Effect of moisture content on the engineering properties of Jamun (Syzgium cuminii) seed

Engineering properties as a function of moisture content are important for food processing and equipment designing, assessment of other properties, and for the product quality determination. Different engineering properties of Jamun seeds depending upon the moisture content in the range of 11.54 to 26% (db) were studied. It was noted that various properties like, length (L), breadth (B), thickness (T), and geometric mean diameter (D-g) increased linearly with increasing moisture content. The seed surface area (S-a), seed volume (V), thousand seed mass (M-1000), increased from 220.5 to 303.2 mm(2), 257.2-443.7 mm(3), 0.28-0.37 kg, respectively, with increasing moisture content. As the moisture content increased, bulk density (rho(b)) and true density (rho(t)) decreased from 899.33 to 778.66 and 1,270.89 to 1077.75 kg/m(3), respectively, while porosity increased nonlinearly from 26.2 to 27.7%. With the increased moisture in seeds, the angle of repose increased linearly from 27.4 to 33.5 degrees. Static coefficient of friction also increased from 0.23 to 0.40, 0.29 to 0.42, and 0.57 to 0.73 for glass, cardboard and plywood surfaces, respectively, with the increasing moisture content. Practical Applications The physical properties of Jamun seeds will be helpful in machine designing for industrial processing and fabrication of postharvest handling equipment like sorter, grader, collector, dryer, pulper, and grinder. These properties may help in designing of grinding, packaging machines, and storage structures.