Preservative method and preserved fruit or vegetable product, using citric acid, sodium and calcium chloride-containing preservative composition

摘要

Food pieces, such as cubed apples, the exposed pulp of which tends to discolor upon exposure to air, are treated with an acidic aqueous solution which is effective in maintaining the natural color of the exposed pulp and which comprises citric acid, calcium chloride, and sodium chloride, with the treatment of such apples being preferably practiced by means of novel apparatus which uses a screw conveyor which receives the pieces of food at its inlet end and moves them from its inlet end to its outlet end automatically while the treating solution is continuously injected into the conveyor to coat the food pieces. Injection of the treating solution is controlled in response to control signals derived from a gamma ray weigh scale which weighs the food pieces continuously as they pass through the conveyor, so that the amount of treating solution injected is maintained in predetermined proportion to the rate at which the food pieces pass through the conveyor.