Chemical and Chromatographic Studies on Dimeric Fatty Acids (Heated Fats)

Dimer acids, representative of those from thermal-oxidative reactions in fats and oils, differing in polarity and structure and including the thermal, dehydro and bicyclic dimers of methyl linoleate, the dehydrodimer of methyl oleate, the tetrahydroxy and dihydroxy dimers of methyl stearate and the diketo dimer of methyl stearate were synthesized, purified and chemically characterized by the use of mass spectrometry, spectroscopy and chemical analysis. Effective chromatographic systems including gel permeation chromatography, high performance size exclusion chromatography, gas liquid chromatography, high performance liquid chromatography and thin layer chromatography were developed in order to identify and isolate dimer present in an oxidation mixture (GPC, HPSEC, GLC, TLC) as well as to separate dimeric mixtures according to polarity (packed and capillary GLC, reverse and normal HPLC) and into their isomeric components (capillary GLC). Furthermore, dimeric acids from two differently oxidized oil samples were isolated, structurally characterized and the mechanism of their formation explained.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Food Science

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Christopoulou, Constantina Nicholaos

• Agriculture, Food Science and Technology

Identifier

(UMI)AAI8701463

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/70093