COOKING METHODS

INTRODUCTION TO COOKING METHODS

There are three methods of cooking:

  • Conduction,
  • Convection and
  • Radiation

Conduction is a method in which the heat is passed from the objects directly,

Convection is a method in which, the gases and any liquid is heated with the help of object,

Radiation is the transfer of energy with the help of electromagnetic waves.

Definition of Conduction

Conduction can be understood as the process, which enables direct transfer of heat through the matter, due to the difference in temperature, between adjacent parts of the object. It happens when the temperature of the molecules present in a substance increase, resulting in vigorous vibration. The molecules collide with surrounding molecules, making them vibrate too, resulting in the transportation of thermal energy to neighbouring part of the object.

In simple terms, whenever two objects are in direct contact with one another, there will be a transfer of heat from the hotter object to the colder one, which is due to conduction. Further, the objects which permit heat to travel easily through them are called conductors.

Definition of Convection

In science, Convection implies the form of heat transfer, by real movement of matter, that occurs only in fluids. Fluid alludes to any substance, whose molecules move freely from one place to another, such as liquid and gases. It happens naturally or even forcefully.

Gravity has a great role to play in natural convection such that when the substance is heated from below, leads to the expansion of the hotter part. Due to buoyancy, the hotter substance rises as it is less dense and the colder substance replaces it by sinking at the bottom, due to high density, which when gets hot moves upward, and the process continues. In convection, on heating up the substance, it’s molecules disperse and moves apart.

When the convection is performed forcefully, the substance is compelled to move upwards by any physical means such as the pump. E.g. Air heating system.

Definition of Radiation

The heat transfer mechanism in which no medium is required is called radiation. It refers to the movement of heat in waves, as it does not need molecules to travel through. The object need not be in direct contact with one another to transmit heat. Whenever you feel heat without actually touching the object, it is because of radiation. Moreover, colour, surface orientation, etc. are some of the surface properties on which radiation depends greatly.

In this process, the energy is transmitted through electromagnetic waves called as radiant energy. Hot objects generally emit thermal energy to cooler surroundings. Radiant energy is capable of travelling in the vacuum from its source to the cooler surroundings. The best example of radiation is solar energy that we get from the sun, even though, it is miles aways from us.

Key Differences Between Conduction, Convection and Radiation

The substantial differences between conduction, convection and radiation are explained as under:

  1. Conduction is a process in which heat is transported between parts of a continuum, through direct physical contact. Convection is the principle, wherein heat is transmitted by currents in a fluid, i.e. liquid or gas. Radiation is the heat transfer mechanism, in which the transition takes place through electromagnetic waves.
  2. Conduction shows, how heat is transferred between objects in direct contact, but Convection reflects how heat travels through liquids and gases. As against this, radiation indicates how heat travels through places having no molecules.
  3. Conduction takes place as a result of the difference in temperature, i.e. heat streams from high-temperature area to low temperature area. Convection happens due to the variation in density, such that the heat moves from low-density region to high-density region. On the contrary, all object release heat, having a temperature more than 0 K.
  4. Conduction usually occurs in solids, through molecular collision. Convection occurs in fluids by mass motion of molecules in the same direction. In contrast, Radiation takes place through the vacuum of space and does not heat up the intervening medium.
  5. The transfer of heat is through heated solid substance, in conduction, whereas in convection the heat energy is transmitted by way of intermediate medium. Unlike, radiation uses electromagnetic waves to transfer heat.
  6. The speed of conduction and convection is slower than radiation.
  7. Conduction and convection do not follow the law of reflection and refraction, whereas, radiation obeys the s

CLASSIFICATION OF COOKING METHODS

MOIST METHODS/WET METHODS

BOILING

Boiling is fast and easy to control, it is done at 100 0C. The secret is to use as little water as possible and avoid overcooking so all the vitamins and flavour are retained. For vegetables such as broccoli, cut into equal-sized pieces. Add to a pan of boiling water, quickly bring back to the boil, cover, and then simmer until the vegetables are just tender. To evenly cook potatoes and other starchy roots, such as parsnips (The parsnip is a root vegetable closely related to carrot and parsley; all belong to the family Apiaceae. It is a biennial plant usually grown as an annual. Its long, tuberous root has cream-colored skin and flesh, and, left in the ground to mature; it becomes sweeter in flavor after winter frosts). and carrots, place in cold water and boil them gently to allow the heat to diffuse through the vegetables.

ADVANTAGES

  • It is the simplest method.
  • It does not require special skill and equipment.
  • Protein soluble starch can be removed and grain is separated.
  • Protein gets denatured, starch gets gelatinized and collagens get hydrolyzed.
  • Uniform cooking can be done.

