OXIDATION-KINETICS OF MENHADEN OIL WITH TBHQ

The oxidation kinetics of menhaden oil containing 0% to 0.02% tert-but ylhydroquinone (TBHQ) were evaluated at 37 degrees C. Induction period s, and monomolecular and bimolecular oxidation rates were determined f rom thiobarbituric acid analysis. The disappearance rates of several f atty acids were determined from GC analysis. Free fatty acid and visco sity changes were evaluated. Induction periods were directly related t o TBHQ concentration. Monomolecular rates decreased with increasing TB HQ concentration, but bimolecular rates did not change. The rate of di sappearance of unsaturated fatty acids was proportional to their degre e of unsaturation, but not related to TBHQ concentration. Free fatty a cid content and viscosity increased rapidly after the monomolecular pe riod.