by Rebecca Rupp
Along with the color change, ripening involves marked changes in texture and taste. The fruit softens due to the activity of the enzymes pectinesterase and polygalacturonase, which convert the insoluble cell-wall pectins to soluble form. In the unripe fruit, the insoluble pectins act to strengthen cell walls and to bind adjacent cells together; soluble pectins, on the other hand, weaken the whole structure and allow the cells to separate easily when bitten. In the absence of pectinesterase and polygalacturonase, tomatoes would have to be gnawed. There are some tomato mutants that suffer from just that: one of these, designated Neverripe, produces only miniscule amounts of the required enzymes and softens extremely slowly. Understandably, scientists are more interested in it than gardeners are.
Finally, ripening involves the development of true tomato taste, the quality we all fantasize about, but don’t get, from the winterbound Safeway, Shop ‘n Save, or Piggly-Wiggly. Flavor in any fruit is a complicated mix of sugars, organic acids, and many miscellaneous volatile compounds — as many as a hundred in the ripe tomato and more than two hundred in the equally ripe banana.
In the green tomato, most of the sugar is stashed in the storage form of (unsweet) starch. As ripening progresses, the enzyme alpha-amylase — found fulfilling the same function in human saliva — rapidly hydrolyzes this starch, converting it to (sweet) glucose and fructose. Simultaneously, the concentration of (sour) organic acid drops off, and the result, a nice balance of sugar, acid, and volatiles, is what makes up the perfect tomato. Optimal tomato acidity generally ranges around pH 4.0 to 4.5 (pH 7.0 = neutrality), in the same ballpark as red cabbages, onions, and pears. (Lemon juice, in contrast, logs in at a puckering pH of 2.3, and vinegar at 2.5.)
The genetic key to tomato yumminess, according to recent research by Zach Lippman of New York’s Cold Spring Harbor Laboratory and colleagues at Hebrew University in Israel, is a single gene for a chemical called florigen, whose purpose is to tell the growing plant when to stop making leaves and start making flowers. A mutation in one copy of the florigen gene (each tomato plant has two) results in astonishingly higher yields of fruits that are notably sweeter and more scrumptious than those of their nonmutant peers.
Few foods are as delicious as a ripe, fresh-picked garden tomato. Conversely, few are as dreadful as the anemic substitutes found on supermarket shelves in February. Winter tomatoes, which have to be stored and shipped long distances, are picked in the green stage, then exposed to ethylene gas, a process delicately known in the tomato industry as “de-greening.”
Ethylene, primarily a breakdown product of the amino acid methionine, is present normally in fruits and acts much like a hormone, triggering the many activities that lead to natural ripening. It can also lead to unnatural ripening. The ancient Chinese were aware that fruit would ripen more rapidly if placed in a closed chamber with burning incense. In this country, considerably later, orange growers noticed that green oranges placed in rooms with oil heaters rapidly turned into orange oranges. The reason for this color change, at first assumed to be simply heat, was soon discovered to be the presence of ethylene gas, an incomplete oil-combustion product.
Tomatoes are much more resistant to ethylene than are oranges, but will, if determinedly treated, eventually turn reddish. The infamous Walter tomato, developed in Florida where the bulk of U.S. winter tomatoes are grown, was selected for its cooperative uniform response to gassing and its resilience to travel. (It’s a tough tomato; you can play catch with it.) In the chilly off-season, it’s better than nothing — but it’s also proof that, just like trees, only God can make a tomato.
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To Sprawl or Not to Sprawl
In the absence of genetic manipulation, growers agree that the best-tasting tomatoes ripen on the vine — preferably on indeterminate vines. Indeterminate plants are lanky sprawlers that grow steadily throughout the gardening season, grinding to a halt only with the advent of unseasonably cold weather. The larger size and higher leaf count of indeterminate plants mean more sugar production and sweeter fruit. Many heirloom tomato varieties are indeterminate, which may explain their reputation for tastiness.
Determinate tomatoes, in contrast, are bushy, compact, and tidy, usually growing no more than three feet tall. This habit is governed by a specific gene designated sp (self-pruning) which appeared out of the blue as a spontaneous mutation in Florida in 1914.
