Integrated system of progressive freeze-concentration combined with partial ice-melting for yield improvement

Abstract

AttachedA 25L-scale tubular ice system for progressive freeze-concentration was constructed and combined with a 75L-scale partial ice-m elting system for yield improvement. From the measurement o f freezing point of various fruits juices, nine standard operation programs were prepared in cooling and circulation flow rate for the tubular ice system. The standard programs were successfully tested for progressive freezeconcentration o f sucrose solutions with concentration varied from 3 to 30%. By choosing one o f the standard program, apple juice was effectively concentrated from 12.8 to 21.0 Brix with 79.0% yield, which was improved to 90% by recovering the 30% o f the initially-melted fractions by using the partial ice-melting system. The tubular ice system can be easily scaled-up more, if necessary, simply by increasing the number o f tubes.