You know the great scent that fills the air when you start to peel a fresh-picked orange—or almost any fresh fruit? That smell is more than appetizing; it represents the plant's volatile oils. Volatile oils are the delicate compounds within a plant—fruit or vegetable—that give it its distinctive smell and taste. They are volatile because they are easily destroyed by exposure to the air or to heat. They are desirable because they are crucial to the freshness—and healthiness—of food.
Processing produce kills volatile oils—through heat, through long exposure to air, and through the addition of chemicals and preservatives that artificially extend the life of the food (but not of the oils). By their nature, processed foods cannot contain volatile oils. They will smell less appetizing than the fresh version, and not taste as good either. By contrast, the very presence of intense smell and taste in fresh foods signals the hidden virtues of the oils, which are often argued to have anti-bacterial properties and to contribute to cellular repair.
Clearly, you want to hang on to as many of these molecules as possible, all the way from harvest to plate. How to go about this without eating a raw diet? Here are a few tips for prep, cooking, and storage:
Start by eating fresh fruits and vegetables while they're still fresh, and without processing. Buy and use fresh raw certified organic produce and products whenever possible; they're well worth the expense and are environmentally responsible.
Always clean fruits and vegetable with a produce wash, then rinse well. After that, keep the slicing and dicing to a minimum. Food cut into small pieces means more surface is exposed to the air and more nutrients are lost. Bigger pieces cook slower, but more of the essence and flavors are retained.
The best cooking method is steaming, in a stainless steel basket over water with the pan covered. This method is quick, and fewer nutrients are emitted via steam or dispensed in cooking water.
If you can't steam, try to go with low and slow cooking. Lower heat and longer cooking time retains nutrients and flavor across the board. Learn how to use the lower power settings on your microwave; what's another two minutes, really? After steaming, the cooking methods for vegetables, in order of preference, are: baking, then broiling, grilling, and microwaving, using boil-in or bake-in-bags.
You could probably guess that deep frying is a bad idea—but you might not expect that one of the worst ways to cook vegetables is to boil them in water. This completely leeches the oils out of the produce, leaving it totally depleted. You toss your volatile oils down the sink, instead of down your throat.
Of course, sometimes you can't get around cooking produce in water. In that case, use a trick to get the volatile oils back into your diet. Freeze the water used to boil fruit for a sauce or pie in an ice cube tray. The flavorful and nutritious 'runoff' makes for smart ice cubes for drinks. Stored veggie cooking water (or veggie water ice cubes) make great soup stock for your next slow cooker extravaganza.
About Stephen Perkins: Steve Perkins, CDN of Los Angeles is the author of "The Muscle Kitchen: Practical Bodybuilding and HIV Nutrition." He presents unique graphic keynote seminars entitled "User-Friendly HIV+ Nutrition" and "Nutrition for Bodybuilding" and "Cook as if Your Life Depends on It, Because it Does." Perkins also developed "Ready-Aim-Fuel," a series of food target magnets. Check it all out at TheMuscleKitchen.com.