Equipment with direct heating. Modern equipment of the dining room of the business center: how and what to feed people deliciously? Electronic control type
1. Classification of equipment of thermal shops
The equipment of thermal shops is divided into three groups: basic, additional and auxiliary.
Main the equipment is used to perform heat treatment operations and includes furnaces, heating installations, cooling devices (hardening tanks, hardening machines, cold treatment equipment, etc.). The classification of the main equipment of thermal shops is shown in Figure 1.1.
Rice. 1.1. Classification of the main equipment of thermal shops
To additional equipment includes equipment for straightening and cleaning parts (straightening presses, pickling baths, sandblasting and shot blasting machines, washing machines, etc.). The classification of additional equipment for thermal shops is shown in Fig. 1.2.
Fig 1.2. Classification of additional equipment of thermal shops
Auxiliary equipment includes carburettor and controlled atmosphere preparation units, quench fluid coolers, sanitary equipment, overhead and slewing cranes, monorails with electric hoists, roller tables, conveyors, conveyors, etc. The classification of auxiliary equipment of thermal shops is shown in fig. 1.3.
Fig 1.3. Classification of auxiliary equipment of thermal shops
Furnaces and heating installations are classified according to their technological purpose, according to the type of thermal energy, according to the method and degree of mechanization, according to the use of various media during heating.
By technological purpose furnaces and heating devices are divided depending on the operations for which they are intended, into annealing, hardening, tempering, carburizing, etc.
By type of fuel or thermal energy used furnaces and heating devices operate on liquid, gaseous fuels and electricity.
By method and degree of mechanization furnaces are divided into pusher, conveyor, carousel, drum and others. These ovens may have devices for manual loading and unloading of products, for automatic unloading, etc.
By the use of various media for heating furnaces and heating devices are classified into furnaces with controlled atmospheres (neutral, carburizing), furnaces-baths with molten salts and metals.
2. The main equipment for heating materials and products
2.1. Furnace indexing
First letter index indicates the type of heating. The letter adopted for electric ovens FROM(resistance heating), for fuel stoves - letter T(thermal flame) or letter H(heating flame).
Second letter The furnace index indicates the main design feature of the furnace. The following main designations are accepted: H– fixed hearth furnace; D- a bogie hearth oven; W– mine (round); L- tunnel; G- hood; E– elevator (furnace with lifting hearth); T- pusher;
To– oven with conveyor hearth; E– oven with overhead conveyor; R– oven with roller hearth; YU– walking hearth oven; And– pulsating hearth furnace; B- drum; BUT- carousel (with a rotating hearth or vault);
I- pit stove; SCH– slot furnace; At- methodical (blacksmithing).
B (bath) - the second letter of the index for furnace-baths and electrode-salt baths.
Third letter The index of ovens indicates the nature of the environment in the workspace. For electric resistance furnaces, the following designations of atmospheres are accepted: O– oxidizing; Z- protective; AT– vacuum; H- hydrogen; BUT- nitrogen.
Third letter index for ovens-baths is indicated: M- oil; G- molten metal, salt or alkali, and for fuel furnaces - indicates the nature of the environment in the working space: O- oxidizing (that is, ordinary furnace); Z- artificial (protective, non-oxidizing, for cementation, etc.).
fourth letter index indicates the individual characteristic features of the furnace. The following designations are accepted: BUT- the furnace is included in the unit, that is, it can be aggregated with a hardening tank and other equipment; AT- vertical arrangement of the furnace (in furnaces of circular cross section) or vertical movement of products (in mechanized furnaces); AND- grooved under the furnace; To- well furnace (periodic action) or annular hearth (in furnaces with a rotating hearth); T- plate hearth (in furnaces with a rotating hearth); M– the furnace is mechanized; H- Continuous furnace (drum); P- Batch oven (drum).
The numbers after the letters with a hyphen indicate the dimensions (in decimeters) of the working space of the furnace (or the dimensions of the muffle, retort).
For furnaces with a rectangular section of the working chamber, the first digit indicates the width of the hearth, the second - the length of the hearth, the third - the height of the chamber (or the loading window, if the height of the window is less than the height of the furnace chamber).
For round furnaces (shaft, well, etc.), the first digit indicates the diameter of the chamber, the second - the length of the chamber.
For rotary hearth ovens, the first number indicates the outer diameter of the hearth, the second the inner diameter of the hearth, and the third the width of the hearth.
The numbers indicating the dimensions of the hearth chamber, window and retort are separated by dots.
The limiting temperature of the furnace (in hundreds of degrees Celsius) is given in the denominator (through a slash).
For fuel stoves, next to the number indicating the temperature of the stove, a letter indicating the type of fuel is put through a hyphen: G– natural or other gas; M– oil or other liquid fuel, for example, the stove index.
SKZ-12.70.01/7 reads as follows: electric oven, with a conveyor hearth, with a protective atmosphere, hearth width 12 dm, hearth length 70 dm, chamber height 1 dm, temperature limit 700 °C.
The index of the furnace TTZA-8.72.8.5 / 9.5-G is read as follows: fuel furnace, pusher, with a protective atmosphere, aggregated, hearth width 8 dm, hearth length 72 dm, chamber height 8.5 dm, temperature limit 950 °С, on gas fuel.
By technological purpose thermal devices are divided into cooking (digestion boilers, steamers, electric cookers, coffee makers), frying and baking (ovens, baking and pastry cabinets, frying pans, deep fryers, grills), multifunctional (cookers, microwave ovens, combi steamers), water heating (water heaters and boilers ) and devices for keeping cooked food hot - devices for distributing lines (bain-marie, thermal display cases and cabinets, thermoses, thermal containers).
Depending on the type of energy carrier, all thermal devices for public catering are divided into two main groups: electric and gas. For operation in the "field" conditions, fire equipment is produced that runs on solid fuel - wood, coal, shale, etc.
In electric thermal devices, the main element is an electric heater, in which electrical energy is converted into thermal or electromagnetic field energy. The main advantages of electric energy include: simplicity and compactness of electric energy converters into thermal energy, simplicity and reliability of control of electrothermal devices, the possibility of prompt and accurate accounting of electricity consumption, good sanitary and hygienic conditions in production, relatively high efficiency of the devices.
In gas thermal devices, natural, artificial or liquefied gas is used as an energy carrier. The advantages of gas appliances include good sanitary and hygienic indicators, the possibility of automatic control of the thermal regime and a high coefficient of performance (COP). The disadvantages include the ability of combustible gases to form an explosive mixture with air, which implies special conditions for their operation.
According to the method of heating, contact thermal devices and devices, which are surface heat exchangers with direct and indirect heating.
Thermal devices, in which the product is processed directly on the heating surface, are called conductive. Frying surfaces and grills operating on this principle are increasingly called contact.
According to the structure of the work cycle thermal devices, used in public catering, are divided into devices of periodic and continuous action.
