Controlling Quality Changes During Cooking of Vegetables

As a cook ,you have a choice of many kinds of vegetables and many cooking methods. Not surprisingly, then, you are also faced with the necessity of learning many rules for cooking vegetables.

• Many guides to vegetable cookery simply present a long list of rules to memorize. You will be able to understand the principles more easily, however, if you first learn how vegetables change as they are cooked and how to control those changes.
• In other words ,it is suggested you not just memorize what to do but understand why you do it. Cooking affects vegetables in four ways. It changes the following:
• 1. Texture.
• 2. Flavor.
• 3. Color.
• 4. Nutrients.
• How much these four characteristics change determines whether your final product is attractive and delicious to the customer or whether it ends up in the garbage. You can control these changes if you understand how they happen.
• Unfortunately, there is still legitimate controversy among chefs about proper vegetable cooking techniques. Modern technology has not yet solved all the problems that experienced chefs tackle successfully every day in the kitchen.

 

CONTROLLING TEXTURE CHANGES

Changing the texture is one of the main purposes of cooking vegetables.

FIBER

• The fiber structures of vegetables (including cellulose and pectins) give them shape and firmness. Cooking softens some of these components.
• The amount of fiber varies
• 1. In different vegetables. Spinach and tomatoes have less than carrots and turnips, for example.
• 2. In different examples of the same vegetables. Old, tough carrots have more fiber than young, fresh carrots.
• 3. In the same vegetable. The tender tips of asparagus and broccoli have less fiber than their tougher stalks.

• Fiber is made firmer by
• 1. Acids.
• Lemon juice, vinegar and tomato products, when added to cooking vegetables, extend the cooking time.
• 2. Sugars.
• Sugar strengthens cell structure.You will use this principle primarily in fruit cookery. For firm poached apples or pears, for example, cook in a heavy syrup. For applesauce, cook apples until soft before sweetening.
• Fiber is softened by
• 1. Heat.
• In general, longer cooking means softer vegetables.
• 2. Alkalis.
• Do not add baking soda to green vegetables.Not only does it destroy vitamins but
• it also makes the vegetables unpleasantly mushy.
• STARCH
• Starch is another vegetable component that affects texture.
• 1. Dry starchy foods like dried legumes (beans, peas, lentils), rice,and macaroni products must be cooked in enough water for the starch granules to absorb moisture and soften. Dried beans are usually soaked before cooking to replace lost moisture.
• 2. Moist starchy vegetables like potatoes and sweet potatoes have enough moisture of their own, but they must still be cooked until the starch granules soften.
• DONENESS
• A vegetable is said to be done when it has reached the desired degree of tenderness.
• This stage varies from vegetable to vegetable. Some, such as winter squash, eggplant, and braised celery, are considered properly cooked when they are quite soft.
• Most vegetables, however, are best cooked very briefly, until they are crisp-tender or al dente (firm to the bite). At this stage of tenderness, they not only have the most pleasing texture
• but also retain maximum flavor , color, and nutrients.
• CONTROLLING FLAVOR CHANGES
•  
• COOKING PRODUCES FLAVOR LOSS
• Many flavors are lost during cooking by dissolving into the cooking liquid and by evaporation. The longer a vegetable is cooked, the more flavor it loses.

Flavor loss can be controlled in several ways: 1. Cook for as short a time as possible. 2. Use boiling salted water. Starting vegetables in boiling water shortens cooking time. The addition of salt helps reduce flavor loss. 3. Use just enough water to cover to minimize leaching. Note that this rule contradicts rule 1 in that adding vegetables to a small quantity of water lowers the temperature more, so cooking time is extended.. 4. Steam vegetables whenever appropriate. Steam cooking reduces leaching out of flavor and shortens cooking time. Strong-Flavored Vegetables

• With certain strong-flavored vegetables ,it is desirable to lose some of the flavor to make them more appealing to the taste.      These include the onion family (onions, garlic, leeks , shallots),the cabbage family (cabbage , Brussels sprouts ,cauliflower ,broccoli),and some root vegetables (turnips, rutabagas).
• When cooking strong-flavored vegetables leave uncovered to allow these flavors to escape ,and use larger amounts of water.
• COOKING PRODUCES FLAVOR CHANGES
• Cooked vegetables do not taste like raw vegetables because cooking produces certain chemical changes. As long as the vegetables are not overcooked, this change is desirable. It produces the flavors one looks for in vegetable dishes.

Overcooking produces undesirable changes in members of the cabbage family. They develop a strong, unpleasant flavor. Cabbage and its relatives should be cooked quickly, uncovered.

COOKING AND SWEETNESS

• Young, freshly harvested vegetables have a relatively high sugar content that makes them taste sweet. As they mature ,or as they sit in storage, the sugar gradually changes to starch. This is especially noticeable in corn, peas, carrots, turnips and beets.
• To serve sweet-tasting vegetables:
• 1. Try to serve young, fresh vegetables that have been stored for as short a time as possible.
• 2. For older vegetables ,especially those just listed, add a small amount of sugar to the cooking water to replace lost sweetness.