i. Types of vegetables
ii. Nutritive value of vegetables
iii. Factors affecting the choice of vegetables
iv. Cooking method for fruits and vegetables
v. Salads, garnishing desert
SUBJECT: FOOD AND NUTRITION
CONTENT: (i) Types of vegetables
- Nutritive value of vegetables
- Factors affecting the choice of vegetables
- Cooking method for fruits and vegetables
- Salads, garnishing desert
SUBTOPIC 1: Types of vegetables, Nutritive value of vegetables
Definition of vegetables
Vegetables are edible parts of plants which are meant for human consumption. These edible parts can be consumed raw or cooked and they include flower, roots, stem, leaves, etc. They are highly nutritious because they supply the body with essential nutrients which enable the body to function properly:
They contain fibres(cellulose) that act as roughages that aid bowel movement and prevents many types of disease. They also add colour and palatability to a simple meal. The perishable vegetables especially can be preserved or stored in the refrigerator or other scientific methods.
Vegetables in our locality
There are seven classes
- Fruit vegetable – tomatoes, koru, etc
- Green leaf vegetable – water crest (water leaf), lettuce, fluted pumpkin in leaf (ugu), bitter leaf, African spinach (green) etc.
- Roots – carrots, Swedes, turnips, parsnips etc
- Seed vegetable – green beans, lentils, soybeans
- Tuber vegetable -Irish potatoes, sweet potatoes etc.
- Bulbs vegetable – cucumber, garden egg, onions, broad leaf, pumpkin etc.
Nutritive value of vegetables
Generally, vegetables are rich in vitamins and minerals. Green leaf vegetables are god source of vitamin and beta carotene (pro vitamin A). The amount of these vitamins in each vegetable varies but dark green leaves contain more vitamins than vegetables whose leaves are pale green.
Dark- -green- leaf vegetable contain a high amount of calcium and iron but some anti-nutrients (phytate and oxalate) in vegetable often make them not be readily available to the body. Vegetable contains the B-complex vitamins especially riboflavin (vitamin B2). They contain small amount of protein (about 5% for green vegetables). They also supply the body with fibres which are cellulose that acts as roughages that aid bowl movement (easy defecation).
SUBTOPIC 2: Factors to consider when choosing vegetables
- Green leafy vegetables should look crisp and fresh with a natural attractive colour
- Their mid ribs should not be limp, but should snap sharply when broken
- When a bunch of green leaf vegetable is shaken, the leaves should not drop.
- They should be free from signs of insect attack
- Roots and tuber vegetables should be free from sand and soil.
- When buying roots or tuber vegetables, choose medium size ones instead of very small or very large ones.
- There should be no sign of rot or decay on the skin of thee vegetables
- Choose those that are free from bruises caused by harvesting implements. They should be firm and smooth when touched not rough and wrinkle.
- They should be firm and snap sharply when broken with the finger, e.g. okro
- They should be covered with dry skin to protect the vegetable e.g. onion, garlic.
- They should moderately ripe, not overripe or under ripe.
- They should be free from insect attack i.e. not showing any sign of maggot opening.
- Flower vegetables should have bright colour.
Conservative cooking methods of fruits and vegetables.
Conservative cooking method are those methods employed in cooking so as to conserve the nutrients such methods include: steaming, baking etc.
Precautions to observe when cooking leafy vegetables
- Choose a suitable size of pot for the bulk of vegetables
- There should be tight fitting lid to prevent evaporation which may cause the vegetable to burn.
- Use of potash to improve the green colour of vegetables should be minimized as it affects the B-complex vitamins.
- Green-leafy vegetables should be added prevent loss of nutrients especially vitamin C.
- Wash the vegetables several times to remove dirt, sand and debris.
- Wash before cutting to minimize loss of nutrients.
- Avoid overcooking vegetables, it impairs colour and flavour and destroy vitamin C
- Use nutrient-conserving methods to cook vegetable e.g. steaming, baking etc.
- Precaution to observe when cooking other vegetables
- Put enough water to cover the vegetable
- Maintain the boiling points throughout cooking period
- Prevent delay in the cooking time by adding salt at the last cooking stage
- The use of local potash to hasten the cooking of some vegetables should be minimized as it affects the B complex vitamins. To reduce cooking time, vegetable should be soaked in water before cooking
- Peel root and tuber vegetable as thin as possible
- Do not soak peeled vegetable in water for a long time; rather, soak in salted water to reduce discolouration.
- Cooking some root and tuber vegetable with skin help to retain their nutrients e.g yam, cocoyam, three leaf yam etc
Differences between fruits and vegetables
||Most fruits are sweet because they contain a simple sugar called fructose
||Most vegetables are less sweet because they have less fructose
||Fruit is eaten as appetizer
||Vegetables are foods that are eaten as part of or an accompaniment
||Most fruits are sweet, start or thirst quenching
||Vegetables have strong bland or natural taste
||Fruits grow on plant
||Vegetables do not
||Fruits can be eaten raw
||Most vegetables are always eaten after cooking
||Some fruits are mostly perennial plants
||Some vegetables are annual plants
||Fruits are consumed when fully ripe
||Vegetables are better eaten tender
||Fruits are the sweet ripe ovaries of a seed-bearing plant
||Vegetable is a herbaceous plant, cultivated for an edible part (seed, root, stem, leaf bulb, tuber non sweet fruits)
||A fruit can be a vegetable
||A vegetable cannot be a fruit
SUBTOPIC 3: Salad Garnishing Deserts (practical)
Salads are prepared from different food stuffs. The most popular ones are those containing raw green plants cooked vegetables may be used when fresh ingredients are not available. Fruits such as avocado pears, orange and grape fruit may be included as they add interest, varieties and flavour to the dish.
