Transcript ch16

Chapter 16
Understanding Vegetables
Copyright © 2011 by John Wiley & Sons, Inc. All Rights Reserved
Controlling Quality Changes During
Cooking
Cooking affects vegetables in four ways. It
changes the following:
1. Texture
2. Flavor
3. Color
4. Nutrients
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Controlling Texture Changes
Fiber
The amount of fiber varies:
1. In different vegetables.
2. In mature vs. younger vegetables.
3. In different parts of the same vegetable.
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Controlling Texture Changes
Fiber
Fiber is softened by:
• Heat
• Alkalis
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Controlling Texture Changes
Starch
• Dry 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.
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Controlling Texture Changes
Doneness
A vegetable is said to be done when it reaches the
desired degree of tenderness.
• Some, such as winter squash, eggplant, and braised
cabbage, 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).
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Controlling Flavor Changes
Cooking Produces Flavor Loss
Flavor loss can be controlled in several 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.
• Minimizes leaching of flavor, color and nutrients.
• Steam vegetables whenever appropriate.
• Reduces leaching out of flavor.
• Shortens cooking time.
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Controlling Flavor Changes
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.
• Try to serve young, fresh vegetables that have been
stored as short a time as possible.
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Controlling Color Changes
Cooking Produces Flavor Loss
• Cooking 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.
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Controlling Color Changes
White Vegetables
• Pigments 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.
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Controlling Color Changes
Red Vegetables
• Red 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).
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Controlling Color Changes
Green Vegetables
• Chlorophyll is present in all green plants.
• Acids are enemies of green vegetables.
• Both acid and long cooking turn green vegetables a
drab olive green.
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Controlling Color Changes
Green Vegetables
Protect the color of green vegetables by:
1. Cooking uncovered to allow plant acids to escape.
2. Cooking for the shortest possible time. Properly
cooked green vegetables are tender crisp, not mushy.
3. 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.
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Controlling Color Changes
Yellow and Orange Vegetables
• Carotenoids: 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.
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Controlling Nutrient Losses
Six factors are responsible for most nutrient loss:
1. High temperature
2. Long cooking
3. Leaching (dissolving out)
4. Alkalis (baking soda, hard water)
5. Plant enzymes (which are active at warm temperatures
but destroyed by high heat)
6. Oxygen
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Controlling Nutrient Losses
Cooking in a Little Liquid Versus a Lot of Liquid
• Using a lot of liquid increases vitamin loss by leaching.
• Using a little liquid increases cooking time.
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General Rules of Vegetable Cookery
• Do 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.
• Never use baking soda with
green vegetables.
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General Rules of Vegetable Cookery
• 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 uncovered.
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General Rules of Vegetable Cookery
• To 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.
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Standards of Quality in Cooked
Vegetables
Color
• Bright, natural colors
Appearance on plate
• Cut neatly and uniformly. Not
broken up
Texture
• Cooked to the right degree of
doneness
Flavor
• Full, natural flavor and
sweetness
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Standards of Quality in Cooked
Vegetables
Seasonings
• Lightly and appropriately
seasoned.
Sauces
• Butter and seasoned
butters should be fresh
and not used heavily.
Vegetable combinations
• Flavors, colors, and
shapes should be
pleasing in combination.
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Handling Vegetables
Washing
Wash 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.
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Handling Vegetables
Soaking
• Do not soak vegetables for long periods.
• Flavor and nutrients leach out.
• Dried legumes are soaked for several hours before
cooking to replace moisture lost in drying.
• Dried beans absorb their weight in water.
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Handling Vegetables
Peeling and Cutting
• Peel 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 trimmings for soups, stocks, and vegetable
purées.
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Handling Vegetables
Classifying Vegetables
There are many ways of classifying vegetables:
• The gourd family
• Seeds and pods
• Roots and tubers
• The cabbage family
• The onion family
• Leafy greens
• Stalks, stems, and shoots
• Mushrooms
• Other tender-fruited vegetables
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Identifying Vegetables:
Gourds and Squashes
• Squashes
– Winter
• Acorn
• Banana
• Butternut
• Pumpkin
– Summer
• Zucchini
• Yellow
Identifying Vegetables:
Pods and Seeds
• Corn
• Okra
• Legumes
– Fresh beans
• Green beans
• Haricot verts
– Dry beans
• Black beans
• Black-eyed peas
• Lentils
• Red kidney beans
• Pinto beans
• Great northern beans
Identifying Vegetables:
Roots and Tubers
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Beets
Carrots
Celery root
Jicama
Parsnips
Radishes
Rutabaga
Turnips
Water chestnuts
Identifying Vegetables:
Cabbages, Brassica
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Bok choy
Broccoli
Brussels sprouts
Cauliflower
Head cabbage
Kale
Kohlrabi
Napa cabbage
Savoy
Identifying Vegetables:
Onions
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Bulb onions
Garlic
Leeks
Scallions
Shallots
Identifying Vegetables:
Greens
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Collards
Mustard
Sorrel
Spinach
Swiss chard
Turnip greens
Identifying Vegetables:
Stalks
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Artichokes
Asparagus
Bamboo shoots
Celery
Fennel
Hearts of palm
Nopales
Identifying Vegetables:
Mushrooms and Truffles
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Chanterelle
Clam shell
Enoki
Morel
Pom Pom blanc
Porcini
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Portabella
Shiitake
Oyster
White
Truffles
 White
 Black
Identifying Vegetables:
Tender Fruiting Vegetables
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Avocados
Eggplants
Cucumbers
Peppers
– Hot
– Sweet
• Tomatillos
• Tomatoes
Purchasing Vegetables
• Vegetables are available in a variety of
forms:
– Fresh
– Canned
– Frozen
– Dried
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Purchasing Fresh Vegetables
• Sold by weight and count
• Packed in:
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Lugs
Bushels
Flats
Crates
• Some common vegetables can be purchased
preprocessed
– Trimmed
– Cleaned
– Cut to specification
Canned Vegetables
• Raw vegetables are cleaned and placed in
sealed containers, then subjected to high
heat
• Grading
– U.S. Grade A or Fancy
– U.S. Grade B or Extra-Select
– U.S. Grade C or Standard
• Canned vegetables are purchased in
cases of standard size cans
Processed Vegetables
Handling Canned Vegetables
Checking Quality
• Reject 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
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Frozen Vegetables
• Severely inhibits the growth of
microorganisms that cause spoilage
• Grading the same as canned
• IQF (individually quick-frozen)
Processed Vegetables
Handling Frozen Vegetables
Checking Quality
• Temperature
• Large ice crystals
• Signs of leaking on the carton
• Freezer burn
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Dried Vegetables
• Dramatically alters the flavor, texture and
appearance
• Loss of moisture concentrates flavors and
sugars
• Greatly extends shelf life
Production and Holding Problems in
Quantity Cooking
Batch Cooking and Blanch-and-Chill
• Batch Cooking involves dividing the food into
smaller batches and cooking them one at a
time, as needed.
