New technologies implementation in RIS regions ‘olive oil mills for healthier olive oil extraction.

_{Ofade Consulting, Complejo arquitectónico Palmera central, Bloque 2, Primera Planta, Oficina nº 118;}_{Hmillan@ofadeconsulting.com}_;_{Marta.bazcu@ofadeconsulting.com}
_{Acesur. Carretera de La Carolina, km 29, 23220 Vilches, Jaén.}_{Mmartinez@acesur.com}_{; Jmchinchilla@acesur.com;}_{Lperez@acesur.com}
_{Instituto de la Grasa (CSIC), Campus UPO, 41013 Sevilla, Spain.}_{agracia@ig.csic.es}_;_{mvruiz@ig.csic.es}
_{EnergyPulse Systems, Est Paco Lumiar Polo Tecnológico Lt3, 1600-546 Lisbon, Portugal;}_{duarte.rego@energypulsesystems.com}_;_{marcos.pereira@energypulsesystems.com}_.
_{Department of Drug Science and Technology, University of Turin, Via P. Giuria 9, 10125 Turin, Italy; giancarlo.cravotto@unito.it (G.C);}_{luisa.boffa@unito.it}_(L.B.);_{arianna.binello@unito.it}_{(A.B.); emanuela.calcio@unito.it (E.C.G.); giorgio.grillo@unito.it (G.G.).}
_{Fraunhofer Institute for Process Engineering and Packaging, Giggenhauser Str. 35, 85354 Freising, Germany;}_{matthias.reinelt@ivv.fraunhofer.de}_;_{thorsten.tybussek@ivv.fraunhofer.de}_{; christian.zacherl@ivv.fraunhofer.de}

_*_{Corresponding author: Hmillan@ofadeconsulting.com}

SUMMARY:

New technologies implementation in RIS regions ‘olive oil mills for healthier olive oil extraction (PHENOILS) is a project oriented to give olive oil producers new tools for producing healthier extra virgin olive oils.

Two new extraction technologies, ultrasounds (US) and pulsed electric fields (PEF) are tested with the aim to produce Extra virgin olive oils with high polyphenols. Minor components such as phenolic compounds and tocopherols have a relevant role in health benefits of extra-virgin olive oil.

New extraction technologies were developed and tested in RIS regions whose economies are strongly linked to olive oil production (Spain and Italy). Extraction trials were carried out in lab and semi-pilot scales with the intention of further scaling up to industrial scale in following years.

KEYWORDS:

Extra virgin olive oil, Mill, RIS, Ultrasound, pulsed electric fields.

RESUMEN:

La implementación de nuevas tecnologías en almazaras de regiones RIS para la extracción de un aceite de oliva más saludable (PHENOILS), es un proyecto orientado a ofrecer a los productores nuevas herramientas para producir un aceite de oliva virgen extra más saludable.

Dos nuevas metodologías extractivas, Ultrasonidos y Campos eléctricos pulsantes (PEF), se prueban con el fin de producir Aceites de oliva virgen extra enriquecidos en polifenoles. Los componentes menores como los fenoles y tocoferoles tienen un papel importante en beneficios en salud del aceite de oliva virgen extra.

Las nuevas metodologías de extracción fueron probadas en regiones RIS cuyas economías se encuentran fuertemente ligadas a la producción del aceite de oliva (España e Italia). Los ensayos de extracción fueron llevados a cabo en un laboratorio y a escala semi-piloto para ampliar a escala industrial en los siguientes años.

PALABRAS CLAVE:

Aceite de oliva virgen extra, almazara, RIS, ultrasonidos, campos eléctricos pulsantes.

INTRODUCTION

EVOO health benefits are based on the anti-inflammatory and antioxidative activities of phenolic compounds and tocopherols have a synergistic effect in relation to the antioxidant properties of EVOO (Baldioli et al., 1996) which determine not only the functional quality of the oil but also its oxidative stability, and consequently its shelf-life (Luna et al., 2006).

The tocopherols present in EVOO are transferred directly from the olive fruit without undergoing any transformation. On the contrary the main phenolic components of EVOO, are synthesized during the oil extraction process when different enzymes and phenolic precursors present in the olive fruit come into contact (Romero Segura et al., 2012).

In the last few years, the EVOO productive sector has focused in developing new extraction processes that allow high yields with reduced environmental impact, but above all aimed at obtaining the highest quality oils (Clodoveo, 2013; Kaliogani et al., 2019).

As consequence, in the present manuscript, two promising methodologies (Clodoveo, 2013; Kaliogani et al., 2019) were tested to improve extraction techniques of virgin olive oils: Ultrasounds (US) and Pulsed Electric Fields (PEF).

US and PEF are being evaluated as alternative to the malaxation process (critical step in the extraction of virgin olive oil). Clodoveo et al. (2019) demonstrated that an extra fee of olive oil (usually lost on oil pomace), as well as an improvement in antioxidants content, can be achieved in EVOO thanks to US technology. A greater number of minor components is produced, because US causes a rupture of cellular issues thanks the cavitation phenomenon. (Lohani, Muthukumarappan and Meletharayil, 2016; Amirante et al., 2017).

