What can and can’t go in a microwave

Microwave oven – one of the indispensable assistants in the modern kitchen. Its use dramatically facilitates the life of both an active and lazy hostess. However, for the cooking process to bring benefits and pleasure – you need to understand what can and cannot be heated in the microwave.

So that you do not doubt, here are some helpful lists of suitable and unsuitable for heating in the microwave products, dishes, and other things.


Safety and advantages of heating food in the microwave

Around the microwave still hovering myths about its danger to human health and the risks of cooked and heated food in it.


Afraid to heat food in the microwave? In vain. Microwave oven is safe for humans provided it is serviceable and properly operated.

WHO has long concluded the safety for humans of food cooked in a microwave oven.

Microwave radiation acts only during the operation of the furnace and only inside. At the moment of its shutdown and opening of the door, the magnetron that emits waves is instantly turned off. Therefore, the harmful effects of electromagnetic waves on humans are excluded.


Here they are: heating food in the microwave has its advantages. 

  1. Food is heated quickly, so time is saved.
  2. You do not need to use excess fat, as in heating food in a frying pan, so the food is less calorie-high.
  3. Due to a short stay in the oven, more vitamins are stored in vegetables and fruits.


Features of heating in a microwave oven

The microwave heats up due to the effect on water molecules. The amount of water in the products determines the rate of their heating. Therefore, the heating of products and liquids occurs point and unevenly.

Warming up a bun with sausage, ketchup, and cucumber, we can get hot ketchup, sausage,d a slightly warm bun at the output. It is necessary to keep this in mind so as not to get burned while eating.

Because of the same spot heating, it is necessary to mix drinks from the microwave before use. So you will save yourself and especially children from burns of the mouth and esophagus.

If the dish consists of different ingredients, it is better to stir the components in the healing process, or at least after. This will ensure a more uniform heating and comfortable meals.



The whole process of working with the microwave largely depends on the choice of a plate that can be heated in it along with food. Not every bowl, saucer can be used when heated. Much depends on the material from which they are made and the shape of the dishes themself. 

In deep, cone-shaped plates, the heating process takes much longer than in a container with a flat bottom.

What kitchen utensils can and cannot be used, we will consider in the lists below.

What can not be heated and cooked?

So, it is categorically impossible to heat dishes made of such materials in the microwave.



Can I heat metal dishes? No: any kitchen utensils that contain iron are dangerous for the operation of the microwave oven and its user. 

Metal objects conduct electricity and do not succumb to microwaves in the right way. Microwave waves are beaten off the walls of the metal, which disables the operation of the furnace. In a thin layer of iron, there are alternating currents of high frequency. When exposed to their microwave at least sparkling, as a maximum – there will be an explosion and a shorting. 

Accidentally forgotten iron plate and spoon in it can cause not only equipment breakdown but also the cause of injury to a person who is next to the microwave oven. 

Do not forget that the foil also has a metal base – aluminum. So molds from it are also dangerous for the microwave oven. Even if you stick a small ball of foil into it, you can see and hear all its creaks, sparks. 

You can bake in a microwave oven on a special foil paper, but not in foil. A similar reaction can be seen on any enameled dishes, plates with gilding, any metal finish, stainless steel.



This is a particular type of glass containing alloys of tin and silver. In its composition, some metals are dangerous and harmful, both for the oven and for food. Crystal dishes, at least, will burst due to uneven and rapid heating – or cause sparks, like a piece of foil.

Disposable tableware

In most cases, in disposable dishes, it is not recommended to heat food. It consists of plastic, which, when heated, can melt, catch fire. Not to mention harmful substances. Disposable plates, bowls are designed for little warm and cold foods that take with them to nature, picnics, but not for warming up food. The same applies to plastic utensils. 

Using disposable vessels containing polypropylene is possible, as it is considered harmless to food and humans. 

It is impossible to cook food in them, but it is possible to heat food without alcohol impurities. 


Wooden tableware

Due to the presence of moisture in the composition of the tree, all wooden utensils have a porous and loose structure. 

The material is susceptible to the effects of high temperatures. The tree slowly begins to dry out, char, can spontaneously ignite, deform. It is forbidden to cook food in such dishes, but short heating of products is possible.


What can I warm up and cook?

Consider now the list of dishes allowed for heating in the microwave.

Opal glass, glassware

Dishes made of opal glass are considered best for cooking in the oven and the microwave. Such words look not only exquisite but also have good resistance to high temperatures. 

It is possible to heat glass in the microwave, but with caution. Thinner utensils, for example, a glass jar – high temperatures and a long time in the microwave oven may not tolerate and just burst. But if you heat water in it quickly, the water will become warm. Glass jars and glasses are used to heat liquids.


Ceramics, faience, porcelain

Pottery is considered one of the most heat-resistant since it can be burned at high temperatures when it is created. 

