Honey, I blew up the Microwave!

Microwave Safe – Part 3: What You Need to Know About the Microwave

In this the final installment of the Microwave-safe series, I want to look at the different kinds of materials used in cooking bowls and dishes that we often put in the microwave.25917939_s


Ceramics are one of the most common materials in the microwave. Many bowls, plates, and mugs are made from ceramics. However, depending on the type of ceramic you use you may be facing disaster. A low fired ceramic dish may soak up moisture in the clay body. If that moisture gets heated enough it could turn to steam and expand and eventually burst, leaving you with a very broken dish and possibly a ruined microwave. A test to see if the ceramic is low fired or not is to carefully tap it and listen to the sound it makes. If you hear a clean ring the piece should be dry, but if there is a very dull sound it is most likely still wet and not worth chancing in the microwave.   Look for words such as, “earthenware” and “stoneware” on the bottom of your dishes or on the box they came in.  This indicates that the ceramics has been fired in such a way that they are dry and microwave safe. [1]


The spinning dish in most microwaves is made out of glass making people assume all glass is microwave safe. But is it? While most glass cookware is microwave safe, always check either the bottom of the dish or the box it came in to verify that the dish is in fact microwave safe. Glass bowls, plates, mugs, and cups that have a gold or silver lining are typically not microwave safe.


Plastics such as Tupperware are very convenient for storing leftovers in the fridge, but can you put them straight in the microwave, or do you need to put them on a plate? Most take-out containers, water bottles, plastic tubs or jars, and plastic containers used for yogurt or mayonnaise are not microwave safe. Some of the substances used in making plastics have been known to leach out into your food when the plastics are heated at a high temperature. Some plastic containers will show the microwave safe icon. The way the FDA determines if a plastic container is microwave-safe or not is by a series of tests that estimates the ratio of plastic surface area to food, how long the container is likely to be in the microwave, how often a person is likely to eat from the container, and how hot the food can be expected to get during microwaving. They then measure the chemicals that leach out and the extent to which they migrate to different kinds of foods. The maximum allowable amount is 100–1,000 times less per pound of body weight than the amount shown to harm laboratory animals over a lifetime of use. Only containers that pass this test can display a microwave-safe icon. [2]

It is noteworthy to say that take-out cases that are microwaveable are made only for a 1-time use and should mention this on the package.  These containers should only be 11970204_sused that one time.



Metal is one of the few materials that have a definite “do not microwave” label. While certain glasses, ceramics, and plastics can be microwaved, no metals, including aluminum foil, can be microwaved. In part 1 (The Bright Side) I explain how the microwave works, what I didn’t explain was that the inside of a microwave is lined with metal and the waves can easily pass through ceramics and glass dishes with little problem, but a metal object can deflect the waves from hitting the food causing the waves to jump around non-sensically which can damage the interior of the oven.

There can be an even bigger problem with the metal container heating up to the point of causing sparks and popping.  If left too long, a fire can start.

We have now explored the benefits of the microwave, common controversies of the microwave, and safe microwave practices. While I do not repair microwaves, I do feel a bit more confident using the one I own now that I have learned a little more about it.

Have you ever experimented with something in the microwave that didn’t end well? Tell us your stories in the comments below!


Gords ApplianceGord Haines is a journeyman appliance technician with over 25 years of experience. Contact Gord’s Appliance for repair and servicing of all your residential appliances.




[1] http://www.ceramicstoday.com/articles/031901b.htm

[2] http://www.health.harvard.edu/fhg/updates/update0706a.shtml

Microwaves: Is there a dark side?


Microwave Safe – Part 2: What You Need to Know About the Microwave!

In Part 1 of the Microwave-safe series, we looked at the positive attributes that the microwave has. However, this small appliance is also riddled with controversy. In this post we will look at some common dissenting opinions regarding the microwave oven.

Food Composition:

One of the controversies surrounding the microwave is that it alters the actual composition of food. The concern is that this alteration produces toxins and carcinogens in your food. There is proof that certain plastics containing BPA’s, when used in the microwave, can leach chemicals into the food.  I turn to Professor Peter McIntyre from the Texas A&M University to tell us in his words about the changes about the microwave makes to food:

“When food is placed in a microwave oven, the electromagnetic fields from the oven induce electric currents within the water in the food. Because all of our food (like ourselves) is mostly water, this tactic is a pretty good way to generate heat uniformly throughout a serving of food. That is also why it is possible to heat food more quickly in a microwave oven than in a conventional oven, where the food must be heated from outside in. Microwaves do nothing more to food than heat it. There is no evidence that microwaves alter the composition of food or have any other detrimental effects.” [1]

Nutritional Value:

Another concern is that microwaving food changes the nutritional value.  Will microwaving my carrots reduce their vitamin content?  A study published in the November 2003 issue of The Journal of the Science of Food and Agriculture found that broccoli cooked in the microwave with a small amount of water lost up to 97 percent of its beneficial antioxidants. By comparison, steamed broccoli lost 11 percent or fewer of its antioxidants.

