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Chapter 10Understanding Vegetables

Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 1Controlling Quality Changes During CookingCooking affects vegetables in four ways. It changes the following:TextureFlavorColorNutrientsCopyright 2014 John Wiley and Sons, Inc. All rights reserved. 2Controlling Quality Changes During CookingFiber The amount of fiber varies:In different vegetables.In mature vs. younger vegetables.In different parts of the same vegetable.Fiber is made firmer by acids and sugars.Fiber is softened by heat and alkalis.

Controlling Texture ChangesCopyright 2014 John Wiley and Sons, Inc. All rights reserved. 3StarchDry starchy foods must be cooked in enough water for the starch granules to absorb moisture and soften (gelatinize).Moist starchy vegetables have enough moisture of their own to soften (gelatinize) the starch granules.They must still be cooked until the starch granules soften.

Controlling Quality Changes During CookingCONTROLLING TEXTURE CHANGES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 4DonenessA vegetable is said to be done when it reaches the desired degree of tenderness.Some, such as winter squash, eggplant, and braised celery, are considered properly cooked when they are quite soft.Most vegetables are best cooked very briefly, until they are crisp-tender or al dente (firm to the bite).

Controlling Quality Changes During CookingCONTROLLING TEXTURE CHANGES (CONTD)

Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 5Flavor loss can be controlled in four ways:Cook for as short a time as possible.Use boiling salted water:Starting vegetables in boiling water shortens cooking time.The addition of salt helps reduce flavor loss.Use just enough water to cover food to minimize leaching of flavor, color and nutrients.Steam vegetables whenever appropriate:Reduces leaching out of flavor.Shortens cooking time.

Controlling Quality Changes During CookingCONTROLLING FLAVOR CHANGESCopyright 2014 John Wiley and Sons, Inc. All rights reserved. 6Cooking 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.Try to serve young, fresh vegetables that have been stored as short a time as possible.Controlling Quality Changes During CookingCONTROLLING FLAVOR CHANGES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 7Controlling Quality Changes During CookingCooking produces certain chemical changes. As long as the vegetables are not overcooked, this change is desirable.Overcooking produces undesirable changes.Especially in members of the cabbage family.They develop a strong, unpleasant flavor.

Controlling Color Changes Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 8Controlling Quality Changes During CookingWhite VegetablesPigments are compounds that give vegetables their color.Pigments called anthoxanthins (an-tho-zan-thins) and flavonoids range from pale yellow to white.White pigments stay white in acid and turn yellow in alkaline water.CONTROLLING COLOR CHANGES (CONTD)

Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 9Red VegetablesRed pigments, called anthocyanins, are found in only a few vegetables, mainly red cabbage and beets.Acids turn anthocyanins a brighter red.Alkalis turn anthocyanins blue or blue-green (not a very appetizing color).Controlling Quality Changes During CookingCONTROLLING COLOR CHANGES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 10Green VegetablesChlorophyll is present in all green plants.Acids are enemies of green vegetables.Both acid and long cooking turn green vegetables a drab olive green.

Controlling Quality Changes During CookingCONTROLLING COLOR CHANGES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 11Green Vegetables (contd)Protect the color of green vegetables by:Cooking uncovered to allow plant acids to escape.Cooking for the shortest possible time. Properly cooked green vegetables are tender crisp, not mushy.Cooking in small batches rather than holding for long periods in a steam table.Do not use baking soda to maintain green color.Alkalis destroy vitamins and makes texture unpleasantly mushy and slippery.Controlling Quality Changes During CookingCONTROLLING COLOR CHANGES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 12Yellow and Orange Vegetables Carotenoids are yellow and orange pigments:These pigments are very stable.Little affected by acids or alkalis.Short cooking prevents dulling of the color and preserves vitamins and flavors.

Controlling Quality Changes During CookingCONTROLLING COLOR CHANGES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 13Controlling Quality Changes During CookingSix factors are responsible for most nutrient loss:High temperatureLong cookingLeaching (dissolving out)Alkalis (baking soda, hard water)Plant enzymes (which are active at warm temperatures but destroyed by high heat)OxygenControlling Nutrient LossesCopyright 2014 John Wiley and Sons, Inc. All rights reserved. 14Cooking in a Little Liquid Versus a Lot of LiquidUsing a lot of liquid increases vitamin loss by leaching.Using a little liquid increases cooking time.Tests have shown that, for these reasons, no more nutrients are lost when vegetables are cooked in a lot of water than when vegetables are cooked in just enough water to cover.For green vegetables, a lot of water is desirable.Controlling Quality Changes During CookingCONTROLLING NUTRIENT LOSSES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 15Controlling Quality Changes During CookingDo not overcook.Cook as close to service time as possible, and in small quantities.Avoid holding for long periods on a steam table.If the vegetable must be cooked ahead of time:Undercook slightly and chill rapidly.Reheat at service time.

