Types and functions of microwave ovens. Technical characteristics of microwave ovens
The first to discover the possibility of microwave radiation to heat food was US engineer Percy Spencer. It was he who patented a microwave oven.
Judging by eyewitness accounts, the idea of its creation came to him when he I stood near the magnetron for several hours and found a piece of chocolate melted in my pocket.
The device is capable of heating food without heat energy and is more like a radio transmitter than the one we are used to kitchen stove. The main active element is Microwaves are a form of electromagnetic energy, like light and radiomagnetic waves.
At the speed of light they propagate towards the object in the form of ultra-high frequency waves, the length of which ranges from 0.01 to 1 m.
REFERENCE! Microwave microwaves are also used in civil radar, radio navigation, satellite television, mobile communications, etc. Microwaves are naturally emitted by the sun and are measured by certain instruments.
Microwave oven device
How does a microwave oven work? An oven with a control panel, a waveguide, a rotating stand, a transformer, a capacitor and a magnetron - these are the main building elements microwave oven.
The microwave oven operates as follows: from the control panel electricity enters the transformer, then into the capacitor, where the power is increased and transferred to the magnetron.
IMPORTANT! The filament is supplied high voltage (about 3-4 kW) so that its antenna can emit fairly strong microwave waves.
Interacts with water molecules in food an electromagnetic field with a frequency of 2450 MHz is converted by a waveguide contained in any microwave oven.
Thermal fuses or thermal relays serve to ensure the safety of the device and prevent it from overheating. 
The principle of operation of the fuse is very simple. In the place where it is necessary to control the temperature, it is attached aluminium case using a special flange connection. This ensures maximum thermal contact. The metal plate located inside the thermostat is fundamentally set to a specific temperature.
Microwave ovens also equipped with fans, which suck in air from the outside, and then distribute it inside the housing through a blower with a ventilation system. The fan motor is a conventional single-phase asynchronous motor alternating current.
IMPORTANT! To avoid turning on an open microwave, a system of three microswitches is provided. One of them turns off the magnetron. The next one turns on the backlight. And the third is designed to notify the control unit about the door opening.
To the main functions of the control unit can be attributed:
- regulation of device power;
- automatic shutdown after the programmed period.
How does a microwave oven work?
Since the microwaves produced by the oven act specifically on water molecules. In other words, all that is needed is a small amount of water in the food placed in the chamber.
Increasing food temperature in the oven under the influence of microwaves, it resembles the process when our hands warm up if we rub them hard. The similarity is also that when one palm rubs against the surface of the other, heat leaks into the soft fabrics. Microwaves work on the same principle, namely on a small surface (1–3 cm), without penetrating deep into the object. 
The emitted microwaves come into contact with water molecules, causing them to move faster and warm up the food. There are millions of molecules in a drop of water, and when a microbeam hits them, it penetrates the food to a depth of 2.5 cm, causing them to sway under the influence electro magnetic field. During this friction, heat is released.
Thus, Foods with a high liquid content heat up faster.
IMPORTANT! Scientists are still arguing about how harmful a microwave is and how it affects the quality of food. However World Health Organization States that Microwave ovens do not harm anyone, nor on the food consumed.
How additional microwave functions work
Almost all modern ovens have grill mode. When not only the chamber is heated inside, but also heat is supplied using a special awning - a curved metal device located at the top of the chamber. They are called heating elements - from “thermal electric heater”.
In modern ovens, in addition to the grill mode, there is convection mode. When the chamber is effectively blown from the grill heating element to the food. The system is a circulator. Convective heat transfer, as applied to a furnace, is the transfer of heat using air molecules. Using a fan is usually called convection mode.
Modern models have a number of recipes and cooking methods built into the computer.
Good day to all blog readers. Today let's talk about irreplaceable assistant There is a microwave oven in the kitchen. I am sure this electrical appliance helps many housewives. Do you know about all its useful functions? Let's look at whether a microwave oven can be dangerous and how the device operates. What types of models are there today?
Agree, but this device makes our life a lot easier. And its ease of use allows even children to operate it. The microwave is a great time saver. You can heat up a bowl of soup in a couple of minutes. And defrost the food in 5-30 minutes. Many people use the device exclusively for defrosting and heating. But in vain, you can cook very tasty dishes in it. And if the device has convection, even an oven. But more about this in the article “ what can you cook in the microwave».
