title: Mechanical hulling and thermal pre-treatment effects on rapeseed oil antioxidant capacity and related lipophilic and hydrophilic bioactive compounds.
abstract: In this study, the effect of rapeseed mechanical hulling and thermal pre-treatment by microwaves (from 2 to 10 min with 2-min intervals, 800 W) and roasting (from 20 to 100 min with 20-min intervals, 165 °C) on the content of phytochemicals in the oil was investigated. Results showed that both pre-treatments applied differentiated the oils in terms of the content of bioactive compounds. In general, oils pressed from hulled and thermally pre-treated seeds contained higher content of tocopherols, PC-8 and phytosterols, while oils pressed from non-hulled and pre-processed seeds had significantly higher concentration of polyphenols. Both microwaving and roasting contributed to an increase of antioxidant capacity of studied oils. The increase of radical scavenging activity of oils was seen mainly in hydrophilic fraction of oil, which was highly positively correlated with the amount of canolol formed during seeds heating.
authors.affiliation: a Department of Food Technology, Faculty of Food Sciences , Warsaw University of Life Sciences , Warsaw , Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Rękas
authors.affiliation: a Department of Food Technology, Faculty of Food Sciences , Warsaw University of Life Sciences , Warsaw , Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Wroniak
authors.affiliation: b Department of Food Biochemistry and Analysis, Faculty of Food Sciences and Nutrition , Poznań University of Life Sciences , Poznań , Poland.
authors.forename: Aleksander
authors.initials: A
authors.lastname: Siger
authors.affiliation: a Department of Food Technology, Faculty of Food Sciences , Warsaw University of Life Sciences , Warsaw , Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Ścibisz
authors.affiliation: c Department of Biotechnology, Microbiology and Food Evaluation, Faculty of Food Sciences , Warsaw University of Life Sciences , Warsaw , Poland.
authors.forename: Dorota
authors.identifier: http://orcid.org/0000-0002-2817-6513
authors.initials: D
authors.lastname: Derewiaka
authors.affiliation: d Department of Machines and Research Methodology, Faculty of Technical Sciences , University of Warmia and Mazury in Olsztyn , Olsztyn , Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Anders
mesh_terms: D029741:Brassica rapa / Q000737:chemistry*; D005511:Food Handling / Q000379:methods*; D016166:Free Radical Scavengers; D006358:Hot Temperature; D000074262:Rapeseed Oil / Q000737:chemistry*; D024505:Tocopherols / Q000737:chemistry*
chemical_list: D016166:Free Radical Scavengers; D000074262:Rapeseed Oil; D024505:Tocopherols
keywords: Hulling; microwaving; phenolic compounds; phytosterols; radical scavenging activity; rapeseed oil; roasting; tocopherols