We live on vegetables whether we eat it through animal
intermediaries or directly. Root vegetables like beets, carrots, parsnips, and turnips
contain valuable amount of carbohydrate. Celery and fennel carries nutrients
between roots and leaves, potatoes and water chestnut contain starch.
Vegetables with dark green leaves like the cabbage family such like broccoli,
cauliflower, collard greens, kale, mustard greens, and spinach are rich in antioxidants,
bioflavonoid and the B vitamins. Vegetables
contain high energy sugars. It is highly recommended that we eat 5 to 10
servings of fruits and vegetables daily. A serving is a half cup of raw or
cooked vegetables, a cup of leafy salad vegetables or a half cup of juice.
Choose a variety of raw and cooked vegetables including bright colored orange,
red, dark green and yellow vegetables, vegetables from cruciferous family and
alliums vegetables such as onion and garlic. Vegetables and fruits not only
contain antioxidants and bioflavonoid but also photochemical, which helps
protect the body from diseases. Most vegetables provide an excellent amount of
vitamins, fiber, folate, potassium, as well as some other minerals. Vegetables
are low in fat and also low in calories. Chlorophyll found in green vegetables
is soluble only in fats, cooking vegetables in water liberates the enzyme
chorophyllase which breaks chlorophyll down into water-soluble components. Some
vitamins are water soluble, and are leached out into the cooking water and this
can be used for stock. Color is a useful guide to the vitamin content of
vegetables. The larger and darker the leaves are, the more vitamin C and beta
carotene they contain; the inner pale leaves of cabbage and lettuce contain
only 3 percent of the carotene found in the outer leaves but usually the outer
leaves are discarded because it’s been damaged due to exposure to pollutants
and pesticides. Deep yellow, orange or dark
green vegetables derive their color from carotenoid pigments; these include
beta carotene, an antioxidant that is converted to vitamin A in the intestinal
wall. Because these pigments are stable in cooking and soluble in fat, the
nutritional content is well preserved during baking and boiling. Soluble and
insoluble fiber in vegetables keeps bowel function regular and thereby colon’s
exposure to potentially toxic by-products of digestion although it can cause
gas and bloating in some people.
Vegetables have a protective effect that goes far beyond
what vitamin pills can offer. Most vegetables have more than one benefit for
example broccoli contains beta-carotene, Vitamin C, Fiber, folic acid, and the
phytochemical sulforaphane.
Vegetables provide starches, sugars, and proteins, their
main contributions are vitamins, minerals, fiber, and protective
phytochemicals. Their nutrient content, color, and texture are affected by the
method of preparation, the length of cooking time, and the volume of water used.
The yellow carotene pigments are not water soluble and are well preserved in
cooking, but vitamin C and the B vitamins leach into the cooking liquid.
Vitamin C is also destroyed on exposure to oxygen. Up to 20 percent of the
vitamin C in a vegetable may be lost during each minute that it takes the water
to heat from cold to boiling. This is because an enzyme that destroys vitamin C
becomes more active as temperature rises; however, it stops its destructive
action at the boiling point. For this reason, vegetables should be added to
water that is already boiling. Steaming or cooking in a small amount of water
retains more than twice as much vitamin C as boiling does.
The yellow and orange carotenoid pigments are changed
only by the high temperatures reached with pressure cooking. The attractive
brilliant green of chlorophyll in plant tissues is dulled, however, when heat
causes chemical changes. This does not matter as chlorophyll cannot affect the
human body internally since it is not absorbed. Some cooks blanch vegetables
such as beans and broccoli in boiling water for a minute or two, and then
plunge them into cold water to hold the color. This is satisfactory for
vegetables that are served cold, but if they are served hot, they require rapid
heating, with further loss of nutrients.
Most vegetables are safe to eat either raw or cooked. The
exceptions are Lima and kidney beans and other legumes, which contain toxic
substances that are inactivated through cooking. Broccoli, kale, and other
cruciferous vegetables harbor goitrogenic compounds that can interfere with
iodine metabolism. Cooking inactivates these compounds, but eating large
amounts of these vegetables raw may worsen a pre-existing thyroid condition.
Most vegetables do not provoke allergies, but some people react to members of
the night-shade family, which includes eggplants and tomatoes. Corn is another
common allergen.
To preserve the betacyanin in beets, avoid boiling them
in water, it is best to roast, bake, or microwave whole beets in their skins.
Peeled or cut-up beets leach the vegetable’s pigments (and thus the betacyanin
is lost). When beets are boiled in water it depletes their folate which is
water soluble.
How to store Vegetable:
Vegetables should not be stored for a long period of time
as they tend to lose their flavor, sweetness and texture. Corn and peas kept at
room temperature after pickling for just 6 hours will lose up to 40 percent of
their sugar content. Beans and stem vegetables like broccoli, asparagus become
tough if stored for a long period of time. Vegetables originating in warm
climates (including beans, eggplants, peppers, okra, squash, and tomatoes is
best stored at 50F (10C). Potatoes convert their starch to sugar below 40F
(4C); keep them cool and out of the light to prevent the formation of poisonous
alkaloids. The salts and sugars found in vegetable sap prevents them from
freezing until several degrees colder. Tomatoes should not be refrigerated; the
cold temperature ruins the flavor. They are best stored in a cool, dark place,
not in the fridge. Greens should be washed, drained, wrapped in paper or cloth
towels, and stored in a tightly sealed container in the fridge. If bought in
airtight packaging, store as it is. Peppers should be stored in the
refrigerator, away from sweet fruits.
Vegetables and fruit are the most important part of our diet-----eat well and you will live well.