The operating principle of the device is quite simple. The heart of any microwave oven is the magnetron. The frequency of microwaves for domestic purposes is 2450 MHz. Magnetron power in modern devices 700–1000 W. To prevent the magnetron from overheating, a fan is often installed next to it. In addition to cooling the magnetron, it circulates air inside the furnace. This also helps food heat more evenly.
Microwaves are supplied to the oven through a waveguide. It is a channel with metal walls. They are the ones that reflect magnetic radiation. When exposed to microwaves, the molecules in food begin to move quickly. Friction arises between them, resulting in the release of heat - remember physics.
This is warm and serves to warm up the food. The peculiarity of microwaves is that they do not penetrate deeper than 3 cm. Simply put, the rest of the product is heated from the surface layer. Heat further penetrates through conduction. The product is placed on a rotating plate. Constant rotation is also meant to ensure even cooking. I found a visual video for you that demonstrates the principle of operation of a microwave oven.
The microwave door protects us from microwaves. In addition, it provides visibility. She has special design– consists of glass plates, between which there is metal grid. This mesh perfectly reflects microwaves into the oven. Small holes allow you to monitor cooking, but they do not allow microwaves to pass through.
There is a special seal around the perimeter of the door. It also protects us from microwaves. If the seal is damaged, the device cannot be used.
Since metal reflects microwaves, dishes made from it are generally not suitable for cooking in an oven. In general, I also learned a lot about the features of using various utensils. I described this in the article “”.
Who came up with this “miracle”?
Having disassembled the structure of the microwave and how it works, let's take a short historical excursion.
Housewives owe this device to the American engineer P. B. Spencer. It was he who patented the microwave oven in 1946. The discovery is believed to have happened by accident. Spencer made radar equipment. And one fine day, while conducting an experiment with a magnetron, I melted a chocolate bar in my pocket. It was so open unique property magnetron - heat food.
For ordinary housewives in Europe, the microwave oven became available only in 1962. Then the Japanese company Sharp began producing household microwave ovens for heating food. In the Soviet Union, it came into use by ordinary housewives even later. Only in 1978 this device was released to the masses. However, not everyone could afford it. The first microwave ovens cost about 350 rubles. The average salary was only 200 rubles.
Gradually the prices for these products decreased. The design of the device has been improved. Microprocessors appeared that made it possible to select different cooking modes. The oven began to not only heat food. Or use it to defrost them, but also cook them. When microwave ovens began to be equipped with grills, this device became even more popular. The latest technology is convection ovens. In such a microwave you can cook the most complex dishes. Thanks to convection, the device becomes a full-fledged oven.
What types of microwave ovens are there?
Now let's talk about different types this device. This will help you make your choice if you want to buy yourself a microwave. Conditionally all electrical appliances of this type can be divided into:
- with grill;
- with convection;
- with inverter;
- with uniform distribution of microwaves;
- mini microwaves.
Now let’s take a closer look at the features of each type.
Microwave with grill
This oven is equipped with a heating element. There are two types of such elements: PETN and quartz. The heating element heater can be installed in different places. It can be on top, on the side wall, located at an angle, etc. Ten is reliable and has a low cost.
Quartz a heating element Can only be installed in one position. It is placed at the top of the oven. It is more powerful than heating element, does not take up much space, and is easy to maintain. But it also has its drawbacks. A stove with it costs more, and it is less reliable.
A microwave with grill function allows you to cook meat with a golden brown crust. Make barbecue and hot sandwiches.
Convection microwave oven
Availability this mode will be useful for those who love to bake. Convection in a microwave allows you to cook using hot air. It circulates around the dish. Thanks to this, it bakes more evenly. This is especially important for baking. The device in this case operates in microwave and convection mode. Food cooks faster, so vitamins are better preserved.
Microwave with inverter
In a conventional microwave, the power is regulated by periodically turning on/off microwave radiation. As a result, food often becomes dry. Inverter control allows you to smoothly regulate power. The built-in inverter is responsible for this. This continuous microwave exposure preserves the texture and everything useful material products.
Inverter microwave ovens work almost like ovens. Food is being prepared in a natural way, without overheating. This type household appliances appeared recently and quickly became popular.