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Transgenic Tomatoes
The first genetically engineered crop ever sold in American markets was a tomato. Called the Flavr Savr, the tomato was created by the California company Calgene and introduced in 1994 as an improved alternative to the standard cardboardlike, picked-green-and-gassed product ordinarily available to consumers in winter.
The new tomato had a gene, inserted via bacterial carrier, that blocked the production of polygalacturonase, an enzyme essential for softening of the fruit during ripening. In the absence of this enzyme, the Flavr Savr could be allowed to ripen naturally on the vine — thus developing a normal tomato’s battery of flavor molecules — but would still be tough enough for shipping. Though deemed both safe and nutritious by the FDA, the Flavr Savr didn’t make the cut with consumers, and transgenic tomatoes — in a flood of hype about mutants, monsters, and Frankenstein — vanished.
Today, rather than genetic engineering, tomato experts favor “smart breeding,” a technique that combines genetic analyses of plants for desirable traits with traditional crossbreeding.
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Fruit is not an end in itself, but a tomato plant’s clever way of making more tomato plants — a fancy mechanism for seed dispersal. Within each tomato are 250 to 300 tiny seeds, which weigh in at about 5,000 to the ounce. These seeds develop most rapidly during the second half of the tomato maturation period, the one- to two-week pause between the attainment of full growth and the onset of ripening. During this time, the seed embryo reaches full size and the seed coat develops and hardens.
Animal-assisted seed dispersal, of the sort aspired to by the tomato, is known as endozoochory, “seeds inside animals,” or what one researcher terms the “Jonah syndrome.” Here, the seeds are covered by an appealing coat of fleshy food and, at some point during the eating process, are spat out, spilled, or voided (a.k.a. dispersed) by a hungry and helpful animal. For this dispersal to be effective the seeds must escape wholesale digestion or destruction by overenthusiastic eaters, a problem the tomato gets around by producing immense numbers of small seeds. Some inevitably spill during feeding and go on to reproduce the species, and those that are actually swallowed possess coats tough enough to resist the fatal activity of the digestive tract enzymes. By the seed dispersal stage, that’s it for the tomato — until, of course, gardening time next year.
The correct tomato pronunciation, linguists believe, is to-mah-to, from the sixteenth-century Spanish tomate. The word picked up its o in eighteenth-century England, where the insular English believed that all Spanish words ended that way, but retained its short a.
Around here, though, we eat to-may-toes. After all these years of phonetic error, it’s just too blasted late to call the whole thing off.
CHAPTER TWENTY
In Which
TURNIPS
MAKE
A VISCOUNT
FAMOUS
plus
Castles, Lighthouses, and Locomotives,
A Roman Wrinkle Cure,
A Curmudgeonly Cryptographer,
A Diet for Diamond Hunters, and
A Weekly Dish of Woolton Pie
Tulip or turnip,
Rosebud or rhubarb,
Filet or plain beef stew,
Tell me, tell me, tell me, Dream Face,
What am I to you?
DUKE ELLINGTON
The turnip’s finest hour occurred at dinnertime in the sixteenth century when, carved in the shape of a castle (“gilded with egg yolk”), cathedral, or sailing ship, it served as a fantastic centerpiece on the grandest of aristocrat
ic tables. Since then it’s been a steady slide from glory. The turnip, historically, is the favored food of cows, pigs, and desperate peasants. Fewer and fewer gardeners these days bother to grow them, and younger diners, presented with them, have a tendency to push them fretfully about on their plates and hide them under the mashed potatoes.
Still, people have been growing turnips since the Neolithic era, and turnip seeds, saved in pots, have been found in Swiss lake dwellings. Plant scientists hypothesize dual centers of origin for the now-neglected turnip, one in the eastern Mediterranean, the other in Afghanistan and Pakistan. Oldest of the cultivated turnips is thought to be the Asian Brassica rapa ssp. oleifera, commonly known as rape, grown for its oil-bearing seeds. Rapeseed oil, used in lamps since ancient times, was the oil of choice in the nineteenth century for illuminating lighthouses and lubricating steam locomotives. It’s still around today: tastefully renamed canola oil, it’s commonly used in cooking.
