Creative Vegetable Cookery

HE-482, April 1991, (Reviewed June 1998)
Pat Beck, Nutrition Specialist

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Introduction
Rate Your Vegetable Use
Why Eat Vegetables?
How To Increase Vegetables In Your Diet
Kids Who Won't Eat Vegetables?
All Vegetables Not Born Equal
The Effect Of Processing
Cooking Tips
Cooking Methods
Safety
Selection And Storage Of Vegetables
Ideas For Serving
Recipes

Virtually every national report about diet and health recommends an increase in fruit and vegetable consumption to replace foods higher in calories and fat. Spurred by these nutritional considerations, fruit and vegetable consumption continues to increase. The consumer seeks fresh or fresh-like produce that is visually appealing, full-flavored, nutritious, convenient to prepare and serve, pesticide-free and available year round at a reasonable price.

The 1995 Dietary Guidelines for Americans recommend 3 - 5 servings of various vegetables daily. One cup of raw leafy greens or 1/2 cup of other vegetables is counted as a serving. When choosing your vegetables, keep the following points in mind:

• At least every other day, have dark-green leafy vegetables, such as leaf lettuce, romaine, spinach, or kale (not iceberg lettuce or green beans), and deep-yellow vegetables such as squash, carrots or sweet potatoes (not corn).
• Eat dry beans and peas often. Count 1/2 cup of cooked dry beans or peas as a serving of vegetables or as 1 ounce of the meat group.
• Include starchy vegetables, such as potatoes and corn.

Rate Your Vegetable Use:

• How many vegetables do I include daily in my diet?
• Four ways I prepare vegetables are:
• Six vegetables I frequently use in my home are:
• If there is liquid left on my cooked vegetables, I:

Why Eat Vegetables?

Vegetables are versatile, nutritious, colorful and flavorful. Vegetables are naturally low in calories, fat and sodium and are good sources of important vitamins, minerals and dietary fiber. Vegetables do not contain cholesterol. Increasing vegetable consumption can replace foods higher in calories and fat.

Vegetables are rich sources of vitamins, particularly A and C. The value of a vegetable as a source of a nutrient is affected both by the amount of the nutrient present and by the amount of the vegetable eaten. Thus, carrots, leafy green vegetables and sweet potatoes are good sources of vitamin A because they contain a large amount of vitamin A. Likewise, peppers and tomatoes are good sources of vitamin C because of high concentrations. On the other hand, potatoes, while lower in vitamin C, are also a good source of the nutrient because large amounts of potatoes are eaten. Other vegetables are good sources of folic acid, niacin, thiamin and vitamin B-6. (See Table 1.)

Table 1. What are the Good Sources?

(1) A selected serving contains (+) 10-24 percent of the U.S. RDA for 
    adults and children over 4 years of age, (++) 25-39 percent of the
    U.S. RDA for adults and children over 4 years of age, (+++) 40 
    percent of the U.S. RDA for adults and children over 4 years of age. 
(2) A selected serving contains at least + 200-349 milligrams.
(3) A single serving size contains at least 2 grams of dietary fiber.

Vegetables are relatively high in mineral content, particularly potassium, magnesium, iron and calcium. However, the amount of these minerals in vegetables is not always a good indicator of their nutritive value to the person who eats them, since some of the minerals present may not be available for the body to use. The so-called bioavailability of a nutrient depends on its form and also on the presence of other substances which may bind or hold the mineral, keeping it from being used by the body.

Vegetables are a good source of total dietary fiber and rich in soluble fiber. Soluble fiber has been generally considered responsible for many of the beneficial effects of vegetables in reducing cholesterol.

Eating foods with a variety of fiber is important for proper bowel function and can reduce symptoms of chronic constipation, diverticular disease and hemorrhoids. Populations like ours, with diets low in dietary fiber and low in complex carbohydrates (starches), and high in fat (especially saturated fat), tend to have more heart disease, obesity and some cancers. Just how dietary fiber is involved is not yet clear.