With even microwave distribution
The disadvantage of household microwave electrical appliances is the uneven distribution of microwaves. As a result, the food may be too hot in one part and lukewarm in another. This occurs due to the concentration of microwaves in one part of the dish. To eliminate this drawback, manufacturers began to use three radiation sources instead of one.
Due to this, microwaves are distributed in different directions. They are reflected from the walls of the oven and penetrate the product from all sides. I-wave technology is very popular today. It ensures the propagation of microwaves in a spiral. The heat penetrates both the edges of the dish and the center. Attention is also paid to the design of the inner wall of the microwave. It helps microwaves to be reflected throughout the interior of the device.
Mini microwaves
Usually these are solo ovens, which are designed for defrosting and heating food. You can cook in them only the most simple dishes. In general, they are not intended for this. The main advantage of such a micro-stove is its size. small microwaves don't even have a rotating plate.
This oven saves energy and does not take up much space in the kitchen. If you plan to only heat or defrost food in it, this is the best choice.
Built-in models of microwave ovens
Separately, I would like to highlight built-in models. They can be convection, grill, inverter or evenly distributed microwaves. The main advantage is the design. You can choose either a stylish or simply ergonomic model. It can fit perfectly into any kitchen and even become its highlight.
Most often, microwaves are located in wall cabinets. This is the top row of furniture above work area. Although a microwave oven can be built underneath, it all depends on personal preference. It is very convenient to arrange built-in devices in a column, one above the other. Most models of built-in stoves have dimensions d/w - 60 cm by 35 cm. I wrote about them in more detail in the article “ built-in microwave».
For the most part, this technique is multifunctional. Built-in models have touch controls, several cooking and power modes. The doors in such devices can open either to the left or to the right. This is very convenient; you can choose the device for a specific place in the kitchen. So that opening doors do not interfere.
I hope my review will help you decide on purchasing a new assistant. As for harm, there is a lot of conflicting information about this. You can find articles saying that radiation causes cancer, etc. I ask you not to panic. Of course, microwaves can have an effect on our body. Therefore, it is better not to be near the microwave while cooking.
The main thing is that you should not dry your beloved cat in it... :) This is an assistant that is indispensable when you need to cook quickly. A microwave oven is just an addition to the main stove and oven. But very useful and necessary. What do you think?
It would seem that everyone knows everything about the “microwave”. The device has been in our kitchens for a long time. It’s already somehow inconvenient without him. It is inconvenient to quickly reheat and defrost food. Some even cook with a microwave delicious dishes. However, no matter how familiar a microwave oven may seem to us, when choosing it in a store you should take into account several points and be aware of some subtleties. ZOOM.CNews updates recommendations for choosing microwave ovens - so that when our readers come to the store, they buy exactly what they really need.
A microwave oven is a device without which it is difficult to imagine our lives. It seems that its importance in everyday life is not too great. It's not washing machine, not a refrigerator. But remember that you need to heat soup without a microwave in a saucepan, and not immediately in a plate. About the fact that meat takes half a day to defrost without a microwave oven. The fact that hot sandwiches without this oven will have to be cooked in the oven. In general, without a microwave oven, the “kitchen happiness” of most of us would be incomplete. This material covers all the main points that should be taken into account when buying a microwave.
Modern kitchen It’s hard to imagine without a microwave oven... The table below shows the main pros and cons of microwave ovensBrief historical background
The first commercial microwave oven appeared in 1947 in the USA. It was produced by Raytheon by order of the US Department of Defense - for quickly defrosting food in soldiers' canteens. The same company originally developed it. The “father” of the microwave oven is considered to be the engineer of this company, Percy Lebaron Spencer. The stove cost approximately $3,000 (very expensive at that time), weighed 340 kg, was as tall as a person, and had a power of up to 3 kW. A few years later, the first tabletop microwave oven was released in the United States, which cost about $500. Also, since 1952, microwave ovens have been produced in Japan (a patent was purchased in the USA). In the USSR, development of industrial microwave installations was also carried out. Household microwave ovens were produced in our country in the eighties of the twentieth century, and in our country only the assembly of devices from Japanese components was carried out.