General Rules of Vegetable Cookery

Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 16Never use baking soda with green vegetables.Cut vegetables uniformly for even cooking.Start with boiling, salted water when boiling green vegetables and other vegetables that grow above the ground.Roots and tubers are started in cold, salted water for more even cooking.Cook green vegetables and strong-flavored vegetables uncoveredControlling Quality Changes During CookingGENERAL RULES OF VEGETABLE COOKERY (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 17To preserve color:Cook red and white vegetables in a slightly acid (not strongly acid) liquid.Cook green vegetables in a neutral liquid.Do not mix a batch of freshly cooked vegetables with a batch of the same vegetable that was cooked earlier and kept hot in a steam table.Controlling Quality Changes During CookingGENERAL RULES OF VEGETABLE COOKERY (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. 18ColorBright, natural colorsAppearance on plateCut neatly and uniformly. Not broken upTextureCooked to the right degree of donenessFlavorFull, natural flavor and sweetness

Controlling Quality Changes During CookingStandards of Quality in Cooked VegetablesCopyright 2014 John Wiley and Sons, Inc. All rights reserved. SeasoningsLightly and appropriately seasoned.SaucesButter and seasoned butters should be fresh and not used heavily.Vegetable combinationsFlavors, colors, and shapes should be pleasing in combination.

Controlling Quality Changes During CookingSTANDARDS OF QUALITY IN COOKED VEGETABLES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. Handling VegetablesWashing and SoakingWash all vegetables thoroughly:Root vegetables should be scrubbed with a stiff vegetable brush.Wash green, leafy vegetables in several changes of cold water.After washing, drain well and refrigerate lightly covered.Do not soak vegetables for long periods as flavor and nutrients leach out.

Fresh VegetablesCopyright 2014 John Wiley and Sons, Inc. All rights reserved. Handling VegetablesPeeling and CuttingPeel most vegetables as thinly as possible.Cut vegetables into uniform pieces for even cooking.Peel and cut vegetables as close to cooking time as possible.Treat vegetables that brown easily with an acid, such as lemon juice, or an antioxidant solution or hold under water until ready to use (some vitamins and minerals will be lost).Save edible trim for soups, stocks, and vegetable pures.

FRESH VEGETABLES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. Classifying VegetablesThere are many ways of classifying vegetables:The gourd familySeeds and pods Roots and tubersThe cabbage familyThe onion familyLeafy greensStalks, stems, and shootsMushroomsOther tender-fruited vegetables

Handling VegetablesFRESH VEGETABLES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. Handling VegetablesHandling Frozen Vegetables Checking QualityTemperatureLarge ice crystalsSigns of leaking on the cartonFreezer burn

Processed VegetablesCopyright 2014 John Wiley and Sons, Inc. All rights reserved. Handling VegetablesHandling Canned VegetablesChecking QualityReject damaged cans on receipt.Puffed or swollen cans indicate spoilage.Know the drained weight.Typical drained weights are 60 to 65 percent of total contents.Check the grade.

PROCESSED VEGETABLES (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. Batch Cooking Involves dividing the food into smaller batches and cooking them one at a time, as needed.Blanch-and-Chill MethodInvolves partially cooking, chilling, and finish-cooking.It is not as good, nutritionally, as cooking completely to order, but it is almost as good.

Handling VegetablesProduction and Holding Problems in Quantity CookingCopyright 2014 John Wiley and Sons, Inc. All rights reserved. Fresh VegetablesPotatoes, onions, and winter squash are stored at cool temperatures.(5065F/1018C) in a dry, dark placeOther vegetables must be refrigerated.Peeled and cut vegetables need extra protection from drying and oxidation. Cover or wrap, and use quickly to prevent spoilage.

Handling VegetablesStorageCopyright 2014 John Wiley and Sons, Inc. All rights reserved. Frozen VegetablesStore at 0F (18C) or colder, in original containers, until ready for use.Do not refreeze thawed vegetables.LeftoversThe best way to store leftovers is not to create them in the first place.Do not mix batches.

Handling VegetablesSTORAGE (CONTD)Copyright 2014 John Wiley and Sons, Inc. All rights reserved. Handling VegetablesDried legumes are soaked for several hours before cooking to replace moisture lost in drying.Dried beans absorb their weight in water.Dried Legumes

Copyright 2014 John Wiley and Sons, Inc. All rights reserved.