Effect of talc addition on the extraction yield and quality of extra virgin olive oils from Coratina cultivar after production and during storage.

An experimental investigation was carried out with the aim to evaluate the effect of talc on the extraction yield and quality of extra virgin olive oils from Coratina olives after production and during storage. A significant effect of talc, added in the malaxer, on both yield and oil quality was observed. The addition of 1% talc lead to a 15% decrease of the residual oil in the olive-pomace, while higher amounts of talc did not determine further significant variations. The use of talc caused also a significant decrease of the peroxide value and tocopherols and a significant increase of carotenoids, chlorophylls, phenols, antioxidant activity and K270, while no influence was detected on free fatty acids and K232. Finally, during storage the differences among the oils were maintained as immediately after their production, with the exception of chlorophylls