How does it work
Household microwave ovens use microwaves with a frequency of 2450 MHz. This frequency is established for microwave ovens by special international agreements so as not to interfere with the operation of radars and other devices that use microwaves. The radiation source is a high-voltage vacuum device - a magnetron. A high voltage must be applied to the magnetron filament - about 3–4 kV. The mains supply voltage (220 V) is not enough for the magnetron, and it is powered through a special high-voltage transformer. The magnetron power is approximately 700-1000 W. To cool the magnetron, there is a fan next to it that continuously blows air over it. The fan provides forced convection air in the oven cavity with its simultaneous heating (from the magnetron), which promotes uniform heating (cooking, baking) of products.
The microwaves generated by the magnetron enter the oven - to the products - through a waveguide. This is a channel with metal walls that reflect microwave radiation. Complex design has a “microwave” door. It should provide the user with an overview (of what is happening inside the oven) and prevent microwaves from escaping outside. This is a multilayer “pie” made of glass or plastic plates. Between the plates there must be a mesh of perforated metal sheet. The metal reflects microwaves back into the oven cavity; small perforation holes (less than 3 mm) do not allow microwave radiation to pass through. A seal made of dielectric material is mounted around the perimeter of the door.
How food is heated
To heat food using microwaves, it must contain dipole molecules, that is, molecules that have a positive electrical charge at one end and a negative one at the other. There are many such molecules in food - these are molecules of fats, sugars and water. IN electric field they line up strictly in the direction power lines fields, “plus” in one direction, “minus” in the other. As soon as the field changes direction to the opposite, the molecules immediately turn over 180°. The wave field in which these molecules are located changes polarity several billion times per second!
Under the influence of microwave radiation, molecules rotate at a frantic frequency and “rub” one another. The heat released during this process is what causes the food to warm up. Heating of products occurs due to the heating of the surface layer by microwaves and further penetration of heat into the depths of the food due to thermal conductivity. Boiling water in a microwave does not happen the same way as in a kettle, where heat is supplied to the water only from below. Microwave heating comes from all sides. In the microwave, the water will reach boiling temperature, but there will be no bubbles.
Is microwave radiation dangerous?
It has been proven that microwaves (microwave radiation) do not have any radioactive effects on biological tissues and food. Cooking food using microwaves requires very little fat, so food cooked using microwaves is healthier and does not pose any danger to humans. Design modern stoves Strict measures are in place to prevent radiation from escaping. Direct exposure to microwaves (eg on human skin) may cause burns. But such risks correct operation A working microwave oven is completely missing. Microwaves “fade out” very quickly in the atmosphere. And already at a distance of half a meter from the microwave, the radiation becomes 100 times weaker. It is enough to move away from the stove at arm's length, and you can feel completely safe (although there is no danger near a working stove).
Types of ovens
Modern microwave ovens come in monofunctional (solo models) - only with a microwave function. They will be useful for those who rarely eat at home and are suitable for an office kitchen. You can heat and defrost any food in them and cook simple dishes.
Stores also sell microwave ovens with grills (the grill can be used separately or in symbiosis with microwaves). These are suitable not only for heating or defrosting food, but also for preparing various dishes (for example, grilled chicken, hot sandwiches, etc.). The grill can be a heating element (metal tube, spiral, with a heating element inside) or quartz (tightly twisted wire made of a heat-resistant alloy of nickel and chromium, which is placed in a quartz glass tube). The grill heating element is located in the upper part of the microwave working chamber, under the “ceiling”.
There are oven models in which the grill is movable. It can lower and move towards the back wall. If the grill is movable, it is easy to fry the product evenly and is easier to keep clean top part working chamber of the furnace.
The quartz grill is usually stationary. It is located not under, but in the “ceiling” of the working chamber, which saves space in the working chamber. It heats up faster than a heating element, is more economical, and is usually easier to clean. There are models with two grills. Most often there is a quartz on top, and a heating element on the bottom or side.
There are also multifunctional (or combination) microwave ovens on sale. In addition to microwaves and grill, there is a convection mode, as well as combined modes. There is a fan behind the wall of the inner chamber of such a microwave oven. It blows hot air and the dish, blown with heat from all sides, is evenly baked and covered with a golden crust, as if it were being cooked on a spit. In an oven with this function, you can bake everything that can be baked in an oven – even puff pastries. There are also ovens with a microwave function, with a grill, with convection and with steam processing of food (there is a steam generator).
Before buying a microwave oven, you should decide - to understand why, to a greater extent, you are buying a “microwave”. If you are going to mainly heat and defrost, take a solo model. Do you sometimes like to have hot sandwiches for breakfast? Then buy a stove with grill. If you are going to cook various dishes in the oven, take a combined oven with convection.
