Patent GB-755770-A (GB)
Title: Process and apparatus for coating or enrobing edible articles with edible fat base coating
IPC: A23G3/22
Filed: 1954-04-30
Abstract: 755,770. Coating bakers' &c. goods. OAKES CORPORATION, E. T. April 30. 1954 [May 4, 1953], No. 12662/54. Class 28(1). [Also in Group XIII] Cakes, candies and the like are enrobed with a fat base coating material, such as chocolate, by withdrawing coating material from the bottom of a large stock of tempered, fluid, coating material in which all of the fat melting above the temperature of the stock has crystallised, showering the withdrawn material over the articles to enrobe them, returning the excess coating material to the top of the stock, adding melted chocolate to the top of the stock to maintain at least an hour's supply and mixing the returned coating material and the melted chocolate with the tempered chocolate at the top of the stock. The enrobed articles are conveyed to a cooling zone in which a temperature of 65‹F. to 70‹F. is maintained and where air of low relative humidity is blown over the articles at high velocity, e.g. 2000 to 3000 feet per minute, to cool and harden the coating material. As shown, the enrobing apparatus comprises a tempering kettle 22 with a valve controlled conduit 23 for supplying chocolate to a flow pan 10 which is provided with slide valves 13, 14 whereby the coating material may be released, in the form of one or two curtains, on to articles A carried by a wire conveyer 15, the excess coating material passing through the conveyer into a sump 16. The articles on the conveyer may be given a bottom coating by rolls 37. The tempering kettle is provided with a water jacket 22a through which tempered water may be circulated to maintain the kettle and its contents at the desired temperature, i.e. between 91À5‹F. and 92-5‹F., and contains an agitator 24 driven by a motor 26 at a relatively low speed, the agitator comprising arms 27 extending radially from a shaft 26 and provided with metal scraping blades 28 which brush the inner wall of the kettle. Supplies of chocolate are fed to the top of the tempering kettle by way of conduits 34, 31 from a melting kettle 30, the conduit 31 being connected to the intake of a pump 32 and also to a discharge conduit 33 of the sump so that the tempering kettle may be fed from both sources. The coated articles are delivered by a downwardly inclined portion of conveyer 15 to an endless conveyer 40, e.g. of polished corrosion resistant metal, which is supported by rollers 41, 41a, Fig. 3, and.has its upper flight enclosed in a cooling tunnel 42. The upper flight of the conveyer divides the housing or tunnel into upper and lower air ducts 43, 44 and the upper air duct is in turn divided into sections 45, 46, 47, 48 through which air flows in contact with the articles carried by the conveyer. The air-duct sections 45, 46 are connected at their adjacent ends to an air conditioning unit 49 and at their other ends downwardly extending ducts 51, 52 return air to. the lower duct 44. At the inlet end of the tunnel the air duct section 45 is enlarged by provision of a larger casing portion 50 to reduce the velocity of the air and prevent freshly coated articles being blown along the conveyer. The duct sections 47, 48 are similarly supplied with air from an air conditioning unit 53 and to which return ducts are also provided. The tunnel may be provided with one or more than two sections. Control of the air velocity in the housing and at the discharge end may be facilitated by providing adjustable damper plates 54. In order to eliminate the screen pattern of the mesh conveyer from the botton coatings on the articles A, electric heaters 55, 56 are positioned beneath the lower flight of the conveyer 40 near the entrance to the tunnel so as to keep the chocolate soft until it conforms to the smooth surface of the conveyer 40. The conveyer 40 may be heated and given a thin film of moisture, to prevent adhesion of the articles, by directing low pressure steam on to it by means of a steam pipe 57, Fig. 1.