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Food Words: Date, Pomegranate Date, PomegranateDate comes from the Greek word for "finger," comes from the Greek word for "finger," daktulos, daktulos, which the elongated fruits resemble. which the elongated fruits resemble. Pomegranate Pomegranate comes from medieval French, and is a combination of Latin roots meaning "apple" and "grainy" or "seedy." comes from medieval French, and is a combination of Latin roots meaning "apple" and "grainy" or "seedy."
The walls of the fig fruit contain latex vessels that carry a protein-digesting enzyme, ficin, and tannin cells that contribute astringency. Figs are remarkable for containing very large amounts of phenolic compounds, some of them antioxidants, and large amounts of calcium for a fruit. When ripe, figs have a unique aroma that comes mainly from spicy phenolic compounds and a flowery terpene (linalool).
Jujube Jujubes, also known as Chinese dates, are the fruits of Jujubes, also known as Chinese dates, are the fruits of Ziziphus jujuba, Ziziphus jujuba, a tree native to central Asia. They do bear some resemblance to dates, as do the version known in India as the ber ( a tree native to central Asia. They do bear some resemblance to dates, as do the version known in India as the ber (Z. mauritania). Both trees tolerate heat and drought and are now grown in arid regions throughout the world. Jujubes are small, somewhat dry and spongy, more sweet than tart. They're an excellent source of vitamin C, containing more than double the amount in an equal weight of oranges. They're eaten fresh, dried, pickled, in rice-based cakes, and fermented into alcoholic drinks.
Pomegranate Pomegranates are fruits of the shrubby tree Pomegranates are fruits of the shrubby tree Punica granatum, Punica granatum, a native of the arid and semiarid regions of the Mediterranean and western Asia; the finest varieties are said to grow in Iran. With their dull, dry rind surrounding two layered chambers of translucent, ruby-like fruitlets (there are also pale and yellow varieties), they figured very early in mythology and art. Pomegranate-shaped goblets have been found in prehistoric Troy, and in Greek myth it was a pomegranate that tempted Persephone and kept her in the underworld. Pomegranates are very sweet, fairly tart, and often astringent thanks to their strongly pigmented juice well-stuffed with anthocyanins and related phenolic antioxidants. Juice manufactured by crus.h.i.+ng whole fruits is much more tannic than the fruitlets themselves; the rind is so rich in tannins that it was once used for tanning leather! Because each fruitlet contains a prominent seed, pomegranates are usually processed into juice, which then can be used as is or cooked down to make a syrup or "mola.s.ses," or fermented into a wine. True grenadine is pomegranate juice mixed with a hot sugar syrup. Today most commercial grenadines are synthetic. In northern India, pomegranate fruitlets are dried and ground for use as an acidifying powder. a native of the arid and semiarid regions of the Mediterranean and western Asia; the finest varieties are said to grow in Iran. With their dull, dry rind surrounding two layered chambers of translucent, ruby-like fruitlets (there are also pale and yellow varieties), they figured very early in mythology and art. Pomegranate-shaped goblets have been found in prehistoric Troy, and in Greek myth it was a pomegranate that tempted Persephone and kept her in the underworld. Pomegranates are very sweet, fairly tart, and often astringent thanks to their strongly pigmented juice well-stuffed with anthocyanins and related phenolic antioxidants. Juice manufactured by crus.h.i.+ng whole fruits is much more tannic than the fruitlets themselves; the rind is so rich in tannins that it was once used for tanning leather! Because each fruitlet contains a prominent seed, pomegranates are usually processed into juice, which then can be used as is or cooked down to make a syrup or "mola.s.ses," or fermented into a wine. True grenadine is pomegranate juice mixed with a hot sugar syrup. Today most commercial grenadines are synthetic. In northern India, pomegranate fruitlets are dried and ground for use as an acidifying powder.
The Citrus Family: Orange, Lemon, Grapefruit, and Relatives Citrus fruits are among the most important of all tree fruits. From their birthplace insouthern China, northern India, and Southeast Asia they spread throughout the subtropics and mild temperate zones of the world. Ancient trade took the citron to western Asia and the Middle East before 500 BCE BCE, and medieval crusaders brought sour oranges back with them to Europe; Genoese and Portuguese traders introduced sweet oranges around 1500, and Spanish explorers carried them to the Americas. Today, Brazil and the United States produce most of the world's oranges. Barely a century ago, oranges were special holiday treats; now much of the Western world starts its day with orange juice.
