Defra have established that substantially less energy is used when cooking foods in a microwave than when using an energy efficient electric oven or stovetop, but also found that habit and reluctance to cook with a microwave often contribute to people continuing to use ovens [1]. However, microwaves can be used to cook most foods, from vegetables and meat to eggs and even cakes, and food can retain more nutrients, flavours and texture when cooked this way [2]. There are some simple guidelines that make cooking with a microwave simple and convenient, some more obvious than others:
- Cooking times will vary between microwaves according their power and the setting they are on. If microwave cooking times are given on packaging, check what wattage microwave they are for (e.g. 750 W, 800 W, etc) and if the power of your microwave is higher or lower, slightly increase or decrease the cooking time, respectively
- If you are unsure, it is better to cook the food for slightly less time than stated, and check it. Unlike with an oven, the food itself is heated rather than the whole cooking compartment, so cooking can be stopped and the microwave opened to check on it as many times as necessary without losing large amounts of heat
- The setting may need to be adjusted according to food type, but in general medium-high can be used for cooking and low-medium for defrosting
- Liquids such as soup or milk may need to be cooked in increments, with stirring between, to stop them boiling over and to ensure they heat evenly
- Covering liquid food will help keep the microwave cleaner and aid even cooking [3]
- Food with a high water content will need little or no water added to it, whereas other foods such as rice and frozen peas will need more – check cooking instructions where necessary
- Dense foods such as potatoes or corn on the cob will need turning over halfway through cooking to ensure they cook throughout
- Pierce food with membranes or skins, for example eggs, potatoes and sausages, with a fork or knife to allow steam to escape
- Round dishes will give the most even cooking [3]
- Food will tend to cook more quickly at the edge of a dish, so arrange the densest or thickest parts of vegetables or cuts of fish or meat at the edge, with the thinner parts in the centre [3]
- Where possible, cut food into equal sized pieces so that they take the same amount of time to cook [3]
- Foods containing a lot of sugar need to be checked during and after cooking as sugar can burn on the surface of food and reach very high temperature within it
- Food containing a lot of fat, such as sausages or cheese, will cook very quickly but not usually brown. If it is important that meat looks brown when cooked, it can be brushed with gravy, brown coloured sauces or butter/margarine before cooking to achieve this [2, 4]
- Never put anything metallic in a microwave
- Leave food to stand for at least one minute after removal from the microwave, to ensure it has finished cooking – denser foods need a longer standing time [3]
Microwaves can also be used as cooking aids, for example chocolate can be melted in under a minute, citrus fruits will yield more juice if microwaved on high power for 20 seconds before squeezing [5], under ripened avocadoes can be softened enough to eat by microwaving for about one minute, then leaving to cool before peeling [6], bread dough can be quickly proofed and foods such as dried fruit, butter and crystallised honey can be softened by warming for a few seconds in the microwave [7]. Along with general microwave cooking, these methods can save energy compared to melting, cooking or softening food in a pan and can also help reduce waste. There are various products available that are designed specifically for use in microwaves, such as steamers, egg poachers, casserole dishes and chip cookers, as well as websites (e.g. [2, 8, 9]) with microwaving tips and recipe ideas.
[1] efficient-products.defra.gov.uk/spm/download/document/id/786
[2] http://busycooks.about.com/od/microwaveovens/a/microwavemagic.htm
[3] http://www.ctahr.hawaii.edu/new/resources/microwavecooking.pdf
[4] http://www.ehow.com/how_5072411_brown-food-microwave-oven.html
[6] http://www.ehow.com/how_5041118_ripen-avocados-quickly-microwave.html
