Physical properties of sesame seeds harvested at different maturation stages and thirds of the plant

Abstract

The quality of sesame (Sesamum indicum L.) seeds is directly influenced by their physical characteristics, which are seldom studied notwithstanding their extreme importance in the entire production chain. Therefore, the objective of this study was to quantify the physical properties of two types of sesame seeds, collected at three points in the plant with different maturation levels, measured with digital caliper, and to evaluate the feasibility of using a digital image to determine their physical characteristics. The seeds were initially evaluated for water content and mass of 1000 seeds, and later with the data of the characteristic dimensions A (length), B (width), and C (thickness), obtained by a caliper and digital images, we determined their sphericity, circularity, projected area, and geometric diameter. We observed that water content did not affect the physical properties of the cream (CNPA G4) and black sesame cultivars. In addition, seeds of the black cultivar presented higher results than the seeds of the cream cultivar for the mass of 1000 seeds (2.7 ± 0.08 g), sphericity (58.8 ± 0.47%), projected area (4.03 ± 0.12 mm2), and geometric diameter (1.65 ± 0.03 mm). Seed batches harvested after 70% maturation had the highest mass of 1000 seeds (2.7 ± 0.12 g). The results of the physical analyses of sesame seeds performed with caliper and digital image are equivalent, which shows that digital images can be used as tools to obtain the physical properties of seeds.