DISADVANTAGE

  • Loss of nutrients- if excess water is used in cooking and water Is discarded, 30-70% of nutrients like vitamin C may be lost.
  • Loss of colour- water soluble pigments like betanins from beetroot may be lost.
  • Loss of flavours and texture- boiled food are can not considered tasty because flavour compound are leaches into water.
  • Time consuming- boiling may take time and fuel may get wasted.

SIMMERING

When, food is cooked in a well fitting lid at temperature just below the boiling point. The temperature of liquid is 82-90 degree C in which they are immersed the process is known as simmering. It is useful method when foods have to cook for a long time.

ADVANTAGE

  • Food gets cooked thoroughly.
  • Scorching or burning is prevented.
  • A loss due to simmering is minimum

DISADVANTAGE

  • There is loss of heat sensitive nutrients due to long period of cooking.
  • Takes more time and more fuel are required.

POACHING

This requires cooking in minimum amount of liquid at temperature of 93-95 degree C that is below the boiling point. Foods generally poached are egg, fish and fruits. For poaching eggs, the addition of little salt or vinegar to cooking liquid lowers the temperature of coagulation. Eggs get cooked quickly by the process.

ADVANTAGES

  • Very quick method of cooking.
  • Easily digestible since no fat no used.

 DISADVANTAGES

  • It is bland in taste
  • Water soluble nutrients may be leached into water.

STEWING

This is gentle method of cooking in a pan with a tight fitting lid, using small quantities of liquid to cover only half of food. The food above the liquid is cooked by steam generated within the pan. The liquid is brought to a boiling point and then the heat applied is reduced maintain the cooking at simmering temp i.e. 98 degree C. Stewing is slow method of cooking taking from 2-4 hrs depending upon the nature and volume of food being stewed. This method is generally used for cooking cheaper cuts of meat along with some root vegetable and legumes all put in the same cooking pot and cooked in stock or water. The larger cooking time and lower temperature enables tougher meat fibre to become soft. The cooking of meat and vegetables together to make the dish attractive and nutritious since no liquid is discarded.

ADVANTAGE

  • Loss of nutrients by leaching does not takes place.
  • Flavour is retained. Ex- In making oondhya vegetables are stewed by which flavour is retained.

STEAMING

Steaming vegetables is the best way of retaining flavour, colour and vital nutrients. Just be careful not to overcook them as this will make them limp and tasteless. There are two ways to steam vegetables: either place them loosely in a steamer and cover, or to steam them in their own juices, wrap in baking parchment or foil then cook in the oven at 180°C, gas mark 4 for 20 minutes until tender. This last technique is ideal for delicate produce, such as asparagus and baby vegetables. The water should be boiled before the food is placed in steamer. Here the food gets cooked at 100 degree C.

Types of steaming are:

  • WET STEAMING– Here the food is in direct contact with the steams.
  • DRY STEAMING– Here double broiler is used for cooking the food in a container over hot or boiling water. This process is used for such preparation as sauces and custards.

PRESSURE COOKING

A relative small increase in temperature can drastically reduced cooking time and this fact is utilized in pressure cookers. In this the escaping steam is trapped and kept under pressure so that the temperature of boiling water and steam can be raised above 100 degree C and reduced cooking time.

ADVANTAGES

  • It takes less time to cook.
  • Different items may be cooked at same time.
  • Fuel is saved.
  • Requires less attention.
  • Nutrients or flavor losses may be less.
  • Food is cooked thoroughly by this method.
  • There is an indication for completion of cooking.
  • There are less chances of scorching or burning.

DISADVANTAGES

  • Though knowledge of using the equipment is required, otherwise accidents can happen.
  • There may be mixing of flavors.
  • Food may be undesirably soft. Ex- of food cooked in pressure cookers are rice, dhal, vegetables, meats, etc.

BRAISING

It is a combined method of roasting and stewing.

Braising and stewing are techniques that, once you master, you’ll want to use over and over again. They involve cooking ingredients slowly in flavorful liquid on a low heat, usually over several hours, and they guarantee soft, tender vegetables and meats. Once the prep is done, you can put it on the stove (or in the oven) and leave it until it’s ready to eat. This method works best for sturdy and tough vegetables, like winter squash, root vegetables, and beans and legumes, or fibrous veggies like celery, fennel, and leeks. To add even more flavor to your vegetable dish (and to do a true braise), start by sautéing the ingredients in olive oil until lightly browned and caramelized, then add the liquids

BLANCHING

Blanching is a technique used to soften vegetables, either to remove their raw edge before adding to salads or to loosen skins on foods such as tomatoes or shallots. Vegetables should also be blanched before they are frozen, as this destroys the enzymes that cause deterioration. Just add vegetables to a pan of boiling water, return to the boil and cook for one minute. Then plunge the vegetables into iced water to stop the cooking process. Drain and pat dry with kitchen paper before using or freezing.

