Triglycerides are an important part of the human diet; they are also used as medical
supplements to control the symptoms of arthritis and other medical conditions.
Analysis of triglycerides is important to check purity, and confirmation of the structure is
important for authentication of high value products such as olive oil. Currently, this is carried
out using enzyme reactions and the fatty acids on each position of the triglyceride are
analysed separately.
Development of methods for the direct analysis of triglycerides using 1H and 13C NMR has
been carried out as part of this research. Using 1HNMR, a quick, quantitative overview of the
species of fatty acids present in a triglyceride can be achieved. A method of quantitative 13C NMR was developed using Cr(acac)3 as a relaxation agent. This method gave rise to the identification of characteristic signals for each individual fatty acid present in triglycerides on both the alpha- and beta-positions allowing quantitation of individual components. The error present in these NMR method is high in comparison with that from chromatographic methods,
but these NMR methods are designed as a relatively quick method to look at triglycerides semi-quantitatively, not for in-depth, highly quantitative analysis.
These quantitative NMR methods were applied to investigate the triglyceride composition of olive oils and to study the seasonal changes in triglyceride composition of cows' milk. The triglyceride composition of regional cheeses was also studied, and a method to analyse the lipid composition of lamb muscle and fat was developed.