor) tastes bitter itself but produces a nonbitter thiocyanate, while the other (progoitrin) is nonbitter but produces a bitter thiocyanate. So whether we cook sprouts rapidly to minimize the production of thiocyanates, or slowly to transform all of the glucosinolates, the result is still bitter. Since these flavor components are concentrated in the center of the sprout, it helps to halve the sprouts and cook them in a large pot of boiling water, which will leach out both precursors and products.

Some vegetables in the remarkably various cabbage family. Center Center : Kale leaf. : Kale leaf. To its right and clockwise: To its right and clockwise: The swollen stem of kohlrabi, the terminal bud of head cabbage, the lateral buds of brussels sprouts, the flowering stalk of broccoli, and cauliflower, a ma.s.s of undeveloped flower stalks. The swollen stem of kohlrabi, the terminal bud of head cabbage, the lateral buds of brussels sprouts, the flowering stalk of broccoli, and cauliflower, a ma.s.s of undeveloped flower stalks.

Rocket, Cress, Mustard Greens, Ethiopian Mustard Rocket (or Italian arugula, both from the Latin root Rocket (or Italian arugula, both from the Latin root roc roc meaning "harsh, rough") is the name given to several different plants and their leaves, all small, weedy cabbage relatives from the Mediterranean region that are especially pungent, with a full, almost meaty flavor built from various aldehydes, including almond-essence benzaldehyde. They're frequently used to enliven a salad of mixed greens, but are also pureed into a brilliant green sauce or put on pizzas. Even the briefest cooking will inactivate their protection-generating enzymes and turn them into tame greens. Some large-leaved varieties are quite mild. Like rocket, the different forms of cress - water, garden, winter - are small-leaved and pungent, usually used as a garnish or as a refres.h.i.+ng counterpoint to a rich meat. Their close relative, the window box nasturtium plant, sometimes lends its slightly pungent flower for a garnish; the more peppery flower buds are also used. meaning "harsh, rough") is the name given to several different plants and their leaves, all small, weedy cabbage relatives from the Mediterranean region that are especially pungent, with a full, almost meaty flavor built from various aldehydes, including almond-essence benzaldehyde. They're frequently used to enliven a salad of mixed greens, but are also pureed into a brilliant green sauce or put on pizzas. Even the briefest cooking will inactivate their protection-generating enzymes and turn them into tame greens. Some large-leaved varieties are quite mild. Like rocket, the different forms of cress - water, garden, winter - are small-leaved and pungent, usually used as a garnish or as a refres.h.i.+ng counterpoint to a rich meat. Their close relative, the window box nasturtium plant, sometimes lends its slightly pungent flower for a garnish; the more peppery flower buds are also used.

Mustard greens are leaves from varieties of brown mustard (B. juncea) that have been selected for their foliage rather than their seeds. Their texture is more delicate than that of cabbage. They're often quite pungent in the fas.h.i.+on of seed mustard, but are usually cooked, which may leave them mild and cabbage-like or intensely bitter, depending on the variety. Ethiopian mustard, a natural hybrid between the cabbage and mustard groups, probably arose in northeastern Africa, where the fast-growing young leaves are eaten both raw and lightly cooked. An improved variety developed in the United States is called texsel greens.

Asian Cabbages and Relatives The several very different forms of Chinese cabbage, including bok choy, napa, and tatsoi, all stem from the same species of The several very different forms of Chinese cabbage, including bok choy, napa, and tatsoi, all stem from the same species of Bra.s.sica Bra.s.sica that gave us the turnip. that gave us the turnip. B. rapa B. rapa is one of the oldest cultivated plants, possibly bred first for its seeds, and now among the most important vegetables in Asia. The larger modern forms are mainly elongated heads weighing up to 10 lb/4.5 kg, and are distinguished from European cabbages by their prominent white midribs, less prominent light green leaves, and mildness. Their smaller relatives mizuna and mibuna form low, spreading clumps of long, narrow leaves, those of mizuna being finely divided and feathery. Tatsoi makes a rosette of rounded leaves. These small leaves do well as additions to Western salads; they tolerate storage and dressings better than more delicate lettuces. is one of the oldest cultivated plants, possibly bred first for its seeds, and now among the most important vegetables in Asia. The larger modern forms are mainly elongated heads weighing up to 10 lb/4.5 kg, and are distinguished from European cabbages by their prominent white midribs, less prominent light green leaves, and mildness. Their smaller relatives mizuna and mibuna form low, spreading clumps of long, narrow leaves, those of mizuna being finely divided and feathery. Tatsoi makes a rosette of rounded leaves. These small leaves do well as additions to Western salads; they tolerate storage and dressings better than more delicate lettuces.

