PHYSICAL PROPERTIES OF WATERMELON (CITRULLUS LANATUS) SEEDS RELEVANT TO PROCESSING EQUIPMENT DESIGN

Abstract

This study investigated some physical characteristics of water melon seeds with the aim of utilizing them in the design 
of the processing machinery. Commonly applied techniques were employed to determine the length (mm), width 
(mm), thickness (mm), 1000-unit mass/mass (g), arithmetic mean diameter (mm), geometric mean diameter (mm), 
sphericity, surface area (mm), volume (mm3), true density, bulk density, porosity, static coefficient of friction of 
squash seeds at 7.5% moisture content, and angle of repose. Water displacement method was used to determine the 
seeds volume and density, while electronic weighing balance was used to determine weight. Five different structural 
surfaces were used to determine the static coefficients of friction of watermelon seeds: glass fiber, plywood, glass, 
rubber, and galvanized metal sheet. The results showed that the length was 14.0 mm, the width was 7.07 mm, the 
thickness was 3.69 mm, the mass of one thousand seeds was 40.79 g, the arithmetic mean diameter was 11.02 mm, 
the geometric mean diameter was 9.10 mm, the sphericity was 1.99 %, the surface area was 256.10 mm2, the volume 
was 297.20 m3, the true density was 743.96 kg/m3, the bulk density was 567.20 kg/m3, the porosity was 60.17%, and 
the static coefficients of friction was 7.5. Angles of repose pouring were 40.33°, angles of repose discharging were 
37.24°, glass fiber was 0.37%, plywood was 0.75%, glass was 0.45%, rubber was 0.61%, and galvanized metal sheet 
was 0.59%. The findings will help with an effective layout of equipment for the culinary processing industry's seeding, 
harvesting, processing, conveyance, classification, grouping, and casing of watermelon seeds. Therefore, it is 
concluded that the results of the current research will provide more information about the requirements for machines 
used in watermelon processing as well as handling.