The fig. It contains small flowers within the fleshy "fruit," which is actually the swollen flower base. The fig is an inverted version of the strawberry: it surrounds rather than underlies the true tiny fruits, or achenes.
Why are citrus fruits so popular? They offer an unusual set of virtues. Above all, their peels have distinctive and strong aromas, and these may have been their original attraction, well before human selection developed varieties with sweet juices. The improved varieties do have a refres.h.i.+ng, tart to sweet-tart juice that can be extracted with little pulp. The peel is rich in gel-making pectins. And citrus fruits are also fairly robust. They're nonclimacteric, so they retain their quality for some time after harvest, and the meaty peel offers good protection against physical damage and attack by spoilage microbes.
Citrus Anatomy Each segment of a citrus fruit is a compartment of the ovary, and is stuffed with small, elongated bags called Each segment of a citrus fruit is a compartment of the ovary, and is stuffed with small, elongated bags called vesicles, vesicles, each of which contains many individual microscopic juice cells that fill with water and dissolved substances as the fruit develops. Surrounding the segments is a thick, white, spongy layer called the each of which contains many individual microscopic juice cells that fill with water and dissolved substances as the fruit develops. Surrounding the segments is a thick, white, spongy layer called the albedo, albedo, usually rich in both bitter substances and in pectin. And riding atop the albedo is the skin, a thin, pigmented layer with tiny spherical glands that create and store volatile oils. Flexing a piece of citrus peel will burst the oil glands and send a visible, aromatic - and flammable! - spray into the air. usually rich in both bitter substances and in pectin. And riding atop the albedo is the skin, a thin, pigmented layer with tiny spherical glands that create and store volatile oils. Flexing a piece of citrus peel will burst the oil glands and send a visible, aromatic - and flammable! - spray into the air.
Citrus Color and Flavor Citrus fruits owe their yellow and orange colors ( Citrus fruits owe their yellow and orange colors (orange comes ultimately from the Sanskrit word for the fruit) to a complex mixture of carotenoids, only a small portion of which has vitamin A activity. The fruit peels start out green, and in the tropics often stay that way even when the fruit ripens. In other regions, cold temperatures trigger destruction of chlorophyll in the peel, and the carotenoids become visible. Fruits of commerce are often picked green and treated with ethylene to improve their color, and coated with an edible wax to slow moisture loss. Pink and red grapefruit are colored by lycopene, and red sweet oranges by a mixture of lycopene and beta-carotene and by cryptoxanthin. The purple-red of blood oranges comes from anthocyanins. comes ultimately from the Sanskrit word for the fruit) to a complex mixture of carotenoids, only a small portion of which has vitamin A activity. The fruit peels start out green, and in the tropics often stay that way even when the fruit ripens. In other regions, cold temperatures trigger destruction of chlorophyll in the peel, and the carotenoids become visible. Fruits of commerce are often picked green and treated with ethylene to improve their color, and coated with an edible wax to slow moisture loss. Pink and red grapefruit are colored by lycopene, and red sweet oranges by a mixture of lycopene and beta-carotene and by cryptoxanthin. The purple-red of blood oranges comes from anthocyanins.
Citrus anatomy. The protective outer rind includes aromatic oil glands embedded in a bitter white pith, the albedo. Each segment, or carpel, carpel, of a citrus fruit consists of many delicate juice sacs contained within a strong membrane. of a citrus fruit consists of many delicate juice sacs contained within a strong membrane.
The taste of citrus fruits is created by a handful of substances, including citric acid (so named because it is typical of the family), sugars, and certain bitter phenolic compounds, which are usually concentrated in the albedo and peel. Citrus fruits are surprisingly rich in the savory amino acid glutamate, sometimes rivaling the tomato (oranges reach 70 milligrams per 100 grams, grapefruits 250). They contain little starch and therefore don't sweeten much after picking. Usually the blossom end of the fruit contains both more acid and more sugars, and so has a more intense taste than the stem end. Neighboring segments can also vary significantly in taste.