Some of the benefit from a higher fiber diet may be from the food that provides the fiber, not from fiber alone. Also, some parts of the fiber may bind or hold onto minerals, making them less available for use (digestion and absorption). Therefore, it is important to get fiber from foods rather than from supplements, and to get adequate minerals so you can maintain a healthy balance.

Cruciferous vegetables such as broccoli, brussels sprouts, cabbage, cauliflower and kohlrabi have been shown in studies with laboratory animals to be protective against certain forms of cancer. These vegetables contain substances called indoles which may act as antioxidants.

Antioxidants may prevent unwanted cell changes from occurring. Beta carotene (which the body converts to vitamin A) and vitamin C are two other antioxidant compounds which are abundant in vegetables.

Vegetables are low in protein and the protein they do contain is of less value than animal protein. This is of little concern when protein from animal sources is a normal part of the diet.

How To Increase Vegetables In Your Diet

Try one new vegetable a week. Even though people have become more conscious of nutrition, studies show that most do not eat even the minimum number of recommended servings. If you are among that group, you may need some ideas and a plan to help you gradually increase the vegetables in your diet.

Consider some of the following options:

• Keep washed, ready-to-eat vegetables on hand and easy to get at. How many times does someone in your family open the refrigerator door to see what there is to eat, and take one of the first foods they see? So let the cleaned vegetables be seen first. Also, set them out when meals and snacks are eaten.
• On the run? Take a bag of vegetables with you to munch on, or stop in the produce department to see if there are cut up vegetables ready to eat for a snack. Light colored vegetables like celery, iceberg lettuce or zucchini make good low calorie snacks or fillers even though they offer few other nutritional benefits. Keep in mind, however, that even these small amounts of nutrients in a varied diet contribute to the total.
• Serve vegetables with other favorite foods. For instance, serve a mixed vegetable salad or raw vegetable plate with pizza or hamburgers.
• Add vegetables to other foods: Put tomato slices, sprouts, and greens such as spinach or lettuce into a sandwich; Mix pasta or rice with summer squash (like zucchini), red pepper strips or broccoli florets; Add a layer of spinach to lasagna; Grate zucchini or carrots into meat loaves and hamburgers.
• Add something to vegetables: Sprinkle with Parmesan cheese or top with a melted low-fat cheese or white sauce made with low-fat milk. See recipe for white sauce on page 17; Spread with a little cream cheese. Try the Mock Cream Cheese on page 19; Make a dip by blending nonfat or low-fat cottage cheese (or reduced calorie mayonnaise) with a few tablespoons of lite salad dressing (or with dry salad dressing or soup mix); Serve a tomato salsa that has plenty of additional vegetables in it.
• Try the different methods of cooking vegetables discussed in this circular.

Give some thought to what you choose to do with the vegetables you are serving. If you end up adding too much fat, sodium or calories, you may be defeating your purpose. The popular baked potato makes a good example. A large baked potato has 140 calories. Look at the chart below to see what happens to it as we dress it up.

At this point the potato is only 31 percent of the total calories with most of the remaining 69 percent coming from fat.

You started with a 140 calorie potato, a trace of fat and 8 milligrams of sodium. Depending on the type of margarine or butter you used, you may have raised the sodium of this vegetable from under 10 to over 400 milligrams. An alternative would be to top the baked potato with two tablespoons nonfat or low-fat cottage cheese mixed with chives, Worcestershire sauce and a little mustard for less than 25 calories, a trace of additional fat and about 115 milligrams sodium.

Kids Who Won't Eat Vegetables?

Maybe you are fortunate enough to have a child or even children who love vegetables. But it is probably safe to say that for many people, getting children to eat vegetables is a perennial problem.

In her book How to Get Your Kid to Eat...But Not Too Much, Ellyn Satter, R.D., A.C.S.W., makes the following observations and suggestions.