A Japanese study by Watanabe showed that just 6 minutes of microwave heating turned 30-40 percent of the B12 in milk inactive. This study has been cited by Dr. Andrew Weil as evidence supporting his concerns about the effects of microwaving. Dr. Weil wrote:   “There may be dangers associated with microwaving food… there is a question as to whether microwaving alters protein chemistry in ways that might be harmful.” [2]



It is important to mention that heating in all forms can alter the nutritional content of food. When you cook with water or other liquids some of nutrients in food can escape from the food and into the surrounding liquid.  Regardless as to whether you are boiling your veggies in a pot on the stove, steaming them, or cooking them in the microwave oven, the best way to avoid degrading the nutrients too much is by cutting down cooking time.



Electromagnetic Fields:

There is a concern about the electromagnetic field that is produced by the microwave and its effect on people.  A federal standard limits the amounts of microwaves allowed to leak from an oven in its lifetime to 5 milliwatts per square centimetre at approximately11970204_s 2 inches from the oven’s surface. The limit is set as such because it is far below the threshold known to harm people. The Food and Drug Administration has the responsibility for carrying out an electronic product radiation control program and they enforce the standards of performance for electronic products to ensure the safety of the public. In order to do this the FDA tests microwaves in their own laboratory and evaluates the manufacturers radiation and quality control programs at their sites. Health Canada has the responsibility to carry out the laws and regulations set by the FDA.

Though the FDA believes there is no hazard or harm coming from microwaves they do continue to test and reassess microwaves and their impact. [3]

As varied as our personalities so too are our opinions when it comes to subjects of controversy.  Are you decidedly in one camp or the other?  Is the microwave good for you or is it just convenient? Is it bad for our health? Let me know what you think in the comments below!


Gords ApplianceGord Haines is a journeyman appliance technician with over 25 years of experience. Contact Gord’s Appliance for repair and servicing of all your residential appliances.




[1] http://www.scientificamerican.com/article/is-there-any-evidence-tha/

[2] http://articles.mercola.com/sites/articles/archive/2010/05/18/microwave-hazards.aspx

[3] http://www.fda.gov/radiation-emittingproducts/resourcesforyouradiationemittingproducts/ucm252762.htm














Faster Than a Speeding Bullet!

Microwave Safe – Part 1: What You Need to Know About the Microwave

I want to start off by saying that I do not repair microwaves. However, I do think the subject of microwaves is an interesting one that needs to be reviewed and explored. In this 3-part series, I will cover:  the benefits of the microwave, the disadvantages of the microwave, and safe cooking practices we should all follow. Though I do not repair microwaves, I do use one and found researching this topic to be very interesting.

History of the Microwave:

The 1940’s were an interesting and exciting time in our history. Not only did the Second World War end, the bikini was introduced, and in 1947 the first microwave appeared on the scene.  It was developed by accident by an engineer named Dr. Percy Spencer, who was working on the development of radar in World War 2. Dr. Spencer discovered that radar waves used to detect planes could also heat food. The story goes that the doctor had brought a chocolate bar to work in his pocket and found that it had melted. He deduced that the microwaves he was working with had caused it to melt and after some experimentation he realized that microwaves cooked food quickly.

The first commercial microwave oven was produced in 1954 and was called the 1125917939_s61 Radarange. It was very large, very expensive and had 1600 watts of power. In 1967 the first domestic microwave was introduced. The microwave was very expensive and therefore sales were very slow.  Soon the demand became so great that the price dropped which made it more affordable. [1]

How it works:

Microwave ovens take their name from the use of microwaves to heat food. These waves work by getting absorbed by water, fats, and sugars which are then turned into atomic motion producing heat. Microwaves have a very neat property in the fact that
they are not absorbed by plastics, glass, or ceramics.  Metal reflects microwaves which is why you aren’t supposed to put metallic containers, gold or silver plating or paint in the microwave.

The microwaves excite the water molecules in food and as they get excited it causes friction and that friction is what heats up the food. [2]

On the Run:

The first major benefit is how fast the microwave is. Nowadays, everything is go, go, go! Sometimes the best way to have a hot meal is to heat it up in the microwave. There’s no way to get around the fast pace that life can take, but having a microwave oven to heat up leftovers, or cook a meal can go a long way in helping you out on those days when you just don’t have time to cook. You can easily make eggs for breakfast, soups and chili for lunch, and rice and pasta for supper. The amount of food and meals you can cook is practically endless. For me, this is the major benefit of using a microwave.


Ouch! :

Another benefit to the microwave is that the amount of burns received from using the microwave versus the stove or the oven is substantially lower. Since the heating element is inside the microwave the outside doesn’t get hot and as soon as the machine shuts off the heating element cools.  From time to time I have needed to use oven mitts to take out a hot plate or bowl because the food itself has caused the container it is in to get hot.   Caution is needed when taking out dishes, but burns from the microwave itself are unlikely as once the door opens the heating element stops and cools.

Heats so Good:

A substantial benefit to using the microwave is in the way that it heats up food. Because food is heated by exciting water, fat, and sugar molecules, frying or searing doesn’t occur. The food should heat up from the inside out giving it all-over heat within the food.

Those are some of the many benefits of having a microwave. Did I miss something that you enjoy about your microwave? Comment below to let me know! In part 2 we will be exploring some of the popular controversies of the microwave.

Gords ApplianceGord Haines is a journeyman appliance technician with over 25 years of experience. Contact Gord’s Appliance for repair and servicing of all your residential appliances.




[1] http://www.smecc.org/microwave_oven.htm

[2] http://home.howstuffworks.com/microwave1.htm