| A 22% CLA rich-soy oil has been produced by soy oil photoisomerization with an iodine catalyst. However, the isolation and characterization of the TAG's in CLA-rich oil has not been described. The goal of this research was to develop a micro-method for fatty acid analysis to be used to determine CLA fatty acid profiles of small fractions obtained by HPLC. We developed a micro-method, which is sensitive, precise, accurate and suitable for analyzing fatty acid composition of limited oil samples by GC-FID. Qualitative examination of these TAGS was conducted by reversed-phase high performance liquid chromatography (RP-HPLC) with an ACN/DCM gradient and two C18 columns, 5microm, 250 x 4.6 mm i.d. each and evaporative light scattering detector (ELSD) and ultraviolet (UV) detection at 233 nm. New TAG peaks were observed that were probably derived from linoleic acid containing TAGS. The LnLL, LLL, LLO and LLP declined after photoisomerization with an increase in new adjacent peaks that co-eluted with LnLnO, LnLO, LnOO and LnPP. In order to conclusively quantify the fatty acid content of TAG's, a semi-preparative RP-HPLC system (2 C 18 columns, 5microm, and 250 x 10 mm i.d. each) was used to allow sufficient RP-HPLC fractions sizes to be collected for FAME analysis of each fraction. Linoleic acid rich TAG fractions contained most CLA after processing. The TAG's converted to CLA were LnLL, LLL, LLO and LLP. The quantitative RP-HPLC and GC data confirmed the qualitative data and showed that the semi-preparative RP-HPLC method has potential in producing high CLA TAG fractions. However, further work is needed to obtain better resolution for preparative HPLC TAG separation. |