Citrus aroma is produced both by the oil glands in the skin and oil droplets in the juice vesicles - and these two sources are usually quite distinct. Generally the vesicle oils contain more fruity esters, and peel oil more green aldehydes and citrusy/spicy terpenes (p. 274). A few aroma compounds are shared by most citrus fruit, including generically citrusy limonene and small amounts of eggy hydrogen sulfide. In freshly made juice, the sac oil droplets gradually aggregate with the pulpy materials, and this aggregation reduces the aroma available to the taster, especially if some of the pulp is strained off.
Citrus Peel The intensely flavored citrus peel has long been used to flavor dishes (for example, dried orange peel in Sichuan cooking), and as a preparation in itself in the form of candied rind. The outer epidermis contains the aromatic oil glands, while the underlying white, spongy, pectinrich albedo usually contains protective bitter phenolic substances. Both the oil with its terpenes and the antioxidant phenolics are valuable phytochemicals (pp. 256, 257). The bitters are water-soluble, while the oils are not. Cooks can therefore leach the peel repeatedly with hot (rapid) or cold (slow) water to remove the bitter compounds, then gently cook the peel if still necessary to soften the albedo, and finally infuse it with a concentrated sugar syrup. Through all this processing the water-insoluble oils stay largely in the rind. The intensely flavored citrus peel has long been used to flavor dishes (for example, dried orange peel in Sichuan cooking), and as a preparation in itself in the form of candied rind. The outer epidermis contains the aromatic oil glands, while the underlying white, spongy, pectinrich albedo usually contains protective bitter phenolic substances. Both the oil with its terpenes and the antioxidant phenolics are valuable phytochemicals (pp. 256, 257). The bitters are water-soluble, while the oils are not. Cooks can therefore leach the peel repeatedly with hot (rapid) or cold (slow) water to remove the bitter compounds, then gently cook the peel if still necessary to soften the albedo, and finally infuse it with a concentrated sugar syrup. Through all this processing the water-insoluble oils stay largely in the rind. Marmalade, Marmalade, a sugar preserve that includes citrus peel, was originally a Portuguese fruit paste made with quince, but by the 18th century the high-pectin, readily gelled sour orange had begun to replace the quince. Marmalade made with sweet oranges doesn't gel as readily and lacks the characteristic flavor, including a bitterness that helps balance the sugar. a sugar preserve that includes citrus peel, was originally a Portuguese fruit paste made with quince, but by the 18th century the high-pectin, readily gelled sour orange had begun to replace the quince. Marmalade made with sweet oranges doesn't gel as readily and lacks the characteristic flavor, including a bitterness that helps balance the sugar.
As is true for most fruits, the skin of citrus fruits is more easily removed from the underlying tissue by briefly immersing the fruit in simmering water. Thick citrus rinds require an immersion of several minutes. Heat softens the cell-wall cement that attaches rind to fruit, and may also encourage some enzymes to begin to dissolve the cement.
Kinds of Citrus Fruits Trees in the genus Trees in the genus Citrus Citrus are wonderfully variable and p.r.o.ne to form hybrids with each other, which makes it a challenge for scientists to work out family relations.h.i.+ps. Currently it's thought that the common domesticated citrus fruits all derive from just three parents: the citron are wonderfully variable and p.r.o.ne to form hybrids with each other, which makes it a challenge for scientists to work out family relations.h.i.+ps. Currently it's thought that the common domesticated citrus fruits all derive from just three parents: the citron Citrus medica, Citrus medica, the mandarin orange the mandarin orange Citrus reticulata, Citrus reticulata, and the pummelo and the pummelo Citrus grandis. Citrus grandis. At least one offspring is relatively young: the grapefruit apparently originated in the West Indies in the 18th century as a cross between the pummelo and the sweet orange. At least one offspring is relatively young: the grapefruit apparently originated in the West Indies in the 18th century as a cross between the pummelo and the sweet orange.
Citron Perhaps the first citrus fruit to reach the Middle East around 700 Perhaps the first citrus fruit to reach the Middle East around 700 BCE BCE and the Mediterranean around 300 and the Mediterranean around 300 BCE BCE, citrons are native to the Himalayan foothills. They gave their name to the genus, and their name came in turn from their resemblance to the cone of a Mediterranean evergreen cedar (Greek kedros kedros). The several varieties have little juice, but an intensely aromatic rind that can perfume a room - citrons are used in both Asian and Jewish religious ceremonies - and that has long been candied (p. 295). In China's Sichuan province, the rind is made into a hot pickle.