Salad can be classified as follows:
- Green salads compose of: lettuce, cucumber, fruit tomatoes, French dressing
- Cold-cooked-vegetable salad
The vegetables are neatly cut up and mix with the dressing
This consist of one vegetable only, such as potatoes tomatoes, cucumber, etc with a French dressing
- Salad with distinctive characters
e.g. fish, meat, chicken or cheese etc. These form the chief ingredients and they are mixed with the usual salad vegetables
this sort of salad is served as a separate course with a dressing.
- Fruit salad -Fresh or tinned fruit may be used
Uses of salad
- As an accompaniment to a hot pot or poultry e.g. a green salad with a French dressing.
- As an accompaniment to cold meat e.g. green salad with French dressing or mayonnaise sauce
- As a luncheon or supper dish, when the salad contains a protein food. It is served as salad cream or mayonnaise
- As an hor d’oeuvre
- As fruit salad served as a sweet course
Salad food value
- Green and yellow vegetables contain ‘A’ as the vegetables eaten raw, vitamin ‘C’ is not lost.
- Cellulose in the form of roughages help the body to get rid of waste matter
- The flavour of the salad stimulates the digestive juices
- Oil and egg used in the dressing increases the food value. Protein and starchy foods are added to the food value.
Preparation of Salad (coleslaw)
- 1 cabbage (medium size)
- 1 tomato (fruit)
- 2 fingers of carrot
- ½ finger green pepper
- 2 table spoon salad cream
- Shred finely the inner white leaves of teh cabbage.
- Wash in salted water. Drain in a colander
- Cut fruit tomatoes in slices
- Wash carrot and cut in slices or cubes
- Wash all in a plastic container and put inside fridge to cool. Serve
Precaution before preparing and garnishing salads
- Use only crisp and sound ingredients
- Wash salad vegetables thoroughly, removing all coarse and withered vegetables, separating leaves and wash them in several changing of water
- Soak anything likely to contain insect and worms for a short time in cold salt water.
- Drain very well in a colander and shake in a salad basket or in a clean cloth
- Lettuce can be kept in a wet cloth or in a refrigerator receptacle to keep it crisp
- Cook vegetables such as potatoes, yam, carrot etc, they should be tender, but firm enough to be cut into neat slices or dishes.
- Tear lettuce or cut with a silver or stainless ironic, but serve whole if possible as vitamin c is destroyed by cutting.
Shred cabbage finely; only the tender inside part should be used.
- Use ingredients of the best quality for dressing and add this to the salad just before serving. The most popular dressings are mayonnaise, French dressing and cream salad dressing. New varieties are now offered commercially.
- To give a slight flavour of onions, rub a cut onion round the inside of the salad bowl.
- Arrange the ingredients daintily in a salad bowl and keep the rest parts for garnishing. There should be some of each ingredient in the garnish to indicate that is in the salad.
- Explain best ways to prepare salad
- List 5 classes of salad
- State 5 uses of salad
- Write 3 importance of salad to human
- State three methods of cooking vegetables for nutrient-conservation
- List four (4) differences between fruits and vegetable
- Write (2) precautions to observe when cooking vegetable.
- State the factors affecting the choice of vegetable.
- List two factors for choosing green leaf vegetable
- Explain the importance of medium-sized vegetables in diet.
- Explain 2 precautions before preparing salad
- State why salad vegetable should be soaked before using them
- List 2 important dressings for salad
- One of the following is not the classes of food vegetable. (a) leaf (b) root (c) maize (d) tuber
- Leafy vegetables do not contain one of the following. (a) calcium (b) iron (c) B complex (d) fat
- __________ is an example of a tuber vegetable.
- Green-leaf vegetable should be added at the stage of cooking. (a) true (b) false (c) none of the above (d) all of the above
- _________ is not a nutrient-conserving method of cooking vegetable. (a) stewing (b) boiling (c) baking (d) steaming
- One of the following is not in the class of vegetable. (a) leaf (b) root (c) maize (d) tuber
- Leafy vegetables do not contain one of the following. (a) calcium (b0 iron (c) B- complex vitamins (d) fat
- __________ is an example of a tuber vegetable. (a) bitter leaf (b) Irish potatoes (c) cauliflower (d)okro
- Green leaf vegetable should be added at the last stage of cooking.
- ___________ is not a nutrient-conserving method of cooking vegetables
Read Evans food and nutrition for senior secondary school book 2 by F.A. Bakare et al page (33 – 36)
– Read kitchen equipment and utensil
- Identify different kitchen equipment for various task
- List 3 large equipment and 2 small ones.
- The student cookery book by Enid O Reilly – Wright (page 95 – 100)
- Evans food and nutrition for senior secondary school book 2 by F. A. Bakare et al; Evans Brothers Nigeria Limited.