Vegetable and fruit cookery
Vegetables are very rich source of vitamins and minerals that are responsible for the functioning of our bodies’ basic metabolism. The main sources of vegetables are plants. Any part of plant that can be consumed by human body in any form is known as vegetable. Vegetables are also a very good source of carbohydrates, proteins and fats. Fibers that are also known as roughage is provided by vegetables in the form of salads.
Plants are the main source of vegetables but it is not just one part of plant that can be used as vegetable. Different parts of plants provide a variety of vegetables.
Vegetables are classified into different categories as under:
1. Roots & Tubers: Roots are the extended parts of stem that goes under-ground and supplies nutrients (through water) to the plant. Tubers are fat underground stems contains more starch. Examples: Radish, Carrot, Onion, Potato, Beetroot.
2. Stem: Stem is a good source of fiber (Cellulose). Examples: Asparagus, celery, lotus stem.
3. Leaves: Rich source of minerals. Examples: Cabbage, spinach, mustard leaves, lettuce.
4. Flower: Examples: Cauliflower, broccoli.
5. Fruits: Most of the vegetables are fruits. Examples: Tomatoes, brinjal, Ladyfinger, lemon.
6. Seeds: Examples: Peas. Mustard seeds, fenugreek.
Pigments and Colour Changes
The colour of the vegetable is because of the pigment present in it. The different types of pigments give variety of colours to the vegetables. The colours of the vegetables are important from presentation point of view. Pigments give eye appeal to the dish. A chat should know the effect of cooking on vegetable pigments than only one can preserve the natural colour of vegetables. Different types of pigments are:
Green colour vegetables contain chlorophyll. It is of two types: ch-a and ch-b. it is an organic easier that contains Mg. It is slightly soluble in water and soluble in many organic solvents.
– In alkaline medium it changes to bright green. ln alkaline medium easters undergo hydrolysis forming chlorophillins (salt of chlorophyll) that are intensely green in colour. That is why some time cooking soda is added when boiling green vegetable because it neutralizes the acid and improves the colour.
– In acidic medium it decomposes with the loss of magnesium from the molecule and the resulting compounds are phaeophytines that are yellow to brown in colour. That is why the colour of green vegetable changes to olive green in the presence of acids.
– All green vegetables contain certain amount of acid in them. When green vegetables are boiled for long time, the cell structure gets destroyed and the acid of the cell comes in contact with chlorophyll and change its colour to olive green. While boiling green vegetables, the lid of the pan should be open so that acid may evaporate and colour could be preserved.
This pigment is responsible for yellow and orange colours in the vegetables. It is not much effected by alkaline or acidic medium. If the vegetables are cooked for long time, it may dull the colour. Vegetables containing these vegetables should be cooked for short time. Carotene pigment is fat soluble. Few examples of carotenoids are:
– Lutein – egg yolk
– Lycopene – tomatoes, watermelon)
– Zeaxanthin – corn
– Capsanthin – red pepper
it is the pigment responsible for white colour in vegetables. Examples: Onion, cucumber, potato, cauliflower.
– In acid medium the colour of pigment becomes brighter. Addition of lime, juice or vinegar will keep them white.
– Basic medium turn this pigment yellow in colour. Overcooking also turn these vegetables yellowish.
This pigment is present in vegetables with red to blue colour. Vegetables like red cabbage, beets, aubergin, contain this pigment.
– In acid medium pigment changes to red. The red pigment is easily dissolved in water.
– An alkaline medium turn this pigment to blue colour.
– Cooking in excess amount and high temperature of water bleaches the colour out of vegetable.
|Pigment||Examples||Colour in Acidic
|Colour in Basic meddium|
|Anthocyanin||Red cabbage,Beets,Aubergin||Red||Blue to Green|
|Chlorophy||||Spinach,Beans,Capsicum||Olive green||Bright green|
Effect of Heat on Vegetables
When heat is applied to the food, it changes its texture, appearance, colour and flavor. In order to cook the food and to make it safe and palatable, heat is applied. This heat
[5:11 PM, 6/1/2017] Mukesh Pal: breaks the complex food structure to simple digestible food particles. We will discuss in brief the effect of heat on various nutrients.
Starches and sugars are both carbohydrates. Both compounds are present in foods in many forms. They are found in fruits, vegetables, grains, beans, and nuts. Meats and fish also contain a small amount of carbohydrate.
