Vegetables and Vegetable Preparation Chapter 20 Vegetables n
Vegetables and Vegetable Preparation Chapter 20
Vegetables n n Plants or parts of plants used for foods Plants or parts of plants served raw of cooked as part of main course of meal Introductory Foods, 13 th ed. Bennion and Scheule 2 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Consumption Trends n n Vegetable consumption has increased since 1970 Americans consume less than the recommended servings of vegetables per day n n n Need to increase consumption of dark green and orange vegetables and legumes See www. mypyramid. gov Americans favor starchy vegetables such as potatoes Introductory Foods, 13 th ed. Bennion and Scheule 3 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Nutrition n Vegetable consumption is associated with reduce risk of n n n Certain cancers Type 2 diabetes Stroke Potentially cardiovascular disease and hypertension 2 ½ cups of vegetables is recommended for reference 2000 Kcal diet Introductory Foods, 13 th ed. Bennion and Scheule 4 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Nutrition n Should consume n n n Dark green Orange Legumes Starchy vegetables Other vegetables Vegetables are rich in n n n Introductory Foods, 13 th ed. Bennion and Scheule 5 Fiber Folate Potassium Vitamin A Vitamin C Phytochemicals © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Kinds of Vegetables n Leaf vegetables n n n Tomatoes n Broccoli Asparagus Introductory Foods, 13 th ed. Bennion and Scheule Potatoes Seeds n 6 Garlic and onion Tubers n n Carrots Bulbs n Stems and shoots n Roots n Flowers n n Lettuce Vegetable-fruits n n n Peas © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Mushrooms n Not technically a vegetable n Are fungi n Often served “like” vegetables Introductory Foods, 13 th ed. Bennion and Scheule 7 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Purchasing Vegetables n n n Seek firm, crisp, bright in color Consider size, shape, gloss, color, absence of defects, and freshness Consider point of origin – local? Introductory Foods, 13 th ed. Bennion and Scheule 8 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Grades n Fresh, frozen, and canned vegetables may be graded n USDA has established grades n n n Grading is NOT required by law May be “Packed under continuous inspection of USDA” Manufacturers may have their own grading standards. Introductory Foods, 13 th ed. Bennion and Scheule 9 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Economic Considerations n Cost per serving n Cost per nutrients n Consider n n When in season usually better priced Compare fresh, frozen, canned Introductory Foods, 13 th ed. Bennion and Scheule 10 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Organic n n National standards for organic foods established by USDA in 2002 “Natural” and “Organic” are not the same Introductory Foods, 13 th ed. Bennion and Scheule 11 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Biotechnology n Traditional biotechnology n Plant and animal breeding n Genetic engineering n Regulated by n n n USDA FDA EPA Introductory Foods, 13 th ed. Bennion and Scheule 12 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
“Convenience” Vegetables n n Partially processed Value added Fresh cuts Packaging n n Modified atmosphere Hermetic Introductory Foods, 13 th ed. Bennion and Scheule 13 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Vegetable Storage n Short shelf life n Terminology to know n n Respiration Senescing Introductory Foods, 13 th ed. Bennion and Scheule 14 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Vegetable Storage n General conditions n High humidity conditions often best n n Loss of turgor Avoid storage by other vegetables that n n Are strongly flavored vegetables Produce ethylene gas Introductory Foods, 13 th ed. Bennion and Scheule 15 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Vegetable Storage n Temperature n n Best temperature varies with vegetable Roots and tubers usually not refrigerated Tomatoes – best flavor when stored at room temperature Many other vegetables – best stored under refrigeration Introductory Foods, 13 th ed. Bennion and Scheule 16 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Methods to Extend Storage n Coatings n n n Vegetable-oil emulsion on some vegetables Edible wax Storage n n Controlled atmosphere Oxygen levels reduced to extend storage Introductory Foods, 13 th ed. Bennion and Scheule 17 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Preliminary Preparation n Most vegetables grow near or in ground n Food safety and preparation n Select vegetables with minimum decay Thoroughly wash Avoid cross-contamination Introductory Foods, 13 th ed. Bennion and Scheule 18 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Edible Portion and Yield n n n EP – edible portion AP – as purchased Yield – the percent of the vegetable remaining after cleaning and peeling Introductory Foods, 13 th ed. Bennion and Scheule 19 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Preparation and Quality n n n n Why cook? Plant pigments Enzymatic oxidative browning Discoloration of potatoes Flavor Texture Prevention of nutrient losses Introductory Foods, 13 th ed. Bennion and Scheule 20 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Why Cook? n Improved palatability n n Consider