Microwave ovens are a staple of the American kitchen. Over 90 per cent of American kitchens have at least one microwave oven. For years the microwave was primarily used for reheating food and making popcorn, but the microwave oven is fast becoming an indispensable appliance in busy households. In spite of the many advantages offered by microwave cooking, especially the quick cooking time, there are a few disadvantages in depending on microwave ovens for all of your cooking needs.
Microwave Cooking Technology
Microwave ovens cook food using microwaves, which are very short radio waves, created by small magnetron inside the oven. The waves penetrate the food at about 1 to 1½ inches deep and excite the fat and water molecules, vibrating them at a frequency that creates high temperatures.
Microwave cooking heats food unevenly. Because microwaves only penetrate food about 1 to 1½ inches deep, the centre of thicker pieces of food have to cook by the conduction of heat from the outer areas of the food to the inner areas instead of by microwaves, creating hot and cold spots throughout the food. Insufficient heating of many foods creates the ideal environment for pathogens to thrive and cause food-borne illnesses. Using a food thermometer to test in several places will help to ensure that the food has reach high enough temperatures throughout to kill bacteria.
Limited Cooking Options
The air temperature in a microwave oven is equal to room temperature; therefore, the surface of the food stays cooler than it would in a conventional oven, which prevents the food from browning or becoming crispy. Because food cannot be browned or crisped in a microwave, a hob or conventional oven may have to be used in addition to the microwave to achieve certain textures.
Microwaves can safely penetrate most nonmetallic containers to heat food. However, containers and dishes that are not specified for microwave use may cause harmful chemicals to migrate from the container to the food and may warp or melt in the microwave.
Pacemakers -- No Longer a Problem
Microwave ovens in public places used to have signs posted nearby warning about the dangers of getting pacemakers too close to the oven. A leaky oven could interfere with the operation of a pacemaker. However, that potential problem has been addressed. Implanted pacemakers have shielded circuitry and filters that recognise and reject the interference. Additionally, all microwave ovens manufactured in the United States must meet a 1971 FDA regulations that minimises leakage. Many manufacturers have set even more stringent standards to eliminate the hazards of pacemakers near microwave ovens.
- USDA Food Safety Information: Microwave Ovens and Food Safety; 2006
- University of Texas Health Center: Microwave Tidbits; 2007
- U.S. Food and Drug Administration: Microwave Oven Radiation; 2010
- UNSW School of Physics: Superheating and Microwave Ovens
- HealthNewsDigest.com: Microwave Ovens and Pacemakers