But the use of such plates and bowls in microwaves is a controversial issue. It is recommended to use ceramic and porcelain dishes without gilding or other metal patterns and no chips. You do not need to cover with a lid.


Food film, cellophane bags

Can I use food film and bags in the microwave? Yes, but under certain conditions. Food can not be cooked in them, but you can warm up, covering with a film or a package, after making a couple of thin holes with a toothpick to avoid splashes from food.


Parchment paper, cardboard, foam

If you put to paper or cardboard (for food) in the microwave, it is essential to control the products.  

Fatty and fat-containing products are undesirable to warm up so for safety. Flowing fats when exposed to microwave rays can deform the paper and change the product’s taste properties.

In cardboard glasses, you can not heat liquids in the microwave and foam; on the contrary, you can.


Silicone molds

Silicone molds are very hardy – and are suitable for baking and heating food.

They withstand high temperatures (up to +230 °C) and low temperatures (from -60 °C). It is necessary first to remove excess moisture from silicone molds when used in a microwave oven, and only after that fill with the desired product and cook the dish.


Fabric, towel

Rarely when a towel is used in the oven. Most often, this happens if you need to make dry bread soft in the microwave.  

Without metalized threads, a bun or loaf lies down and goes to the microwave on a clean cotton cloth for a few minutes.


Molds and containers marked for microwave

The sign of the microwave is usually placed on plastic products: 

  • lunch boxes;
  • food storage containers;
  • children’s tableware;
  • baby bottles. 

The warm-up time in such products is no more than 5 minutes; you can not cook in them. Marking can be seen at the bottom of the container, less often on the barcode. Microwave oven for heating food corresponds to the number 5 in a triangle.

Before you start cooking in a particular dish, you should conduct a small test: pour water into a glass or mug, put it on the plate of interest, and place it in the oven for 1 minute. 

If the liquid in the mug (glass) is heated and the plate is cold, this dish can be used in the microwave. Otherwise, when the container is hotter than water – it is better not to use such utensils.


What not to cook in the microwave

In addition to restrictions in the operation of dishes, certain products categorically can not be heated in the microwave. 

In some products of plant and animal origin, under the influence of microwaves, a high amount of carcinogens occurs. In addition, the molecular composition of vitamins, fats, and proteins changes, which is very harmful to health in general.

The food list is small, but it is necessary to know it to avoid negative consequences.


Cooking raw eggs in microwave ovens is strictly prohibited. This is because the influence of microwaves on them, in general, is powerful. In addition, the accumulating steam inside creates the effect of a pressure cooker. Because of this, the egg can explode. 

A similar reaction occurs when heated with eggs boiled in the shell and whole without it. Even making warm scrambled eggs is pretty “dirty.” The yolk explodes, flying all over the microwave. 

The only way to warm up an egg is to cut it into pieces and heat it as part of a dish. You can also warm the omelet, but not more than 2 minutes.


Unrefined oils

They are oxidized and converted into carcinogens.


Greens (spinach, parsley, celery, sorrel) contain nitrates, which turn when heated into toxic nitrosamine compounds harmful to health.


Root vegetables

Whole potatoes or other root vegetables (beets, carrots, etc.) are dangerous to cook in the microwave. 

It is necessary to make notches on them so that the heat eschews out. Otherwise, whole root vegetables can explode inside the microwave. 

It is worth remembering that when re-heating these vegetables, isomers harmful to health are formed. This is a fact. But this does not prohibit heating soups, borscht with the content of these products. 



Getting raisins using a microwave is a wild and crazy thought. Grapes are one of the few berries that can catch fire and explode from the effects of microwaves on them. Tiny sparks can damage the microwave, causing its explosion, fire.



One of the most miniature “harmful” vegetables for the microwave. With corn, you can carry out various manipulations in the microwave (with canned, boiled, baked, popcorn) only with one requirement – it must be covered with at least a food film, as a maximum – a lid from splashes for microwaves. Corn grains very cleverly “shoot” throughout the furnace, thereby making a mess and dirt.


Diet drinks

Sugar substitute turns into poisonous formaldehyde for humans—possible poisoning.


Products in a dense shell or peel

When heated, sausages, tomatoes, liver, etc., begin to expand, stretch the shell and explode. To prevent this from happening, you need to pierce the product with a fork in several places or cut. Then extra steam will come out through the holes, and the food will remain intact. Food will be spoiled, and washing of the stove is guaranteed.


Canned food, stew

This food can not be heated in a native tin or metal jar. Metal, as mentioned earlier, provokes sparks, the explosion of the microwave. 

Shifting to a convenient, for example, clay bowl, the stew is heated for no more than 2-3 minutes. At high temperatures and a long time in the microwave, the fats in the hash begin to “shoot” in all directions. Canned food can not be heated. They contain unrefined oils.


