Laboratory-scale optimization of olive oil extraction: Simultaneous addition of enzymes and microtalc improves the yield
Article first published online: 8 MAY 2014
© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
European Journal of Lipid Science and Technology
Volume 116, Issue 8, pages 1054–1062, August 2014
How to Cite
Peres, F., Martins, L. L. and Ferreira-Dias, S. (2014), Laboratory-scale optimization of olive oil extraction: Simultaneous addition of enzymes and microtalc improves the yield. Eur. J. Lipid Sci. Technol., 116: 1054–1062. doi: 10.1002/ejlt.201400060
- Issue published online: 4 AUG 2014
- Article first published online: 8 MAY 2014
- Accepted manuscript online: 16 APR 2014 02:34AM EST
- Manuscript Accepted: 8 APR 2014
- Manuscript Revised: 25 MAR 2014
- Manuscript Received: 1 FEB 2014
- the Strategic Project PEst-OE/AGR/UI0245/2011 of CEER and (ii) PEst-OE/AGR/UI0528/2014 of UIQA, research units supported by the national funding of FCT – Fundação para a Ciência e Tecnologia, Portugal
- Cobrançosa Cultivar;
- Galega cultivar;
The aim of this work was to optimize olive oil extraction, at laboratory-scale (Abencor system), from fruits of “Cobrançosa” and “Galega Vulgar” Portuguese cultivars, either in the absence or in the presence of enzymes and natural microtalc. Using a Placket–Burman design to select significant variables followed by a central composite rotatable design (CCRD), Abencor operation conditions were optimized: no water addition in 30 min malaxation and 14% w/w water addition at 50°C in centrifugation. The combined effects of the concentrations of natural microtalc (MT: 0.04–0.46 w-%) and enzyme preparation (E: 0.003–0.117 w-%) added at the beginning of malaxation, on quality criteria, total phenols and chlorophyll pigments concentrations, and on oil extraction yield, were investigated using a CCRD. The results showed that the addition of both an enzyme preparation and natural microtalc could enhance olive oil yield (up to 34% for 0.4–0.5% of microtalc and 0.1% of enzymes for “Galega Vulgar”) without any effect on quality of the obtained virgin olive oil.
Practical applications: Abencor system is the most used laboratory-scale installation in olive oil technology to carry out trials that would be very difficult to perform at industrial scale. This study presents an optimization of the Abencor extraction process, as well as the optimization of extraction with two adjuvants, enzymes and natural microtalc, using two different cultivars. The effect of E and/or MT addition depend on the cultivar. However, an improvement in extractability was always found for both cultivars. This study shows that for “Cobrançosa” olives, considering both olive oil yield and economical aspects, the chosen conditions are 0.05–0.15% of microtalc in the absence of added enzymes. For “Galegar Vulgar” olives, the highest extractability is observed under the presence of enzyme preparation amount higher than 0.10% and microtalc amount of 0.4–0.5%.
The simultaneous addition of an enzyme preparation and natural microtalc could enhance olive oil yield. The use of adjuvants, and their respective amounts, must be adjusted to each cultivar.