Optimization Olive Oil Extraction by Pre-heat Treatment Olive Fruits

Harvesting at high temperatures and bulk transport can negatively influence the quality of olives and lead to undesirable alterations in the extracted oil. Cooling the fruit in the field would be the most logical solution, but it means that the olives arrive too cold at the mill for immediate processing. In this work, the use of warm water in the washing tub to warm up the fruit before grinding instead of flash heat treatment on the paste was assessed in two experiments. In the first one, at the laboratory level, the temperature after milling was determined in three olive cultivars, previously stored at 5 or 10 °C, and then submerged at different water temperatures (25, 30, and 35 °C) for 15, 30, 45, and 60 s. In the second one, two batches of olives were cooled in the field at 5 °C and then conditioned with washing water to obtain a paste at the entrance of the pilot plant malaxer at 27 °C. The temperature of the olives was measured at five points from the discharging up to their entering, as paste, into the malaxer. The results demonstrated the feasibility of the method as the temperature of the ground olives was kept at the desired temperature (28 ± 1 °C). The trials highlight the potential for automating an even more precise adjustment of the temperature of the olives before milling once the washing tub is equipped with a safe heating system.

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Modeling the effect of heat treatment on fatty acid composition in home-made olive oil preparations

Open Life Sciences ◽

10.1515/biol-2020-0064 ◽

2020 ◽

Vol 15 (1) ◽

pp. 606-618 ◽

Cited By ~ 1

Author(s):

Dani Dordevic ◽

Ivan Kushkevych ◽

Simona Jancikova ◽

Sanja Cavar Zeljkovic ◽

Michal Zdarsky ◽

...

Keyword(s):

Heat Treatment ◽

Fatty Acids ◽

Fatty Acid ◽

Olive Oil ◽

Heating Temperature ◽

Virgin Olive Oil ◽

Extra Virgin Olive Oil ◽

Fatty Acid Profiles ◽

Refined Olive Oil ◽

Cross Correlation Analysis

AbstractThe aim of this study was to simulate olive oil use and to monitor changes in the profile of fatty acids in home-made preparations using olive oil, which involve repeated heat treatment cycles. The material used in the experiment consisted of extra virgin and refined olive oil samples. Fatty acid profiles of olive oil samples were monitored after each heating cycle (10 min). The outcomes showed that cycles of heat treatment cause significant (p < 0.05) differences in the fatty acid profile of olive oil. A similar trend of differences (p < 0.05) was found between fatty acid profiles in extra virgin and refined olive oils. As expected, the main differences occurred in monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs). Cross-correlation analysis also showed differences between the fatty acid profiles. The most prolific changes were observed between the control samples and the heated (at 180°C) samples of refined olive oil in PUFAs, though a heating temperature of 220°C resulted in similar decrease in MUFAs and PUFAs, in both extra virgin and refined olive oil samples. The study showed differences in fatty acid profiles that can occur during the culinary heating of olive oil. Furthermore, the study indicated that culinary heating of extra virgin olive oil produced results similar to those of the refined olive oil heating at a lower temperature below 180°C.

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On Some Karian and Hellenic Oil-Presses

The Journal of Hellenic Studies ◽

10.2307/623725 ◽

1898 ◽

Vol 18 ◽

pp. 209-217 ◽

Cited By ~ 5

Author(s):

W. R. Paton ◽

J. L. Myres

Keyword(s):

Olive Oil ◽

Modern Method ◽

Oil Extraction ◽

Asia Minor

This paper is an attempt to interpret certain stones, which have come to light recently on ancient sites in Karia, as parts of ancient oil-presses, on the ground that they are well adapted to fulfil certain purposes which are still essential to the modern native process of oil extraction in that part of Asia Minor and in the adjacent islands. The inference is that the ancient process closely resembled the modern in the principal features which are recounted below.The Modern Method of extracting olive oil consists of the two processes of grinding and pressing.In the most primitive mode of grinding which is still in use, the olives are crushed either on a flat stone by a roller, or in a stone trough by a millstone rolling on its edge. In more modern grinders two mill-stones are used, which revolve in a circular trough, as in the grinding of kaolin or cement. The process of grinding seems never to have varied, except as regards the power which is employed; horses having been substituted for men, and steam for horses. In Algeria and Tripoli the circular trough goes back at least to Roman times.

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