Working chamber volume
Also, before purchasing, you should definitely consider what size microwave oven you need. This refers to the volume (capacity) of the working chamber of the device. This figure can vary from 13 to 42 liters. The smallest ovens - up to 20 liters - have enough space for a small chicken or a plate of food. This is enough for a bachelor or a family of 2 people. If there are more eaters or friends often come over for a light, you should take a closer look at stoves with a chamber volume of 23 to 32 liters. And if you have a large family, it is better to choose a “microwave” with a chamber volume of about 40 or even more liters in order to heat it up at a time a large number of food or, on occasion, bake a goose.
Rotary table
Most modern microwave ovens are equipped with a rotating round table- it rotates so that the microwaves are evenly distributed over the product. The turntable is usually made of durable glass (but it can still be broken if handled carelessly), attached to a special rotating rod and “placed” on a stand equipped with small wheels. The diameter of the turntable depends on the volume of the working chamber - the larger it is, the larger diameter turntable. There are also models without a rotary table on sale (but quite rarely).
Power level
The power of a microwave oven is an important operating characteristic of the appliance. The power level largely determines how quickly the oven can cook a dish and heat the product. The larger the volume of the working chamber, the greater, as a rule, the power of the microwave oven. IN modern models power can be adjusted. Set minimum value, average, maximum (can be up to 10 levels, depending on the model). The microwave power in most modern household microwave ovens is 700-1000 W. Grill and convection have their own power levels (here, with rare exceptions, power level adjustment is not available).
Microwave Uniform Distribution System
To ensure that microwaves are distributed evenly in the working chamber and not concentrated on only one part of the dish, many modern “microwaves” have several (two or three) sources of microwave radiation. They emit wave beams in different directions, which, repeatedly reflected from the walls, are evenly distributed throughout the entire interior of the furnace.
Inverter microwave ovens
Inverter microwave ovens are now sold in stores. In such furnaces, the magnetron power decreases and increases smoothly. The magnetron does not turn off (and in “ordinary” furnaces, its operation circuit is discrete - it works intermittently and when turned on, it always “produces” the full power set by the user). Continuous “soft” penetration of microwave energy into the product in such an oven helps preserve its texture and nutritional properties; such ovens are more economical and durable.
Software
A few words about the basic cooking programs implemented in modern microwave ovens. Automatic cooking means recipes for preparing various dishes stored in the oven’s memory. These are algorithms for the operation of the oven, relevant for the preparation of certain products, dishes (their “list” and quantity depends on the brand and model of the oven) - power level, time, combination of modes (for example, first cooking in the “Microwave” mode, and then turning on grill). It is enough to select the type of product or a specific dish using the control system, enter the weight of the product, and leave everything else to the oven. Number of automatic cooking modes in different models may vary. There are also “microwaves” with the ability to program auto-cooking by the user (the oven “remembers” the cooking algorithm entered by the user).
Automatic defrosting. It’s convenient to avoid guessing how long it will take to defrost a particular product. Simply select the type of product, enter its weight, place the product in the working chamber and press the “Start” button. The oven itself “knows” how long it will take to defrost your meat, fish, chicken, vegetables or bread, and at what power the defrosting will take place.
Defrosting can also be “normal” - not automatic. In this case, you set the defrosting time yourself. In principle, you can defrost food in any microwave, even one that does not have a “Defrost” program at all (by setting the minimum microwave power). However, a special mode allows you to do this faster and more efficiently.
Automatic heating. Almost the same as auto defrosting. The algorithm is the same. You choose the type of product, its weight or volume and turn on the stove, which will independently “decide” how long it will take to heat up, for example, a bowl of soup, and at what power to produce it. There can be several auto-heating programs for different products.
Microwave+Grill mode. In that combined mode The dishes turn out evenly baked and with a golden brown crust. “Microwaves + Convection” - food cooks faster, preserves the natural taste and appearance of products to a greater extent, and more vitamins are retained in them. It is especially good to cook dough products with a large amount of liquid and wet ingredients in this mode (pies with vegetable, fruit or berry filling). “Grill + Convection” - mode for preparing crispy and crispy dishes. Good, including for baking.