By geometric shape thermal devices are subdivided into non-sectional modulated (having different dimensions and a cylindrical shape, which does not allow such equipment to be installed in line with other devices without gaps) and sectional modulated rectangular shapes, the design of which is based on a single size - a module (such equipment is developed for installation in line, where the determining dimension is depth, for example, thermal electric lines 700 of the Italian company Magepo and 900 of the Slovenian company KOGAST).
All thermal devices regardless of the technological purpose and design solution, they consist of the following main parts: working chamber (surface), heat generating device, apparatus body, thermal insulation, casing, base, instrumentation, automatic control devices and fittings.
The working chamber is intended for thermal processing of foodstuff. Its shape and dimensions depend on the technological purpose of the apparatus (reservoir, fryer bath, combi steamer chamber, heating surface or frying pans). It can be mobile and immobile.
Thermal insulation reduces the heat loss of the device to the environment and is made in the form of layers of special materials on the outer surface of the working chamber.
The casing is used to protect the insulation from the effects of air moisture and destruction and gives the device an aesthetic appearance. The base serves to mount the body of the apparatus and is most often made in the form of cast iron, duralumin or plastic of various shapes.
Control and measuring devices and automatic control devices, as well as fittings, are used to turn on, turn off, control the operation of the apparatus, regulate the thermal regime and safe operation of the apparatus.
Public catering establishments use modern machines and apparatuses in full force, which mechanize food processing processes and facilitate the work of kitchen workers. At the same time, machines increase labor productivity, increase the output of finished products, and contribute to the expansion of the range of dishes.
In order to properly operate the machines, all catering workers are instructed, study the rules for the use of technical equipment. They must have practical skills in using machinery, be able to do daily maintenance of each machine.
Each machine or device comes from the factory to the enterprise with an instruction, with a detailed description of the relevant equipment. Employees must strictly follow these instructions.
In case of malfunctions that occur during the operation of technological equipment, it is necessary to contact specialists. Installation, repair, replacement of parts, troubleshooting can only be carried out by specialists who have the right to perform these works.
The main types of technological equipment of a modern catering enterprise are given below, and a description is given of the most important machines for processing raw materials, heating and refrigeration equipment, dishwashing machines, boilers, tools, etc.
mechanical equipment
Mechanical equipment includes machines for processing meat, fish, vegetables, for preparing dough, for cutting bread, sausages and cheese, for grinding coffee, etc.Universal drive with a set of machines
With the help of a universal drive, it is possible to mechanize the main processes of processing products. The universal drive is an electric motor with a gearbox that is connected to different interchangeable machines. To connect to the drive, the replacement machine is inserted into the socket located on the drive housing and secured with a wing screw.The drive motor is connected to the mains with a cord and plug. In the workshops for these purposes, socket outlets are installed for switching on. Drive motor power from 0.6 to 1.7 kW, depending on the model. The universal drive is moved on a special trolley from one workshop to another.
The drive is equipped with the following machines: meat grinder, potato peeler, vegetable cutter, masher, beater-kneader, etc. Each of the listed machines is connected to the drive as needed.
With their help, they make minced meat and fish, prepare creams, cut raw and boiled vegetables, wipe vegetables, meat, cottage cheese, etc.
Universal drives can be of different capacities, with a different set of machines, designed for enterprises of large and small sizes.
Interchangeable Universal Drive Machines
Meat grinder prepares minced meat and fish. The productivity of the meat grinder is from 40 to 200 kg per hour.
Beforehand, the meat is cleaned of bones, veins and films, cut into pieces of 80-120 g, put into a funnel using a wooden pusher. Minced meat can be obtained with a larger or smaller diameter, depending on the installed grate. You can skip the minced meat twice, getting even less meat grinding.
potato peeler peels potatoes, beets and other root crops.
The process of peeling potatoes and root crops is carried out by rubbing the tubers against the wavy surface of the disk, which is covered with an abrasive mass. First, the tubers fall on a rotating disk, then, under the influence of centrifugal force, they are thrown to the walls of the chamber, the walls also have a ribbed surface. The balls bounce off the walls and again fall on the disk, and so on. As a result, the tubers are peeled. In the process of rubbing the tubers, water constantly enters the chamber through the sprinkler. Clean tubers are removed through a hermetically sealed chamber door and fall into a substituted container. Loading and unloading of potatoes takes place without stopping the machine.
The cleaning process of one load lasts 2-3 minutes. Depending on the model, from 2.5 to 5 kg of root crops can be loaded into the machine. The machine is capable of cleaning from 40 to 70 kg per hour. To speed up the cleaning process, root crops are sorted by size and washed before loading.
vegetable cutter cuts raw and boiled vegetables.
Prepared vegetables are loaded into the receiving hopper and immediately fall under the cutting knives and combs, which cut them into slices. The vegetable cutter has several removable discs that allow you to make different types of cuts: cutting into slices of different thicknesses, cutting into straws and chopping. Depending on the thickness and type of vegetables, as well as on the model of the machine, from 250 to 600 kg of vegetables can be processed per hour.
Rubbing machine necessary for mashing and rubbing vegetables and fruits, boiled meat and cereal products, cottage cheese, curd mass, etc.
The product prepared for rubbing first enters the receiving funnel, and from there into the working cylinder, where it is crushed with sickle-shaped knives, and is fed to the metal grate by a rotating screw. Further, through the holes of the grate, the product is pressed into the substituted container.
Boiled meat is pre-cut into small pieces and passed through a meat grinder. Bones from fruits and berries are removed before loading into the machine. Potatoes are only mashed hot.
The productivity of the machine, depending on the model and type of products, ranges from 250 to 500 kg per hour. The machine has interchangeable grids with holes of different diameters.
Beater-kneader kneads dough, beats egg whites, prepares creams, mousses, etc.
After loading the product into a removable tank with a capacity of 20-25 liters, it is processed with replaceable beater arms. Beaters come in different shapes. The beater rotates inside the tank, while simultaneously moving around its axis. By shifting the gearbox handle, the beater can change the speed of rotation.
The processing of steep dough, thick and viscous products is carried out at low speeds. Complete processing of products takes from 15 to 40 minutes.
Extractor designed for squeezing juices from vegetables, fruits and berries. It is a screw press and consists of a housing inside which a conical screw rotates. At the bottom there is a grate, and at the bottom there is a loading funnel. The product is loaded into the funnel, captured by the auger and compressed. The squeezed juice flows out through the holes of the grate into the substituted dishes. Solid waste exits through another opening, the size of which is adjusted by a screw. The productivity of the extractor is 40-50 kg per hour.
In small enterprises, along with a mechanical juicer, they are used to squeeze juices. hand press. It consists of a lattice cylinder, to which is attached a movable lever with a disk that freely enters the cylinder. The product is loaded into a cylinder and compressed by a disk using a lever. The juice comes out through the holes of the cylinder and flows into the pan on which the press is placed.
