Chemical Evaluation of Rapeseed

TLDR

Rapeseeds are characterized by high lipid and protein contents. The study examined the seed chemical composition and oil physical and chemical constants of two German rapeseed varieties and one Egyptian variety. Unsaponifiables were fractionated by gas‑liquid chromatography into 36 compounds, 26 of which were identified as hydrocarbons. Fatty acid analysis showed palmitic and oleic acids as the predominant saturated and unsaturated acids, with no long‑chain (>C18) fatty acids present; hydrocarbons with C20–C24 were most common, and German varieties contained appreciable campesterol, stigmasterol, and β‑sitosterol, whereas these sterols were only trace in the Egyptian seeds.

Abstract

Abstract The seed chemical composition and oil physical and chemical constants of two imported rapeseed German varieties and one locally produced in Egypt were studied. Rapeseeds are characterized by high lipid and protein contents. The fatty acid analysis indicated that palmitic and oleic acids were the most prevalent saturated and unsaturated acids, respectively. Also, the rapeseed oils under study were free from long‐chain fatty acids (>C 18 ). The unsaponifiables were fractionated by GLC into 36 different compounds of which 26 hydrocarbons were identified. The hydrocarbons having carbon atoms between C 20 and C 24 represent the most common compounds. Campesterol, stigmasterol and β‐sitosterol were present in appreciable amounts in German varieties while these compounds occurred as trace substances in the seeds produced in Egypt.