Lithuanian Rapeseed: Quality and Geographical Origin by the Use of Rare Earth Elements

The aim of this work was to identify the geographical origin of various rapeseed oil breeds grown in different regions of Lithuania by the use of rare earth (REE) and other element traces which were measured with inductively coupled plasma mass spectrometry (ICP-MS). For the testing the usefulness of the method 37 rapeseed samples from Lithuania and 12 samples from Austria, Hungary and Croatia were analysed and compared. The chemical composition and the suitability for the edible rapeseed oil production of 5 rapeseed cultivars grown in Lithuania was also determined. It was testified that the oil from Sunday, Landmark, Ural, Heros and Kasimir cultivars are of high quality - because of traces (0.05-0.11%) of erucic fatty acid which in Lithuania are limited to 2%. The chemical oil composition is appropriate to low erucic rapeseed oil - 6.92% of SFA, 65.62% of MUFA and 27.28% of PUFA. The study of total content of phenolic compounds and the oxidative stability was also part of this work. The oleic fatty acid is one of the main factors that describes the oxidative stability of the oil (r = 0.83). The best kind of rapeseed was Ural, which had the highest content of MUFA (69.12%) and was the most stabile (IP = 6.16 h). The mass fraction of Cr, Fe, Ni, Cu, Se, Sr, Ba Pb and U in Lithuanian rapeseed was determined to be in average 0.052, 4.95, 0.20, 0.26, 0.17, 17.9, 1.72, 0.015 and 0.38 mg/kg, respectively. The average mass fraction of iron and copper in Lithuanian rapeseed is 4.95 and 0.256 mg/kg, respectively, were not higher than permissible (5 and 0.4 mg/kg, respectively). The lowest copper mass fraction was discovered in seeds from an ecological farm of Lazdijai in Lithuania, where the cold pressed rapeseed oil is produced 0.2 mg/kg respectively). The mass fraction of lead in Lithuania, Austria, Hungary and Croatia were 50-100 times lower (0.015, 0.021, 0.010, 0.021 mg/kg, respectively) than permissible (1 mg/kg). The REE patterns of the rapeseed sampled from different regions of Lithuania, are very similar, due to the homogeneous soil composition. But, this study also demonstrates that rapeseed from different geographical origin (Lithuania, Austria, Hungary and Croatia) can be distinguished based on REE and other element traces due to significant differences in the chemical composition of the seed.