Author(s)

Ronald A. Holser

Quality and Safety Assessment, Russell Research Center, United States Department of Agriculture, Agricultural Research Service (USDA-ARS), Athens, USA.

Highly unsaturated fatty acids such as docosahexaenoic acid and linolenic acid are prone to oxidation with a resulting loss of bioactivity and generation of malodorous degradation compounds. Degradation proceeds by formation of the corresponding hydroperoxyl free radical with subsequent oxidative cleavage at the double bond site. FTIR-ATR was used to detect degradation through spectral changes that were correlated to oxidative degradation. The spectrometer was equipped with a heated stage so that a series of spectra could be collected while the sample was exposed to elevated temperatures. The appearance of new bands at 972.8 cm^﹣1, 2934 cm^﹣1, and 3498 cm^﹣1 with the disappearance of bands at 703.6 cm^﹣1 and 3013 cm^﹣1 were observed after heating and these spectral changes were evaluated by correlation spectroscopy analysis. These results provide a method to quickly detect the oxidative degradation of polyunsaturated fats. This approach is expected to be applied for the quality assessment of feed formulations fortified with omega-3 fatty acids.

Correlation Spectroscopy, Infrared Spectroscopy, Polyunsaturated Acid, Linolenic Acid

Holser, R. (2014) Docosahexaenoic Acid Ester Degradation Measured by FTIR-ATR with Correlation Spectroscopy. American Journal of Analytical Chemistry, 5, 373-377. doi: 10.4236/ajac.2014.56045.