The rates of oxidative rancidity of peanut oil in contact with iron, copper, zinc, aluminum, tin, polyethylene (PE), glass and magnesium were studied. The rancidity of the oil in the surfaces made of these materials decreased in the order Mg>Fe>Cu>Sn>Glass>Zn>Al>PE. The order obtained showed that the rancidity process does not depend on the activity of these surfaces, but has a possible link with surface passivity. The values for the rate of rancidity in Mg and Fe surfaces where the process was fastest were 2.08 × 10-5 and 1.39 × 10-5 mmolkg-1hr-1 respectively, while values for the lowest rates of rancidity obtained for Al and PE surfaces were 2.78 × 10-6 and 1.07 × 10-6 mmolkg-1hr-1 respectively. The use of aluminum and PE vessels for the storage of peanut oil would increase its shelf-life by keeping the oil in its original state for a longer period of time.
International Letters of Chemistry, Physics and Astronomy (Volume 65)
C. E. Duru et al., "Dependence of Storage Material Surfaces on the Oxidative Rancidity Kinetics of Peanut Oil", International Letters of Chemistry, Physics and Astronomy, Vol. 65, pp. 27-31, 2016