Parents' attitudes regarding a food can be passed on to the child. Are you a parent who is not particularly fond of vegetables and is it showing? Children will generally learn to enjoy foods, even vegetables, that they see others enjoy in a pleasant mealtime atmosphere.

Offer vegetables again and again. If the child sees them often enough he will try them. However, refrain from pushing and prodding the child to try them. Just offer them at a later time.

Parents can be overanxious. Take a look at your approach. Satter suggests the tactic of "simply matter-of-factly presenting vegetables (and all other foods) to children, eating the food yourself, and letting children approach them on their own. In that way, eventually they learn to like them. If you try to force vegetables on your child, about the best you can hope for is that eventually he will grow up and eat his vegetables because he should, just like you do."

Until your child accepts a variety of vegetables in his diet, offer other sources of Vitamin A.

Keep in mind that serving sizes for a child are smaller than those for adults. A general guideline for a toddler and preschooler to be well-nourished is a serving size of about one tablespoon of vegetable per year of age. For example, two tablespoons of peas would be considered a serving for a two year old child. More specifically, for children a serving is 1/3 to 2/3 cup of juice, 2 to 4 tablespoons cooked vegetables, or 1/2 to 1 whole carrot or tomato.

Remember that children approach all new foods pretty much the same, including vegetables.

All Vegetables Not Born Equal

Raw vegetable products do not all contain the same nutrition. They vary according to variety, genetic potential, growing conditions, maturity at harvest, handling and storage conditions after harvest and amount of processing.

The Effect Of Processing

Consumers can buy at least 130 different canned vegetable products, from artichokes and asparagus to turnips and zucchini. A recent study by the U.S. Department of Agriculture and National Food Processors Association noted that canned foods provide the same nutritional value as fresh grocery produce and their frozen counterparts when prepared for the table. The study compared six vegetables in three forms: home-cooked fresh, warmed canned and prepared frozen.

It was found that the levels of 13 minerals, eight vitamins and fiber in the foods were similar. In fact, in some cases the canned product contained higher levels of some vitamins than fresh produce. Some vitamins in fresh produce may be destroyed by light or by exposure to air.

Canning provides a product that can be stored at room temperature, but usually at the cost of color, flavor and texture. Better color, texture and flavor are obtained in frozen foods but maintaining them in a frozen state entails greater energy costs.

Cooking Tips

Three R's for cooking vegetables for best nutrition:

• Reduce the amount of water used;
• Reduce the cooking time;
• Reduce the amount of exposed surface by limiting cutting, paring and shredding.

Overcooking will destroy color, crispness (texture) and some nutrients of the vegetable. Do not add baking soda to retain color because this will destroy nutrients.

Cooking Methods

Microwave: Microwaving cooks foods faster than most other methods. You use little or no water for vegetables. Microwaving is an excellent way to retain vitamins and color in vegetables. Follow the manufacture's directions for best results.

Steam: Steaming is a good method for cooking fresh or frozen vegetables. Try this method for vegetables such as asparagus, broccoli, carrots, spinach and summer squash. Use a vegetable steamer or colander to hold vegetables above the water. Place steamer in pot with a little boiling water and cover. Cook until the vegetables are just tender-crisp to preserve color and vitamins.

Steaming under pressure (pressure cooking) can be useful for cooking roots (beets, carrots, parsnips, rutabagas, turnips), tubers (white potatoes, sweet potatoes, jicama, Jerusalem artichokes) and dried legumes (peas and beans) that usually require a longer cooking time. Overcooking can easily occur so it is important to follow directions.

Stir-fry: Stir-frying is quick, easy and preserves the crisp texture and bright color of vegetables. Heat wok or heavy skillet, add just enough oil to lightly coat bottom of pan or use a small amount of some other liquid, such as a low sodium broth. Add small pieces of vegetables and stir constantly while cooking. Cook until the vegetables are bright, glossy and tender-crisp. Do not over-cook.

