The location of unsaturated fatty acid in triacylglycerols (TAGs) affects their oxidative stability. Herein, we studied the effect of location of conjugated linolenic acids (CLNs) in TAGs on their oxidative stability. First, the TAGs containing CLNs at
sn-1(3) and
sn-2 positions, were enzymatically prepared via Lipozyme RM-IM (immobilized
Rhizomucor miehei lipase)-mediated acidolysis- and contained ca. 60% of CLNs at
sn-1(3) or
sn-2 position. The auto-oxidation test at 30°C in the dark showed oxidative stability of TAGs that mainly contained CLNs at
sn-2 position was higher than that at
sn-1(3) position based on peroxide value, anisidine value, polymeric substance and polar compound contents. Moreover, the thermal-oxidation test at 90°C for 24 h, showed the same result. Furthermore, even after 24 h of thermal oxidation, the oxidative stability of the TAGs containing CLNs at
sn-2 positions rather than
sn-1(3) positions remained at a higher level. Thus, the results showed that the TAG-containing CLNs are stable when the CLNs are located at
sn-2 positions.
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