Flavor Notes in Some Citrus Fruits The chemicals listed in the first five flavor headings are terpenes, which are especially characteristic of citrus fruits and some herbs and spices (p. 390).
Mandarin, or Tangerine Mandarin oranges were cultivated in ancient India and China at least 3,000 years ago. The well-known j.a.panese type, the satsuma, appeared by the 16th century, and Mediterranean types ("tangerines," from the Moroccan city of Tangier) in the 19th century. Mandarins tend to be relatively small and flat, with a reddish, easily peeled rind and a distinctive, rich aroma that has notes of thyme and Concord grape (thymol, methyl anthranilate). They're the most cold-hardy of citrus trees, yet the fruits are fairly fragile. Satsumas are seedless and commonly processed into canned segments. Mandarin oranges were cultivated in ancient India and China at least 3,000 years ago. The well-known j.a.panese type, the satsuma, appeared by the 16th century, and Mediterranean types ("tangerines," from the Moroccan city of Tangier) in the 19th century. Mandarins tend to be relatively small and flat, with a reddish, easily peeled rind and a distinctive, rich aroma that has notes of thyme and Concord grape (thymol, methyl anthranilate). They're the most cold-hardy of citrus trees, yet the fruits are fairly fragile. Satsumas are seedless and commonly processed into canned segments.
Pummelo Pummelos require the warmest growing conditions of the common citrus fruits and have been slow to spread from their home in tropical Asia, where they were cultivated in ancient times. They're large, 10 in/25 cm or more in diameter, with a relatively thick albedo layer; large, easily separated juice vesicles that burst in the mouth; thick and tough segment membranes; and an absence of the bitterness that flavors its offspring the grapefruit. Some varieties have pink-red vesicles. Pummelos require the warmest growing conditions of the common citrus fruits and have been slow to spread from their home in tropical Asia, where they were cultivated in ancient times. They're large, 10 in/25 cm or more in diameter, with a relatively thick albedo layer; large, easily separated juice vesicles that burst in the mouth; thick and tough segment membranes; and an absence of the bitterness that flavors its offspring the grapefruit. Some varieties have pink-red vesicles.
Orange Nearly three-fourths of all citrus fruit produced in the world are oranges, whose juiciness and moderate size, sweetness, and acidity make them especially versatile. They're probably an ancient hybrid between the mandarin and the pummelo, and have in turn been developed into several very different kinds of fruit. Nearly three-fourths of all citrus fruit produced in the world are oranges, whose juiciness and moderate size, sweetness, and acidity make them especially versatile. They're probably an ancient hybrid between the mandarin and the pummelo, and have in turn been developed into several very different kinds of fruit.
Navel oranges probably originated in China, but became a major commodity worldwide when a Brazilian variety arrived in the United States in 1870. The navel-like appearance of their blossom end is caused by the development of a small secondary set of segments. Navels are the ideal orange for eating fresh because they're seedless and easily peeled. However, the trees are finicky to grow, and their juice contains fewer fruity esters than the best juice varieties. And juice made from navel oranges will become noticeably bitter after about 30 minutes. This happens because when the juice cells are broken and their contents mixed, acids and enzymes convert a tasteless precursor molecule into an intensely bitter terpene compound called limonin. oranges probably originated in China, but became a major commodity worldwide when a Brazilian variety arrived in the United States in 1870. The navel-like appearance of their blossom end is caused by the development of a small secondary set of segments. Navels are the ideal orange for eating fresh because they're seedless and easily peeled. However, the trees are finicky to grow, and their juice contains fewer fruity esters than the best juice varieties. And juice made from navel oranges will become noticeably bitter after about 30 minutes. This happens because when the juice cells are broken and their contents mixed, acids and enzymes convert a tasteless precursor molecule into an intensely bitter terpene compound called limonin.
Citrus Family Relations.h.i.+ps
The Parent Species
Citron
Citrus medica Citrus medica
Mandarin, tangerine
Citrus reticulata Citrus reticulata
Pummelo
Citrus grandis Citrus grandis
Their Offspring
Sour orange
Citrus aurantium Citrus aurantium
Sweet orange
Citrus sinensis, Citrus sinensis, pummelo x mandarin(?) pummelo x mandarin(?)