Cleaning the stove with steam. The program is only relevant for microwaves with a steam generator. Allows the microwave oven to carry out almost independent cleaning of the internal volume. The process uses steam energy to dissolve grease and contaminants. To start the program, you simply need to pour water into a special container provided by the stove design, add detergent and activate the process by pressing a button. Cleaning usually takes 10-15 minutes.
Microwave oven control
Modern microwave ovens have electromechanical, push-button and touch controls. Electromechanics are two rotary controls. One sets the power and operating mode. Another is the operating time of the oven. Most often, such control is used in solo stoves and stoves with grill. Electro mechanical control– simple, understandable, convenient.
Push-button control allows for more precise programming of the furnace operation. Typically, the power level, mode, and cooking time are set by one or several presses of one or another button. All settings, as a rule, are reflected on the display (most modern microwave ovens, except ovens with electromechanical control, have one). The only negative is that over time, dirt can get clogged under the buttons - it can be difficult to wash it out.
Touch electronic control. Essentially, these are the same buttons, only “recessed” into the body. There are many such models in stores - this is now the most popular type of microwave oven control. This is understandable, because touch control is very convenient - all settings are made with light touches of your fingers to the sensors. There are no problems when cleaning, because the touch control panel is a flat surface. There are stoves with combined system controls (buttons and sensors).
The three types of control described above are the main ones. But there is also a fourth type. It is less common. We are talking about the so-called “tactile” electronic control. Usually in this case there are also one or two rotary programmer (often they are recessed), but the result of the manipulation (rotation of the programmer) is displayed on the display. Many modern microwave ovens have an interactive mode, when the display shows recommendations to the user.
Internal coating of the working chamber
The working chamber of a microwave oven can have enameled walls - the most cheap option. Enamel is good because it is easy to wash and clean. But long-term high temperatures such surfaces are contraindicated. Therefore, this coating is used in inexpensive stoves (usually only solo models). Stainless steel(another option for internal walls) can withstand the “hottest” modes provided in a microwave oven. But it is more difficult to keep clean. To bring shine to “stainless steel”, you will sometimes have to clean it with a sponge or brush, but not too hard, so as not to scratch the walls. Another option is ceramic or bioceramic coating. It is durable, smooth (and therefore easy to clean), resistant to scratches and carbon deposits.
Microwave oven accessories
The delivery package of any modern microwave oven, in addition to the device itself and the instruction manual, includes additional accessories. These are, for example, high and low grills for frying (relevant for ovens with grills and multifunctional ones; the set may include both, or there may be one, usually high). The delivery set may also include various trays, dishes, a spit, and a stand for baby bottles. If you choose a microwave oven with a large chamber, it would be nice if it comes with a “multi-story” plate stand to heat food for several people at once. There are stoves with containers for baking bread and a set of utensils for steaming dishes. It is better to stock up in advance with special utensils for cooking in a microwave oven. You can place any dishes, even paper cups, under microwave radiation. The main thing is no metal! Even the gold edges on cups and plates begin to sparkle under the influence of microwaves.
Main manufacturers
Microwave ovens are now produced by many well-known and not so well-known companies. However, perhaps not all of them can be considered the main manufacturers, but those who have long proven themselves in this segment. In stores, pay attention to stoves from the brands Bosch, Daewoo Electronics, Hansa, LG, Moulinex, Tefal, Samsung, Electrolux, Gorenje, Sharp, Panasonic, Whirlpool...
In the ZOOM.CNews product catalog you will always find the microwave oven you need, other kitchen and household appliances, photographic equipment, digital electronics. Here you can get acquainted with the main operating characteristics of the devices, find out the opinions of other users about them, or leave your review. You can also compare prices for the necessary equipment in different Russian online stores. Choose, buy, use!
A microwave oven, or microwave, is an almost indispensable attribute of any Russian kitchen. Why is this household appliance so common? The point is its speed - heating time in a microwave oven is measured in seconds, whereas on the stove it will take much longer. Convenience also plays an important role - the microwave is small in size and will fit even in the smallest Khrushchev apartment. What if there is no stove and there is no way to install it? A microwave can replace it in many ways!
How the microwave came into being
The American physicist Percy Spencer is rightfully considered the “father” of the microwave oven. He developed ultrahigh frequency emitters, and during his experiments he noticed that organic matter heats up under the influence of microwaves. How exactly this happened, history is silent, but there are two most common versions: according to one of them, he absent-mindedly forgot a sandwich on the device that was turned on, and when he remembered it, it was already very hot. The second version claims that Spencer carried a chocolate bar in his pocket, which naturally melted under the influence of ultrahigh frequencies.
