2. A system as claimed in claim 1 comprising a unit for controlling the process of vacuum cooling and dehydration of foodstuffs by driving the actuating mechanism and producing a vacuum in the chamber connected to said circuit for prescribing the program of vacuum cooling and dehydration, said control unit and said circuit for prescribing the program of vacuum cooling and dehydration including a feedback means, the control unit being connected to the actuating mechanism for eliminating the vacuum.

3. A system as claimed in claim 1 wherein said control unit comprises a unit for selection of the operating conditions of the chamber and for starting the system connected to and controlling the actuating mechanism connecting the chamber with the atmosphere, a unit for regulation of the steam supply for putting into operation said unit controlling the temperature of boiling the foodstuffs connected with said unit for selection of the operating conditions and for starting the system; a unit to control said actuating mechanism for draining off the condensate from the chamber connected to said unit for controlling the steam supply and operated thereby and to the unit for controlling the actuating mechanism connecting the chamber with the atmosphere and setting the latter to the initial condition in the duty with an excessive pressure in the chamber built up by the heating steam, and connected to said circuit for prescribing the program of vacuum cooling and dehydration to put the latter circuit into operation; a unit for controlling said mechanism eliminating the vacuum after creating a vacuum according to a predetermined cooling program, said unit for controlling said mechanism being connected to said circuit for prescribing the program of vacuum cooling and dehydration; a unit indicating the commencement and end of the process of boiling, vacuum cooling and dehydration connected to said unit for selection of the operating conditions and for starting the system and to said circuit for prescribing the program of vacuum cooling and dehydration.

4. A system as claimed in claim 3 wherein said unit for selection of the operating conditions of the technological apparatus and for starting the system comprises a starting element connected with said power supply unit and commutating elements connected with said starting element.

5. A system as claimed in claim 4, wherein said unit indicating the commencement and end of the process of boiling, vacuum cooling and dehydration comprises a signalling element, a pneumoelectric transducer of the signal connected to said starting element and indicating the commencement and end of the process of boiling and cooling, a means for adjusting the duration of the control signal controlling said signalling element and connected to said unit for prescribing the program of cooling and a valve for feeding said means for adjusting the duration of the control signal.

6. A system as claimed in claim 3 wherein said unit for controlling the actuating mechanism connecting the chamber with the atmosphere comprises a control circuit operating in the duty with an excessive pressure; a control circuIt operating in the duty without an excessive pressure; an ''''OR'''' element whose inputs are connected to said control circuits; and a control signal power amplifier connected to said '''' OR'''' element.

7. A system as claimed in claim 6, wherein said control circuit operating in the duty without an excessive pressure comprises a memory cell for storing the signal which operates the actuating mechanism connecting the chamber with the atmosphere, said memory cell being connected to a corresponding commutating element of said unit for selection of the operating conditions and for starting the system.

8. A system as claimed in claim 6, wherein said control circuit operating in the duty without an excessive pressure comprises in combination: a memory cell for storing the signal operating the actuating mechanism for communication of the chamber with the atmosphere, said memory cell being connected to a corresponding commutating element of said unit for selection of the operating conditions and for starting the unit, and a means for adjusting the duration of the operating time of the actuating mechanism connected to and erasing the signal in said memory cell.

9. A system as claimed in claim 3 wherein said unit for controlling the steam supply comprises a memory cell for storing the signal operating said unit for controlling the temperature and connected to said starting element; time-delay relay; a pneumoelectric transducer for switching on said time-delay relay connected to said memory cell; an electropneumatic transducer for erasing the signal in said memory cell, said transducer being connected to said memory cell and to said time-delay relay.

10. A system as claimed in claim 9 wherein said unit controlling the actuating mechanism for draining off the condensate comprises in combination: a memory cell for storing the signal controlling the operation of said actuating mechanism connected to said electropneumatic transducer; means for adjusting the operating time of said actuating mechanism and for erasing the memory of the considered control unit and of the control circuit in the duty without an excessive pressure; a control signal power amplifier operating said actuating mechanism, the input of the power amplifier being connected to the output of the memory cell of the considered control unit.

