Impact of packaging material and storage time on olive oil quality

Olive oil is very appreciated for its characteristic flavor and its biological and nutritional value which are strongly related to the quality. The effect of packaging materials (stainless, jar, clear polyethylenene terephthalate (PET), clear glass and dark glass bottles) on quality attributes of extra virgin olive oil (EVOO) was studied as a function of storage time (0 to 12 months). The results made it possible to highlight a light influence of time as well as type of container on the acidic composition of oils, although oleic acid slightly increased at the end of the analytical period. Indeed, the least stable oils were those stored in the jars with a progressive increase in quality attributes and the palmitic acid level. A clear reduction in the contents of antioxidants (carotenes, chlorophylls and total phenols) was observed in the oils stored in the earthenware jars and PET. Quality indexes were strongly influenced by the type of packaging material and the time of storage. Overall, the results revealed that the storage of oils in stainless and dark glass appears most adequate, thus supporting the conservation of primarily contents antioxidants with indices of quality indicating an unrefined olive oil lasting storage.