Pan: Panning is a method of cooking with very little water or with the steam formed by the vegetable's own juices. The vegetable is shredded or cut into small pieces and placed in a heavy pan with a small amount of cooking oil, that is, just enough to lightly coat the bottom of the pan. A tight-fitting lid is used to hold in the steam. Five to 8 minutes is all that is required to cook the vegetables tender-crisp.

Some vegetables suited for panning include shredded cabbage, carrots, sliced summer squash, thinly-sliced green beans and most leafy greens.

Bake: Baking is done in an oven with dry heat. This is an excellent method to keep vitamins, minerals and flavors in the vegetables. Some vegetables suited to this method include potatoes, sweet potatoes, winter squash and onions. Simply wash thoroughly, prick skins and place vegetables on a baking sheet in the oven.

Boil: Vegetables are cooked in a minimum amount of hot liquid, usually water. A general guideline is about one cup of liquid for four servings. The liquid left after cooking can be used as a sauce base, in soups or gravies.

Bring liquid to a full boil, add the prepared vegetables, cover and return to boiling. Reduce heat and complete cooking at a gentle boil. Vegetables cook as rapidly at a gentle boil as at a rapid boil because the temperature is 212 degrees Fahrenheit in both cases.

Additional Methods: Vegetables can be cooked by broiling, grilling, braising, pan-frying and deep-fat frying.

Safety

Several consumer studies have reported growing concern about the safety and healthfulness of the food supply. At the same time we have strong evidence that fruits and vegetables can lower the risk of some cancers and heart disease, as part of a high-fiber, low-fat diet. Perhaps some of the following information can help you put the information you receive into perspective.

Pesticide residues are monitored by the government. Studies of foods prepared for consumption have found no detectable residues in more than half of the samples tested. More than 99 percent of the samples tested had levels below the tolerance levels set by the Environmental Protection Agency (EPA). These tolerance levels have wide built in safety margins.

A National Research Council, 1989 report, which advocates the reduction of the use of externally applied chemicals, suggests that, "Based on the available data, pesticide residues in the average diet do not make a major contribution to the overall risk of cancer for humans."

Debate continues in the area of pesticide use, regulation and testing. However, while the debate goes on, you can do several things to minimize any potential risk and increase the added benefits of vegetables in your daily diet.

As you add vegetables to your diet, consider the following tips and decide what you can do that feels right for you.

• Eat a varied diet so no single food and its contents (whether natural or added) dominates.
• Buy produce in season and buy locally grown produce when possible. Locally grown and pick-your-own produce is less likely to have been treated to prevent spoilage during shipping and storage. This is not to say that these products are produced with no chemicals. You can ask the grower about the production.
• Buy organic produce. It may cost more, be less available and not as attractive as non-organic produce. Keep in mind that these also need thorough cleaning. North Dakota is one of only a few states that has legal standards to qualify a product to be labeled as organic. Regulations on a national level should be in place within the next couple of years.
• Grow your own vegetables and preserve at home.
• Remove outer leaves of leafy vegetables such as cabbage and lettuce.
• Thoroughly wash and rinse vegetables. Scrub with a brush if possible. Lift vegetables out of wash water rather than draining the water off of vegetables. DO NOT USE SOAPS OR DETERGENTS.
• Peel produce if appropriate, but realize that some pesticides are systemic and are found throughout all plant parts. Also, many nutrients are found in the skin of the vegetables.
• Cooking may further reduce the concern in some cases.

CAUTION: Vegetables are low acid foods and when they are canned they must be pressure processed at the recommended amount of pressure for the recommended amount of time if they are to be considered safe. This caution holds true for many mixtures of tomatoes with other vegetables. Contact your county extension office for current recommendations and tested recipes for these products.

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[Selection And Storage Of Vegetables]
[Ideas For Serving]
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HE-482, April 1991 (Reviewed and Reprinted June 1998)