Spinach and Chard Spinach Spinach ( Spinach (Spinacia oleracea) is a member of the beet family that was domesticated in central Asia, and is most productive in the cool seasons (heat and long days cause it to go to seed while it has relatively few leaves). In the late Middle Ages the Arabs brought it to Europe, where it soon displaced its smaller-leaved relatives orache and lamb's-quarters, as well as amaranth and sorrel. In the cla.s.sic cuisine of France, spinach was likened to cire-vierge, cire-vierge, or virgin beeswax, capable of receiving any impression or effect, while most other vegetables imposed their taste upon the dish. Today it's the most important leaf vegetable apart from lettuce, valued for its rapid growth, mild flavor, and tender texture when briefly cooked. (Some varieties are tender when raw, while thick-leaved varieties are chewy and less suitable for salads.) When cooked, its volume is reduced by about three-quarters. Spinach has a high content of potentially troublesome oxalates (p. 259), but it remains an excellent source of vitamin A as well as of phenolic antioxidants and compounds that reduce potential cancer-causing damage to our DNA. Folic acid was first purified from spinach, which is our richest source of this important vitamin (p. 255). or virgin beeswax, capable of receiving any impression or effect, while most other vegetables imposed their taste upon the dish. Today it's the most important leaf vegetable apart from lettuce, valued for its rapid growth, mild flavor, and tender texture when briefly cooked. (Some varieties are tender when raw, while thick-leaved varieties are chewy and less suitable for salads.) When cooked, its volume is reduced by about three-quarters. Spinach has a high content of potentially troublesome oxalates (p. 259), but it remains an excellent source of vitamin A as well as of phenolic antioxidants and compounds that reduce potential cancer-causing damage to our DNA. Folic acid was first purified from spinach, which is our richest source of this important vitamin (p. 255).

A number of unrelated but tender-leafed plants are called spinach. Malabar spinach is an Asian climber, Basella alba, Basella alba, notable for its heat tolerance and the mucilaginous texture of its leaves, which may be green or red. New Zealand spinach is a relative of the succulent ice plant (also eaten!), notable for its heat tolerance and the mucilaginous texture of its leaves, which may be green or red. New Zealand spinach is a relative of the succulent ice plant (also eaten!), Tetragonia tetragonioides, Tetragonia tetragonioides, productive in hot weather but thick-leaved and best when cooked. Water spinach is an Asian relative of the sweet potato, productive in hot weather but thick-leaved and best when cooked. Water spinach is an Asian relative of the sweet potato, Ipomoea aquatica, Ipomoea aquatica, with elongated leaves and crunchy, hollow stems that are good at taking up sauce. with elongated leaves and crunchy, hollow stems that are good at taking up sauce.

Chard Chard is the name given to varieties of the beet, Chard is the name given to varieties of the beet, Beta vulgaris, Beta vulgaris, that have been selected for thick, meaty leaf stalks (subspecies that have been selected for thick, meaty leaf stalks (subspecies cicla cicla) rather than their roots. The beet is a distant relative of spinach, and its leaves - including ordinary, thin-midribbed beet greens - also contain oxalates. Chard stalks and leaf veins can be colored brilliant yellow, orange, and crimson by the same betain pigments that color the roots, which are water-soluble and stain cooking liquids and sauces. Some of the recently revived colored varieties are heirlooms that go back to the 16th century.

Miscellaneous Leafy Greens Here are notes on a select handful of the many other greens that find their way to the table.

Amaranth Amaranth (species of Amaranth (species of Amaranthus Amaranthus), sometimes called Chinese spinach and other names, has been enjoyed since ancient times in both Europe and Asia. Its tender, earthy-flavored leaves are rich in vitamin A, but also in oxalates: two to three times more than spinach, for example. Boiling in copious water will remove some of them.

Grape Leaves Grape leaves are best known in pickled form as the wrappers for Greek dolmades. They are more delicate and delicious when blanched fresh. Grape leaves are distinctly tart from their large store of malic and tartaric acids. Grape leaves are best known in pickled form as the wrappers for Greek dolmades. They are more delicate and delicious when blanched fresh. Grape leaves are distinctly tart from their large store of malic and tartaric acids.

Mache Mache, also known as lamb's lettuce or corn salad ( Mache, also known as lamb's lettuce or corn salad (Valerianella locusta and and V. eriocarpa V. eriocarpa), has small, tender, slightly mucilaginous leaves and a distinctive, complex, fruity-flowery aroma (from various esters, linalool, mushroomy octenol, and lemony citronellol), which make it a popular addition or alternative to a lettuce salad in Europe.