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Extra-virgin olive oil is basically used in food, but it can also be used as a source of high added-value components, such as oleocanthal and oleacein. Oleocanthal and oleacein are bioactive compounds with proven activities in the treatment of various diseases. By applying response surface methodology, oils of the Arbequina, Arbosana, and Koroneiki cultivars of super-intensive olive trees have been elaborated, under both irrigation and rainfed conditions. 289 oils have been obtained and 13 parameters per oil determined, which have been grouped into 221 models, that determine extraction performance, quality, and minor components of oils. The maximum extractable olive oil with the current technology is 89.0 ± 3.9%, with the rest remaining in the pomace. Oleacein is the component that most influences the antioxidant capacity of oils; its activity is 5.85 ± 0.33 µmol Trolox/mg. Irrigated Arbequina produces very aromatic oils. Rainfed Arbequina produces less aromatic (18.5 mg/kg of volatile) but with a higher content of phenolic compounds (514.4 mg/kg) oils. Koroneiki produces oils with a very high content of phenolic compounds but low in volatiles. For Koroneiki, the factors that maximize phenolic compounds are: rainfed crops, mill with 4.5 mm sieve, and malaxation at 40 °C for 30 min (1307.2 mg/kg of phenolic compounds, witch 500.0 mg/kg of oleacein, and 174.3 mg/kg of oleocanthal). A method to extract oleocanthal and oleacein from olive oils is proposed, as a way to develop new strategies to improve their functional properties.

The aim of this work is to obtain a balanced commercial virgin olive oil (VOO) using response surface methodology at an industrial level under continuous working conditions. Thus, a factorial design was developed with three factors: sieve size of the hammer mill, temperature, and malaxing time. Forty different responses were modulated, including extraction efficiency, but with special attention to phenolic and volatile compounds because they are responsible for the taste and aroma of VOO. The conditions for malaxing were 22 and 32 °C for 60 and 120 min using 5 and 6 mm sieve sizes. After modeling the responses, the highest extraction efficiency was obtained at 32 °C and 120 min; similar conditions were necessary to obtain the maximum contents of chlorophyll, carotenoid, and phenolic compounds, but the maximum content of volatile compounds was obtained at 22 °C. Therefore, it has also realized a combined optimization of total phenolics and total volatiles.

Three factors for the extraction of extra virgin olive oil (EVOO) were evaluated: diameter of the grid holes of the hammer-crusher, malaxation temperature, and malaxation time. A Box&ndash, Behnken design was used to obtain a total of 289 olive oil samples. Twelve responses were analyzed and 204 mathematical models were obtained. Olives from super-intensive rainfed or irrigated crops of the Arbequina, Koroneiki, and Arbosana cultivars at different stages of ripening were used. Malaxation temperature was found to be the factor with the most influence on the total content of lipoxygenase pathway volatile compounds, as the temperature increased, the content of volatile compounds decreased. On the contrary, pigments increased when the malaxation temperature was increased. EVOO from irrigated crops and from the Arbequina cultivar had the highest content of volatile compounds. Olive samples with a lower ripening degree, from the Koroneiki cultivar and from rainfed crops, had the highest content of pigments.

Olive leaves have become a promising source of phenolic compounds and flavonoids with high added value. Phenolic compounds and flavonoids are important sources of antioxidants and bioactives, and one of the processes used to effectively produce them is extraction via solvents, using aqueous ethanol solutions. To obtain the highest extraction yield per kg of biomass, olive leaves were extracted using a conventional technique (dynamic maceration) and an emerging technology, such as pressurized liquid extraction. Studies of the factors that influence these processes were performed: temperature, leaf moisture content, solvent/solid, and aqueous ethanol concentration were optimized using the central composite and Box-Behnken experiment designs. Pressurized liquid extraction resulted in more efficient oleuropein and luteolin-7-O-glucoside extraction than dynamic maceration. The operational conditions for maximizing the recovery of phenolic compounds and flavonoids and antioxidant capacity were determined to be 190 °C, leaf moisture content of 5%, and aqueous ethanol concentration of 80%.

The malaxation conditions were studied in order to evaluate the composition of secoiridoid derivatives of Picual virgin olive oil using response surface methodology. Secoiridoid derivatives are the most abundant phenolic compounds in virgin olive oil: 3,4-DHPEA-EDA; 3,4-DHPEA-EA; p-HPEA-EDA; p-HPEA-EA. The temperature range studied was 20–60 °C, time 20–60 min, and the talc dosage 0.5–2.5 %. Also, fruit ripening and irrigation management were studied during one season in an orchard of Andalusia (Spain). The content of secoiridoid derivatives increases with increasing malaxation temperature of the olive paste. However, the content of secoiridoid derivatives from oleuropein (3,4-DHPEA-EDA and 3,4-DHPEA-EA) decreases with mixing time, while the content of secoiridoid derivatives from ligstroside (p-HPEA-EDA and p-HPEA-EA) increases. On the other hand, the secoiridoid derivatives from oleuropein increase with increasing maturity index while secoiridoid derivatives from ligstroside decrease in the range studied. Finally, the olive oils from olives cultivated without irrigation have more secoiridoid derivatives than olive oils from olives cultivated with irrigation.