11. A system as claimed in claim 3 wherein said unit for controlling the actuating mechanism for eliminating the vacuum comprises a means for adjusting the operating time of said actuating mechanism after setting the vacuum, said means for adjusting the operating time being connected to said circuit for prescribing the program of vacuum cooling and dehydration, a valve for feeding said means for adjusting the operating time, a signal-power amplifier to operate said actuating mechanism for eliminating the vacuum in the chamber connected to said means for adjusting the operating time.

12. A system as claimed in claim 1 wherein the circuit for prescribing the program of vacuum cooling and dehydration comprises in combination: a unit for preparing the circuit for operation, a timing unit for coding switching signals in a binary code connected to said preparing unit, a decoder of the output signals of the timing unit, a unit of pulse shapers for adjusting the time delay of the signals fed from said decoder, a signal commutator commutating the signals of said pulse shapers, a starting unit connected to said unit of pulse shapers, a unit for prescribing the rate of setting linear sections of the program of vacuum cooling and dehydration connected to said decoder and to said commutator, a unit for prescribing the threshold of the linear sections of the program of vacuum cooling and dehydration connected to said decoder, a unit for presetting the time constant of exponential sections of the program of vacuum cooling and dehydration connected to said decoder, a unit for presetting the asymptote of the exponential sections of the program of vacuum cooling and dehydration connected to said decoder and to the unit for presetting the time constant, and an output unit for switching the circuit components and for power amplification of the output signal connected to said decoder to the units for prescribing the rate of setting and threshold of the linear sections and to the units for presetting the time constant and asymptotes of the exponential sections.

13. A system as claimed in claim 12 wherein the preparing unit comprises valves for passing a ready-down signal and a starting element connected to said valves.

14. A system as claimed in claim 13, wherein the unit for prescribing the rate of setting the linear sections comprises valves for preparing this unit for operation, a cell for prescribing the rate of setting, a constant drop cell for the provision of a continuous supply of said cell for prescribing the rate of setting, and variable capacitors for accurately trimming the rate of setting the linear sections.

15. A system as claimed in claim 13, wherein said unit for prescribing the threshold of the linear sections comprises a cell for setting the values of the thresholds and valves for producing the signal for shaping the linear sections.

16. A system as claimed in claim 13, wherein said unit for presetting the time constant of the exponential sections comprises valves for preparing said unit for operation, inertia cells and valves for producing the signal for shaping the necessary exponential signal.

17. A system as claimed in claim 13, wherein the unit for presetting the asymptotes of the exponential sections comprises cells for setting the values of the asymptotes and valves for shaping the signal.

18. A system as claimed in claim 13, wherein said unit for switching the circuit components and for power amplification of the output signal comprises in combination: a comparison element transferring the program from the shaping of the linear sections to the shaping of the exponential sections, a first accumulator for continuously adding the signals corresponding to the threshold of the linear sections and to their current values, a second accumulator for adding the signals corresponding to the threshold of the linear section and to the asymptote of the exponential section, a comparison element whose input is connected to the second accumulator and whose output is connected to said timing unit, a switch connected to said unit for prescribing the rate of setting the linear sections to the comparison element and to the first accumulator, and a control signal power amplifier connected to said switch, said comparison elements and power amplifier being provided with a feedback circuit.

19. A system as claimed in claim 12 wherein said timing unit comprises memory cells.

20. A system as claimed in claim 12, wherein the commutator comprises ''''OR'''' elements.

21. A system as claimed in claim 12, wherein said starting unit comprises a memory cell for storing a triggering pulse and a pulse shaper for erasing the signal in said memory cell.

22. A system as claimed in claim 12 wherein the decoder comprises an inverter for conversion of a single-shot input signal into a zero signal and a zero signal into a single-shot input signal, and values for passing command signals.