Specialized universal drives
In addition to the universal drive, the industry produces specialized universal drives with a set of machines for meat, vegetable and confectionery shops of large catering establishments.Machines with individual electric drive
Catering establishments use machines with an individual drive, such as mechanical meat grinders, potato peelers, mashers and other machines.The meat grinder is mechanical. Mechanical meat grinders are available in different sizes and types, with different capacities. Meat grinders installed on the table have a capacity of 80-130 kg per hour, floor (stationary), large sizes have a capacity of up to 400 kg per hour. The electric motor of a desktop meat grinder has a power of 0.6 to 1 kW, and a stationary one - up to 2.8 kW.
Machine for loosening meat. For processing (loosening) pieces of meat intended for the preparation of rump steaks, chops, steaks, etc., a meat loosening machine is used. Pieces of meat, laid on a round plate and pressed down by a grate with longitudinal holes, are cut with the help of lowering disc knives by about 1/3 of their thickness, first in the longitudinal, then in the transverse directions. These cuts increase the frying surface and also cut the fibers that can compress the pieces of meat when frying. If necessary, pieces of meat can be cut on the reverse side. The machine is powered by turning the handle.
Mechanical potato peeler. A mechanical potato peeler is mounted on the floor, the electric motor is located on the machine frame. Such a potato peeler has a capacity of 150 to 400 kg per hour, an electric motor power of 0.4 to 1 kW.
Rubbing machine. The machine is installed on the floor. Its productivity is from 300 to 600 kg per hour.
Dough kneading machine. Such a machine consists of two parts: a beater and a mobile bowl. The bowl is filled with all the products that are included in the dough recipe, rolled up to the beater and placed under the kneading lever. When the machine is turned on, the bowl begins to rotate around its axis, and the beater lever makes reciprocating movements. After kneading, the machine is stopped, the dough is taken out and sent for fermentation.
Dough rolling machine. The car is intended for rolling out of all types of the test; she rolls out dough for various puff products, noodles, dumplings, brushwood, etc.
The dough is placed on the upper conveyor of the machine, and an endless belt passes between the rollers and rolls the dough between them. Getting on the belt of the lower conveyor, the dough is sent between the second pair of rolling rollers and then to the movable table of the machine. The table has a reciprocating motion, as a result of which the dough is laid on it in layers. The gap between the rolling rollers can be adjusted from 1 to 50 mm.
In one pass between the rollers, the thickness of the dough can decrease by no more than 10 mm. If a thinner layer is required, the dough is re-rolled. To do this, the dough is again sent to the upper conveyor, the gap between the rolling rollers is reduced, while the machine is not stopped. Rolling the dough can be repeated until the required thickness is reached.
On such a machine, you can roll up to 60 kg per hour. The weight of one portion of the dough is 10-12 kg. The width of the conveyor belt is 60 cm. The speed of the conveyor belt is 10 cm/sec. Electric motor power 0.6 kW.
Bread cutter. With the help of a bread slicer, you can cut slices of bread of various thicknesses. The shaped bread is placed on the receiving tray of the machine and fixed with a folding clamp of the carriage with needles. After turning on the electric motor, the lead screw moves the carriage and feeds the bread to the circular knife. The rotational movement of the knife is linked to the movement of the mechanism that feeds the bread. At the moment when the knife is in the lower position, the carriage stops: it receives translational movement when the knife is in the upper position and the opening for the passage of bread is free. The sliced bread is collected in a tray located on the left side of the machine.
The bread slicer can cut bread slices from 3mm to 16mm thick.
The circular cutter of the machine makes 179 cuts per minute. Electric motor power 0.27 kW. The maximum travel of the carriage is 45 cm. The hole for the passage of bread has a size of 15x19 cm. If the size of the bread (loaf) is larger than the size of the hole, then the bread is pre-cut lengthwise. The car is supplied with the device for sharpening of a disk knife.
In catering establishments, bread slicers with a capacity of up to 300 kg are used. Bread slicers of this power are installed at large enterprises. Small enterprises often install not mechanical bread cutters, but lever cutter knives, with which bread is cut. Bread cutters are used instead of conventional knives.
Universal ham cutter. This machine cuts ham, sausage, cheese and fish specialties into slices. First, the product is fixed on the receiving platform. It reciprocates and feeds the product to the rotating disc knife.
Cut slices are automatically stacked. The machine is started by pressing the switch button. At the end of cutting the product, the machine stops automatically. The thickness can be adjusted from 0 to 3.5 mm. The knife of the machine makes 41 revolutions per minute. Electric motor power 0.27 kW. The car is supplied with the device for sharpening of a disk knife.
Egg cutter. With the help of an egg cutter, hard-boiled eggs are cut into slices for salads, sandwiches, cold snacks. An egg cutter is made of a metal case in the form of a curved lattice with a recess for eggs and a movable rotating frame with stretched steel strings. When the frame is lowered, the strings cut the eggs into even, neat slices of the same thickness.
Mill for coffee. The coffee grinder grinds roasted coffee beans. The stand-column serves as a support for the electric motor and the machine body. Inside the case there are two millstones in the form of discs with teeth on the end surface. One of the millstones rotates together with the motor shaft, and the other has no rotational movement, but moves along the axis of rotation of the first millstone, as a result of which the gap between the teeth of the disks changes. The gap can be adjusted from 0.5 to 2.5 mm, which provides a different degree of grinding coffee - from the finest to coarse grinding.
Up to 2 kg of coffee can be poured into the hopper located at the top of the coffee grinder. The bunker is closed with a lid. The flow of grains from the hopper to the mill is controlled by a damper. Ground coffee is poured through the hole into the substituted container.
Mill productivity up to 16 kg per hour. Electric motor power 0.6 kW.
Along with machines with electric drives, manual machines are also used in small enterprises.
Thermal equipment
Thermal equipment includes stoves, cooking pots, electric frying pans, frying and confectionery cabinets, etc.Depending on the type of fuel and method of heating, thermal equipment is divided into electric, gas, steam and fire.
The most convenient and hygienic is thermal equipment with electric heating. Such devices are always ready to work, provide uniform heating, allow you to easily adjust the temperature regime, both on the frying surface and in cabinets. When working with electric heaters, there is no smoke and soot, the air remains fresh, which is a good climate for personnel to work. They are the least dangerous in terms of fire. All these positive qualities of electrical equipment lead to the fact that modern enterprises equip their kitchens with them.
The main type of heating equipment is a stove. Each stove has a frying surface on which the cookware is placed. Most stoves have ovens, and on some stoves, in parallel with frying and cooking, water is also heated in water heaters for sanitary and other production needs.
Electric stove
In catering establishments, the most common is an electric stove with a frying surface of 1 m2. On the frying floor there are six rectangular cast-iron burners; encircling the frying floor is a flat frame made of stainless steel. Electric heating elements are mounted inside the burners. All burners have different power and the highest heating temperature. So, two medium burners have a power of 4.5 kW and the highest degree of heating of the frying surface - about 450 °; four outer burners have a power of 3.5 kW and a heating temperature of about 400 °. Each burner has three levels of heating and is disconnected from the mains independently using a switch.
