ISSN 1392-3196 / e-ISSN 2335-8947
Zemdirbyste-Agriculture, vol. 103, No. 2 (2016), p. 183–192
Physical and chemical properties of soybean seeds determine their susceptibility to mechanical damage
Piotr KUŹNIAR, Ewa SZPUNAR-KROK, Pavol FINDURA, Jan BUCZEK,
The research was carried out to determine the influence of the chemical composition and moisture content in seeds from selected soybean cultivars on their mechanical properties. The individual seeds were investigated at five moisture contents in the conditions of quasi-static loads with the use of a Zwick universal testing machine. Mechanical properties of the soybean seeds from the analyzed cultivars depended on their chemical composition and moisture content. The seeds of the cv. ‘Herta PZO’ ruptured when the significantly smallest amount of the rupture force (105.6 N) was applied and were most prone to deformation (29.2%). The seeds of the cv. KS-40 were significantly less prone to deformation (16.7%) and ruptured with the smallest amount of energy (71.5 mJ) applied. The cv. ‘Petrina’ required the significantly highest amount of force (140.6 N) necessary for seed rupture, while the significantly highest modulus of elasticity (1721 MPa) was observed in the cv. SP-16. The cv. ‘Aligator’ required application of the significantly highest amount of energy (142.7 mJ). An increase in the moisture content in seeds caused a significant decrease in the rupture force and modulus and an increase in deformation and energy. Soybean seeds with higher protein and ash content ruptured when higher force was applied and were characterised by a higher modulus of elasticity, smaller extent of deformation and lower energy, being therefore more resistant to damage. Soybean seeds containing more fat and fibre were more prone to damage. Together with the increase in the moisture content (7–19%), we observed a decrease in the impact of the chemical components analyzed on the rupture force and the modulus of elasticity. At the same time we observed an increase in the influence of the tested components on deformation and energy.
Key words: chemical composition, mechanical properties, moisture content.
Full text: 103_2_str24.pdf