Physico-chemical properties of rapeseed after different treatments of air drying temperature and storage | Fizikalno-kemijska svojstva sjemenki uljane repice nakon razlicitih tretmana temperature zraka susenja i skladistenja

This paper presents a three year research conducted on the seed of 6 rapeseed cultivars (Alaska, Bristol, Express, Eurol, Lirajet, and Silvia) from primary production to storage. After the soil taken from the district of Daruvar (Croatia) was analysed, it was submitted to the identical cropping intensity, with the goal of achieving a higher yield. The harvesting was conducted on the same day of the year for all cultivars and the basic physical and chemical properties (mass of 1000 seeds, water and oil content, and content of free fatty acids (FFA)) were determined before storing. The drying was conducted in laboratory drier at the 1.0 m/s air velocity and three different air temperatures, namely 40, 60, and 80 deg C. After drying, the rapeseed seeds were stored and the influence of storage conditions on the quality of seeds in rapeseed was determined, namely on the oil and free fatty acids content, which are the two most important rapeseed quality parameters. The rapeseed seeds were stored in three conditions: in storage facility with controlled atmosphere (with temparature of 4 deg C and 10 deg C, and relative air moisture about 70%) and in storage facility without atmosphere control. During a one year storing period, the samples mass was monitored monthly while oil content, FFA content and seed moisture in cultivars were determined. Storing in conditions without atmosphere control showed that the samples mass varied, while the sample storing in the controlled atmosphere showed variations in sample mass with minor oscillations during the whole storing period, which resulted with lower FFA content in comparison with the samples stored without atmosphere control. The oil content after storing in facility without atmosphere control decreased, while the FFA content after storing in the same conditions rose in all seeds samples. In conclusion, storing in controlled atmosphere showed better results in rapeseed quality.