– Caramelization means the browning of sugars. The examples of caramelizations are: the browning of sautéed vegetables and the golden color of bread crust.
– The condition when starches absorb water and swell is known as Gelatinization. Celatinization is used in the thickening of sauces and in the production of breads and pastries.
Fiber is a complex substance that gives structure and firmness to plants. This fiber cannot be digested. Sugar makes fiber firmer. Fruit cooked with sugar keeps its shape better than fruit cooked without sugar. Baking soda makes fiber softer. Vegetables When cooked with baking soda become mushy and lose vitamins.
|Starch grains absorb liquid and become soft and swell. When volume increases,the cellulose framework burst and releases the starch that thickens the liquid,||Sugar dissolves more rapidly in hot water then in cold. On further heating it become syrup. At around 275ºF it caramelizes and on further heating, it tums to carbon and ash.||cellulose in not affected by heat.|
|Starch grains become creamy white in colour. On further dry heating it become brown. Water is given off during heating and the starch on the surface is converted to dextrin (sugar)||Dry heat quickly caramelizes the sugar and later on it burn to carbon.|
Protein is a major component of meats, poultry, fish, eggs, milk, and milk products. it is present in smaller amounts in nuts, beans, and grains.
When heat is applied to proteins they become firm and on further heating they start to coagulate. When the heat is increased, proteins start shrinking. At very high heat protein become tough and dry.
Acids, such as lemon juice, vinegar, and tomato products, do two things to proteins: They speed coagulation and help dissolve some connective tissues.
Fats can be either solid or liquid at room temperature. Liquid fats are called oils. The melting point of solid fats varies.
When fats are heated, they begin to break down. When hot enough, they deteriorate rapidly and begin to smoke. The temperature at which this happens is called the smoke point, and it varies by type of fat. A stable fat-one with a high smoke pointis an important consideration in deep-fat frying.
Vit-A & Vit-D: These vitamins are insoluble in water. These vitamins does not lost during moist methods of cooking, that means boiled vegetables have the same amount of these vitamins as the raw vegetables have.
Vit-B1 (Thiamine): This vitamin is highly soluble in water. 50% of the vitamin gets destroyed in cooking liquid. High temperature also destroys this vitamin (pressure cooking). Baking powder destroys this vitamin.
Vit-B2 (Riboflavin): It is soluble in water and lost during normal and pressure cooking
Vit-C (Nicotinic Acid): It is highly soluble in water; it is even lost during normal washing also. It is destroyed during normal cooking. Vegetables containing Vit-C should not be soaked in water. These vegetables should be cooked in small batches as quickly as possible. Vit-C oxidizes and forms a useless substance, to minimize the oxidation these vegetables should be cooked with a lid on. Food containing this vitamin should be stored for short period and must be used as fresh as possible.
Minerals are not affected by heat.
Pictures of Vegetables
Fruit is a ripened ovary of a flowering plant. One of the basic properties of the fruit is: it should be juicy and flashy. Fruits have different tastes but broadly fruits are sweet. Many fruits are classified under vegetable category also. Fruits are storage bank for the seeds. Fruits preserve the seeds.
Fruits are the rich source of vitamins and minerals. They also have a good amount of anti-oxidants.
Classification of fruits
Fruits are classified on the basis of Texture, Flavour and Appearance. Mainly we can classify them into the following categories:
1. Stone Fruits: This category has the fruits that appear hard. Examples: Apples, Pears, Peaches, etc.
2. Soft Fruits or Flashy Fruits: Fruits with soft texture and lots of flash around the seed falls under this category. These fruits are further sub-categorized into following:
– Drupe: These fruits are developed from single flower and are single flashy fruits with single seed. Examples: Plum, Cherry, etc.
– Berry: These are also developed from single flower and with more than one seed. Examples: Papaya, Tomato, Banana, etc.
3. Dry Fruits: These are the fruits with hard texture. These fruits contain lots of oil in them and can be preserved for many days. Examples: Cashew nuts, Almonds, Wall nuts, etc.
Uses of Fruits
Fruits are rich source of nutrients and fibers. Fruits are used in various forms and ways in the cookery.
– As Salads
– As Appetizer
– As snack
– As main course
– As Desserts