Domestic use
One way or another, having discovered the “food” properties of microwave radiation in 1942, already at 45 the physicist received a patent for his invention. And just two years later, in 1947, the American military warmed up their breakfasts, lunches and dinners in the microwave. Whatever the microwave did, the military did not care about the operating principle of its mechanism - the main thing was that it gave quick results. True, the microwave oven in the 40s was still “not the same” - the weight of the device exceeded 300 kilograms!
Then the Sharp company got down to business - already in 1962 it released the first model of a consumer microwave oven to the people. It did not cause a particular surge of interest, because buyers were scared off by the use of microwave radiation. Later, the same company invented the “rotating plate”, and in 1979, an electronic control system.
What does a microwave oven consist of?
A microwave oven consists of several required parts:
- Transformer.
- The magnetron in the microwave is actually an emitter
- A waveguide through which radiation is transmitted to an isolated chamber.
- The metallized chamber is the place where the food is heated.
Additional elements of the microwave are: for more uniform heating of food, electronics for controlling various modes, a timer, and a fan.
How does a microwave heat food?
Despite the apparent “magic” that a microwave oven has, the principle of operation is absolutely scientific and logical. Almost any food contains molecules of water and other elements that have both positive and negative charges. In the absence of a magnetic field, the charges in the molecules are arranged arbitrarily, chaotically. A strong magnetic field instantly organizes electric charges - they become directed strictly in accordance with the course of the magnetic field lines.
The peculiarity of microwave radiation is that it “turns over” dipole molecules not just quickly, but unimaginably - almost 5 billion times per second! The molecules move in accordance with the changing magnetic field, and the high speed of “switching” literally creates a friction effect. This is why food is heated in a microwave oven in a few seconds.
Types of Microwave Ovens
What types of microwave ovens are there and how they differ from each other:
- Solo oven, or ordinary microwave. It is one of the most budget models and is intended only for defrosting and heating food. As a rule, such microwave ovens are mechanically controlled and are quite reliable, since there is nothing special to break.
- Microwave with grill and convection. These microwave functions can be used both together and separately. The grill consists of an additional heating element, which is most often located under the ceiling of the chamber, and a rotating spit. Convection is the circulation of hot air inside the chamber, which provides additional and more uniform heating of food. Such microwaves, as a rule, belong to the average price category and operate both mechanically and electronically.
- Multifunctional microwave ovens. Many modes, of course, convection and grill, a double boiler function, as well as a whole range of culinary solutions for your kitchen. Of course, so serious Appliances are classified as expensive and controlled using sophisticated electronics.
Despite the differences in details, a microwave oven for 20 dollars and one for 200 are still the same microwave. The operating principle is the same.
How else do microwave ovens differ from each other?
- Volume. Household microwave ovens differ from each other, but not too much. But industrial microwaves are completely different - they can heat several dozen portions at once.
- Grill type. It can be ceramic, quartz or PETN. With the same semantic load, they differ in details: for example, a quartz grill heats up more evenly and spends less electricity, but a heating element can work more intensely and is also easier to clean.
- Method of covering internal walls. There are also several of them - enamel paint, durable enamel and special coatings (bioceramics and antibacterial). Painting is the cheapest and short-lived; enamel is already better, although prolonged and intensive use also renders it unusable. Special coatings can be called eternal. Disadvantages include high price and fragility in relation to shock loads. And yes, there is also stainless steel - great option for those who are not ready to fork out too much for a microwave. Durable, reliable, great-looking coating can easily withstand prolonged and intense heat. The disadvantages of stainless steel include difficulty in washing - several cleanings with abrasive agents create a network of micro-scratches on its surface, into which burnt fat “clings” with all its molecules.
- Types of management. There are only three of them - mechanics, buttons. The mechanics are cheap, easy to use, reliable, the disadvantage is the accuracy of timing. The buttons break a little more often, but the time can be set second per second. Disadvantages include dirt accumulating on the controls, which requires additional time for wiping. The sensor is beautiful, stylish, dirt does not accumulate, you can program the cooking process. Disadvantages - it breaks more often than others, it costs significantly more. Repairing microwave ovens, especially expensive ones, is not a cheap service, so it’s worth thinking about: is it worth getting one with a sensor?
