Lore • Classification • Nutrition • Production • Preparation
Popular wisdom claims that anything good is bound to be either sinful, or fattening…alas, most gourmet delights fall into the second category - but asparagus is one of the few exceptions.
Lore
Asparagus has been in cultivation for more than 2500 years, was believed to originate in either Greece or Turkey, was considered a food for the gods by the Egyptians, and the Greeks are credited with introducing the delicacy to the Romans. The Greeks/Romans valued asparagus for medicinal uses – treating bee stings, heart ailments, dropsy and toothaches. Both the Arabs and Romans believed asparagus had aphrodisiac properties. In an early historical reference, Apicius, a famed Roman epicure of the first century, extolled the erotic powers of asparagus, prepared as follows: “fry asparagus in lard, add egg yolk/hot pepper”. One wonders if the recipe bears any relation to the Spanish saying, “go fry asparagus”, which usually means a totally useless activity.
Asparagus always has been considered a luxury vegetable. It was highly prized in ancient Egypt, Greece, and Rome as a delicacy, occasionally a food fit for the gods, and (as some even attributed to it), an aphrodisiac. Its use waned in Europe for several centuries until the reign of Louis IV, who encouraged its production because of his personal fondness for asparagus spears. The cultivation of white asparagus was developed in the 19th century, when growing vegetables white - what gardeners call blanching - was in vogue. It became so popular that green asparagus, which is much easier to grow and harvest, nearly disappeared from French tables. Just in the last five years has it become common again. Asparagus suffered during the Middle Ages, was rediscovered by the French - but again fell out of favor in Victorian days/20th Century, thanks to Sigmund Freud.
White asparagus remains a very expensive vegetable because production, harvesting, and processing do not lend themselves well to mechanization. Very selective cutting must take place constantly just as the spears emerge, throughout the asparagus season, which starts in April and continues through June. The extreme tenderness of the spears preclude much automated handling. Commercially grown asparagus has been bred selectively from wild plants that are native to Asia, and Europe. However, green asparagus, once considered the Cadillac of green vegetables (largely due to its price) and the quintessential culinary harbinger of spring, now thanks to cultivation in places such as Peru, it’s more reasonably priced and available almost year-round.
Classification
The asparagus plant belongs to the Liliaceous family (Lilaceae) which consists of some 150 varieties. It is a member of the lily family, which includes chives, garlic, onions, shallots and yams, with flowering lilies of hundreds of kinds as aloe, daffodils, hyacinths, tulips and yucca. Most of them are characterized by underground bulbs or tubers. Only Asparagus officinalis is cultivated for consumption. It is a hardy plant in temperate climates, usually not harvested for the first 3 years, after the crowns are planted, allowing the crown to develop a strong, fibrous root system. A well-cared for asparagus planting will generally produce for about 15 years without being replanted. It thrives best in loose, deep sandy soil that is well-drained, and can by grown on both irrigated and unirrigated land. It can be found growing wild along the roadsides of Navarre.
The asparagus plant has large fleshy roots, and an underground stem system shaped like a claw which is termed Rhizome. Small buds appear on the Rhizome, and in the spring, these buds shoot up as sprouts, which become the edible part of the plant. Temperatures during this period (April to June) should be between 12º and 20º C with a minimum temperature no lower than -1º C. If the shoots are allowed to flower, they develop into a plant with fern-like foliage that grows to about 0.5 to 1.5 meters (18 to 54 inches). Asparagus will grow 7-10” in a day when temperatures reach 90º. The length of harvest is generally 70-80 days. After harvest, the spears grow into ferns, which produce red berries, and the food/nutrition necessary for a healthy and productive crop the next season. Although propagation by seed is possible, most propagation is in the form of divided subterranean root stocks that are called "crowns."
Nutrition
Galen, a second century Greek physician/philosopher, who was the supreme authority on medicine for centuries, claimed asparagus had edifying medicinal properties, some of which modern medicine has corroborated. Pliny the Elder, of first century Rome, had already termed asparagus “prodigia ventras”, loosely translated as good for digestion. Hollywood vamp Zsa Zsa Gabor confessed to being an insatiable asparagus buff, and claimed that “power, wealth and asparagus were the most powerful aphrodisiacs”.
