Reactivation of the cellulose acetate gel bead column used for the removal of limonin from citrus juices

Abstract

AbstractSimple water washes reactivated a cellulose acetate gel bead column after its use to remove the bitter principle limonin from citrus juices on a pilot‐plant scale, preferably after the passage of 10 bed volumes (BV) of juice. Initially, washes with water equal in volume to the treated juice were effective because they removed inhibitors of limonin adsorption but the column would eventually become poisoned. A regime was established for long term operation of the column from the results of monitoring the limonin content and chemical oxygen demand of the wash waters. These results could be fitted to standard mathematical equations for extraction processes and these equations were used, in conjunction with previously developed equations for the adsorption of limonin from citrus juices, to calculate the conditions for the steady‐state operation of the column. A three‐column unit is suggested as a suitable basis for the adsorptive treatment of juice within a continuous processing line. Ten BV of juice would be passed through two of the columns in series at 2.5 BV h−1 reducing the limonin content by about 50‐70% while the third column was being reactivated by the passage of 16 BV of warm water at 3.8 BV. After 4 h−1, the first of the two linked columns would be reactivated and the second would become the first of the new pair of linked columns with the newly reactivated column as the second component.