ABSTRACT
Olive oil may have to be stored for many months. If specific precautions against deterioration are not taken, this will cause an increase of acidity due to the action of lipases and the development of rancidity. Tanks or drums for storage should be constructed of material which is impermeable to oil. e interior should be inert so that clearing can be done easily and absorption of odors or other substances (e.g. trace metals), which accelerate oxidation, is prevented. e oil should be protected from air, light, and fluctuation of temperature above 15ºC. Normally the oil should be kept indoors. If, however, the tanks are stored outdoors, they should be coated with an external lining to prevent extreme changes in temperature. Stainless steel containers are considered ideal for storing. ey have a cone shaped bottom to purge sediments periodically. Nitrogen may be added to the air space. Metallic drums can have a significant negative effect on flavor quality and promote deterioration if not lined with epoxy resins. e storage of olive oil in an iron tank and a polyester-glass fiber (PGF) tank was studied by Perez-Cerezal et al. (1977). Measurements of peroxide values, spectrophotometric constants, and organoleptic evaluation after 10 months showed a significantly more rapid deterioration in the quality of oil stored in the iron container.
