27 April, 2016

Asparagus

native to: coastal regions of the eastern Mediterranean and Asia Minor; first cultivated in ancient Greece
in season here: April-June

Foodies will tell you to avoid asparagus thinner than your pinkie, which they describe as "grassy," because it has less flavor and is so easy to overcook. Contrary to reputation, very thin asparagus is not more tender than finger-sized stalks, as long as you break the bottoms off the stalks where they snap naturally rather than cutting them. Some argue that thick asparagus is more wasteful, to which I reply (perhaps a bit snootily) that the tough ends can be peeled, used for soup, or maybe added to smoothies, and if you're that concerned about cost perhaps you should have some nice cabbage instead. The thickness of the shoots reflects the vitality of the root; thin shoots come from roots that either are too young and should be left another year before starting to harvest or have already been harvested enough and should be left to develop their wonderful lacy fronds and regain their strength. While straight stalks are generally preferred, there's nothing wrong with a bit of curl in the tips if you're serving your asparagus cut rather than in whole spears. The curve is caused by windy conditions before harvest and makes no difference in the taste.

Asparagus is best eaten fresh, although it can be OK frozen if reheated carefully. Canned asparagus is generally not suitable for human consumption (yes, I'm being snooty again. I consider asparagus to be something of a luxury item that should be done right or not at all). Asparagus will continue to grow after picking; most vegetables do, but asparagus is particularly vigorous. Most sources recommend some variation of storing asparagus with the cut ends wrapped in a damp paper towel, but I've had better success storing them in about an inch of water, either carefully propped up in a good plastic bag or placed in a deep, flat-bottomed container with a plastic bag tucked over them.

Asparagus is a member of the lily family; there are some 300 varieties, but only about 20 are edible. Under ideal conditions, it can grow 10 inches in 24 hours. The roots should be three years old before their first harvest, but then will produce for about 15 years before needing to be replaced. White asparagus, also called blanched asparagus, is grown in trenches, with the dirt gradually filled in to keep the shoots covered so they don't develop chlorophyll; it is more expensive because of the extra labor involved. There is also purple asparagus, which is smaller and has a sweeter, "fruitier" flavor. The purple color comes from phytonutrients called anthocyanins.

Asparagus contains saponins, which have anti-inflammatory and anti-cancer properties and have been linked to improvements in blood pressure, blood sugar regulation, and blood fat levels. It also contains inulin, a prebiotic that supports good bacteria and therefore improves digestion. It's full of antioxidants, including vitamins C and E, beta-carotene, zinc, manganese, selenium, and glutathione. Other nutrients in asparagus include vitamins B1, B2, B6, and K, folic acid, niacin, choline, copper, pantothenic acid, and most of the other "usual suspects." It is a diuretic, making it a good choice for people with edema or high blood pressure, and a useful addition to a purifying or detox regimen.

Wild asparagus has long been used medicinally in Asia, particularly in India. Asparagus was first cultivated in ancient Greece, where it was used to cure toothache and prevent bee stings. It is also traditionally considered an aphrodisiac, probably because of its shape. In colonial times (and perhaps earlier) asparagus was sometimes called "sparrow grass," leading to the traditional nickname "grass" that is still used in some circles today.

Perhaps the most curious aspect of asparagus is the odor it causes in some people's urine. There appears to be some genetic basis in both the metabolism of asparagus in a way that produces the odor and the ability to smell it when present (and the two traits seem to appear independantly of each other). There is little agreement as to what substance(s) in the asparagus cause the odor, and in fact the studies have produced very different results. The odor has not been linked to any health issue, however; the only health concern with asparagus is the presence of purines, which can break down into uric acid and cause trouble for people with gout or a tendency to kidney stones.

Read more:
label-style nutrition information for raw asparagus
label-style nutrition information for cooked asparagus
Nutrition and You
MNT Knowledge Center
USDA asparagus links

*After I wrote this, I got to wondering about it and decided to test it for myself. My informal experiment showed almost exactly the same 50% loss from snapping a pound each of thin and thick stalks -- in fact, the thick stalks actually lost a statistically insignificant fraction of an ounce less. So choose the thickness you prefer and among us we'll eat it all!

Versión en español: this post is also available in Spanish.
Esperanta traduko: this post is also available in Esperanto, because Dana is a language geek.