Grapefruit
Citrus paradisi, Citrus paradisi, pummelo x sweet orange pummelo x sweet orange
Sour lime
Citrus aurantifolia Citrus aurantifolia
Persian/Tahiti lime
Citrus latifolia, Citrus latifolia, sour lime x citron(?) sour lime x citron(?)
Lemon
Citrus limon, Citrus limon, citron x sour lime x pummelo(?) citron x sour lime x pummelo(?)
Meyer lemon
Citrus limon, Citrus limon, lemon x mandarin or sweet orange? lemon x mandarin or sweet orange?
Modern Hybrids
Tangelo
Citrus Citrus x x tangelo, tangelo, tangerine x grapefruit tangerine x grapefruit
Tangor
Citrus Citrus x x n.o.bilis, n.o.bilis, tangerine x sweet orange tangerine x sweet orange
Common or or juice juice oranges have a smooth blossom end, generally contain seeds, and have a more adherent skin than navel oranges. Commercial orange juice is made from juice varieties with little tendency to develop limonin bitterness. The mild flavor of the juice is usually augmented by the addition of peel oils. oranges have a smooth blossom end, generally contain seeds, and have a more adherent skin than navel oranges. Commercial orange juice is made from juice varieties with little tendency to develop limonin bitterness. The mild flavor of the juice is usually augmented by the addition of peel oils.
Blood oranges have been grown in the southern Mediterranean at least since the 18th century, and may have originated there or in China. They're now the major type of orange grown in Italy. Blood oranges owe the deep maroon color of their juice to anthocyanin pigments, which develop only when night temperatures are low, in the Mediterranean autumn and winter. The pigments tend to acc.u.mulate at the blossom end and in vesicles immediately next to the segment walls, and continue to acc.u.mulate after harvest when the fruits are held in cold storage. The pigments and their phenolic precursors give blood oranges a higher antioxidant value than other oranges. The unique flavor of blood oranges combines citrus notes with a distinct raspberry-like aroma. oranges have been grown in the southern Mediterranean at least since the 18th century, and may have originated there or in China. They're now the major type of orange grown in Italy. Blood oranges owe the deep maroon color of their juice to anthocyanin pigments, which develop only when night temperatures are low, in the Mediterranean autumn and winter. The pigments tend to acc.u.mulate at the blossom end and in vesicles immediately next to the segment walls, and continue to acc.u.mulate after harvest when the fruits are held in cold storage. The pigments and their phenolic precursors give blood oranges a higher antioxidant value than other oranges. The unique flavor of blood oranges combines citrus notes with a distinct raspberry-like aroma.
Acidless oranges are grown in small numbers in north Africa, Europe, and South America, and have about a tenth the acidity - and less orange aroma - of common and navel oranges. oranges are grown in small numbers in north Africa, Europe, and South America, and have about a tenth the acidity - and less orange aroma - of common and navel oranges.
Sour oranges come from a different species than the kinds described above, and are both sour and bitter (thanks not to limonin but a related compound, neohesperidin), with an intense and distinctive peel aroma. They arrived in Spain and Portugal in the 12th century, and soon displaced quince as the main ingredient in marmalade. Sour-orange flowers are used to make orange flower water. oranges come from a different species than the kinds described above, and are both sour and bitter (thanks not to limonin but a related compound, neohesperidin), with an intense and distinctive peel aroma. They arrived in Spain and Portugal in the 12th century, and soon displaced quince as the main ingredient in marmalade. Sour-orange flowers are used to make orange flower water.
