Assessment of Sterol Oxidation in Oils Recovered from Exhausted Bleaching Earth by Coupled Capillary Column GC and GC–MS Methods
2012 (English)In: Journal of the American Oil Chemists Society, ISSN 0003-021X, E-ISSN 1558-9331, Vol. 89, no 8, 1427-1433 p.Article in journal (Refereed) Published
Cholesterol and phytosterols are generally present in foods at ppm levels and they can generate many oxidation products, i.e. oxysterols. The oxysterols comprise only a small percentage of unoxidized sterols. Reliable quantitative data on these compounds requires reasonably good separation by capillary column GC. The present study attempts to overcome the difficulties involved in separating many common oxysterols generated from cholesterol, brassicasterol, campesterol, stigmasterol, and sitosterol by coupling two high-resolution GC capillary columns. The columns, DB-17MS and DB-35MS, were coupled separately to a DB-5MS column. Total separation time of the authentic samples of oxysterols was 41 min for the DB-35MS/DB-5MS and 44 min for the DB-17MS/DB-5MS coupled columns. Two oil samples EBE1 and EBE2 extracted from exhausted bleaching earth collected from Europe were analyzed for oxysterol content by using these column combination systems. Both systems showed similar quantitative results; the total levels of oxysterols in these samples ranged from 2 to 3 mg/100 g. The prominent oxysterols were as follows: 7α-hydroxysterols (0.29–0.49 mg/100 g), 7β-hydroxysterols (0.13–0.68 mg/100 g) and 7-ketosterols (0.63–0.69 mg/100 g).
Place, publisher, year, edition, pages
2012. Vol. 89, no 8, 1427-1433 p.
By-products, Combined two-dimensional capillary columns, COPs, EBE, Exhausted bleaching earth oil, Feeding fats, Oxysterols, POPs, SOPs
IdentifiersURN: urn:nbn:se:uu:diva-172395DOI: 10.1007/s11746-012-2053-7ISI: 000306789100007OAI: oai:DiVA.org:uu-172395DiVA: diva2:514539