GB1179408A - Process and apparatus for removing the outer skins of onions - Google Patents

Abstract

1,179,408. Peeling onions. MARELA Ltd., and ENG. & CHEMICAL SUPPLIES & SERVICES Ltd. 31 Jan., 1968 [31 Oct., 1966], No. 48778/66. Heading A4C. Onions are peeled by first slitting the skin and then removing it by means of a blast of fluid. A suitable machine includes a conveyer 6 having apertures of a frustroconical form capable of maintaining an onion 14 in a stable position, the onions being fed on to the conveyer from a hopper (2) and orientating device (4), which conveyer transports said onions to a position in which the skin can be split by engagement of the onion 14 with an electric resistance heating wire 17 extending vertically across the concave face 16 of a block 15. The block 15 is moved in order to contact the wire 17 with the onion 14 by means of a solenoid 34, the onion being held in position by means of a solenoid operated holder 39 comprising a shaft 40 to which is attached the holding body 43 having a radially outwardly extending flanged 43<SP>1</SP>, to the lower circular face of which is attached a rubber or flexible plastic annular plate 44 having a bevelled radially inner wall 45 which contacts the crown of the onion. The conveyer 6, which is driven in a stepwise manner, is coordinated with the solenoid 34 such that the slitting blocks 15 are only activated when an onion is stationary in a position adjacent to the block 15, or in an alternative embodiment, between two of said blocks 15. The wire 17 may be replaced by an abrasive blade or wheel, a saw-edge blade or wheel, or a burner providing a flame having a fine circular section tip or an elongate cross-section. After the splitting block 15 has been separated from the onion 14, the latter is carried on the conveyer to a peeling chamber 46 (Fig. 4) which consists of upper and lower chamber parts 47 and 48, mounted on vertically movable shafts 52 and 53 respectively, enclosing a space 49, sealed with respect to its surroundings, into which peeling fluid is introduced by the inlet conduit 50 and from which peeling fluid is removed by the outlet conduit 51. Air or alternative peeling fluid is passed into the chamber at a pressure of preferably about 20 p.s.i.g. but at least 5 p.s.i.g. and removes the skin of the onion 14, the skinned onion then being passed to a screening belt (20) for separation of the skins from the opions by means of an air blast.