The burners lie freely on supports, which are fixed on the stove body. The height of the supports may vary. Under the burners is a retractable tray to catch spilled food.
Inside the body of the electric stove there is an oven with a hinged door. The heaters are located in the upper and lower parts, which ensures a uniform thermal effect on the product. The temperature inside the oven is set and controlled by two switches. Also, the cabinet is equipped with a thermostat, which automatically sets the temperature in the range from 100 to 350 °. The product on the trays is loaded into the oven only after the set temperature has been reached. The temperature in the oven is set by the thermostat before switching on.
Burners and oven can work at the same time. The maximum power consumed by the electric stove is 27.5 kW. Before cooking, the burners are heated to full power, then the heating of each burner is adjusted depending on the requirements of the technological process. Bringing to readiness of culinary products is carried out at low temperatures.
Along with rectangular stoves, kitchen electric stoves are also used.
Electric tabletop
This stove is used for frying culinary products directly on the frying surface of the burner (without a frying pan).The frying floor of this stove is a cast-iron rectangular burner with an area of 0.25 m2, along the edges of which there are grooves for draining fat on all four sides.
An electric heating element is mounted inside the burner. The switch is located on the plate body. The plate has three various degrees of heating. The maximum power consumed by the table top cooker is 2.5 kW.
Pancakes, pancakes, scrambled eggs, meatballs, fish are fried on the frying surface. Before starting work, the frying floor is lubricated with grease.
Gas stove
The frying surfaces of gas stoves are divided into two types according to the device: hotplates with open burners and stoves with a combined frying surface.Hobs are equipped with several independent burners. Each burner is adjustable to the desired heat.
Four burner stove represents the case in the form of a desktop with four burners. Inside the case there is an oven for frying and baking culinary and bakery products. Under each burner there is an upper burner, and under the bottom of the oven there are two tubular burners. The upper burners have a separate faucet, and the tubular lower burners have one common faucet with a handle. All faucets are connected to the gas distribution pipeline through which gas flows.
The plate has the following dimensions: length 925 mm, width 565 mm, height 810 mm. Oven dimensions: length 490 mm, width 360 mm, height 230 mm. Burner diameter 200 mm.
Combined gas stove equipped with two burners and a solid frying surface. Two through ovens are heated by two tubular burners located below them. The solid frying surface has six cast-iron hotplates, with holes in the center. The openings are closed with lids. Each burner is heated by an open gas burner, and each cast-iron tile by three slot burners.
Gas burners are located on both sides, so it can also be operated from two sides.
The plate has the following dimensions: length 2220 mm, width 1455 mm, height 830 mm.
Special attention should be paid to gas devices in production. Any gas leak can cause an explosion and also cause poisoning of workers. All personnel must be instructed in the use of gas equipment and comply with all safety requirements.
fire plate
These boards are produced in different sizes: board No. 1 has a heat-resistant surface of 4.5 m2, board No. 21 - 2.04 m2, board No. 19-0.9 m2 and board No. 2 - 0.45 m2.Fire stoves can work on wood and on fuel oil.
When working on wood, the grate should be cleaned of ash before operation, since the grate is quickly clogged with ash and fine coals. As a result, the air is poorly supplied, and the combustion process is difficult.
Firewood should be selected in size: in length and thickness. Firewood must be stacked tightly to each other. In the process of burning, firewood should be stirred so that the firewood burns out at the same time, and so that there is no accumulation of unburned logs. A new portion of firewood is loaded after the first layer burns out. During kindling, the valve (gate) is opened completely, and after the firewood flares up, it is closed. In the process of combustion, the valve is either closed or slightly opened, thereby regulating the combustion process.
Furnace doors should be closed so that the incoming air does not cool the furnace. Furnace doors are opened for throwing firewood or mixing it.
When using oil stoves, it is necessary to monitor the timely supply of liquid fuel - fuel oil to the nozzles by special pumps or by gravity from a pressure tank. In addition, the supply of steam or air to the nozzles (in steam or air nozzles) is important.
Barbecue ovens. Barbecue ovens, as well as hearths and barbecues, are used for frying shish kebabs, kupats, meat fillets, sturgeon and other culinary products. They are made of bricks on an iron frame.
For frying kebabs, mechanical devices are used to rotate the skewers so that the meat is evenly fried on all sides.
digester
The electric digester is designed for cooking soups, cabbage soup, broths, cereal side dishes, cereals, vegetables. The advantage of using an electric kettle is that the food in it cannot burn, and this is very important for cereals, kissels, boiling milk, stewing, etc. The digester consists of double-walled cylindrical vessels, external and internal. Between the walls of the vessels there is a space called a shirt, which is filled with water. The water is heated by an electric heater.
In public catering establishments, cooking boilers with a capacity of 20 to 250 liters are used.
The inner vessels and lids are made of stainless steel. The outer walls are covered with a layer of thermal insulation. The lids are hinged and equipped with counterweights. When closed, the lids are tightly screwed with hinged bolts.
Before starting to load the boiler with products, water is filled into the jacket, the maximum heating is turned on. After 10-15 minutes, the boiler is filled with products. After some time, as the products are ready, the heat is reduced, and then completely turned off.
Both steam and gas boilers are used in catering establishments. Their device is the same as that of electric ones. The steam room is heated by steam, which is supplied through pipes from the boiler room.
Boilers are available with a capacity of 125 and 250 liters. The power consumed by the boiler depends on the capacity and ranges from 4 to 32 kW.
Tilting saucepans
Sauces, garnishes, kissels, etc. are prepared in these boilers. But having a large set of containers, they allow you to cook several dishes at the same time.Tilting boilers are installed on separate racks and have a tilting mechanism, this allows you to significantly speed up and facilitate the process of releasing the boiler from the finished product.
Gravy boilers are produced with a capacity of 20, 40, 60 liters. They are equipped with safety fittings and have removable covers. The power of the boilers is from 2.5 to 9 kW.
Plate autoclave
A plate autoclave is used for boiling bones, boiling broths, vegetables, cereals, etc.
The pressure cooker cooks food at elevated pressure and at a high boiling point. The boiler is closed with a hermetic lid. Bones, previously freed from meat, are cooked in such boilers to speed up the cooking process. Cooking in an autoclave allows a more complete extraction of fat and adhesive substances from the bones.
Inside the autoclave there is a lattice vessel, into which bones are loaded, previously boiled in an ordinary boiler, then the product is poured with water; the water level should be above the level of the bones. The prepared autoclave is closed with a lid with hinged bolts.
The autoclave is equipped with a pressure gauge showing the steam pressure inside the boiler and a spring-type safety valve that automatically releases steam at increased pressure. This valve can also regulate the steam pressure inside the autoclave.
The autoclave is an object of increased danger, it is regularly checked by the boiler supervision authorities.
