GB754510A - Improvements in and relating to the preparation of food - Google Patents

Abstract

754,510. Steam cooking apparatus ENGWALL & CO., KOMMANDITBOLAG, V. T. Sept. 8, 1954 [Sept. 24, 1953], No. 26012/54. Class 28(1). [Also in Group XI] Food is prepared by heating it in an atmosphere of superheated steam at above atmospheric pressure in a hermetically sealed oven with uniformly conductive, e.g. metallic, walls heated uniformly to a temperature exceeding that of the steam in the oven. As shown, electric heating elements 3 are placed between ribs 13 on the outside of an oven 1 having a door 2 capable of being hermetically sealed. Steam generated in a boiler 4 by a cartridge heater 6 controlled by steam pressure regulator 24 is supplied to the oven 1 at a pressure of about 28À5 pounds per square inch through a pipe 7 having a steam cock 14 and a relief valve 17. The water fed to boiler 4 is controlled by a cock 20 and level control means 8, a non-return valve 21 preventing steam from entering the water pipe. A relief valve is provided for the oven, which may be evacuated through a pipe 9 controlled by a valve 15. The oven may be cooled by supplying water to it through pipe 10 controlled by water cock 16 and provided with a non-return valve 22 to prevent steam from entering the water pipes. A thermostat 23 controls the current supply to elements 3 and hence the oven temperature. Infra-red lamps 11 may be provided. The oven may be heated by gas instead of electricity and it may be cylindrical. Food to be cooked is placed in the oven which is sealed and then steam is admitted, valve 15 remaining open to allow air out until the pressure is between 1À4 and 2À8 pounds per square inch. After some time the steam may be cut off and the oven evacuated before heat treatment is continued. Otherwise the pressure may be reduced to atmospheric and the cooking completed. Examples are given of temperatures, pressures and times of cooking for various food stuffs.