20 April, 2016

Spring stir-fry (second version)

a drizzle of sesame oil (about 2 tsp., depending on pan size)
up to a pound of pork sliced for stir-fry
thinly chopped onions to taste, optional
1-2 Tbsp. ginger-flavored soy sauce (or regular soy sauce and ginger to taste)
1-2 Tbsp. oyster sauce
1 bundle asparagus, ends snapped off (about a pound before snapping), broken into 1 to 1-1/2 inch pieces
1 winter pear (such as Bosc), cored and sliced into about 1/4-inch thick pieces; peeling is optional
1 tsp. rice wine vinegar, or to taste, optional

Add enough sesame oil to a medium frying pan or wok to coat the bottom. Add pork, onions, and soy sauce, and cook until the pork is only slightly pink, stirring frequently. Add oyster sauce and stir in, then add asparagus. When asparagus has started to cook (or at once if it's fairly thin), add pear drizzling with vinegar before stirring in. Cook until all ingredients are done, being careful not to overcook the asparagus (asparagus should be "al dente" and not yet limp or slimy); the pear can be a little undercooked if necessary. If the asparagus is fairly thick, make sure there is enough liquid in the pan to create some steam, cover, and let cook about 3 minutes. Makes 2-3 servings over rice or noodles, or a hungry person can eat the whole thing unaccompanied if not required to move afterward.

By Dana Huffman.

Versión en español: this post is also available in Spanish.
Esperanta traduko: this post is also available in Esperanto, because Dana is a language geek.

06 April, 2016

Hazelnuts

native to: the most commonly found commercial variety is native to southern Europe and Turkey, although there is a wild hazelnut that is native to the Pacific Northwest
in season here: fall

Hazelnuts, filberts, and cobnuts are members of the birch or Betulaceae family. Cobnuts are a rounder species, while filberts are more elongated. The name "filbert" may come from the nuts' tendency to mature around the feast day of St. Philbert, the 22nd of August; or it may be a corruption of the term "full beard," referring to the nut's husk. Some use the names hazelnut and filbert interchangeably while others consider them different, if very similar, nuts. Hazelnuts are a significant commercial crop in Washington and Oregon (it's Oregon's official State Nut), probably first introduced into Oregon by early French settlers. A century ago, railroad companies advertised the possibility of hazelnut orchards in the Northwest as part of their efforts to get people to move to this area (and have themselves and their supplies shipped in by railroad, of course). The wild hazelnut that is native to the Pacific Northwest is not very suitable for commercial production, being protected by a closer involucre or husk (this wrapping of leaves is particularly prickly in the case of our native nuts), but if you're willing to put in the effort to harvest them, they're perfectly edible. Most of the hazelnuts in stores are of the "Barcelona" variety and are often a year or more old, but if you can find an orchard from which to buy directly you'll get fresher nuts and may find other varieties (Holmquist Orchards offer a variety called DuChilly that makes a good snack). The skin of hazelnuts is somewhat bitter, but can be removed after roasting by rubbing a layer of nuts in a towel (the motion would look similar to rolling out dough).

The wood of the hazel tree is sometimes used in bows, and the straight shoots make good arrow shafts; hazel wood is also a traditional choice for divining rods. The trees are a traditional choice for hedges, especially in England, and can attract butterflies. The hazelnut tree blooms in the middle of the winter and is pollinated by the wind; the nuts begin to form in June.

A Chinese manuscript from 2838 B.C.E. lists hazelnuts among the five sacred nourishments divinely bestowed on humans. In about 200 C.E., the Greek physician Dioscorides wrote of filberts that "It cures chronic coughing if pounded filbert is eaten with honey. Cooked filbert mixed with black pepper cures the cold. If the ointment produced by mashing burnt filbert shells in suet is smeared on the head where hair does not grow due to normal baldness or to some disease, hair will come again."

Like other nuts, hazelnuts are good for the heart. They have high levels of folates, which may help prevent depression, and the highest proanthocyanidin content of any tree nut, making them useful in reducing the risk of blood clots, urinary tract infections, and certain kinds of birth defects. They're high in fiber and a particularly good source of copper and manganese. They're a bit high in fat, but it's almost all good fat such as mono-unsaturated fatty acids. Hazelnuts are also a good source of vitamins A and E, as well as arginine, an amino acid that helps relax blood vessels and lower blood pressure. Hazelnut oil is good for the skin, and a popular carrier oil for traditional medicines.

People who are allergic to peanuts, mugwort pollen, Brazil nuts, birch pollen, and macadamia nuts might also be allergic to hazelnuts.

Read more:
label-style nutrition information for raw hazelnuts
table comparing nuts
oregonhazelnuts.org
Seed Guides
oregonhazelnuts.org
Dorris Ranch Living History Farm

Versión en español: this post is also available in Spanish.
Esperanta traduko: this post is also available in Esperanto, because Dana is a language geek.