Lipochromes, vitamins, aromas and other components of virgin olive oil are affected by processing technology

A stone mill-integral decanter (SD) olive processing line was compared with a traditional stone mill-press (SP) line. a discontinuous method, that, if properly used, yields high-quality virgin olive oils. With "difficult olives" (not easy to process), the SD line yielded oils characterised by: (1) higher contents of pleasant volatiles, tocopherols, beta -carotene, xanthophylls, chlorophylls, pheophytins and waxes; (2) higher values of the 1,2-diglycerides/1,3-diglycerides ratio, integral colour index and chroma; (3) lower contents of phenols, secoiridoids, unpleasant volatiles, aliphatic alcohols, triterpene alcohols and sterols, and (4) lower values of turbidity, brightness and oxidative stability. With "non-difficult olives" (easy to process), whose paste needed to be fluidised with lukewarm water, the SD line yielded oils showing higher contents of pleasant volatiles and tocopherols, lower contents of unpleasant volatiles and comparable contents of phenols and lipochromes. The content of organophosphorus pesticide residues did not depend on the processing method. (C) 2001 Elsevier Science Ltd. All rights reserved.