Tilting electric frying pan
The electric frying pan is used for frying pancakes, cutlets, donuts, pies, stewing and frying meat and vegetables. The frying pan is a cast-iron bowl with a closed removable lid, mounted on a mounted fork-shaped stand.
At the bottom of the bowl there is an electric heating element, the power of which is regulated by a switch. The walls of the pan are covered with thermal insulation.
Before cooking the product, the electric frying pan heats up at full power, then switches to the desired temperature mode, depending on the requirements of the product. The product can load after 25-30 minutes of warming up.
Within an hour, up to 10 kg of potatoes or up to 200 meat cutlets, or up to 400 donuts and pies in oil can be fried in an electric frying pan.
The diameter of the loading bowl is about 50 cm, its depth is 14 cm, and the capacity is 30 liters. Power consumption at the highest degree of heating 5 kW.
Electric fryer
The electric fryer cooks donuts, pies, potatoes and other culinary products in oil.The product is placed in a mesh basket and placed in an oil bath. The electric heaters are installed so that the top of the oil is hot and the bottom is cold. This is done so that small particles and crumbs getting into the bottom of the bath do not burn.
Drain the used oil through a special pipe. In an electric fryer, you can cook up to 750 donuts or up to 600 pies within an hour.
The maximum power consumption is about 5 kW.
Electric coffee maker
The electric coffee maker is a cylindrical vessel with a capacity of 9.5 liters. A device for circulating boiling water and supplying it to the filter is installed at the bottom. This device consists of a steam cap and a circulation tube, on the upper end of which a filter is put on, which is an aluminum bowl with a perforated bottom with a large number of holes. To make coffee, pour water into the vessel up to 7 liters (less than 4 liters is not recommended), close the lid and turn on the first degree of heating. Ground coffee is poured onto the filter 5 minutes before the water boils. After heating the water, the steam rushes up the circulation tube and carries with it the boiling water, which irrigates the coffee on the filter. After passing through the layer of coffee, the water returns back to the vessel. Immediately after the start of brewing, the heating element switches to the lowest degree of heating, and after the end of brewing, it turns off automatically.
As a result, coffee is brewed. The process takes 5-7 minutes. Coffee is served 4-5 minutes after the coffee maker is turned off. The heating of the cooled coffee is carried out at a low temperature.
After finishing work, the electric coffee maker should be disconnected from the mains, remove the filter and the device for water circulation, rinse well and dry. The vessel also needs to be washed.
The housing of the electric cooker must be grounded.
Electric oven and pastry cabinet
In this cabinet, confectionery and piece bakery products are baked, as well as fried and baked culinary products.
The oven and confectionery cabinet has two independent chambers installed one above the other. The industry also produces single-chamber and three-chamber ovens.
Electric heating elements are installed in each chamber at the top and bottom. There is a heating thermostat that automatically maintains the set temperature in the range from 100 to 350 °.
Each chamber consumes 4.5 kW of power. Cabinet warm-up time to maximum temperature (350°) 1 hour 20 minutes.
Within an hour, 300 - 350 sourdough buns can be baked in the cupboard or 25-30 kg of potatoes can be fried.
The table shows the duration of cooking and the recommended temperature for various dishes and products:
Food warmers
Food warmers are designed to keep ready meals, side dishes and sauces hot. Bain-maries are installed in distributing rooms. There are food warmers for first and second courses.
Electric food warmer for first courses. The food warmer electric stove is a rectangular cast-iron burner with a surface of 0.15 m2. An electric heating element is mounted inside the burner.
The switch allows you to adjust the degree of heating of the burner. Food for heating is placed directly on the burner.
The power consumption of the plate is 2.5 kW. Plate size: height 500 mm, length 600 mm, width 600 mm.
Bain-marie for second courses. These food warmers can be heated by electricity or steam.
An electric food warmer is a counter, in the upper part of which there is a hot water bath covered with a metal sheet. There are holes in the metal sheet into which pans with removable lids are immersed. Main dishes, sauces and side dishes are heated in food warmers.
Maximum power 3.8 kW.
The simplest food warmer- This is a large baking sheet with high sides and handles. Hot water is poured into a baking sheet, and special dishes (bain-marie) with ready-made hot food are immersed in it. The food warmer is installed on the heated frying surface of the stove.
Plate warming racks
In dispensing rooms, special heat racks are used to heat plates and keep food hot.The electric rack is a table with a cabinet. The cabinet and the table top are made of stainless steel and are heated by electric heaters, which are located at the bottom of the cabinet under the removable grids and under the rack cover.
The maximum power of the electric rack is 3 kW.
Boilers and dishwashers
Boilers
Boiling water should always be available in catering establishments. For this, continuous boilers are installed. The operation of such special devices is based on the continuous flow of water from the water supply to the lower reservoir. Immediately after boiling water, you can use boiling water, while the water will be automatically replenished.
Continuous boilers can run on electricity, gas, solid fuels (wood, coal). The arrangement of boilers for all types of fuel is similar.
The electric boiler is a cylindrical column with a chrome-plated surface. First, water comes from the water supply, passes through a valve with a float device and a supply box, then enters a vessel for boiling water. The float device automatically regulates the flow of water and ensures a constant water level in the feed box.
The water is heated by tubular elements that are installed in the water vessel.
The performance of the electric boiler is 75-80 liters per hour. Boiling time of water is 15-20 minutes. Power consumption 10.5 kW. Solid fuel boilers have a capacity of 200 to 600 liters per hour.
Dishwashers
In large catering establishments, a conveyor dishwasher with a capacity of 2-2.5 thousand plates per hour is used.
This machine is a cabinet with lifting doors. Washing showers are located at the top and bottom of the cabinet. At the bottom there is a bath for used water, a centrifugal pump and an electric motor.
The water is heated in the bath by means of tubular electric heating elements up to 60°C and is supplied by a centrifugal pump to the washing showers.
After washing, the dishes are rinsed with showers with hot water heated to 95 °. Water for these showers comes from a special heater, which is located separately from the machine.
Dirty water drains through the pan into the bath, and leaves it through the overflow pipe into the sewer.
Before loading into the dishwasher, remove food residues from the plates, then place them on edge on wooden trays.
The conveyor chain continuously feeds trays with plates to the washing chamber, where they fall first under the washing and then rinsing showers. Trays with clean dishes are placed on a separate table.
Glasses and cutlery are washed like plates, but they are placed in trays with a mesh bottom.
In small enterprises, dishwashers of a simpler type are installed, their productivity is 500-600 plates per hour. Such machines are intermittent units, they do not have conveyor loading of dishes. Loading dishes into machines and unloading clean dishes is done manually.
Rinsing dishes is done with boiling water, so it dries quickly, and it is not wiped with a towel.
Refrigeration equipment
Refrigeration equipment can be of the following types: refrigerated cabinets, collapsible refrigerating chambers and refrigerated counters of machine cooling.Refrigerators
Refrigerated cabinets at ambient temperatures up to 30° provide storage of products at a temperature of 0 to 6°.
