초록
This study estimates the classification criteria which distinguishes the types of omega-3 health functional foods, fish oils and fish oil usages through $^{13}C$-NMR spectra and fatty acids contents analysis. The major fatty acids of omega-3, eicosapentaenoic acid (EPA, $C_{20:5}$) and docosahexaenoic acid (DHA, $C_{22:6}$) are being analyzed. 10 ethyl ester (EE) forms and 10 triglyceride (TG) forms are the most common types of fish oils for 20 omega-3 products. Gas chromatography (GC) analysis generally shows the matching EPA and DHA contents of the products listed on the notation. But EE form contents of EPA and DHA are higher and are more varied than the TG form. Most of the samples of EPA/DHA ratio show different content ratios of indicated on the products when comparing with standards. The $^{13}C$-NMR analysis of EPA and DHA on sn-1,3 and sn-2 carbonyl peak position with fish oil triglycerides display whether the reconstituted triglycerides (rTG) are being confirmed or not. As a result of the 9 TG form, the 10 TG products showed similar values: EPA sn-1, 3; 13.46~15.66, sn-2; 3.00~4.52, DHA sn-1, 3; 2.43~4.40, sn-2; 3.84~6.36. But one product showed lower contents (EPA: sn-1, 3; 5.88, sn-2; 2.86, DHA sn-1, 3; 2.29, sn-2; 5.95) of EPA, thus it can be considered a different type of oil and only matched six products according to the label. This study is intended to provide basic materials which identify the status for the types and quality of omega-3 fish oil products according to fatty acids profiles and the $^{13}C$-NMR spectrum confirmed the location specificity of EPA and DHA.