- Microwave oven operating modes. There can be from 3-4 of them in cheap models, to 10-12 in the most expensive ones. The main modes include the following: full mode - frying meat, baking vegetables. Medium-high, 3/4 power - quickly heats undemanding foods. Medium - cooking soups, cooking fish. Medium-low, 1/4 power - defrosting food, “soft” heating of food. The smallest, about 10% power, is intended for defrosting “capricious” foods like tomatoes, and keeping already hot foods warm.
Additional functions of microwave ovens
One of the most interesting additional functions for a microwave oven is the supply of hot steam. This addition prevents the food from drying out, and it also cooks much faster. Here you can also add ventilation of the chamber - despite its apparent insignificance, for many housewives this function has become a life-saver - now their vegetables do not smell like fish, and fish do not smell like apples.
Chamber dividers. Different grates allow you to cook several portions at the same time. The disadvantages of this function include the lack of rotation, which makes heating of food less uniform.
“Crisp” is a special plate for the microwave that allows you to cook in it the same way as in a frying pan. Made from it “holds” temperatures up to 200 degrees.
Mica. Why is mica in the microwave? It protects the waveguide from various contaminants, and increases the service life of the device.
Dual emission function. How does this microwave work? The design and operating principle of such a microwave oven differ only in the presence of two sources of high-frequency radiation. This allows for better and more uniform heating of food.
Built-in cookbook. It’s not a cheap feature, but for those who like to eat delicious food without spending a lot of time and money on it, this is it.
Necessary safety rules when using a microwave oven
Quite often, ordinary people are concerned about the question of whether a microwave oven is hazardous to health. Its operating principle, of course, is based on microwave radiation. But there is no need to be afraid of this.
A fully functional microwave oven poses no more danger to the consumer than a computer or TV. Contrary to persistent myths, radiation from a microwave oven is not radioactive or carcinogenic, and a microwave oven does not begin to “fog” after a couple of months of operation.
Microwave radiation can indeed cause serious burns, but to achieve this from your home microwave, you will have to work hard - even the cheapest models are equipped with multi-level protection. And, for example, you won’t be able to put your hand into a switched-on device - the automation will immediately turn off the power.
What dishes should you use in your microwave oven?
It is best if the microwave plate that you are going to use in the microwave oven is specialized, with appropriate markings. This includes, for example, sets of cookware made of heat-resistant glass. If you don’t have one at hand, then pay attention to the following recommendations:
- Glass. Excellent material for the microwave, as long as it is not too thin and there are no cracks or chips.
- Porcelain and faience. Suitable materials are provided that they are completely glazed and not painted with metallic paint. Again, porcelain or should not have mechanical damage.
- Paper. Suitable material, but with assumptions - the paper should be thick, not colored, and it is better not to use it for a long time.
- Plastic. Yes, but only specialized ones. Today, many companies produce entire lines of plastic containers for heating in microwave ovens. Perfect option for an office worker who doesn’t want to splurge on business lunches and trips to cafes.
The most unsuitable plate for the microwave is a metal one. High-frequency radiation causes it to spark, which will soon send you looking for a place where microwave ovens are repaired.
How to care?
The microwave instructions will help you with this. It indicates what special detergents it should be cleaned. There is no shortage of them, and it’s worth buying them right away, with a microwave. Do not delay cleaning - you will have to scrub off the repeatedly heated and compressed fat on the walls of the chamber for a painfully long time, cursing everything in the world, and daily cleaning will come down to a few light movements with a rag. If you still achieve the formation of “ancient deposits,” then before washing, put a glass of water in the oven for a minute and turn on the maximum mode. Grease and dirt will accumulate and wash off much easier.
A little humor...
One lady in the US won a lawsuit after she “dried” her cat in the microwave. IN statement of claim she indicated that she did not know that “you can’t dry cats in the microwave.”
Despite the well-known fact that raw chicken eggs explode in the microwave, enthusiasts around the world are trying to come up with a way to get around this problem - pierce a hole in the shell, wrap it in a special film. But despite all their efforts, the eggs still explode.
Recently, a fake message exploded on the Internet that new model The iPhone can be recharged from the microwave. It is unknown how many smartphone owners fell for this prank, but dozens of photos with damaged iPhones speak for themselves.