Freeze-animated products

If you heat or heat such products without water, they will remain inedible and burn.



It is better not to use the microwave to melt candied honey but to use a water bath to melt candied honey. Due to the rapid heating, love begins to “fly out” of the vessel on the pallet of the furnace. As a result, valuable properties are reduced: enzymes evaporate, hydroxymethylfurfural is formed.


Water and other liquids

Even when overheating above the boiling point, the liquid in the microwave does not always bubble, as in a kettle on the stove. 

But when you try to pick it up, it can suddenly boil and splash out on your hands, in your face. This happens when you immediately pour superheated water into another container or put a tea bag or spoon in a glass. Severe burns are possible.

To avoid trouble, do not heat each cup for longer than 2 minutes. Then, after turning off the stove, let the dishes with the liquid stand for 30-60 seconds before pulling.

Can I boil water in the microwave? It’s easy. Very quickly, you can boil water for the same tea or infant formula. The main thing is that the mug or glass is open from above.

Tea, coffee, compotes can also be quickly heated in a microwave oven, listening to the stated recommendations.

When heating or boiling liquid in the microwave, it is also recommended to place a wooden spoon or skewer or tea bag in a glass (only without a paper clip!).


Breast milk

Uneven heating with the presence of hot spots can lead to burns of the mouth and esophagus. Also, hot spots can partially kill beneficial bacteria.

If you have warmed up the milk in the microwave, be sure to mix it well and check the temperature before giving it to the baby.

It is better to heat breast milk, not in the microwave but a water bath. 

It should not be subjected to thermal heat treatment at all.


Infant formula and puree

It is worth remembering heating mixtures in the oven, like breast milk – this food becomes toxic. Mix thoroughly and check the temperature of the puree before serving to the baby. 


Milk and fermented milk products

Under the influence of microwave waves, all fermented milk products lose their healing properties: part of the bifidobacteria in it dies due to such heat treatment. In addition, if you eat yogurt, fermented baked milk, cottage cheese, or kefir, they can “curdle” and change their taste after heating. 

It is recommended to get fermented milk products from the refrigerator and leave them to heat up at room temperature for further use or drinking by the child. Milk is recommended to be heated in the microwave only in an open dish. 

Rolls, sushi

Sometimes, the dishes of the favorite Japanese cuisine remain malnourished and go to the refrigerator. Can they be microwaved the next day? In most cases, no, you can’t. First, the rice in their composition will become overdried and can “shoot” inside the microwave. Secondly, rolls and sushi are food that is eaten cold. The exception is baked rolls; they are heated for no more than 2 minutes.

Salt, sugar

Heating salt in a furnace is one of the biggest mistakes. It is important to remember that you can not heat dry objects (salt, sugar, paper bag). They provoke spontaneous combustion, and subsequently, an explosion. It is better to heat it in a frying pan old-fashioned and transfer it to a sock or bag. Salt for warming up in a bag can be both cooking and sea.

Choco Pie

When the cookies are heated, the volume of marshmallows increases, but the product’s shape does not change. 

It is essential to know that when warming up, you need to remove the foil wrapper, put the sweets on a plate, and put a glass or mug of water next to them in the microwave for 4-7 seconds. 

Otherwise, the furnace works like an empty chamber, which is very dangerous.

Non-standard use of microwave oven

Here are examples of exciting operations of a microwave oven, often necessary and helpful in everyday life. 

 The ability to warm up well and quickly in some situations is for the future.

  1. Earth, sand. Warming up these loose seedlings is sometimes very detailed and harmful, and with the help of a microwave oven, the process is accelerated. The earth and sand warm up well, dry out. At the same time, the soil is disinfected.
  2. Coals for hookah. With the help of a microwave, this is also possible: to ignite coals for a hookah. The main thing is to be careful and attentive. After laying them out on heat-resistant dishes, turn on the oven for 10 seconds, if necessary, then for another 5. The main thing is to observe that they do not catch fire. Then pull the tongs out of the bowl and place them in the hookah.
  3. Insulating tape and tape. If they have lost their stickiness, warm them up for 30 seconds. 

Basic recommendations for the use of a microwave oven

  1. Follow the instructions and rules for the safe operation of the device.
  2. Do not use dishes made of metal and with metal inserts, finishing to avoid sparking and ignition of the furnace elements.
  3. Do not turn on an empty microwave oven so that the magnetron does not break; always leave a glass of water in the oven to avoid the situation.
  4. Do not heat food and drinks in an airtight container: when heated, they can explode.
  5. Do not heat food in polyethylene: when heated, harmful substances can get into food.

Follow these recommendations, use the microwave correctly – and it will be an indispensable assistant in the kitchen (and not only), saving you time and nerves in many situations.

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