Microwave oven technology

The microwave oven is an electronically controlled home appliance used for cooking. It uses the principle of dielectric heating at microwave frequencies. The frequency of microwaves is 2459 MHz.

Microwave heating has several industrial applications such as product drying and large-scale heating and processing, but the main application is in household and commercial cooking.

A microwave oven works because the microwaves pass through the food container and into the food. They can pass easily though most kinds of plastic, paper, glass and any pottery or china without metal trim, paint or glaze.

The microwaves are generated in the cooking cavity. These microwaves are reflected from the walls of the cavity and strike the food. Because of these high frequency waves the heat is induced inside the food. The temperature increases much faster than the conventional cooking.

The heat is conducted inside the food and it is cooked in short time. Although microwaves will generally not damage cooking utensils, it is important to remember that the heat of the food may sometimes do so. For example: syrup heated in a glass utensils would reach such a high temperature that the glass would break.
Microwave oven technology

Griddling

Griddle cooking is performed by using a flat metal pan, sometimes with the addition of oils and butter.

Griddling and panfrying are the major methods of food preparation for breakfast items. About 75-80% of all breakfast menu items are prepared on the griddle or in the fry pan.

Griddling normally give slightly more roasted flavor than with panfrying, which makes griddling is great for seafood.

Some griddles have bars running across them. This enables the meat to be charred or seared, providing a distinctive flavor and color. Too much oil on the griddle can lead to excessive smoke and can hamper the cooking process.
Griddling

What is broiling?

Broiling is the only preparation utilizing direct heat to cook meat. It is the most perfect way of cooking meat and fish. Broiling may be done in a charcoal unit or hibachi in which the heat comes from beneath, or it may take place in an oven or special boiler compartment.

Properly broiled meats have a well-browned, flavorful crust on the outside, and the inside is cooked to be desired doneness and still juicy.

The most delicious results are obtained by broiling steaks, chops, young chickens, squabs etc. directly over the glowing coals.

Charcoal is best for broiling, but hard wood or hard or soft coal may be used, provided it is free from smoke.

Broiling requires tender cuts of meat at least 2.5 cm thickness, with the thickness being uniform throughout the cut to be broiled.

If cuts thinner than this will become unpleasantly dry during broiling. For further best results, only high-quality, tender cuts with a good fat content should be broiled.

Since broiling is done by means of a rather intense, continuous heat, it is important that the entire surface of the meat be at a uniform distance from the heat source.

Broiling is carried out at a temperature of 176 °C until topside is brown. At this stage the meat is proximately half done.

Controlling the flame is very important. If the flame is too high, the outside will scorch before the inside is done and the dripping fat might start a fire.

Broiling time depends not only on the thickness of the meat but also on the intensity of heat put out by the broiler.

If the fat does catch on fire, the resulting soot will make the meat less than desirable to eat.

To add flavor interest to meats to be broiled, the meat can be marinated for at least an hour before broiling. Acid fruit juices in a marinade can also help to promote tenderness.
What is broiling?

Drying of food

Drying food is inexpensive. A commercial dehydrator can easily pay for itself in a summer or two.

This is one of the oldest preservative techniques; the sun, fire, and mounds of host sand have been used of dry foods since prehistory.

For most foods, the drying nutritional value retained is about the same as with freezing. Drying has a lower heat exposure than canning and therefore destroys fewer vitamins.

Drying reduces the water activity, thus preserving foods by avoiding microbial growth and deteriorative chemical reactions.

The effects of heat in microorganisms and the activity of enzymes are also important in the drying of foods. 

While sun drying used to be the most common treatment for prunes, raisins, apricots, and figs, forced hot air-drying is now widely used because it is more predictable.

Home and restaurant cooks can use the oven or small electric driers whose temperature is easier to control.

Drying conditions profoundly influence pasta cooking quality. If pasta dries too quickly the surface will harden and the pasta may fracture due to stress as moisture trapped within attempts to migrate to the surface.
Drying of food

Method of cooking: Boiling

Boiling is cooking in boiling water. Boling is the basic cooking methods. Most of the cases, additional steps are required after the basic cooking is completed in order to make the product ready for serving.

Boling is a moist method of cooking where prepared food is cooked in a liquid which contains water.

The boiling action may be quick and rapid; or slow, with a gentle surface movement known as simmering. Water boils at 212°F and simmers at 185°F.

Water is boiled for two purposes: First, cooking of itself to destroy organic impurities; second, for cooking foods. Boiling will make foods tender, more palatable and digestible.

Boling water toughens and hardens albumen in eggs; toughens fibrin and dissolves tissues in meat; bursts starch-grains and softens cellular in cereals and vegetables. Although fish and shellfish are more desirable to poach, there are some classic dishes which are boiled, for example lobsters are usually cooked by boiling.

In certain cases the product is only partially cooked by boiling or steaming and is finished by another cooking method, such as sautéing or baking.
Method of cooking: Boiling

Frying of food

Frying, especially deep frying has become the most popular food preparation technology during the last five decades.

The frying technology is important to many sectors of the food industry, including suppliers of oils and ingredients, food service operators, food industries and manufacturers of frying equipment.

Fried food is food that has been cooked in a large amount of fat (as in deep frying) or a small amount of fat. 

The fat is absorbed into the surface of the food, and the heat of the changes the character of the food, shrinking it slightly and changing its color.

Shallow frying is a dry heat method of cooking, where prepared food is cooked in a pre-heated pan or metal surface with a small quantity of fat or oil.

Shallow frying is a fast method of cooking because heat is conducted from the hot surface of the cooking pan directly to the food.

Deep frying is a dry heat method of cooking, where prepared food is cooked in preheated fat or oil. It is a very important method of cooking because it is fast, convenient and deep fried foods are generally liked for flavor and texture.

The fats used for frying gradually undergo certain chemical changes during use. The most important changes are:
Color formation
Oxidation
Polymerization
Hydrolysis

The main change in the food composition during frying is the loss of water and its replacement with frying oil. In contact with hot frying oil, water is rapidly covered into steam at least in the surface layer of fried material.
Frying of food