Published on March 4, 2008
Slide1: Chapter 16 Understanding Vegetables Chapter Objectives: Chapter Objectives 1. Describe the factors that influence texture, flavor, color, and nutritional changes when cooking vegetables. 2. Cook vegetables to their proper doneness. 3. Judge quality in cooked vegetables, based on color, appearance, texture, flavor, seasonings, and appropriateness of combination with sauces or other vegetables. 4. Perform the pre-preparation tasks for fresh vegetables. 5. Calculate yields based on trimming losses. 6. Determine the quality of frozen, canned, and dried vegetables. 7. Prepare vegetables using the batch cooking method and the blanch-and-chill method. 8. Store fresh and processed vegetables. Vegetables: Vegetables Were at one time, abused, neglected, and unimportant. Today, vegetables are appreciated for their nutrition, variety, flavor, eye appeal, and sophistication. Vegetables are highly perishable. Controlling Quality Changes During Cooking: Controlling Quality Changes During Cooking Cooking affects vegetables in four ways: Texture Flavor Color Nutrients How much is changed of each will determine the final products quality. Controlling Texture Changes: Fiber - Fiber structures of vegetables (including cellulose and pectins) give them shape and firmness. Fiber is made firmer by acids and sugars. Fiber is softened by heat and alkalis. Starch is another vegetable component that affects texture Dry starchy foods must be cooked in enough water to absorb moisture and soften Moist starchy vegetables have enough moisture of their own but must be cooked to be eaten Doneness A vegetable is done when it has reached its peak degree of tenderness. Most vegetables are best cooked al dente (firm to the bite). Cooked vegetables cannot be kept hot very long. Controlling Texture Changes Controlling Flavor Changes: Controlling Flavor Changes Cooking produces flavor loss. To keep to a minimum: Cook as short a time as possible Use boiling salted water Add only enough water to cover vegetables Steam vegetables when appropriate Strong Flavored Vegetables - When cooking strong flavored vegetables, cook uncovered and with lots of water. Strong flavored vegetables are from the onion and cabbage families or root vegetables. Cooking Produces Flavor Changes: Cooking Produces Flavor Changes Some vegetables change flavors. Cook as short a time as possible Avoid overcooking because some vegetables develop a strong and unpleasant flavor when overcooked. Cooking and Sweetness: Young, freshly harvested vegetables have a high sugar content. As they mature or sit in storage the sugar turns to starch. To serve sweet-tasting vegetables: Serve young fresh vegetables that have not been stored long For older vegetables use a little sugar in the cooking water to compensate for the lack of natural sweetness Cooking and Sweetness Controlling Color Changes: White Vegetables White pigments called flavones are the primary coloring compounds in white vegetables and in the white parts of vegetables like celery, cucumbers, and zucchini White pigments stay white in acid and turn yellow in alkaline water. To keep vegetables white, add acid to the water. Red Vegetables: Red pigments called anthocyanins are found in only a few vegetable Acids turn them bright Alkalis turn them green or blue-green (not appealing) Controlling Color Changes Controlling Color Changes (cont’d): Green Vegetables- Green coloring called chlorophyll is present in all green plants. Acids turn green vegetables to a drab olive green. To protect the color of green vegetables: Cook uncovered Cook for the shortest amount of time Cook in small batches to prevent long holding times Yellow and Orange Vegetables - Yellow and orange pigments are called carotenoids, and they are very stable. They are not really affected by acids and alkalis. Long cooking times dull the color Short cooking times retain the color and vitamins and minerals Always cook vegetables in as little liquid as possible Controlling Color Changes (cont’d) Controlling Nutrient Losses: Controlling Nutrient Losses The six factors responsible for most nutrient loss: High temperature Long cooking Leaching Alkalis (baking soda, hard water) Plant enzymes Oxygen Controlling Nutrient Losses (cont’d): Controlling Nutrient Losses (cont’d) Pressure steamers cook quickly Braising uses low heat but long cooking time Baking eliminates leaching of vitamins and minerals Boiling is faster than simmering Cutting