While we will leave claims of aphrodisiac powers for the reader to decide for herself/himself, recent scientific studies in the U.S. support evidence that asparagus may help prevent certain types of cancer. Doctors now emphasize the need for diets rich in fiber, and asparagus is an ideal source that helps regulate intestinal function. Asparagus, known today as a highly nutritious and flavorful vegetable, is a nutrition-dense food which is high in folic acid, packed with vitamins A, B6, and C, and minerals such as calcium and phosphorous. Asparagus has carotene, iron, potassium, and zinc. Asparagus also has diuretic properties, making it beneficial for kidney functions, and a valuable aid to dieters. Recent studies have found that an asparagus extract also has a beneficial action on the heart muscle - and a slight sedative /relaxing effect, making it an ideal food to calm tense nerves. Rich in copper, essential amino acids and phosphorous, asparagus is not only delicious but healthy and nutritious. Modern technology also reveals asparagus as a leading source of glutathione, a potent antioxidant, and a cancer fighting agent. It is rich in rutin, which strengthens blood vessels. It is high in folacin, which could prevent the neurological birth defects of spina bifida and anencephaly. Weight watchers, rejoice! There are few gourmet delights that are not fattening - and asparagus is one of them. With only 20 calories per 100 grams, and containing practically no fat/sugar, asparagus is an unlimited filling vegetable, which contains no cholesterol, and is low in sodium.
Production
Cultivation of asparagus was introduced in the northern region of Navarre in the early days of Spain’s Arab occupation, which began in the 8th century. Widespread production began about 50 to 60 years ago. Navarre is expected to produce approximately 24,000 tons of asparagus, roughly one third of Spain’s production…followed by Andalusia, and Extremadura. In Navarre, over 95% of processed asparagus is white, and exports account for half of the production. In Navarre, asparagus connoisseurs claim the best asparagus is the first of the season. A popular saying insists:
“April’s harvest for me, May’s harvest for the landowner, and June’s harvest for no one.”
The Alsace, the heart of the Rhine in France, is also an important asparagus growing region. White asparagus was once grown for canning in California but died out when the market fell to international competition. Now it is only imported to the United States, but demand is growing. We import both our green and white asparagus from both China and Peru.
Asparagus has been harvested in the U.S. since the 1870’s. California produces approximately 70-80% of the domestic fresh crop in the U.S., with Michigan/Washington following. Michigan/Washington direct their production to processors, both canners/freezers.
According to the Peruvian Asparagus Importer’s Assosication, exports to the United Sattes are forecasted to increase by 8-10% for the 2008-09 season. In 2007, the United States imported more than 273 million pounds of asparagus, of which Peruvian asparagus represented over 56% of the total world supply. The U.S. Department of Agriculture further indicated an approximately 2.2 million-pound increase from 2006 to 2007 of Peruvian asparagus imports. Also increasing is the import dollar value. In 2007, Peruvian asparagus represented 57% of the total U.S. import dollar value, according the USDA figures.
Asparagus ranks among the top-20 best sellers for fresh vegetables consumed in the United Stetes. As consumers are increasingly lookin for healthy and conveninent foods, the asparagus industry is proving consumers with options that provide convenience, savings, ready-to-east selections, and are microsaveable. By these criteria, fresh asparagus is an easy-to-prepare and convenient option for U.S. households. Additionally, consumers are 32% more likely to purchase asparagus, deeming it a highly nutritious option. The Produce Marketing Associateion’s December 2007 data indicate that U.S. fresh asparagus consumption has been trending upward since 1998 on a per capita basis.
In the asparagus fields, the soil, covered with plastic, to trap the sun’s heat, is warm to the touch - cooled only by the troughs between mounds of earth. The harvesters are like cats on a mouse hunt, creeping along, heads down, with their gouges, or stick-like asparagus tools, pawing at the narrow mounds. Their eyes scour the ground for a white nub protruding from the lumpy soil. When an asparagus is spotted, the kill is swift. The harvester plunges the gouge into the base of the mound, and with a quick jerk, and a snap, cuts off the spear and lifts it from deep within the soil, like an archeologist recovering an ancient tusk. There is no way to harvest white asparagus other than by hand. The harvester then scoops dirt back into the hole - for the same plant will produce another dozen stalks - and moves on down the row. Spring sun shining on the plastic-covered mounds makes the fields appear like a rolling sea. As the asparagus stalks poke their heads through the soil, they’re covered with dirt to prevent the chemical interaction with the sun known as photosynthesis which creates the chlorophyll that turns the plant green. Still, the shoots stretch for warmth - and are buried anew until the day of harvest.