The temperature inside the cabinet is automatically maintained by a freon refrigeration machine powered by an electric motor.
The walls of the cabinet have double metal sheathing, between which there are thermal and anti-moisture insulation. The doors are sealed with an elastic band and equipped with self-locking latches. Inside the cabinet there are shelves for storing food and ready meals.
When arranging the products, it is necessary to leave a gap between them so that there is air circulation. Inside the cabinet there is an electric light.
Cases happen four and six doors. Useful area of cabinets from 0.5 to 1.5 m2.
Collapsible refrigerating chamber
Perishable products weighing up to 600 kg can be stored in this chamber. The chamber requires a floor area of 3.2 m2. The internal volume of the chamber is 7.4 m3.The chamber is built of six separate wooden shields fastened together. Between the shields there is thermal and dampproof insulation. The door is sealed with an elastic band and equipped with a lock. Inside the chamber there are lattice shelves for products and hangers.
The temperature inside the chamber is from 0 to -2°, at an ambient temperature of up to 25°, it is automatically maintained by a freon refrigeration machine.
Low temperature counter
The low-temperature counter is used to store ice cream, frozen fruits, berries, vegetables, fish at temperatures from -12° to -16°. The counter is made of wood and sheathed with double metal sheathing, between which there is thermal and anti-moisture insulation. The chamber consists of three sections for loading products. Each opening is closed with a removable cover and a rubber seal.
Cooling is carried out by an automatic freon refrigeration machine, powered by an electric motor, which is located outside the counter.
Products should be laid at intervals of 1.5 - 2 cm so that air circulation occurs.
Counter capacity 0.4 m3, available capacity up to 150 kg.
Installation for the mechanical production of ice cream (freezer)
The body of the installation consists of two parts - the engine room and the hardening chamber.The engine room has a freon refrigeration machine and a drive with an electric motor that drives the sleeve and agitator blades.
The hardening chamber consists of a freezing sleeve and a collection tank sleeve. The central and lateral stirrers are mounted in the freezing sleeve. The liner body and blades rotate in opposite directions. Around the freezing sleeve there is a tubular coil - a cooling device.
The ice cream mixture fills the sleeve and closes the lid, after which the electric motor turns on and the sleeve and blades begin to rotate.
Ice cream is prepared at temperatures up to –15–20°C with continuous mixing of the mixture.
The finished mass for ice cream is frozen in a jar to a semi-solid state with the help of an ice-salt mixture, which is wrapped around the jar. The jar is placed in a wooden tub, which is then filled with an ice-salt mixture (pieces of ice sprinkled with salt).
The rotation of the can is carried out using a mechanical or manual drive.
Manual ice cream makers have a useful capacity of a can of 9 - 12 liters. Their productivity is 12 - 15 kg of ice cream per hour.
The drive ice cream maker has a can capacity of 50 liters. Duration of freezing of one loading 25 - 30 minutes.
When filling the space between the jar and the walls of the tub with ice sprinkled with salt, up to 200 g of salt is taken per 1 kg of ice. The ice must be very finely chopped, the freezing process depends on this. The smaller the ice, the faster the process. Salt should be poured as evenly as possible.
Melt water from the tub should be poured out every 5-10 minutes, and the loss of ice should be replenished with new pieces of ice, sprinkling them with salt. At the end of work, the remains of ice and salt should be removed, the insides should be rinsed well. Banks and spatulas should be washed with hot water.
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Thermal equipment is designed for thermal processing of products for the purpose of cooking. It includes a wide variety of models: stoves, boilers, ovens, frying pans, grills, food warmers, thermoses, combi steamers, combi steamers and many others. Consider the main types of thermal equipment.
Plates. Plates - the universal equipment intended for implementation of various types of thermal processing of products. When choosing stoves, many factors should be taken into account, including the size of the equipment, power, the presence of an oven, the type of burners, and the price.
Cookers used in food establishments can be classified:
By type of heating (electric, gas, induction);
by size (stove accessories for various series of heating equipment);
heating surface material (steel, cast iron, glass-ceramic);
coating of non-working surfaces (various types of steel).
Standard series of heating equipment differ in the distance from the front panel to the back wall of the stove or depth. The most common are the 700 and 900 series, less common are the 1100 plates (the numbers indicate the distance in millimeters), the so-called Olympic series, designed for large catering establishments with high traffic.
Each type of heating has its own advantages and disadvantages. disadvantage electrical cast-iron plates is their inertia, which consists in a sufficiently long period of heating and cooling of the surface, and, as a result, a large consumption of electricity. In addition to traditional electric stoves with cast iron burners, there are electric stoves with a glass-ceramic surface on the market - the stove heats up and cools down much faster. The use of glass ceramic makes it easier to sanitize stoves and clean work surfaces, but careless handling can leave scratches. Only high-quality stainless steel pans and pots with a heavy and slightly concave bottom should be used on such stoves.
Gas plates (Fig. 69) it is recommended to install only in cases where the installation of electric stoves is not possible for any reason. Along with the undoubted advantages of gas equipment: efficiency, ease of use, lack of inertia, there are a number of disadvantages, including toxicity, explosiveness. When installing gas stoves, first of all, you will need effective exhaust and supply ventilation. Gas stoves are offered in two versions - with open burners and with a solid cast-iron surface.
Rice. 69. Gas stove
AT induction slabs (Fig. 70) due to the created eddy currents, it is not the surface of the stove that is heated, but the special dishes standing on the stove. At the same time, there is no loss of heat to the environment, which allows to reduce energy consumption by 40% compared to electric stoves and at least 70% to reduce the time for heating dishes to the temperature required for cooking. Heating and cooling are very fast. The price of such plates is higher and special metal utensils are needed.
Rice. 70. Induction cooker
All listed plates can be both floor and desktop. Table cookers are installed on tables and are convenient for use in establishments with small kitchens. Floor plates are intended for canteens, restaurants, etc. of average and high productivity.
Proper operation, proper care and timely service are the three components of reliable and trouble-free operation of stoves of all types of stoves.
Frying surfaces designed for heat treatment of meat, fish or vegetables directly on the heated surface (Fig. 71). They are made of steel or cast iron and, depending on the modification, are smooth or corrugated. There are also combined options: one part of the surface is smooth and the other is corrugated. As a rule, frying surfaces are equipped with thermostats. Models are desktop and floor. They differ in their dimensions. The series indicates the length of the frying surface in mm, for example, 400, 600, etc. (as with stoves). The advantage is lower oil consumption compared to stoves.
Rice. 71. Frying surface
Boilers. For boiling large volumes of water and long-term boiling of products, steam boilers are used. (Fig. 72). Of course, the same operations can be performed on stove-top cookware, but at a slower pace and with more energy. The design of the boiler, where the steam-water jacket with built-in heating elements effectively transfers the heat of the heated liquid, and the tight-fitting lid protects against heat loss from above, makes it possible to repeatedly intensify the conversion of electrical energy into thermal energy, but the boiler costs about twice as much as a conventional stove, therefore it is not used at every public enterprise. nutrition. The model range contains a wide variety of boilers with volumes from 50 to 250 liters.