Grapefruit The grapefruit originated as a hybrid of the sweet orange and pummelo in the Caribbean in the 18th century, and is still mainly grown in the Americas. The red types owe their color to lycopene, and first appeared as chance mutations in Florida and in Texas early in the 20th century (the more recent and popular Star Ruby and Rio Red varieties were created by intentionally inducing mutations with radiation). Unlike the anthocyanin coloration of blood oranges, grapefruit lycopene requires consistent high growing temperatures to develop well, appears evenly through all the juice vesicles, and is stable to heat. The characteristic moderate bitterness is caused by a phenolic substance called naringin, whose concentration declines as the fruit ripens. Like navel oranges, grapefruits also contain a precursor of limonin, and its juice becomes bitter on standing. Some grapefruit phenolic compounds turn out to interfere with our metabolism of certain drugs, cause the drugs to persist longer in the body, and thus cause the equivalent of an overdose, so medicine labels sometimes warn against consuming grapefruit or its juice along with the medicine. (These same phenolics are now being developed into activity-boosting drug ingredients.) Grapefruits have an especially complex aroma, which includes meaty and musky sulfur compounds. The grapefruit originated as a hybrid of the sweet orange and pummelo in the Caribbean in the 18th century, and is still mainly grown in the Americas. The red types owe their color to lycopene, and first appeared as chance mutations in Florida and in Texas early in the 20th century (the more recent and popular Star Ruby and Rio Red varieties were created by intentionally inducing mutations with radiation). Unlike the anthocyanin coloration of blood oranges, grapefruit lycopene requires consistent high growing temperatures to develop well, appears evenly through all the juice vesicles, and is stable to heat. The characteristic moderate bitterness is caused by a phenolic substance called naringin, whose concentration declines as the fruit ripens. Like navel oranges, grapefruits also contain a precursor of limonin, and its juice becomes bitter on standing. Some grapefruit phenolic compounds turn out to interfere with our metabolism of certain drugs, cause the drugs to persist longer in the body, and thus cause the equivalent of an overdose, so medicine labels sometimes warn against consuming grapefruit or its juice along with the medicine. (These same phenolics are now being developed into activity-boosting drug ingredients.) Grapefruits have an especially complex aroma, which includes meaty and musky sulfur compounds.
Lime Limes are the most acidic of the citrus fruits, as much as 8% of their weight coming from citric acid. The small, seedy Mexican or Key lime, Limes are the most acidic of the citrus fruits, as much as 8% of their weight coming from citric acid. The small, seedy Mexican or Key lime, C. aurantifolia, C. aurantifolia, is the standard sour citrus fruit in the tropics, where lemons don't grow well. In western Asia it's sun-dried whole, then ground and used as an aromatic, somewhat musty acidifier. The larger, seedless, more cold-tolerant Persian or Tahiti or Bearss lime, is the standard sour citrus fruit in the tropics, where lemons don't grow well. In western Asia it's sun-dried whole, then ground and used as an aromatic, somewhat musty acidifier. The larger, seedless, more cold-tolerant Persian or Tahiti or Bearss lime, C. latifolia, C. latifolia, may be a hybrid between the true lime and citron, and is more common in the United States and Europe. Despite the general impression that limes are characteristically "lime-green," both turn pale yellow when fully ripe. They owe their distinctive limeness to pine, floral, and spicy aroma notes (from terpenes). may be a hybrid between the true lime and citron, and is more common in the United States and Europe. Despite the general impression that limes are characteristically "lime-green," both turn pale yellow when fully ripe. They owe their distinctive limeness to pine, floral, and spicy aroma notes (from terpenes).
Lemon Lemons may have originated as a two-step hybrid, the first (citron crossed with lime) arising in the area of northwest India and Pakistan, the second ([citron crossed with lime] crossed with pummelo) in the Middle East. Lemons arrived in the Mediterranean around 100 Lemons may have originated as a two-step hybrid, the first (citron crossed with lime) arising in the area of northwest India and Pakistan, the second ([citron crossed with lime] crossed with pummelo) in the Middle East. Lemons arrived in the Mediterranean around 100 CE CE, were planted in orchards in Moorish Spain by 400, and are now mainly cultivated in subtropical regions. They're valued for their acidity, often 5% of the juice, and their fresh, bright aroma, which is the base for many popular fresh and bottled drinks. There are many varieties of true lemon, and also a couple of further hybrids. The large, coa.r.s.e Ponderosa variety is probably a lemon-citron cross, and the Meyer lemon, a thin-skinned, less acid version brought to California in the early 20th century, is probably a cross between the lemon and either orange or mandarin, with a distinctive flavor due in part to a thyme note (from thymol). Lemons are generally "cured" for better shelf life; they're picked green and held in controlled conditions for several weeks, where their skin yellows, thins, and develops a waxy surface, and the juice vesicles enlarge.
The preserved lemons of northern Africa have recently become more widely appreciated as a condiment. They're made by cutting and salting lemons and letting them ferment for some weeks. The growth of bacteria and yeasts softens the rind and changes their aroma from bright and sharp to rich and rounded. Short versions of the process - for example, freezing and thawing the lemons to speed salt penetration, then salting for a few hours or days - will bring about some chemical changes as the oil glands are disrupted and their contents mix with other substances, but not the full flavor development of fermentation.