Cooking II Unit V II Pokhara University

 

Cooking

Introduction

Cooking is a process of chemical and physical change in food items to become a complete dish in which more than two ingredients or food commodity are combined and processed by application of heat. Cookery is defined as a “Chemical Process”, the mixing of ingredients; the application and withdrawal of heat; decision-making, technical knowledge and manipulative skills. In the more advanced stages a further element occurs- that of creativity. Cookery is considered to be both an art and technology. It gives a variety to the menu, as one-food items could be cooked in various ways and gives different textures. Different methods of coking when used make the menu interesting and enhance variety. It is therefore, easier to plan balanced diet. Cooking also preserves food for a longer time. The high temperature destroys bacteria and limits spoilage.

Aims & Objectives of Cooking

The aim or the intention of cooking is to see that the food is cooked, undergoes a physical change, sometimes a chemical change and is acceptable. During the cooking process, it breaks down the cellulose in plant foods, softens some of the connective tissues of meat, and breaks down gets starches present. The alteration is brought about in texture, thus assisting mastication, by physical and chemical changes.

·   Well presentable, eye appealing

·   Improve taste, flavor and color

·   Give varieties to the dish. E. g. Roasted chicken. Chicken ala Kiev

·   Makes food palatable

·   Assists mastication.

·   Kills harmful bacteria and parasites.

·   Helps in the digestion.

·   Creating an appetite to the palate.

·   Attractive through chemical change.

·   Gives name to dish. E.g. poached egg, backed haddock

Methods of Heat Transfer

The process of cooking requires the transfer of heat energy throughout the food. Basically there are three methods of heat transfer.

1.      Conduction

2.      Convection

3.      Radiation

Conduction

It involves the transfer of heat in solid materials. Some materials retain heat in better than other. Copper heats up very quickly and evenly but does not retain heat very well. Stainless steel, iron, aluminum, ceramic cookware on the other hand retain heat well. Conduction includes shallow frying, sautéing and stir-frying.

Convection

It involves the transfer of heat in liquids and gases. On heating the particles expand, become less dense and rise. The colder particles sink to take their place. This cause convection current; which distribute heat to the food. Convection includes poaching, deep frying, braising.

Radiation

It involves the transfer of heat to the food from a very hot source, which is placed at the distance away from it. These waves pass the heat from heat sources and are absorbed into food. Most radiation of heat is found on the grill, salamander, toaster, microwave oven, electric oven or open barbecue where direct rays of heat pass from the heat sources on to the food and gets cooked