The first turnip cultivated in Europe, however, was Brassica rapa ssp. rapa — the garden turnip — grown for its edible roots. The Romans ate them, but — even though the first-century cookbook Apicius includes upper-class recipes for duck with turnips, turnip pickle with myrtle berries, and boiled turnips seasoned with cumin, honey, and vinegar — the Roman turnip was ordinarily considered poverty food. It was similarly a cottage, rather than a castle, vegetable during the Middle Ages; in England, turnips appeared on the occasional family coat-of-arms to indicate a benefactor of the poor.
Medicinally, the turnip, mashed and mixed with suet, was recommended for winter maladies: frozen feet, chilblains, and aching joints. It was also used to treat “goute,” smallpox, and measles, and to make a nice “sope” for “beautifying the face,” a custom that may have been handed down from Roman times, when Apicius urged the wrinkle-conscious to use facial masks of cooked turnip, cream, and mashed rosebuds. Two applications, he claimed, would leave the aging face as smooth as a baby’s thigh. Less frivolously, professional sixteenth-century cutlers used turnip juice to temper steel, and individuals with nothing better to drink fermented turnips and turned them into alcohol.
John Gerard (1597) describes “Turneps” of several types — large and small, round, “peare-fashion,” and “longish;” as does John Parkinson (1629), who mentions white, yellow, and red turnips, and the “Navew gentle,” which is shaped like a carrot. The white kind, a globular turnip with a “pigges tale-like roote” underneath it, is the most common, Parkinson tells us; and both he and Gerard agree that turnips are primarily eaten by the “poore.” In Wales, according to Gerard, the utterly broke didn’t even bother to boil their turnips, but simply gnawed upon them, raw.
Because of the turnip’s generally lousy press, “turnip eater” traditionally meant lower-class dullard. “Let the lowborn dig turnips!” was a German catchphrase dating to the fourteenth century; and in Old French, anything conspicuously worthless was deemed “not worth a turnip.” François Rabelais, in his bawdy sixteenth-century satire Gargantua and Pantagruel, referred to country bumpkins as turnip-chewers, and German scholar Johannes Trithemius, who wrote the world’s first printed book on ciphers and cryptology, began with an introductory poke at the dim-witted common man:
“This I did that to men of learning and men deeply engaged in the study of magic, it might, by the Grace of God, be in some degree intelligible, while on the other hand, to the thick-skinned turnip-eaters it might for all time remain a hidden secret, and be to their dull intellects a sealed book forever.”
In the popular BBC series Blackadder, which traces the fortunes of the hapless Blackadder family dynasty from 1485 to World War I, doofy dogsbody Baldrick (Tony Robinson), servant to Edmund Blackadder (Rowan Atkinson), is noted for his multigenerational lowbrow love of turnips. The Elizabethan Baldrick was famed for his recipe for Turnip Surprise, which — the surprise — contains absolutely nothing but a turnip.
With its vulgar associations and silly appearance — bulbous below, shaggy above — the turnip is an unlikely literary hero, but apparently it has been one since at least the fourteenth century. The Grimm Brothers’ tale “The Turnip,” for example, harks back to a trio of medieval Latin poems, the gist of which is deserved comeuppance. A poor but honest farmer brings an enormous turnip as a gift to the king, and receives a purse of gold as a reward. The farmer’s wealthy neighbor (or, occasionally, half-brother) then decides to give the king a horse, hoping for an even bigger and better reward. Instead, he gets the turnip.
Turnip tall tales date to sixteenth-century Germany, where folk stories variously feature a turnip so big that it filled an entire cart, a turnip that took three days to ride around on horseback, and a turnip so huge that a cow could eat its way into the middle of it and vanish, with nothing left showing but the tip of a tail. Still around today are picture-book versions of the Russian story of the gigantic turnip, a cumulative tale in which an old man and woman plant a turnip and then find that it’s so huge that they can’t pull it up. The result is a tug-of-war with every person and animal on the farm hauling on the turnip, until finally a vegetable the size of a small house explodes out of the ground.
