Iced tea sounds like a refreshing refuge from a hot August sun, but research indicates that a cup of the hot stuff might better serve to cool us down.
And while they're no substitute for an air conditioner on a muggy day, herbs known as "refrigerants" have more than taste to offer.
Not to be overlooked in the scheme of things is that minuscule part of the brain known as the hypothalamus -- the body's regulator of appetite, sexual rhythms, water balance and emotions, which also tells the body whether it should store or lose heat. Situated at the brain's base, above the bridge of the nose near the oral cavity, the hypothalamus, like a thermostat, can be triggered by the temperature of the food we take in, suggests Sandra Frankmann, a postdoctoral fellow studying thirst and sodium appetite at Philadelphia's Monell Center.
Ice cream, for instance, chills the mouth, which cools the hypothalamus, which in turn relays the message that the body is losing heat. Exactly the opposite occurs when ingesting hot foods. Drinking something hot, then, "might trick the body into reducing its temperature," Frankmann suggests.
Moreover, what we add to our food can make a difference in body temperature. "Heavily spiced foods make us sweat," says Dr. William Dietz, clinical research director at MIT. "Part of the response to such food is a pain response in the tongue and mouth . . . sweating, then, is a sympathetic nervous discharge." And sweating keeps us cool.
Fortunately, there's an alternative way to combat the heat, with a diet more substantial -- and assuredly more appealing and less painful -- than cups of steaming tea and entrees flecked with chilies.
Enter the cool summer herbs.
Rex Talbert, a NASA electrical engineer who's made a hobby of studying the chemistry of herbs, refers to them as "refrigerants, in the old sense." Mints in particular are cool to the taste, says Talbert, because the menthol content in many varieties causes a reflex action in which we suck in air, enhancing the cooling sensation. Anyone who's sucked on a mentholated lozenge knows the feeling.
Mints are both soothing and varied in number: Not only is the herb grown in a wide range of flavors, from grapefruit to a delicate chocolate, but it also varies in intensity, from the relatively mild garden variety to the most penetrating and menthol-saturated Japanese mint.
Cool summer herbs aren't limited to mints, however. There are a host of other herbs, including lemon verbena, borage, salad burnet and pineapple sage, among others, that "carry us past the point of cooling in the physiological sense to cooling in the psychological sense," suggests Talbert. The aromas of these herbs are indeed reminiscent of a number of fruits and vegetables we associate with coolness or refreshment. Lemon verbena has a soothing, citrus appeal, borage a slight melon-like aroma; salad burnet is akin to a cucumber in taste, and pineapple sage evokes a light breeziness.
Holly Shimizu, curator of the herb garden at the National Arboretum, agrees. "I think the herbs actually do refresh us, but it's our association with them" wherein the greatest attraction lies. "We think of pungent seasonings like rosemary and oregano as winter herbs" for use in hearty soups and stews, says Shimizu, "for these are also herbs that dry well." She combats warm weather with lemon verbena-laced tea and suggests placing a sprig of a favorite herb (such as lavender mint) in the car to make driving cooler. Or take example from those in warm weather climes, who "wrap their foods in mint leaves . . . and eat small bowls of fresh herbs with their meals."
Herbs aren't just for garnishes. Here, from area herb aficionados and restaurateurs, are six delicious ways to beat the heat. RESTAURANT NORA'S SPEARMINT RELISH
2 jalapeno peppers, seeded
1/2-inch piece fresh ginger, peeled and sliced
1 small onion, coarsely chopped
3 spearmint leaves, or more to taste
1 tablespoon sugar
1 tablespoon lemon juice
Salt to taste
Place all ingredients in a blender and blend, using just enough water to make a homogeneous paste. HENRY DINARDO'S CRAB-STUFFED ARTICHOKES WITH LEMON VERBENA AND THYME DRESSING (4 servings)
4 medium artichokes, trimmed, and chokes removed
Juice of 1 lemon
1 1/2 tablespoons red wine vinegar
1/2 teaspoon salt
FOR THE LEMON-THYME DRESSING:
1/2 cup fresh lemon verbena
1 tablespoon fresh thyme
1/3 cup white wine vinegar
2 egg yolks
1/2 cup vegetable oil
1/2 cup untoasted sesame oil
1 teaspoon sugar
Salt and freshly ground white pepper
FOR THE STUFFING:
2 cups lump crab meat
1 teaspoon each red, yellow, and green peppers, finely diced
To poach the artichokes: place the artichokes, tips up, in a large saucepan. Add cold water to cover, and then add the lemon juice, red wine vinegar, peppercorns and salt. Heat to boiling; reduce the heat and simmer, covered, until base of artichoke is tender to the touch.
