{"id":178,"date":"2019-05-17T09:45:59","date_gmt":"2019-05-17T09:45:59","guid":{"rendered":"http:\/\/hsp06.epgpbooks.inflibnet.ac.in\/?post_type=chapter&p=178"},"modified":"2019-05-17T10:29:30","modified_gmt":"2019-05-17T10:29:30","slug":"microwave-cooking","status":"publish","type":"chapter","link":"https:\/\/ebooks.inflibnet.ac.in\/hsp06\/chapter\/microwave-cooking\/","title":{"rendered":"Microwave Cooking"},"content":{"raw":"
\"epgp<\/a>\r\n<\/span><\/div>\r\n \r\n\r\n \r\n\r\n \r\n\r\n \r\n\r\n \r\n
\r\n\r\n1. OBJECTIVES<\/strong>\r\n\r\n \r\n\r\nAfter learning this session, the readers should able to\r\n\r\n \r\n\r\n1.\u00a0\u00a0\u00a0\u00a0 Describe the functioning and principles of microwaves\r\n\r\n2.\u00a0\u00a0\u00a0\u00a0 Describe how to use the microwave oven for cooking and its safety measures\r\n\r\n \r\n\r\n2.\u00a0 INTRODUCTION<\/strong>\r\n\r\n \r\n

Microwaves are high frequency, non-ionizing electromagnetic waves which are similar to radio and television waves but are shorter. Hence they are known as microwaves. They are not, however, as powerful as infrared rays and do not resemble x-rays, gamma rays and ultra violet rays in any way.<\/p>\r\n \r\n

Inside the microwave oven is a magnetron vacuum tube. This converts ordinary electrical energy into high frequency microwaves. These waves are channelized into oven cavity through a wave guide. A stirrer fan distributes the microwaves evenly.<\/p>\r\n \r\n

Heat Transfer: The radiated energy, in the form of microwaves, affects only some of the molecules in the food. These are the electrically charged molecules of which the most important in food is water.<\/p>\r\n \r\n

1. Microwaves penetrate the food to a depth of 2 to 5 cm.<\/p>\r\n

2.Microwave passes on the energy to water molecules. The water molecules then vibrate (move) 2000 million times per second. This movement produces a band of HEAT inside the food.<\/p>\r\n

3. The heat produced in this area is CONDUCTED (solids) or CONVECTED (liquids) throughout the food.<\/p>\r\n

4. Food is heated from all directions producing very fast cooking.<\/p>\r\n \r\n

Traditional cooking involves loss of heat to the oven, to the equipment and to the kitchen itself. Microwave cookery in comparison with conventional cooking, offers a quick and efficient method of cookery.<\/p>\r\n\r\n<\/div>\r\n

    \r\n \t
  1. EQUIPMENTS: THE MICROWAVE<\/strong><\/li>\r\n<\/ol>\r\n \r\n

    Microwaves are produced from electricity by a magnetron. They are then directed into an oven and distributed evenly by a fan. A shiny oven surface allows the waves to be reflected in all directions to promote fast and even cooking.<\/p>\r\n \r\n

    \"\"<\/p>\r\n2.1. Structure of microwave oven<\/em><\/strong>\r\n\r\n \r\n\r\nMicrowave oven generally consists of the basic components listed below:<\/strong>\r\n\r\n\"\"\r\n

    \u00a0 i) Power Supply and Control <\/em>\u2013 to control the power to be fed to the magnetron<\/p>\r\n

    \u00a0ii) Magnetron <\/em>\u2013 it is the vacuum tube where electrical energy is converted to an electromagnetic field.<\/span><\/p>\r\n

    iii) Waveguide<\/em>\u2013 it is rectangular metal tube to direct the microwave generated from the magnetron to the cooking cavity. It also helps to prevent the direct exposure of the magnetron to any food particles<\/p>\r\n

    iv) Stirrer <\/em>\u2013 commonly used to distribute microwaves from the waveguide to allow more uniform heating of food<\/p>\r\n

    v) Turntable<\/em>\u2013 it rotates the food products through the fixed hot and cold spots inside the cooking cavity and allows the food products to be evenly exposed to microwaves.<\/p>\r\n

    vi) Cooking cavity <\/em>\u2013 space inside where the food is heated when exposed to microwaves<\/p>\r\n

    vii) Door and choke <\/em>\u2013 it allows the entry of food to cooking cavity. They are engineered in such a way that they prevent microwaves from leaking between the door and cooking cavity.<\/span><\/p>\r\n \r\n\r\n2.2. Adaption\u2019s of basic equipment<\/em><\/strong>\r\n

      \r\n \t
    1. Turntable<\/em>: Convection currents are slow to develop and therefore many microwaves are fitted with a turntable to stimulate stirring.<\/li>\r\n \t
    2. Browning attachments<\/em>: Microwave cooking produces no browning of the surface as temperatures inside the oven are not high enough to produce the surface changes.<\/li>\r\n \t
    3. Browning dishes: These are ceramic dishes coated with a layer of material which absorbs microwaves and gets heated. Food placed on the hot surface will seal as if in a hot frying pan<\/li>\r\n \t
    4. Infrared heaters: These are positioned in the oven so that at the end of cooking browning can be achieved quickly.<\/li>\r\n \t
    5. Microwave cookers: These are conventional ovens with the facility to produce microwaves. They combine both systems to produce a high level of versatility speed and cost effectiveness.<\/li>\r\n<\/ol>\r\n

      Temperature probes<\/em>: Because the food may be cooked inside whilst the surface remains cool, traditional eye judgement to determine if food is cooked or not is impossible. Thermometers which will pierce the surface of the food and measure internal temperatures are therefore useful. These are called temperature probes and are available ready-installed in some ovens usually referred to a computerized microwave ovens. They are especially useful in cooking meat and poultry to avoid under cooking and dangers of food poisoning. Example of temperature probe is shown in Figure<\/p>\r\n \r\n\r\n\"\"\r\n\r\n2.3. Cooking dishes<\/em><\/strong>\r\n\r\n \r\n\r\n2.3.1. Size and Shape<\/strong>\r\n