The turnip tales, argues Harvard classics professor Jan Ziolkowski in Fairy Tales Before Fairy Tales (2009), may reflect the human fascination with novelty — we like oddly enormous vegetables — or they may simply give the prolific turnip its due. The turnip is famous for bulk, and for what it has historically provided best: lots and lots of good cheap food.
Introduced to England by the invading Romans along with apples, lavender, and peas, the turnip led a career of relative obscurity until it came to the attention of Charles, second Viscount Townshend. Townshend — later nicknamed “Turnip” Townshend — was a passionate agriculturist who, in the early 1700s, promoted the turnip both as livestock feed and as part of a four-crop cycle of crop rotation with sequential plantings of wheat, barley, turnips, and clover. Daniel Defoe, tramping through Townshend’s home county of Norfolk in 1724, wrote: “this part of England is remarkable for being the first where the feeding and fattening of sheep and other cattle with turnips was first practiced . . . a very great part of the improvement of their lands to this day.”
King George II was so impressed with the Norfolk turnips that he had an instructional report written about them for the edification of his subjects across the Channel in Hanover. Even the irascible William Cobbett admired the Norfolk turnip fields. Jane Austen’s Mr. Knightley, the love interest in Emma (1815), grew turnips.
Turnips were first planted in America by Jacques Cartier, who tended a kitchen garden in Quebec in 1541 while fielding expeditions to collect what he fondly believed to be gold and diamonds. (They turned out to be iron pyrites and quartz crystals, which inspired the contemporaneous French expression “fake as Canadian diamonds.”) The Jamestown colonists planted turnips in Virginia. “Our English seeds thrive very well heere,” wrote Alexander Whitacker in Good Newes of Virginia (1612), a bolstering report to the colonists’ backers in London, citing the pleasant climate, the abundant wildlife, and the success of “Pease, Onions, Turnips, Cabbages.”
Turnips also grew in the gardens of Massachusetts Bay: a letter from Governor John Winthrop to his wife in Boston sends kisses, inquires after the children, and reminds her to get in the turnips. John Randolph, in his Treatise on Gardening (1793), lists “the white and purple rooted Turnep” as best for the table.
At Monticello, Thomas Jefferson, who ate turnips with sugar in ragouts, grew ten kinds.
By the nineteenth century, seed catalogs offered dozens of different turnip varieties. D. M. Ferry, in 1881, listed twenty-one turnips, and Burpee, in 1888, carried sixteen, including the White Egg; the Cowhorn, a white carrot-shaped variety; and the Golden Ball or Orange Jelly, noted for “rich, sweet, pulpy flesh.” Vilmorin-Andrieux’s The Vegetable Garden (1885) describes forty-five, among them carrot-shaped, round, and flat turnips, which last in illustrations look somewhat like hockey pucks.
The notable su
ccess of the turnip paved the way for the rutabaga, which is neither turnip nor cabbage but somewhere in between. While the cabbage has eighteen chromosomes and the turnip twenty, the rutabaga — which cheerfully incorporates both — has thirty-eight. Scientists guess that the crucial combinatorial mating took place at some point in the Middle Ages, possibly in Scandinavia, where the cool climate particularly suits them.
The first written mention of the rutabaga occurs in 1620, usually attributed to Swiss botanist Gaspard (or Caspar) Bauhin, who saw some growing in Sweden. This makes sense, since the common name comes from the Swedish rotabagge, “root bag.” It’s also variously known as the swede, the yellow turnip, or the turnip-rooted cabbage, though officially it has a species name all its own: Brassica napobrassica.
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Rootabaga Country
Carl Sandburg’s Rootabaga Stories (1922) is collection of American fairy tales, first told to Sandburg’s three daughters and set in the fabulous Rootabaga Country, which is named after a turnip.
* * *
The swollen edible bottoms of both turnip and rutabaga are part stem, part taproot. The lower two-thirds, all root, lurks underground, while the upper third, derived from the stem base, remains above. The aboveground portion, exposed to sunlight, accumulates an assortment of purple and red anthocyanin compounds and becomes pigmented, while the shielded root remains pale: hence the familiar turnip’s purple top. The term turnip-pate, common in the seventeenth century, took into account only the snowy nether region, and was applied to individuals with very fair hair, those today called towheads or platinum blondes.
