Fig. 4 Changes of LSO self-diffusion (D) trend at 25, 40, 60, 80, 100, 120oC during 168 h. (25 and 40oC designated as Slow Ox, and 60 80, 100, 120oC designated as Rapid Ox)
The D values in Fig. 4, at different times of LSO oxidation were correlated in Fig 5 to the 1H LF-NMR T2 mobility values of the LSO omega-3 PUFA-rich tail end of the alkyl chains. As can be seen in Fig. 5, there is a good correlation between the D and T2 values. Again the two main autoxidation mechanisms can be observed. One mechanism at low temperatures of oxidation is characterized by negative slope over the 168 h of oxidation, due to a slow oxidation rate of LSO. The second oxidation mechanism at higher temperatures is characterized by a positive slope for 168 h, due to a rapid oxidation rate of LSO. The temperature of 60oC also shows a positive slope, but more moderate than at higher temperatures. This last result supported with correlation of self-diffusion vs. viscosity (supplemental information 1) and T2 vs. viscosity (supplemental information 2) further confirms that 60oC is the temperature point for initiating a rapid LSO oxidation and aging.