vegetables into small pieces decreases cooking time General Rules of Vegetable Cookery: General Rules of Vegetable Cookery Don’t overcook Cook as close to service time as possible If you need to cook it ahead of time undercook and chill rapidly, reheat at service time Never use baking soda with green vegetables Cut vegetables uniformly Start most vegetables cooking in boiling water, but start roots and tubers in cold water. Cook green vegetables uncovered Cook red and white vegetables in slightly acid liquid. Cook green vegetables in neutral liquid. Do not mix batches of cooked vegetables Standards of Quality in Cooked Vegetables: Standards of Quality in Cooked Vegetables Color Appearance on plate Texture Flavor Seasonings Sauces Vegetable combinations Handling Vegetables: Handling Vegetables Fresh Washing Soaking Peeling and cutting Trimming loss Classifying Vegetables as Used in the Kitchen: Classifying Vegetables as Used in the Kitchen The Gourd family (squashes) Seeds and Pods (beans, okra , peas) Tender-Fruited Vegetables (avocado, eggplant, tomatoes) Roots and Tubers (beets, carrots) The Cabbage Family (Brussels sprouts, cauliflower) The Onion Family (garlic, shallots, onions) Leafy Greens (spinach, lettuce, chicory) Stocks, Stems, and Shoots (asparagus, celery, fennel) Mushrooms Fresh Vegetables: Evaluating and Preparing: Fresh Vegetables: Evaluating and Preparing Artichokes Asparagus Avocados Bamboo Shoots Beans, Fava Beans, Fresh Shell Beans, Lima Beans, Snap Beets Bok Choy Broccoli Brussels Sprouts Cabbage, Green, Red, and Savoy Cabbage, Chinese Cactus Pads or Nopales Carrots Cauliflower Celery Celery Root or Celeriac Chayote Chestnut Corn Fresh Vegetables: Evaluating and Preparing (cont’d): Fresh Vegetables: Evaluating and Preparing (cont’d) Cucumber Eggplant Fennel Fiddlehead Fern Garlic Greens, Cabbage family (collards, turnip greens, kale) Jicama Kohlrabi Leeks Lettuce Mushrooms Okra Onions, Dry Onions, Green (scallions) Parsley Parsnips Pea Greens or Pea Shoots Peas, Green Peas, Edible Pod Pepper, Sweet Peppers, Hot, or Chiles Potatoes, white Fresh Vegetables: Evaluating and Preparing (cont’d): Fresh Vegetables: Evaluating and Preparing (cont’d) Potatoes, sweet Radishes Rutabagas Salisfy Shallots Sorrel Soybeans Spinach Squash, Summer Squash, Winter, including pumpkin Squash, Blossoms Sunchokes or Jerusalem Artichokes Swiss Chard Tomatoes Tomatillos Turnips and Rutabagas Water Chestnuts Watercress Mushrooms: Mushrooms Cultivated Exotic Mushrooms Shiitake Oyster mushrooms Enoki mushrooms Cremini Mushrooms Portobello Mushrooms Wild Mushrooms Morel Bolete Chanterelle Black trumpet Processed Vegetables: Processed Vegetables The quality of frozen or canned vegetables never equals that of fresh Handling Frozen Vegetables Checking Quality Temperature Large ice crystals Signs of leaking on the carton Freezer burn Cooking Cook frozen vegetables from the frozen state Processed Vegetables (cont’d): Handling Canned Vegetables Checking quality Reject damaged cans in receipt Know the drained weight Check the grade Cooking Handling Dried Vegetables There are two basic types of dried vegetables: Dried Legumes Freeze-Dried and Other Dehydrated Vegetables Processed Vegetables (cont’d) Production and Holding Problems in Quantity Cooking: Production and Holding Problems in Quantity Cooking Batch Cooking Cooking in smaller batches closer to meal service Blanch-and-Chill Method Storage – Fresh and Frozen: Storage – Fresh and Frozen Fresh vegetables Potatoes, onions, and winter squash are stored at 50°-65° F in a dry place Other vegetables stored in the refrigerator Peeled and cut vegetables need extra protection from drying and oxidation Store fresh vegetables for as short a time as possible Keep refrigerators and storage areas clean Frozen vegetables Store at 0° F or cooler, in original containers, until ready to use Do not refreeze vegetables Storage – Dried and Canned: Storage – Dried and Canned Dried vegetables Store in a cool (less than 75° F) in a dry, well-ventilated place Keep well sealed and off the floor Canned vegetables Keep in cool, dry place, away from sunlight and off the floor Discard damaged cans Storage - Leftovers: Storage - Leftovers Do not create them in the first place Don’t mix batches Cool quickly, and use with caution. Remember the danger zone Slide27: Clip art images may not be saved or downloaded and are only to be used for viewing purposes. Copyright ©2007 John Wiley & Sons, Inc.