EFFECT OF PULPER-FINISHER OPERATION ON QUALITY OF TOMATO JUICE AND TOMATO PUREE

Preliminary tests were done on the performance of an existing pulper finisher design with two unadjustable blades. Quality parameters such as consistency index and yield were determined at screen sizes of 0.5, 1.0, 1.5 mm and speeds: 100, 300, 500 and 700 rpm. Design modifications were made on the pulper finisher by addition of another blade and slide tapering of blades to allow smooth jlow of material on one direction. Quality parameters such as consistency index, pulp/serum ratio, particle size distribution, total solids and total yield were evaluated. A maximum quality index in terms of total solids, pulp/serum, consistency, particle size distribution was achieved at screen size 1.0 mm and a speed of 700 rpm. Maximum yield of tomato juice however, was obtained with screen size of 1.5 mm and a speed of 700 rpm. Results of the comparative tests done on existing and modified pulper finisher showed that quality and quantity of tomato juice and puree from the modified unit is better and higher. A 3 % increase in yield was observed from the modified unit.