| 摘要 |
1,198,297. Concentrating liquids by freezing. SOC D'ETUDES ET DE TRAITEMENTS DE PRODUITS ALIMENTAIRES ET MEDICINAUM. 13 Oct., 1957 [14 Oct., 1966], No. 45899/67. Heading B1G. In a process for concentrating liquid food products by freezing, the liquid is cooled in a first stage to form ice crystals at -‹to 0‹C. and is then cooled in a second stage to -50‹ to -30‹C. to enlarge the ice crystals. As shown liquid is passed to a feed tank 1A whence it is passed to a first crystallizator in tank 4A which is surrounded by a jacket to which refrigerant is supplied at a temperature between -10‹ and 0‹C. The liquid is agitated in the tank 4A from which it passes to a second crystalizator-tank 10A in which it is in direct contact with refrigerant at a temperature of between -50‹ and -30‹C. The ice/liquid mixture then passes to a centrifuge 12A from which concentrated liquid is passed by a pump 33A to further concentration cycles B and C. Ice is passed from the centrifuge to a crusher 32A and after melting in a heat exchanger 38 is delivered to a wash liquid distributor 26A. Liquid produced by washing is passed by a pump 35A to the feed tank 1A. Ice crystals from the centrifuge may be passed to the tank 4A through a line 40A. Nitragen is admitted to the feed tank, the first crystallizator tank, and the tank in which the concentrated product is ultimately collected to provide an inert atmosphere. Following concentration the liquid may be subjected to an atomization or lyphilization process, preferred operating conditions are disclosed and liquid food products suitable for treatment in the process are listed. |
