6. Conclusion

Fat extraction and assay must be adapted to the matrix to be studied, and lead to total extraction without modification of the lipids. In a number of cases, the fat requires purification prior to analysis. Physical and physico-chemical parameters can be used to characterize fats. However, due to the great diversity of fats, these determinations are often insufficient to identify them unequivocally. It is then necessary to determine the composition of the major constituents: triglycerides, phospholipids and fatty acids. Analyses are performed using separative techniques (GPC and LC) or spectroscopic techniques (NMR, Infrared). Comparison of results with databases often enables fatty substance characterization. In a number of cases, minor compounds present in the unsaponifiable matter need to be taken into account for lipid identification. This aspect is covered in the article