Journal des techniques analytiques et bioanalytiques

Abstrait

Characterization of Extra Virgin Olive Oil Obtained from Whole and Destoned Fruits and Optimization of Oil Extraction with a Physical Coadjuvant (Talc) Using Surface Methodology

Zina Guermazi, Mariem Gharsallaoui, Enzo Perri, Slimane Gabsi and Cinzia Benincasa

The separation of the two components pulp-stone has allowed the development of a more scented product that respects the environment. According to a preliminary study, it was noticed that the destoning process produced a paste containing 67% moisture without resorting to the addition of water. The destoning process presents an ecologically sensitive system as the amount of waste watergenerated was reduced to 0.46 m3/ton of olives. Experimental studies indicate that stone removal before crushing affects to a greater extent the quality of the oil. Indeed the use of stoned olives decreases the acidity by 20%. The specific results of extinctions K232 and K270 confirm that using stoned olives improves the stability of oil since less oxidized compounds (K232 and K270 values 1.69 and 0.11 respectively) were detected. This study also shows that stoned olive oil had a better sensory note than the conventional one and consequently a higher commercial value in the market. Enhanced extraction yield of oil from stoned olives was attained using response surface methodology. Different olive oil extractions were investigated considering three variables: temperature of malaxation, time of malaxation and dose of adjuvant using Central Composite Design. Highest extraction yields were obtained when the temperature and the time of malaxation were respectively 37°C and 35 min. For the proportion of coadjuvant, the optimum dose was found at 1.5%.