The objective of the research carried out within the paper was to determine efficiency of pressing oil from rape seeds with the use of saturation with organic solvent. The scope of the paper covered an initial processing of the material and the pressing process with the use of a one - screw press along with testing the amount of oil which was formed in the time and electric energy units necessary for pressing it. Four rotational speeds of the press screw were applied: 20, 30, 40, 50 rotations·min-1 and three diameters of the outlet nozzle: 6, 8, 10 mm. Rape seeds were saturated with solvent (24 hours before pressing) - methyl alcohol (methanol) in the mass proportion 1:40 and 1:20. The highest efficiency of pressing was 6.3 (kg of oil)·h-1 at 6 mm diameter of the nozzle and 50 rotations·min-1 for rape saturated with methanol in the 1:20 proportion. The biggest oil mass to pomace mass ratio – 0.624 and 0.610 (kg of oil)·kg of pomace-1 at 6 mm diameter, 20 and 30 rotations·min-1 for rape with methanol 1:20. The lowest energy consumption of the process – 0.1051 and 0.1054 kWh·(kg of oil-1) at 10 mm diameter and 50 rotations·min-1 which corresponds to the highest energy efficiency – 9.515 and 9.487 (kg of oil)·kWh-1.
The objective of the paper was to investigate the fragmentation time of extrudate on its degree of fragmentation and determination of water absorption indices WAI and water solubility WSL as factors describing each obtained fraction. Two types of extrudate produced of one mixture of wheat flour (60% participation) and grits (40% participation) were used for the research. Mixtures were subjected to the process of extrusion with the use of a single-screw extruder and a double-screw extruder. The produced extrudates were ground in the universal mill in: 8, 10 and 15 seconds. Then, fractions were separated on a laboratory sieve. It was found out that the smallest fraction (0.05-0.1 mm) and the biggest fraction (above 0.5 mm) of the extrudate was characterised with the highest solubility and the lowest water absorption. Time of fragmentation of the extrudate influences the changes of the grain size composition of the fragmented extrudates. However, no significant impact of the fragmentation time on the changes of WAI index for the same fraction of the fragmented extrudate was reported.