raw vs. cooked green beans or potatoes More digestible n i. e. dried legumes n Gelatinization of starch n Destroy microorganisms Introductory Foods, 13 th ed. Bennion and Scheule 21 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Plant Pigments n Chlorophyll n n Green beans, broccoli, others Excess heat and acid = olive green color Alkaline - i. e. baking soda n n n Negative impact on nutrients and texture Promotes bright green color Carotenoids n n n Orange and red Carrots, watermelon, tomatoes Includes lycopene Introductory Foods, 13 th ed. Bennion and Scheule 22 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Plant Pigments n Anthocyanins n n n Red cabbage, radishes, black raspberries Water soluble Acid medium = red Alkaline medium = blue and purple Reacts with tin and iron Introductory Foods, 13 th ed. Bennion and Scheule 23 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Plant Pigments n Betalains n n Red (red beets) Yellow (Yellow cactus pear) Very soluble in water Anthoxanthins n n White Potatoes May combine with metals (aluminum or iron) Stable to heat but if prolonged may darken Introductory Foods, 13 th ed. Bennion and Scheule 24 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Enzymatic Oxidative Browning n Darkening of cut vegetables and fruits upon exposure to air n n n Vegetables – potatoes and sweet potatoes Fruits – bananas, apples, and peaches Prevention n n Acid solutions such as lemon juice Vitamin C Sulfur dioxide may be used for dehydrated fruits Submerge in water Introductory Foods, 13 th ed. Bennion and Scheule 25 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Discoloration of Potatoes n Some potatoes may be especially prone to darken after cooking n n Cooking in acidic liquid is preventative Cream of tartar in water Introductory Foods, 13 th ed. Bennion and Scheule 26 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Flavor n Compounds responsible for flavor n n n n Aldehydes Alcohols Ketones Organic acids Esters Sulfur-containing compounds Factors affecting flavor n n n Overcooking Amount of water used Method of cooking Introductory Foods, 13 th ed. Bennion and Scheule 27 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Cabbage Flavors n Cabbage, cauliflower, broccoli, Brussels sprouts, kale, kohlrabi, mustard, rutabaga, and turnips n Mild when raw n Develop strong flavors when overcooked n Best to cook without lid or tipped lid to vent volatile compounds Introductory Foods, 13 th ed. Bennion and Scheule 28 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Onion Flavors n Onions, leeks, garlic, and chives n Strong flavored when raw n More mild after cooking Introductory Foods, 13 th ed. Bennion and Scheule 29 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Texture n Cooking to tender-crisp recommended n Fiber components n n n Cellulose Hemicellulose Pectins Betaglucans Lignin n n A noncarbohydrate molecule Gums and mucilages Introductory Foods, 13 th ed. Bennion and Scheule 30 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Fiber - Influence of Cooking n n n Fiber not lost Cellulose softened Hemicellulose disintegrate in alkaline water Acid prevents softening Calcium salts make vegetable tissues firmer Introductory Foods, 13 th ed. Bennion and Scheule 31 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Prevention of Nutrient Losses n n Higher nutrient levels when vegetables prepared and used close to time of harvest Lost during storage n n Vitamin C and B vitamins Lost in cooking n n n Dissolving action of water Chemical decomposition (acid or alkaline) Oxidation Loss of solids into cooking water Volatilization Introductory Foods, 13 th ed. Bennion and Scheule 32 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Cooking Methods n Broiling and grilling n Boiling n n Roasting and baking n Pan-frying and deepfrying Blanching Parboiling n Steaming n Pressure cooking n Microwave cooking Sautéing Introductory Foods, 13 th ed. Bennion and Scheule 33 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Cooking of Frozen and Canned n Frozen vegetables n Canned vegetables Introductory Foods, 13 th ed. Bennion and Scheule 34 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Vegetarian Diets n n n Semi-vegetarian Pesco-vegetarian Lacto-ovo-vegetarian Lacto-vegetarian Ovo-vegetarian Vegan Introductory Foods, 13 th ed. Bennion and Scheule 35 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Dried Legumes n Dried beans, peas, and lentils n Inexpensive protein source n Rich in n n Complex carbohydrate Dietary fiber Protein Low in fat Introductory Foods, 13 th ed. Bennion and Scheule 36 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Preparation of Legumes n Must be cooked before eating n Soaking of Beans n n Soft water is preferable Use of alkali not recommended n n May make beans too soft Destructive to thiamin n Canned beans offer convenience n Raffinose and Sachyose Introductory Foods, 13 th ed. Bennion and Scheule 37 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
Soybeans n Good source of protein n Soy products n n n Texturized soy proteins Whole soybeans Soy milk Tofu Fermented soy products Introductory Foods, 13 th ed. Bennion and Scheule 38 © 2010 Pearson Higher Education, Upper Saddle River, NJ 07458. • All Rights Reserved.
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