GB897770A - Improvements in or relating to the pasteurisation of beverages in bottles - Google Patents

Abstract

897,770. Pasteurizing foods in sealed containers. BARRY - WEHMILLER MACHINERY CO. July 14,. 1960 [July 23, 1959], No. 24525/60. Class 49. [Also in Group XIII] In the pasteurizing of products such as alcoholic or non-alcoholic foods packaged in closed containers, involving the steps of raising the product temperature in a first zone followed by product cooling in a subsequent zone, a refrigerating medium is circulated between the zones to provide in the first zone heat of condensation which is transferred to the product to induce the rise in product temperature. Bottles of products P, conveyed on a load-carrying grate or walking-beam platform 73 of the character described in Specification 690,181 (see Group XXX), are pre-heated by warm water sprays issuing from a header 84, are pasteurized by hot water sprays from the header 91 and the pasteurized products are cooled by sprays of water from headers 97 and 101; the sprayed water is continuously recirculated in the respective zones by pumps 86, 92, 98 and 103. The refrigerating system includes a compressor 85, condenser coils 88, a receiver 107, a high-temperature evaporator 100 and a low-temperature evaporator 104. Undue variations in the temperature of the pre-heating water in the reservoir 74, normally maintained constant by the condensation of the refrigerating medium in the coils 88, may be remedied, for example at the commencement and termination of operations by the provision of a temperaturecontrolled steam-heating coil 81 and a supply of cooling water through a temperature-controlled valve 89; an overflow 90 prevents excess filling of the reservoir. The water in reservoir 75 for effecting pasteurization is heated by steam supplied to a coil 94 through a temperatureactuated valve 96. The temperature of the cooling water in the reservoir 77 is kept constant by the controlled evaporation in the evaporator 104 of refrigerating medium snifted through a thermostatic expansion-valve 109; a control switch 120 causes the compressor 85 to be stopped or unloaded when excessive suction pressures arise from the closure of valve 109. Pre-cooling by water from the reservoir 76 may be similarly effected by evaporating refrigerating medium in the evaporator 100 under the control of a water temperature-actuated expansion valve 113; a further valve 116, solenoidoperated in response to the water temperature, is incorporated to allow the two evaporators to operate at different temperatures from the same compressor, condenser coils and receiver. It is stated that when products in metal containers are being processed, this pre-cooling may be omitted. Figs. 4, 5 and 6 (not shown), depict conventional systems of pasteurizing apparatus.