Changes produced in extra-virgin olive oils from cv. Coratina during a prolonged storage treatment
A. Baiano, C. Terracone, I. Viggiani, M.A. Del Nobilehttps://doi.org/10.17221/79/2013-CJFSCitation:Baiano A., Terracone C., Viggiani I., Del Nobile M.A. (2014): Changes produced in extra-virgin olive oils from cv. Coratina during a prolonged storage treatment. Czech J. Food Sci., 32: 1-9.
Extra-virgin oil is obtained from olive fruits only by mechanical means. The quality of extra-virgin olive oils is affected mainly by hydrolytic and oxidative reactions. For this reason, the commercial shelf-life is usually no longer than 18 months. In order to investigate the effects of a prolonged storage, olives from cv. Coratina were crushed using a three phase system to produce extra virgin olive oil analysed for sensory and chemical-physical indices, phenolic profile, tocopherol content, and antioxidant activity during a 8-years storage. The oil lost its characteristics of extra-virgin after 6 years of storage, time at which the median of the defects was higher than 0 and free acidity exceeded the limit fixed for this category by the European Regulation whereas the stability against oxidation persisted for a longer period due to the high concentration of oleuropein derivatives. A strong positive linear correlation was observed between the phenolic content and antioxidant activity measured according to the ABTS+. to indicate a noticeable radical scavenging ability of phenolic compounds.Keywords:
aging; antioxidant activity; olive oil; hydrolysis; oxidation; phenolic compounds