Some physical properties of saffron Crocus corm

Abstract

Saffron (Crocus sativus L.) is the most precious spice in the world. This plant is sterile and the saffron propagation is possible only via the cultivation of corms. The physical properties of saffron corms are prerequisite to designing and developing harvesting, handling, sizing and sowing equipments of corms. Therefore, some physical properties of the saffron corm were determined in this study. The experiments were conducted on three sets of saffron crocus corms from main producer areas of Khorasan province, located in Eastern Iran, namely Torbat-e-Heydaryeh, Kashmar, and Gonabad. Our results have shown that there were no significant differences among most of the physical properties in the three different cultivation regions. The mean values of mass, height, major diameter, minor diameter, geometric mean diameter, arithmetic mean diameter, volume, corm density, bulk density and sphericity for the three regions were 4.44 g, 18.80 mm, 21.86 mm, 18.85 mm, 19.73 mm, 19.84 mm, 3.76 cm3 , 0.642 gcm-3, 1.11 gcm-3 and 90.04%, respectively. We have determined the average values of the coefficient of friction for the three corm regions on steel, galvanized steel, plywood, rubber and polyethylene sheets: 0.517, 0.404, 0.462, 0.584 and 0.402, respectively. The natural repose angles of saffron corm for Torbat-e- Heydaryeh, Gonabad and Kashmar regions were also determined: 32.62, 30.56 and 30.31 degree, respectively.