Friday, October 20, 2017

 

Microwave cooking - An Introduction

 

Microwave oven is a kitchen appliance and had been in existence since early 1970s and was almost universal in the US by late 1980. Currently Chinese firms are the largest maker of microwave ovens in the world. It is now used by most people in the western countries.

Microwave ovens commonly called as microwaves use ‘micro waves' to heat up the food. These waves are absorbed by water, fats or sugars and they are converted directly into atomic motion or heat. Micro waves are not absorbed by most plastics, glass or ceramics but are reflected by metal so never use metal pans or pots to cook or heat your food.

In the conventional ovens the heat is conducted from outside the food towards the centre. But in the microwave ovens, the micro waves are absorbed in the outer layers of food in a manner somewhat similar to other heat from other methods. But microwaves penetrate dry non conductive substances at the surface of many common foods and deposit the initial heat more deeply than other methods. This leads to the common misconception that microwave ovens cook food from ‘inside out'. This depth of penetration of micro waves depends on the composition of food and the frequency, with lower microwave frequencies penetrating better.

Microwave ovens allow user to select different power levels but there is no change in the intensity of micro wave radiation related to the power level selected, but the magnetron which produces the radiation is turned off and on several seconds at a time.

The cooking chamber itself is an enclosure which prevents the micro waves from escaping into the environment. The oven door has usually made of glass for easy viewing but has a layer of mesh of conductive material to shield the micro waves.

Microwaves are commonly available in different types and different sizes.

1) Compact Microwave - These are small and portable and mainly used for reheating food and making small microwave meals. These are not made to cook large amounts of food although suited for light cooking.

2) Medium capacity Microwave - These are larger than the previous one and are standard family sized ovens. They cook slightly faster than a compact oven and can accommodate slightly larger dishes.

3) Large Microwave - These are big and designed for cooking meals. They can handle large dishes and cook all types of food and usually have many auto cook facilities and precise control measures. They are best suited for large families. Some of the large microwaves also have combined grill and convection oven facility.

4) Counter top Microwaves - These are microwaves designed to sit on a table or a counter. They dominate the market.

5) Built in Microwaves - These are microwaves built into the cabinetry similar to the traditional ones. These would normally need a built in exhaust fan installed to remove the hot air.

The microwave power is measured in Watts and this can range between 600 to 1000 Watts. The higher the wattage, the quicker the food will be cooked.

Since heat requires time to diffuse through food and micro waves only penetrate to a limited depth, the food gets heated unevenly in a microwave oven. Mostly uneven heating is partly due to uneven distribution of food and this is remedied by arranging the food so that it absorbs energy evenly, When cooking large quantity of food, stir the food halfway to help reduce any cold spots. Microwaves cook best and most evenly when the hardest and thickest part is arranged in the edges of the container. Leave the food to stand for 2 minutes so that the heat will continue to spread through the food.

Microwave ovens heat food without getting hot themselves unlike the conventional ovens or stoves. The container gets hot due to the conduction of heat from the food within but the container does not get too hot. Therefore care must be taken when the container is removed from the oven although it may not be hot the food inside can be very hot. However there is less risk of accidental burns with microwaves.

Microwaves should not be switched on when empty as the micro waves will bounce off the interior walls and could cause damage. These should be kept clean - do not use any scouring pads or any abrasives. Only use cloth with soapy water.

Use only microwave safe containers, never use any metal containers, tin foil containers or tin foil covers or those with metal rims and even twist ties which have metal in them.

Benefits of microwave cooking:

Microwave cooking is safe, fast, cool, tastier, nutritional, economical and convenient.

1. Safety - Microwave cooking is safe. There is less risk of accidental burns as explained above. These ovens can be positioned at a height best suited to the individual needs.

2. It is important that these ovens are not switched on when empty. It might cause damage to the apparatus.

3. Speed - Microwave cooking time is much less than in conventional stoves and ovens.

4. Taste and Nutritional - All the goodness are preserved and the tastes are retained to a higher degree within the food as nothing is lost during the process of cooking.

5. Economical - These are very economical to use. Their use requires only about one fourth of power than a conventional ovens. Food can be cooked and served in one dish thus reducing washing up costs. Shorter time of cooking means no burnt or overcooked food and thus reducing food waste.

6. Healthy - Only very minimum amount of oil is used in microwave cooking so the cooked food is healthier.

7. Space saving - These are ideal in a kitchen which are small or with restricted space.

8. Cool - Literally microwave cooking is cool as kitchens do not get hot as these ovens produce less heat than a conventional oven or stove. Also there is no smoke or grease associated with this cooking so kitchen is clean.

9. Cleaning - These are easily cleaned since there is no burn on spillages unlike in a conventional oven. The surface and the walls can be easily cleaned with a wet cloth soaked in soapy solution.

10. Convenient - This is a very convenient kitchen aid due to the fact that it is safe to use, economical, space saving and speed with which one can cook.

Disadvantage of microwave cooking:

There is only one disadvantage we can think of is that there will be no crust on the food due to the fact that air in the oven is at room temperature. However this can be remedied by using a microwave with grill.

About cooking containers:

The shapes of cooking containers for cooking curry dishes are an important factor. Since the cooking platform is round and rotates round, ideal container would be a round bottomed one for even heating of the food. Containers should only be filled about half to three fourths full. If the dish is small, food will boil over and spill, on the other hand if they are too big the curry will spread out and edges will dry out. Large round containers are ideal for cooking meat and rice dishes and shallow containers are good for cooking vegetables and cakes.

Even heating can be achieved by arranging the hardest and thickest parts around the edges of the container and by stirring halfway to reduce any cold spots. Also leave the food in the container following cooking to rest for two minutes before serving.

What can be cooked in a microwave oven?

Virtually anything can be cooked except frying in oil, boiling eggs with shell on, heating food or liquids in sealed containers.

When oil is heated, it reaches temperatures that can ignite and cause fire. Eggs when boiled will burst. When food or liquid in sealed containers are heated, the steam inside will get built up and cause excessive pressure causing the container to burst.

We can also recreate some of the Yarlpanam recipes using microwave ovens to some extent and this will give our future generation a chance to taste this wonderful food. In these recipes, you can use readymade curry paste easily available in all super markets instead of roasted curry powder. Like all spice mixtures, you have to select the correct paste and try out with recommended quantity and then adjust measurements according to your taste.

We give you a sample of dishes that can be cooked in a microwave. Please remember that we were not successful to recreate vegetarian dishes in a microwave cooker except boiling them. It was good to reheat them.