Method and apparatus for sterilization with incremental pressure reduction

Abstract

An apparatus and method for sterilization of water compatible products, especially food products such as sliced vegetables, chopped meats etc. A sterilization conduit through which the product passes under pressure includes steam injectors, with the pressure of the product being maintained. The steam is condensed to a liquid by the effect of product temperature and pressure within the conduit and permeates the product. The product thus raised to a sterilization temperature. The heated and pressurized product is then passed through a series of flash chambers, each allowing an incremental pressure decrease upon the product. Each pressure decrease will allow a portion of the liquid permeating the product to flash to the vapor phase, reducing the temperature and added water content of the product while preventing damage to the product caused by excessive flashing. These incremental pressure reductions continue until the product is at atmospheric pressure and a temperature below approximately 100.degree. C. (212.degree. F.), allowing greater ease in packing of the product. Each of the flash chambers includes a product inlet near the top of the chamber such that the pumped product will accumulate at the bottom of the chamber reducing product burn on and build up. A distribution cone may be located below the product inlet to provide an even distribution, and thus an even flashing, of the product.

Dependencies are inferred from the claim text.