• Blanch and Chill involves partially cooking,
chilling, and finish-cooking.
• It is not as good, nutritionally, as cooking completely
to order, but it is almost as good.
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Storage
Fresh Vegetables
• Potatoes, onions, and winter squash are stored
at cool temperatures.
• (50–65°F/10–18°C) in a dry, dark place
• Other vegetables must be refrigerated.
• Peeled and cut vegetables need extra
protection from drying and oxidation.
• Cover or wrap, and use quickly to prevent spoilage.
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Storage
Frozen Vegetables
Store at 0°F (–18°C) or colder, in original containers, until
ready for use
• Do not refreeze thawed vegetables.
Leftovers
• The best way to store leftovers is not to create them in the first
place.
• Do not mix batches.
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Chapter 17
Cooking Vegetables
Copyright © 2011 by John Wiley & Sons, Inc. All Rights Reserved
Boiling and Steaming
Nearly all vegetables may be cooked by boiling or
by steaming.
• Boiling and Steaming are the two most frequently used
methods for cooking vegetables.
• Easy, economical, and adaptable to a great variety of
preparations.
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Boiling and Steaming
Shocking or Refreshing: Boiled or simmered
vegetables are drained as soon as they are
cooked and then cooled quickly under cold
water.
• This method should be used unless the vegetables
are to be served immediately.
• In other cases, the product is only partially cooked by
boiling or steaming and is finished by another
cooking method, such as sautéing or baking.
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Boiling and Steaming
• In many cases, the agitation and high
temperature of boiling break up delicate
vegetables.
• Simmering is more appropriate
• Steaming as a method for cooking vegetables is
becoming more widely used.
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Boiling and Steaming
Puréeing Vegetables
Vegetable purées are served as side dishes or
garnishes.
• They are also used as ingredients in other preparations.
Rub the cooked vegetable
through a tamis using a pestle
or a plastic scraper.
Scrape the purée from
the bottom of the sieve.
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Sautéing and Pan-Frying
• Sautéing means cooking quickly in a small amount
of fat.
• The product is often tossed or flipped in the pan over
high heat.
• Pan-frying means cooking in a larger amount of fat
and for a longer time at lower heat.
• The product is not tossed or flipped in the pan over
lower heat.
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Sautéing and Pan-Frying
To flip foods in a sauté pan:
• Give the handle a sharp twist upward with the wrist.
• Be sure to move the pan back far enough to catch the
foods as they come down.
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Braising
A slow, moist-heat cooking
method using a small
amount of liquid.
• Braised vegetables are not
always cooked in fat before
liquid is added.
• Some kind of fat is used in
the preparation.
• Braised vegetable
preparations tend to be more
complex than boiled or
steamed vegetables, and the
cooking times are longer.
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Baking
Cooking starchy vegetables from the raw to the finished
state.
• Starch vegetables are baked because the dry heat produces a
desirable texture.
Vegetable casseroles are baked for either of two reasons:
• The slow, all-around heat allows the product to cook undisturbed.
• The dry heat produces desirable effects, such as browning and
caramelizing of sugars.
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Broiling and Grilling
Broiling
Used to finish cooked or partially cooked
vegetables by browning or glazing them on top.
• Bread crumbs are sometimes used to give a pleasing
brown color and to prevent drying.
• Casseroles or gratin dishes that do not brown sufficiently
in the oven may be browned for a few seconds under the
broiler or salamander.
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Broiling and Grilling
Grilling
Grilled, quick-cooking
vegetables are pleasant
accompaniments to grilled
and roasted meats and
poultry.
• Cut the vegetables into broad
slices.
• Brush with oil .
• Grill until lightly cooked and lightly
browned.
• Heavy browning may produce an
unpleasant burned taste.
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Deep Frying
Deep-fried vegetables may be divided into five
categories:
1. Vegetables dipped in batter and fried.
2. Vegetables breaded and fried.
3. Vegetables fried without a coating.
4. Small vegetables or cuts mixed with a batter and
dropped with a scoop into hot fat.
5. Croquettes: thick vegetable purées or mixtures of small
pieces of vegetable and a heavy béchamel or other
binder, formed into shapes, breaded and fried.
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Deep Frying
Vegetables for Deep-Frying
Most vegetables large enough to coat with breading or
batter may be fried.
• Tender, quick-cooking vegetables can be fried raw.
• Others may be precooked by simmering or steaming briefly to
reduce the cooking time they need in the frying fat.
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