Rice. 72. Steam boiler
The standard equipment includes taps for supplying hot and cold water to the boiler, an overflow pipe on the working surface for draining water during washing and a filling funnel in the steam jacket. Some manufacturers have improved the design of the boiler in such a way that water is poured into the jacket once every few years. Manufacturers use only stainless steel as a structural material.
The design of the boiler may provide additional functions and devices:
· Tipping mechanism. The presence of this function will reduce the time for emptying the boiler and sanitizing at the end of the work shift.
· A steam faucet that freely passes the cut ingredients of first courses in a standard way.
· A mechanism that carefully grinds and stirs the products inside the boiler.
· The hermetically closed cover of a copper by means of the locking mechanism. The lid can also withstand overpressure. Such an apparatus is called an autoclave and can be used for accelerated heat treatment of raw materials in water or steam at temperatures above 100 ° C.
· Two separate groups of heating elements - for heating the bottom and walls.
Fryers designed for frying foods (fries, chicken, vegetables, meat, etc.) (Fig. 73). Fast frying allows you to maintain sufficient moisture and the natural taste of the cooked dish.
Rice. 73. Fryer
The fryer is a bath with built-in heating elements, temperature sensors and a control panel. The recommended loading ratio of product to oil volume is 1:4. Technological cards for deep-fried dishes emphasize that the product must be dried, otherwise the cooking time increases to 40%, which is required to heat up and evaporate the water that has got into the deep-fryer. In one bath, it is better to fry homogeneous products. For example, for this reason, it is better to purchase a twin fryer of 4 liters than one with a volume of 8 liters. When choosing fryers, it is advisable to check the availability of protective equipment that guarantees safe operation: a dry-running protection sensor and an emergency oil overheating sensor.
The design of a pasta cooker is very similar to a deep fryer, only water is used instead of oil. They can be used for cooking dumplings, cereals and vegetables.
Grills. There are a large number of different grills: lava grill, contact grill, roller and carousel grill, pizza grill, shawarma grill, etc. Initially, the grill meant a heat treatment process that excluded contact of the product with the heated surface. The word came into Russian from the French griller, which means to burn. In the future, the range of equipment with the name grill expanded significantly and included equipment that provides for the contact of the product with a heated surface. Consider some types of grills.
lava grill imitates hot charcoal in the grill (Fig. 74). The gas burner red-hot pieces of lava, and they, due to their porous structure, serve as a source of intense thermal radiation.
Rotary grills. The main purpose of such grills is roasting chickens, but you can cook meat, fish and vegetables in this way. (Fig. 75). The continuously rotating grill is able to cook the product in the so-called pulse heating mode. Rotating around a stationary heat source, the product receives portions of thermal energy not constant, as in a frying pan or in an oven, but of variable intensity. This mode is able to provide a beautiful uniform roast.
Rice. 74. Lava grill 75. Rotary grill
Grills that provide contact with the work surface. Contact or conductive grills are widely used, which have two heating surfaces - top and bottom (smooth or corrugated) (Fig. 76). The corrugated surface allows you to get stripes on the finished product, giving it a more attractive look. However, the embossed surface will require more oil consumption and extra cleaning time.
Rice. Fig. 76. Contact (conductive) grill. 77. Salamander Grill
Grill "salamander" designed in such a way that heat is distributed to the grate from above (Fig. 77). The degree of heating intensity is regulated by the distance between the movable upper part with the heating element and the fixed lower part with the processed product.
Grill "shawarma" characterized by a vertical arrangement of a rotating skewer (Fig. 78). The same position is occupied by infrared heating elements or specially adapted gas burners.
Gas grill. The long gas burner is covered on top by a massive stainless steel semi-cylinder (Fig. 79). Above it is a height-adjustable grate with food, and below it is a container with water, which increases humidity and serves to instantly cool the released fat and eliminate unpleasant odors. The ability to adjust the distance between the heating elements and the product makes it possible to select the optimal heat treatment mode.
Rice. 78. Shawarma grill 79. Gas grill
combi steamers designed for baking bakery products (fig. 80). They use the effect of forced circulation of heated air. They use special heating elements to heat the air, and a fan built into the chamber creates a constant movement (convection) of hot air. Baking trays are located in the ovens. Combi steamers usually have two control knobs for temperature and time control.
Rice. 80. Combi oven
Combi steamers designed for cooking gastronomic dishes (Fig. 81). In steam convection ovens, air, together with the generated steam, circulates throughout the chamber at high speed, which ensures the same temperature throughout the chamber and the uniformity of food preparation. As a result, meals are prepared quickly, there is less loss of vitamins and mineral salts, and less weight loss of the product compared to the traditional way of cooking. Saves water, electricity and space.
There are three main cooking modes used in combi steamers:
Steam mode
convection mode;
combined mode (steam and convection).
Steam mode guarantees an even cooking process, ideal for stewing, steaming, soaking. The convection mode is suitable for frying, baking, grilling. Combination mode prevents food from drying out, reduces weight loss and achieves even browning.
More complex models may have additional features: defrosting, regeneration (for heating dishes), wetting, automatic core temperature (cooking with particular accuracy using a special probe with a temperature sensor placed inside the product).
Combi steamers usually differ in the way of steam formation: in some, the so-called injection water is injected, which, falling on the heating elements, quickly evaporates, forming steam, in others, steam generators (boilers), a special boiler is installed, from where steam enters the working chamber.
According to the degree of automation, we can distinguish: non-programmable and programmable devices. The latter are convenient with a constant menu, when the same dishes are prepared many times. The user sets the cooking method, time, temperature data once, and then only calls them up through the program number.
Rice. 81. Combi steamer
microwaves(Fig. 82). The principle of cooking with microwaves is fundamentally different from conventional heating methods. The magnetron converts electrical energy into microwave energy, which activates the water molecules, and they vibrate at a frequency of about 20 billion times per second, collisions between them lead to the formation of heat that heats the product. Microwaves are reflected by metal surfaces, but they pass through paper, glass, ceramics, porcelain, plastic, wood, etc. Therefore, metal utensils cannot be used. Advantages of microwave ovens over traditional cooking methods:
Requires less time, water, fats, salt;
more vitamins and minerals are preserved;
The stove does not create a typical kitchen atmosphere in the room with stuffiness, heat and corresponding odors;
· high efficiency: almost all electricity goes to cooking, not heating the kitchen.
Mechanical, touch and electronic push-button control are possible. Mechanical - the simplest and most reliable: it is enough to set the radiation level and the operating time (timer) with two rotating handles. Touch control makes it possible to automatically evaluate and set the time required for the preparation of the product. Some models of microwave ovens have a steam sensor that is programmed and provides accurate results. When the products begin to release steam, it means that the temperature has reached 100 ° C and only from this moment the required cooking time is determined. On the control panel, you can pre-program the operation for the execution of complex recipes. Many models have built-in cooking recipes.
