Moisture dependent physical properties of wild safflower (carthamus oxyacanthus) seeds

Abstract

Measuring physical properties of crops is necessary for optimal harvesting, cleaning, threshing, sorting, drying, and milling operations. Despite an extensive literature review, there is no information about the physical properties of the wild safflower seed. In this study the physical properties of the wild safflower seed have been investigated as a function of moisture content at four levels (5.4%, 9.4% (initial), 13.4%, and 17.4% d.b.). The average length (mm), width (mm), thickness (mm), arithmetic mean diameter (mm), geometric mean diameter (mm), sphericity (%), volume (cm³), seed surface area (cm²), terminal velocity (m/s), bulk density (gr/cm³), actual density (gr/cm³), and porosity (%)  at initial moisture content  were 6.418, 3.499, 3.388, 4.435, 4.229, 66.617, 40.63, 56.66, 3.41, 0.666, 0.949, and 30 respectively. Changes in moisture content had a significant effect on all geometric and gravimetric properties (p ≥ 0.001). With increase in moisture content, all properties increased, except for sphericity and bulk density. The average static coefficient of friction of wild safflower seed at initial moisture content on glass, stainless steel, and plywood surfaces was 0.38, 0422, and 0.426 respectively.