EFFECTS OF EXPRESSION PRESSURES AND DISC SHAPES ON THE EXTRACTION EFFICIENCY aOF A FRUIT JUICE EXTRACTOR

U. J. Etoamaihe

U. J. Etoamaihe Department of Agricultural Engineering, Michael Okpara University of Agriculture, Umudike, P. M. B. 7267, Umuahia, Abia State, Nigeria

Keywords: Juice extractor, concave and convex discs, expression pressure, extraction efficiency, response surface methodology

Abstract

A developed fruit juice extractor was studied for its performance. Some parameters like, expression pressures and
pressure disc shapes diameters were varied to determine their effects on its extraction efficiency using Response
Surface Methodology (RSM). Three levels of expression pressures (80 ,100 and 120 N/mm2
) and three different
diameters of its concave and convex discs pressure plates (60,80 and 100 mm) were investigated. The highest
extraction efficiency of 71.95 % was obtained when the convex disc diameter was 100 mm and the expression
pressure was 120 N/mm2
. Further RSM analysis showed that the linear effects of expression pressures and
convex disc diameter of the juice extractor were significant to its extraction efficiency at 5% probability (P≤0.05).
Also significant are the quadratic effects of concave and convex disc diameters, interactions of expression
pressures and concave disc diameters, interactions of expression pressures and convex disc diameters and
interactions of concave and convex disc diameters. These factors accounted for about 98.58 % of the variations
in the extraction efficiency of the machine