Rice. 82. Microwave
Food warmers(Fig. 83). The purpose of this type of heating equipment is to provide temperature regimes approved by sanitary rules for short-term storage of ready meals in a heated state. SanPiN 2.3.6.959-00 regulates the requirements for the distribution of dishes as follows: “Hot dishes (soups, sauces, drinks) during distribution must have a temperature of at least 75 ° C, main courses and side dishes - at least 65 ° C.
The designs of food warmers used for the soft heating method can be as follows:
· Steam food warmer, where products in gastronorm containers are 3-5 cm from the water, heated by heating elements to a temperature of 80-85 ° C.
· Dry bain-marie, the bottoms of gastroyemkost are warmed up by the heating element designed for work in the air environment.
· Glass-ceramic food warmer.
· Infrared food warmer, where, as a rule, the source of thermal radiation, made in the form of a special lamp or tube made of quartz glass, is located above the heated product.
· Combined food warmer, where a combination of the above methods is used.
Food warmers can be stationary and mobile.
Rice. 83. Food warmers
Food transport equipment. Depending on the distance to the place of distribution, either transport trays or thermal pans and thermal buckets are used, and for a large number of transported dishes - large plastic thermal containers. Permissible temperature changes of 1.5°C per hour when transporting a hot dish. At banquets, when serving complex dinners, a tray and a plate are used that keep the temperature, which are made according to the principle of a thermos: double metal, vacuum inside.
Rice. 84. Thermal showcase
Apparatus for preparing certain dishes. These include: pancake, cutlet, donut machines, toasters, coffee machines, etc.
Pans and pots. Catering establishments use professional utensils, which, unlike household ones, have some features:
For professional tableware, appearance is not very important, but ease of use and functionality are important;
· special requirements to the places of attachment and forms of handles of professional utensils, which must be durable and reliable in conditions of intensive use.
In the manufacture of dishes, various materials are used.
Cast iron- high-carbon steel has very good heat-conducting properties; in the process of frying food, a fried crust is formed, which prevents the evaporation of juices and aromas, keeping them inside. But since cast iron is a porous material, it is able to retain odors and microscopic food particles, which violates the taste of dishes.
Steel pans are good for frying, have excellent hygienic properties, good thermal conductivity.
Copper - very expensive material, has excellent thermal conductivity. However, direct contact of copper with products is not recommended, so it is made either tinned (tinned on the inside, or with a stainless steel interior).
Aluminum banned in many countries, since it causes rapid oxidation and souring and the formation of carcinogenic substances upon contact with products, but can be used when creating multilayer cookware as one of the layers or as a base (body) on which a non-stick coating is applied. This coating can be easily washed and is used for the preparation of delicate products. When frying in such a dish, a fried crust on the prepared dish is not obtained. It is necessary not to mechanically damage this coating, so it must be handled with care. Some cookware uses sandwich bottom manufacturing techniques (distribution bottom). Usually it has a three-layer structure (two layers of stainless steel, between them a thick layer of aluminum, which conducts heat better than steel). There is a risk of thermal shock, which can cause the bottom to separate if an empty pan is placed on the heating surface.
One of the latest inventions amalgam(an alloy of several grades of stainless steel), which conducts heat very well. It is monolithic, which eliminates the stratification of the bottom and preserves the taste of the products.
For the manufacture of confectionery products, special molds are used, made of silicone or foamed silicone. The structure of the material contains air bubbles. It is 100% non-stick, can be used without oil, but does not give a fried crust. The form from these materials cannot be put empty on a heating surface.
Thus, there are a large number of models of equipment for the preparation of various dishes that perform any task. Their performance characteristics depend on the device, the principles of operation and the materials from which they are made.
The scientific and technological progress of modern food industry production has made great changes in the methods of heat treatment of culinary products of catering establishments. Along with traditional surface (conductive) methods of cooking, volumetric methods of heat treatment of products are widely used.
Volumetric heating methods are based on the interaction of the product with an electromagnetic field. Electromagnetic energy from the radiation generator, turning into heat, penetrates into the mass of the product to a considerable depth and in a very short period of time ensures its heating to the finished state.
Surface methods of cooking food products for technological purposes are classified into cooking, frying, frying-baking, water-heating and auxiliary. Cooking equipment includes:
cooking kettles, the technological medium of which is water or broth at a temperature of 100 ° C;
autoclaves in which heat treatment is carried out with steam at a temperature of 135 ... 140 ° C;
steamers, in which the technological process of cooking is carried out with steam at a temperature of 105 ... 107 ° C;
vacuum apparatus, the working medium of which is heating steam at a temperature of 140 ... 150 ° C.
The group of frying equipment includes:
frying pans in which the frying operation is carried out in a small amount of fat at a temperature of 180 ... 190 ° C;
fryers, the frying process in which takes place in fat at a temperature of 160 ... 190 ° C;
ovens (grills, barbecue ovens) that carry out the process of cooking products in hot air at a temperature of 150 ... 300 ° C.
The frying and baking equipment includes: ovens, ovens and baking cabinets, in which the technological medium is hot air at a temperature of 150 ... 300 ° C;
steam fryers, the working medium of which is a mixture of hot air and superheated steam at a temperature of 150 ... 300 ° C.
Water heating equipment is represented by boilers and water heaters.
Auxiliary equipment includes food warmers, heating cabinets and racks, thermostats, equipment for transporting food.
Volumetric methods of heat treatment of products are carried out: in microwave cabinets of periodic and continuous action; microwave method provides a high heating rate of products;
IR devices; infrared heating is based on the intense absorption of infrared radiation by free water in the products;
EC-heating devices; electrocontact heating is based on the thermal energy released by the current for a certain time when it passes through a product with a certain active (ohmic) electrical resistance;
induction heating installations; induction heating of food products, especially with high humidity, occurs when they are placed in an external alternating magnetic field, in which, according to the law of electromagnetic induction, eddy currents (Foucault currents) occur, the lines of which are closed in the thickness of the product, electromagnetic energy is dissipated in its volume, causing heating .
The main advantage of the microwave is the speed of heating food products.
However, this method of heating also has disadvantages - the absence of a crust on the surface of the product and, as a rule, the natural color of the raw material.
Positive indicators of IR heating are uniform color and thickness of toasting.
However, this method has disadvantages:
not all products can be subjected to IR heating;
at a high flux density of IR radiation, a “burn” of the product is possible.
EC heating is used as an independent type of treatment, and in combination with other methods. In particular, it is successfully used in the bakery industry to warm up the dough mass when baking bread, in the production of sausages, and in blanching meat products.
The induction heating method is not yet widely used in catering, but it has significant economic opportunities for successful use in the future.
Taking into account the fact that surface and volumetric methods of heat treatment of food products, along with advantages, also have disadvantages, it is advisable to use them in combination in the production of public catering.
