Browsing by Subject "gas chromatography"

Gas chromatography (GC) is one of the most widely used method for analysis of lipids and it is commonly combined to a flame ionization detection (FID), since GC-FID is an excellent combination for quantitative analysis of wide range of lipids. Before GC analysis can be performed, lipids must be extracted from the sample and derivatized. Some common extraction methods include Soxhlet and Soxtec extraction, Folch extraction and extraction with the help of acid hydrolysis. To be able to analyse the extracted fatty acids by GC, they must be in a volatile form. This can be achieved by forming fatty acid derivatives by, for example, methylation. The commissioner wishes to have a way to analyse the fatty acid composition of pork by GC in their laboratory. The aim of the study was to take in use an easy, safe-to-use and simple method for determination of fatty acid composition of pork by gas chromatography, using the instruments and equipment already found from the laboratory. The research had three different parts. First, heptane-isopropanol extraction, Bligh & Dyer extraction and Caviezel extraction were compared. Then the chosen extraction method was validated. Finally, two different pork samples were compared to test the method’s ability to differentiate them. Caviezel extraction was chosen as the best extraction method, and it was validated by parameters repeatability and robustness. The method was able to differentiate samples that had similar, but slightly different fatty acid compositions. However, method still requires some fine tuning since the GC column seemed to be highly sensitive to any disturbances.