After picking, each spear is graded by size and color. Unlike the situation with many spring vegetables, which are prized for their thinness, with white asparagus, bigger is better. And whiter is better, too. White asparagus is simply the same variety grown without light. A green or purple tip means the asparagus was harvested after its tip grew above the soil. Purple asparagus is usually larger and sweeter than the green veriety. It has a creamy green interior and tends to lose its royal color when cooked.
Early in the season, the dusty catch is small. Spears do not begin sprouting until soil temperature nears 15ºC/59ºF. It takes a sharp eye to spot the slight crack in the soil’s surface, indicating a stalk pushing its way up through the mounded soil. What is missed today, will see tomorrow a stalk poke through to the light, its white tip turned to violet, decreasing its market value by half. Trucks ply the field, collecting the workers’ asparagus, then delivering it to a central processing plant. Once delivered to the cannery, the asparagus begins processing immediately - or can be stored for a few hours in large refrigerated rooms.
Processing begins with washing and peeling, that is generally done by hand, or more recently by special peeling machines. Asparagus spears are held vertically, rinsed continually, and rotated twice, where special blades make twelve peels per sprout. Next, the peeled asparagus is again washed, scaled, and selected by hand. Perfect asparagus stalks are cut from 7-8 inches. Pickers classify the asparagus by caliber, color, and condition. Whole stalks are called spears or stalks, when their length is 3-3/4" or more. From 2-3/4" to 3-3/4" in length the canned product is called tips. If less than 2-3/4" long, the product is identified as points. Cut into segments, canned asparagus is known as cut spears or cut stalks. Highest prices go for extra thick, totally white asparagus - most of which is consumed in restaurants.
Classifications include:
Extra thick: .76”+ in diameter Thick: .44” - .75” in diameter
Standard: .36” - .43” in diameter Thin: .35” or less in diameter
A machine can distinguish caliber/size, but is color-blind.
The asparagus may be scaled again, cooled in dry vapor, drained, weighed individually, and bottled/canned before sterilization- or frozen for export. Pressure, temperature, and time are controlled by computer. Laboratory controls are done by canneries, but checked by industry officials too. Quality controls include acidity, caliber(thickness), clarity of water, color, defects, and fibrosity. Macrobiology assures pure sterilization.
When choosing your own fresh asparagus, look for odor-free, bright green spears with tightly closed tips, uniform in size to ensure even cooking. Thicker spears are just as tender as thinner ones; tenderness relates to color – the greener the better. The spears that are firm are the freshest. Break one of the stalks. It should snap cleanly. Use asparagus immediately since the natural spears begin to wane, and convert to tough indigestible fibers as soon as it is picked. If you have to store it for a day or two, wrap the ends in damp paper towels, put the spears in a paper bag, and set them in the refrigerator’s crisper.
Consumers ask us about the flecks/specks on some asparagus. The specks are called ruten or rutin, which is an edible, safe protein that grows naturally on asparagus. The color can be silver to yellow-green. There are no natural ways to prevent it. It is caused by a natural protein drawn out of the asparagus by the vinegar. It is harmless. Rutin is a natural aphrodisiac (check the internet and you can find several websites devoted to the subject).
To store asparagus, trim the tough end of the spear. Store in the refrigerator with the spears covered, standing upright in about 1 inch of water, or wrap the ends in a wet paper towel, and cover with plastic wrap. Stored properly, asparagus will keep a few days. Before cooking, trim the tough ends, or hold the stalk by the ends and bend; it will snap at the point where it becomes tough. If you like, peel off the tough outer skin.