Remove artichokes and drain them upside down in a colander. Chill, covered, two hours in the refrigerator.
To prepare the dressing: In a small saucepan, add lemon verbena and thyme to vinegar; heat to simmer. Remove from heat and allow to cool. Strain vinegar mixture and allow to cool.
In a mixing bowl, beat egg yolks and slowly add cooled, strained vinegar. Slowly add both kinds of oil while whisking, until emulsified. Add sugar. Salt and pepper to taste.
To finish: Mix the crab meat with diced peppers. Stuff artichokes with 1/2 cup crab meat mixture. Spoon dressing over the top and around the artichoke, and garnish with a sprig of lemon verbena. RESTAURANT NORA'S TZATZIKI SAUCE
1/2 large cucumber
3/4 cup plain yogurt
1 garlic clove, minced
3 bunches mint, finely chopped
1 teaspoon olive oil
Salt and pepper to taste
Peel and seed cucumber; grate and lightly salt. After 5 minutes, squeeze juice from cucumber. Mix cucumber with yogurt and add garlic, mint, and olive oil. Season to taste. HENRY DINARDO'S GRILLED SMOKED SALMON WITH MINT-MANGO VINAIGRETTE (4 servings)
4 ripe mangoes, peeled, pared from seed and diced
1/2 cup finely diced red bell pepper
3/4 cup virgin olive oil plus extra for salmon
1/4 cup champagne vinegar
1/4 cup mint (preferably spearmint) leaves, chopped fine
1 teaspoon salt
1/2 teaspoon white pepper (preferably freshly ground)
1/2 teaspoon sugar
4 4-ounce pieces of thinly sliced smoked Norwegian salmon, skinless and boneless
To prepare vinaigrette: Combine and gently toss in bowl the mango and bell pepper. Slowly add, alternating, the olive oil and champagne vinegar. Gently fold in the finely chopped mint. Season to taste with salt, white pepper and sugar.
Refrigerate overnight to allow flavors to blend.
Thinly slice the smoked salmon on the bias and dip in olive oil. Season lightly with freshly ground white pepper. Cook slowly over an outdoor grill, with either charcoal or mesquite wood chips, for 1 minute on each side, turning gently to obtain grill markings and heat through.
Remove marked salmon slices and divide into 4 portions. Arrange on plates and garnish with chilled mint-mango vinaigrette and a fresh sprig of mint, preferably spearmint. HENRY DINARDO'S MINTED LOIN OF PORK (4 servings)
2-pound loin of pork (boneless)
FOR THE MARINADE:
1 clove garlic, minced
1 medium-size onion, minced
1 stalk celery, minced
1 leek, minced
1 tablespoon fresh thyme, crushed
1/2 tablespoon rosemary
2 tablespoons finely chopped Italian parsley
1 tablespoon crushed black peppercorns
1/2 tablespoon sea salt
1 cup olive oil
1 pineapple, peeled, cored and crushed in a blender
1/4 cup orange zest plus the pulp of 1 orange, chopped
1/2 cup fresh mint (preferably pineapple mint) plus extra for garnish
1/3 cup tomato pure'e
1 cup port wine Combine the marinade ingredients and marinate loin of pork overnight.
Slowly grill marinated pork loin over mesquite or charcoal grill for 15 minutes, turning every 5 minutes.
Remove from grill and finish roasting in a 450-degree oven.
Remove from oven and allow to rest for 10 minutes. Slice thinly and garnish with sprigs of pineapple mint. WINDOWS' HONEY ICE CREAM WITH LAVENDER BLOSSOMS (8 servings)
4 cups whipping cream
1/2 cup strong-flavored thyme or heather honey
5 egg yolks
A few lavender blossoms
Mix together 3 cups of the cream, the honey and egg yolks, and cook in a double boiler over very hot water. Stir constantly with a wooden spoon until the mixture thickens to the consistency of a cre me anglaise, about 10 minutes. Add the lavender blossoms about the last minute or two of the cooking time. Strain the mixture and stir in remaining cream. Cover the cream and chill completely, then freeze in an ice cream freezer.
Sources for fresh herbs and herb plants used in the recipes include:
Washington Cathedral Nursery, Wisconsin and Massachusetts avenues NW, (202) 537-6263.
Bittersweet Hill Nurseries, 1274 Governor's Bridge Rd., Davidsonville, Md., (301) 798-0231.