ADVANTAGES

  • Peels can be removed easily.
  • It is preliminary method for canning and freezing.
  • Microorganisms present on surfaces are partially removed.
  • Enzymes bringing spoilage can be inactivated. 5. Blanching causes better exposures of pigments hence improves the color of food products.

DISADVANTAGES

  • Part of water soluble nutrients may be lost.
  • Long time blanching undesirably softens the food.

DRY HEAT METHODS

BROILING

It is a method in which the food is kept in a chamber and cooked in its own juices with dry heat. it is cooked at 180 0C -200 0C. The source of heat may be above or below. Shirred eggs (oeuf sur la plat) is an example of broiled eggs.

BAKING

Baking is a go-to cooking method for a good reason — the warm air that circulates during the baking process cooks foods evenly all the way through, so you run less risk of ending up with one piece of food that’s crunchy and nearly raw, and another that’s mushy and overcooked. Baking is very similar to roasting, but foods don’t necessarily need to be caramelized, so less oil or other fats can be used (making this a healthy choice if you’re baking vegetables on their own). A slightly less healthy — but still delicious — option is to bake vegetables in a pie crust, piece of puff pastry, or other pastry to add contrasting textures and flavors to your meal, and to create an elegant presentation. One thing to note: some moist vegetables (such as tomatoes) can make pastry crust soggy. To prevent this problem, partially bake, or blind bake, the crust before adding a moist vegetable mixture or filling.

ADVANTAGES

  • Flavor and textures are improved.
  • Variety of dishes can be made.
  • Uniform and bulk cooking can be achieved. Ex- bun and bread.

DISADVANTAGES

  • Special equipment and skills are required.

FATS AS A MEDIUM OF COOKING

FRYING

It is a method in which the food is cooked in fat or oils, that is heated till smoke point. The frying temperature varies from 160 -195 0 It is divided into 3 types:

  • SAUTÉ/ STIR-FRYING

A simple, nearly foolproof method, sautéing is a delicious way to cook almost any vegetable. It’s great for greens, which will wilt and become tender in no time, or for other soft or delicate veggies, like asparagus, peas or snow peas, mushrooms, peppers, summer squash, and onions. Sautéing is also good for those trying to stick to a healthy eating plan — it requires only a small amount of oil or fat, and it’s easy to use healthier options like olive oil, which adds rich, fruity flavor to any vegetable dish. To sauté, start by cutting your vegetables into equally sized pieces so they cook evenly in the pan. Heat a pan over medium- high heat and film with oil. When the oil begins to shimmer, add your vegetables and cook until they reach desired tenderness, stirring them occasionally around the pan during cooking. Stir-frying uses very little oil and cooks vegetables quickly, so they keep their texture and taste. Cut the vegetables into small, even-sized pieces, add a little oil to a preheated wok or frying pan and heat until just smoking. Start with the vegetables that need the longest cooking and keep stirring as they cook. Don’t overfill the pan, as they will steam rather than fry – cook in batches instead. If you are adding a sauce, do so at the very end, then toss to coat and serve immediately.

  • SHALLOW FAT FRYING

Here the food is cooked in fat or oil but not enough to cover it. Heat is transferred to the food partially by conduction by contact with the heated pan and partially by convection currents of foods. This prevents local burning of the food by keeping away the intense heat of frying pan. Ex- paranthas, chapattis, fish, cutlets and tikkas. The finished dish will be crispy brown outside, soft and tender inside. The iron content of food increase when iron tavas are used. Non stick coating frying pan can be used.

  • DEEP FAT FRYING

Food is totally immersed in hot oil and cooked by vigorous convection currents and cooking is uniform on all sides of the foods. Cooking can be rapidly completed in deep fat frying because the temperature used is 180- 220 degree C. In most foods, this high temperature results in rapid drying out of surface and the production of a hard crisp surface, brown in color. The absorption of fat by the food increases the calorific value of food. Generally some 10% of oil is absorbed but larger amount of fat is absorbed when oils are used repeatedly. Samosa, papads, chips, pakodas, etc are made by deep fat frying. The

Stir-frying uses very little oil and cooks vegetables quickly, so they keep their texture and taste. Cut the vegetables into small, even-sized pieces, add a little oil to a preheated wok or frying pan and heat until just smoking. Start with the vegetables that need the longest cooking and keep stirring as they cook. Don’t overfill the pan, as they will steam rather than fry – cook in batches instead. If you are adding a sauce, do so at the very end, then toss to coat and serve immediately

ADVANTAGES

  • A taste is improved, along with the textures.
  • Increase the calorific value.
  • Fastened method of cooking.
  • In shallow frying, the amount of oil consumption can be controlled.

