Oxidative stability of sunflower and olive oils: Comparison between a modified active oxygen method and long term storage

Abstract

Shelf-lives of sunflower oil and olive oil were estimated using an Accelerated Shelf-life Testing (ASLT) method and these were compared with the values in long term storage. In addition, the effect of type, oxygen permeability, and transparency of the packages on the shelf-lives of oils were investigated. The determinations were based on the oxidative stability of oils by measuring their peroxide values. The limiting peroxide value corresponding to the end of shelf-life was obtained from the FAO/WHO standards. The shelf-lives of sunflower and olive oil samples in retail store conditions were estimated as 10.6 and 20.8 mo, respectively. Storage lives of sunflower oil in polyethylene tere-phthalate (PET), clear glass and colour glass bottles under a 10 W fluorescence lamp were 10.4, 11.1 and 11.8 mo at 10°C, and 4.8, 5.1 and 6.5 mo at 20°C, respectively. Long term storage lives of olive oil in PET, clear and coloured glass were 17.5, 17.8 and 18.3 mo at 10°C, and 8.0, 8.4 and 8.7 mo at 20°C, respectively. These long term storage lives were then compard with the ASLT results obtained from the modified active oxygen method using a simple shelf-life plot approach. © 1993 Academic Press.