2004 Volume 53 Issue 4 Pages 157-166
The standard JOCS method for computing peroxide (PV) using acetic acid / iso-octane mixture as solvent has been in use since 1996, but it cannot be used in the case of sesame oil. The JOCS method could also not be used for palm olein, virgin olive oil and virgin rapeseed oil. The authors have thus established an improved method that would be applicable to sesame oil as well as other vegetable oils. The results obtained with it in this study were compared with those by the JAS method. The improved method involved attention to specified amounts of solvents and saturated KI, and standing time subsequent to saturated KI solution addition. 60 mL solvent, 1 mL sat. KI soln. and 5 min of standing time, instead of 50 mL, 0.1 mL and 0 min in the JOCS method, respectively, were found to give accurate values comparable to those by the JAS method. The relative error by the improved method, as the quotient obtained by dividing PV difference between JAS and this method by JAS-PV, were within 15% for all the above oils except cottonseed and high linoleic sunflower oils.
