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As seen on BCTV October 22/02

Members of the Cruciferous Family

Broccoli, bok choy, Brussels sprouts, cabbage, cauliflower, greens, kale, kohlrabi, mustard, rutabaga and turnip are all amazing vegetables with over 30 phytochemicals, broccoli being one of the best. The first cancer protective phytochemical identified in cruciferous vegetables back in the 1970’s was indol-3-carbinol. More recently, sulforaphane (an isothiocyanate) and dithiolthiones, concentrated in broccoli, have been found to trigger the formation of glutathione-S-transferase (GTS), a strong detoxifier of carcinogens, especially from cigarette smoke. These cruciferous vegetables also contain zeaxanthin and lutein, phytochemicals involved in reducing the risk of macular degeneration.

Broccoli

One cup of steamed broccoli supplies:

• 45 calories per cup
• 90% of the daily allowance for vitamin A in the form of beta carotene, an antioxidant.
• Over 100% of the recommended intake for vitamin C
• Excellent source of minerals such as iron, magnesium, chromium and calcium.
• Contains fair amounts of B vitamins folacin, niacin, pantothenic acid and thiamine as well as vitamin K and iron
• 25% of the daily fibre requirement

Broccoli best retains its nutrients when held near freezing and at high humidity. Therefore, depending on the freshness of your broccoli, frozen broccoli may actually be a better source of vitamin A and C and the florets contain more nutrients than the stalks. Broccoli sprouts have from 30-50 times the concentration of isothiocyanates found in mature broccoli plants. One ounce of sprouts could produce the same protective effects as 2 lbs of broccoli.

What is the smell? The sulfur compounds being released through the cooking process.

Broccoli is fabulous steamed or stir-fried, and is a healthy side vegetable for any meal. Eat it raw with a dip if you don’t like its taste.

Cauliflower

• 28 kcal per cup, cooked from fresh.
• Also contains vitamin A, but to a lesser extent than broccoli, and is a source of vitamin C and B vitamins
• Excellent source of Potassium, containing 152 mg per half cup (raw). The estimated minimum requirement is 2000 mg per day for adults.

Studies have shown that with increased storage temperatures the content of ascorbic acid in cauliflower disintegrates substantially and thus, lower storage temperatures for this vegetable is advisable. When choosing cauliflower beware of brown spots or knife marks where the brown has been cut away. These brown spots are a sign of aging and can taste and smell very unpleasant.

Kale

Kale is a “hardy” winter vegetable and is botanically a cabbage that does not form heads.

• 36 kcal per cup (cooked)
• Excellent source of Vitamin A, Potassium and Calcium.
• Especially high in vitamin C, containing 53 mg per cup.

Kale is fabulous in soups and gourmet salads. It is important to eat kale within a few days of purchasing, because the flavour can become unpleasant as it ages.

Brussel Sprouts

Brussels Sprouts is another form of cabbage which may have been discovered in the fourteenth century near Brussels (perhaps where its name originated from!).

• Brussel sprouts are packed with nutrients
• Great source of calcium, potassium, folate and vitamins C and A.
• contribute only 60 kcal per cup (cooked). (More if you add butter or oil.)

When cooking Brussels sprouts cut a small cross in the stem end of each sprout (speeds cooking) and trim the tough outer leaves. In a heavy saucepan melt 1 tbsp of butter or olive oil with a finely chopped clove of garlic and toss the sprouts over high heat.

Cabbage

Cabbage is one of the oldest vegetables being used by Middle Eastern civilizations 4000 years ago. This vegetable is an important source of vitamins and minerals. These nutrients are best retained at moderate humidity and at constant temperatures close to freezing.

• great source of potassium, vitamin C and A, and contains 1/6 of an adult’s daily requirement for calcium (160 mg per cup).

Bok Choy, a Chinese cabbage, is becoming increasingly popular, due to its sweet and mild flavor. It is excellent stir-fried with other vegetables and served on a bed of brown rice.

Watch for the Eating for Energy segment every Tuesday on BCTV’s Noon News Hour!