Preparation
Gourmands claim fresh white asparagus is best served slightly warm, after it has been allowed to cool a little from cooking…and can be used as an hors d’oeuvre, entree, or as a main course. To cook asparagus, first break the woody end where it snaps easily. Rinse the tips. Drop the asparagus into simmering water, cover for 10-15 minutes (thickness/crispness are your choice). Keep it simple - to enjoy the subtle flavors…a little olive oil should suffice. Asparagus can be used in everything from hors d’oeuvres, to entrees, to main courses - and to dress up the most ordinary salads. True gourmets insist that au natural is the best - but asparagus au gratin is another favorite, or chopped in omelets, or in a cream soup. We have plenty of recipes. What green asparagus is to North Americans, white asparagus is to Europeans/South Americans - the most prized of all seasonal delicacies. In addition to green/white asparagus, there is violet asparagus, which is tinged a purplish color, but turns green when cooked. It tends to be sweeter/less fibrous than either of its counterparts.
Asparagus requires just minutes to cook. To avoid overcooking, remove it from the heat, while it’s still underdone; it will cook a bit more as it cools. Here are a few basic cooking methods adapted from the California Asparagus Commission:
- Grill: Brush or toss spears with oil. Grill over medium heat 4-6 minutes until browned and crisp-tender;
- Microwave: Place 1 pound of spears in a microwave-safe dish with ¼ cup water. Cover with plastic wrap but vent one corner. Microwave on high 3-6 minutes; let stand 3 minutes before serving;
- Blanch or Boil: Bring 1 to 1 ½ inches of water to a boil in a large skillet. Salt the water slightly to help retain the asparagus’s color. Add the asparagus, bring to a boil, then reduce the heat to a simmer and cook 2-5 minutes until tender;
- Steam: Place spears on a steamer rack in a large saucepan of boiling water. Cover and steam about 5 minutes.
Fat or Skinny asparagus?
Each type is good. Some think fat spears have more substance, and more crunch equals more taste. It is impossible to say either is better. Both are good. Does it matter what type you use? The answer is yes, and aside from appearance. With either, you must first break off the woody bottoms (magically, they snap off in pretty much the right place every time), a quick but necessary chore. But it is always worth peeling thick asparagus, from stem to the bottom of the flower bud. The best way to do this, is with a vegetable peeler. Lay each spear on a flat surface, and give it a few quick strokes.
The difference between peeled and unpeeled thick spears is substantial. When they are peeled, they can be cooked for considerably less time, leaving them bright green, and perfect crisp-tender, rather than a soggy mess. They are done when you can easily insert a skewer or a thin-bladed knife into the thickest part of the stalk. (If you don’t peel them, the soggy mess is just about the only way to get the skin tender.) They are also far more attaractive when peeled and not overcooked; the color of the stems just pops out at you. After peeling, they are in great shape for grilling, quick-steaming, or poaching. And once that’s done, they are also terrific cold, served with a simple vinaigrette, or dipped in mayonnaise, and they make a wonderful base for salads.
I don’t find skinny asparagus spears quite as satisfying for the uses above; they tend to overcook when steamed or poached, and they are never as good-looking. Also, for every fat spear you would need two or four skinny ones, making peeling a nuisance. Fortunately, the thin ones are thin-cooked so quickly, that you can stir-fry them without parboiling, and this makes them practically a convenience food: snap off the bottoms, cut up and cook. You can roast them in less than 20 minutes with a bit of olive oil. Top with bread crumbs or grated Parmesan (or another hard or semihard cheese), or both, to make a quick gratin. Because they have less fibrous material, thin asparagus are ideal for making a quick pureed soup, like vichyssoise. You can also use them to make a guacamole-like dip; cook until tender, puree and substitute for avocado.
So there is a difference between thick and thin, and it is more than cosmetic. But that doesn’t mean either is better.
Asparagus can be used in everything from hors d’oeuvres, to entrees, to main courses - and to dress up the most ordinary salads. True gourmets insist that au natural is the best - but asparagus au gratin is another favorite, or chopped in omelets or in a cream soup. Often, however, simplicity reigns. Due to the lack of chlorophyll, the flavor of white asparagus is milder than green. White asparagus - pale, elegant, and eerily unnatural, familiar, yet as unexpected as an albino squirrel.
At Le Cirque 2000 in New York, a plate of green/white asparagus spears – served cold in vinaigrette, or hot, dressed with hollandaise – can be had for $35.00 as a first course. Delicious. Unique. Enjoy!