A precious ally for those who have little time to cook, the microwave oven is now present in all our kitchens and it is used to cook, but above all to heat already cooked food in a few seconds. The speed with which the microwave oven acts is due to the particular type of waves that "activate" the molecules present in our food, but are we really sure that it is the best cooking method besides being the fastest? How does it really work? Can you really cook everything in the microwave oven or not? Today we reveal tips and secrets of a little great electrical appliance that has changed our way of cooking forever.

1. Microwave oven, how it works

Unlike the classic oven in which heat is fundamentally transmitted by conduction and irradiation, in the microwave oven cooking and heat derive from the effect that the waves have on the water molecules present in food. The molecules, "shaken" by microwaves, begin to move and overheat to reach even very high temperatures that can heat or cook food. This type of cooking saves time: all the heat remains inside the food and nothing is lost. Furthermore, the process we explained to you shows why heating and cooking times decrease when a food contains a large quantity of liquids. On the market we can also find and buy "combined" microwave ovens: this term refers to ovens that have both the microwave functionality and the "classic" cooking function,  for example these are perfect for preparing au gratin dishes.

2. Defrost food in the microwave oven: a myth to debunk

In addition to heating our already cooked food or cooking dishes from scratch, very often the microwave oven is also used to defrost food in a few minutes: you will be sorry to know that this is really a bad habit. In fact, according to some research, a very fast defrosting helps the proliferation of bacteria that are naturally present especially in meat and fish: the freezing process tends to break down most of these bacteria which, however, if "awakened" too quickly, start to reproduce and can cause annoying stomach aches, if not worse. So how to defrost a food not too slowly and with an eye to our health? Simpler than we think: experts talk about the "cold chain" or a process in which foods are slowly subjected to higher temperatures: the safest way to do this is to defrost the foods by putting them in the refrigerator so that they can gradually go from a temperature below zero to an "ambient" temperature. Be careful, anyway: never refreeze a food that has already been defrosted, you risk "awakening" twice the bacteria in food.

3. Foods that can be heated in the microwave oven

What can we cook as well as heat in the microwave oven, sure to bring simple, wholesome and at the same time tasty dishes to the table? Whatever food you are going to cook in the microwave oven, always take care to use the right container that does not spoil the cooking and especially the food. In the microwave oven you can cook vegetables (except those with green leaves) and sauces, being careful not to cover the container so tightly, the meat (veal, pork or stew) that will be particularly juicy and soft thanks to fat-free cooking, but also pasta, always paying attention to the instructions and the recommended voltage.

4. Foods that cannot be heated in the microwave oven

A tool that looks like a miraculous electrical appliance and that solves all our problems: yet not all foods can be cooked in the microwave oven. Here are the foods that should not be put in the microwave oven and why:

Chicken: white meat may contain some bacteria that microwave cooking does not always manage to eradicate; it is better to choose a more classic oven cooking by induction or irradiation, less fast but more effective.

Potatoes: if you want to heat some already cooked potatoes, the microwave oven is not the best method to use. In fact, kept at room temperature, the tubers can develop the Clostridium botulinum, which the microwave magnetic waves cannot eliminate. It is better the "classic" oven or a hot pan.

Rice: the large amount of starch present in rice means that once cooked it must be consumed immediately or preserved in the refrigerator to prevent it from souring; in fact, if left at room temperature, rice becomes fertile ground for the proliferation of bacteria that the microwave oven cannot defeat.

Green leafy vegetables: green leafy vegetables (spinach, beets, but also asparagus) contain nitrates that are not in themselves dangerous to our body; however, these molecules can become carcinogenic if in contact with electromagnetic waves; so it is better not to cook them in the microwave oven.

Maternal milk and baby food: the proliferation of the waves that move the molecules present in the milk destroy some nutritional properties.

Chili: unfortunately, if cooked or heated in the microwave oven, the chili can develop toxins and become harmful to our body.

5. Containers that cannot be placed in the microwave oven

The rules we have seen for foods also apply to the containers we use and which we put in our microwave oven. Now on the market we find easily suitable containers in which to cook or heat our dishes in the microwave oven. Yet it's always good to remember which materials should never be used in a microwave oven:

first of all the aluminum, which does not let the microwaves pass but instead it reflects them, damaging the internal cavity of the oven. No then to disposable containers;

unless the contrary is expressly indicated never put in a microwave oven plastic containers which, under the influence of electromagnetic waves, could release harmful substances to our body;

no metal and pans, these tools go on the stove not in the microwave oven.

Last but not least: no paper containers that could catch fire, except for ready-made food containers which, if expressly written on the packaging, can be heated in the microwave oven.