DISADVANTAGES

  • Sometimes the food may become oily and soggy with too much absorption of oil.
  • More attention is required while cooking.
  • The food becomes very expensive.
  • Fried food takes long time to digests.
  • Repeated use of heated oils may produce harmful substances and reduce the smoking point.

ROASTING

Roasting isn’t just for potatoes – root vegetables, squashes and tomatoes all taste wonderful cooked this way. Roasting works by intensifying flavours and causing natural sugars to caramelise, creating a crisp outer coating and a tender centre. For the best results, preheat the oven to 220°C or 450 °F, gas mark 7 and if you’re using root vegetables, preheat the cooking oil for a crisp finish. Cut large vegetables into even-sized chunks and toss in olive oil and fresh herbs, if you wish.

There are many types of roasting:

Pot roasting: cooking is done in a covered pan or pot, only quality meats such as small joints and birds are used. The birds are tied to retain their shapes. The average cooking time is 20 minutes.

  • Oven roasting: this is done in a roasting tray in an oven with the aid of fat and first class meat; poultry and certain vegetables are used. The average time for cooking is 15 minutes per 455 gm (1lb). it is cooked at 450 °F and then reduced to 300 °F. the cooked meat should be removed from the roasting tray and the excess fat poured off. The roasting tray should be placed on the fire and the juices allowed to caramelize and the brown stock added and brought to boil. This brown gravy is called Jus roti and the process is known as de-glaze. 
  • Spit roasting: it is the original form of roasting. It is cooking by direct heat, basted with fat. A spit is constantly revolved to ensure even colouring and cooking. First class quality of small pieces of meat are used and the meat pieces should be juicy (succulent).
  • Poeling: it is similar to pot roasting but the difference is, the item is cooked entirely only in butter. Usually poultry and game are poeled. The poultry is wrapped in thin slices of pork fat, covered with or without buttered paper, placed in a pot and basted with melted butter while it is cooking, covered with a tight fitting lid. Madiera wine or simple red wine with aromatic vegetables are used to give unique flavor to the dish. It is then strained, grease removed and poeling is done in special earthenware utensils and served as the accompanying sauce. Special poeling is known as “Encasserole” and “Encocotte”.
  • Encasserole: the food item is poeled with the butter but without the aromatic vegetables. Brown stock is added separately into the pan and simmered, the extra butter is removed and the poeled pieces is put into the earthen utensils and kept hot in a  bain marie and served in the same utensil.
  • Encocotte: the process is same as Encasserole, except the food item is garnished with vegetables such as mushrooms, the bottoms of artichokes, small onions, carrots, turnips etc, which are turned shaped (tourne) and cooked in butter before being used. 

GRIDDLING/BARBECUING

Griddling and barbecuing are direct heat cooking methods, which produce vegetables with a crisp coating and a tender centre. For the best results, make sure your barbecue or griddle pan is hot before you start. Slice the vegetables so they sit flat in the pan, then brush with a little oil. Avoid pricking them while they are cooking, as this will release their juices and dry them out. To get the char-grilled stripe effect, don’t move them as they cook – just turn them once.

COOKING WITHOUT HEAT/COLD COOKING

PICKLING

Pickling isn’t just for cucumbers! It adds a deliciously pungent, briny flavor to any vegetable you choose to use — though this method works especially well for naturally firm, crisp vegetables that will stand up to the pickling process, and won’t turn to mush. A quick pickle (one that is not vacuum sealed in a canning jar) can last for up to 2 months in the refrigerator and takes only minutes to make. To start, boil your pickling liquid — usually 1 or 2 parts vinegar to one part water — along with your favorite herbs and spices for flavoring. Boil mixture for about five minutes, then pour the hot liquid over prepared vegetables. Allow pickles to cool before refrigerating. To process (in other words, to vacuum seal and preserve) your pickle, first put your vegetables into sterilized canning jars, leaving 1/4 inch of headspace. Pour the hot pickling liquid over them, and then seal the jars. Place jars in a large pot of boiling water (lids should be covered by at least 1 inch of water), and boil for 10 to 15 minutes. Remove jar from water and fully cool on counter-top, without moving, Store in a cool, dark place for up to 1 year.

GERMINATION

Germination is the process by which an organism grows from a seed or similar structure. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm. Sprouts (Sprouted beans) are best example germination.