LAUSR

Abstract This work aimed to study the effect of different steps of Spanish-style processing (raw olives, lye treatment, washing, and fermentation) on the oil quality index (Acidity, peroxide value (PV) and extinction coefficient UV at 232 nm and 270), fatty acids, phenols, tocopherols, hexanal and nonanal compounds, and antioxidant activity of the lipid fraction of green Sigoise and Azzeradj cultivar. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used to discriminate the samples according to cultivars and elaboration phases. Most of the variance of the quality parameters and fatty acids was due to cultivars and less for processing. After processing, a substantial loss in the total and individual phenolic compounds was recorded (79.25% and 67.58% for Azzeradj and Sigoise, respectively), but the most significant reduction occurred at lye treatment and washing step rather than the fermentation. Tocopherols were less affected than the phenolic compounds. The antioxidant activity against DPPH radicals of the total lipid fraction of olives was less affected than that of its methanolic extract alone.