The second extraction technology studied was Pulsed Electric Fields (PEF). This methodology could be complementary to US (Gogate, 2010). According to previous studies PEF technology provides several advantages such as increasing oil yield.

Two parameters can be determined to investigate the kinetics of the overall reaction balance between autoxidation and antioxidative reactions. Either the oxidation products are monitored, for which typically hexanal is used; or oxygen consumption is monitored during storage in sealed containers. Hexanal is only produced from linoleic acid and can be further oxidised, so while it is a reliable and highly specific marker for rancidity, it is not easily quantified. On the other hand, oxygen consumption can be regarded as a sum marker, also including any other types of possible oxidation reactions. The latter can be directly linked to oxygen transmission through the primary packaging system during storage.

By applying reaction models based on ordinary differential equations, the individual process rates can be separated again to extract the kinetic of the loss of total antioxidative capacity, also taking the oxygen permeation processes via the packaging system into account. In this sense, a secondary objective of the project is to develop a robust mathematical model to predict the evolution of key quality parameters for EVOO such as phenolic content.

MATERIALS AND METHODS
1. Olive Cultivars and extraction methods.

In CSIC-IG, trials have been carried out with Olive fruits in 2 different ripening stages, green, for Arbequina and Manzanilla´s cultivars, and mid-season Manzanilla and Hojiblanca´s cultivar.

In University of Turin, Olive fruits selected were Taggiasca and Mattea in 2 different ripening stages, early and mid-season.

Samples were tested with PEF or US and against control.

Extraction Trials.
1. PEF Trials in CSIC-IG:

Arbequina and Manzanilla fruits were used in the first extraction trial in October and Manzanilla and Hojiblanca were used in the mid-season trial carried out in November. The oil extraction plant used in the trials was an Alfa Oliver olive oil extraction system mod. A0- 500-TOP, with a decanter separator MSPX403- TGP-61 capacity: 250-400 kg olive fruits/h. The PEF treatment was applied with a semiconductor-based positive Marx modulator (Redondo and Silva 2009), model EPULSUS-PM1–10 (EnergyPulses Systems, Lisbon, Portugal), with a maximum pulse voltage of 10 kV, pulse current of 200 A and 3 kW output average power, equipped with a DN25 colinear treatment chamber, with 2.5 cm between the electrodes, integrated in the continuous pilot plant line. The applied electric field was 2 kV/cm in all trials with a 30 µs pulse width at a frequency of 90 Hz. The measured pulse current was approximately 50 A for an applied specific energy of 5 kJ/kg to olive.

Trials in University of Turin (UNITO).

Taggiasca cultivar was tested at both ripening stages (green and half-ripening), for conventional extraction process with a malaxing time of 45 minutes at a temperature of 29 ºC. The extraction was carried out through a three-phase decanter (50 minutes) with the addition of 0.18 L of water for each kg of paste. Finally, the oil was taken to the vertical centrifuge where solid residues and remains of water were eliminated and stored.

For US technique, the study was divided in 2 phases, in the first one the malaxation step was skipped, the temperature was between 25-29 ºC. A power of 600 W at 22 kHz was applied and the paste obtained was stored. The second phase was faster, the temperature was the same but the applicated power was lower (450 W-22 kHz).

To Mattea cultivar, one ripening stage (green harvesting) was used to perform Ultrasounds and conventional extraction technique. In both studies the mixers were working for 30 minutes at 29 ºC, after that, the extraction was carried out through a three phases decanter (20 minutes) with the addition of 210 mL of water. The obtained oil was brought to a vertical centrifuge where the remaining solids and water were eliminated.

In the US test, the malaxing process was eliminated and replaced by US treatment. This test was performed in 2 phases, the first stage was slower (30 minutes), the temperature was between 25-29 ºC and a power of 500 W at 22 kHz. The second stage was carried out at the same temperature, but the power was reduced to 450 W. The paste went through a three phases decanter for 28 minutes, without water addition, then to the vertical centrifuge to eliminate the solid remains.

Shelf-life Study

Optimization of the Shelf-life study and preliminary data to develop a predictive model were carried out using four commercial oils, from different RIS countries, obtained in the previous season, 2019-2020.

Once the oils were obtained with the new extraction techniques, a study of their shelf life was achieved.

A simplified model of the autoxidation- and antioxidative reactions was applied to investigate the interaction of packaging properties on the shelf life and the antioxidative capacity of the oils. The reaction model was developed by describing the complex system of equilibria and irreversible reactions during the autoxidation (Labuza et al.) as a simplified net reaction only considering the primary educts and products. Therefore, the inherently exponential behavior of the radicalic autoxidation was preserved by introducing “radicals” [X] as a hidden sum variable describing the various positions of unpaired electrons in the chain reactions, most notably as radicalic hydroperoxide groups. Another advantage of this approach is the reduction of the free parameters of the equation system. The here applied scheme can be executed with only 3 kinetic constants k_1-3, i.e., for the oxidation, termination and antioxidative radical capture, respectively. The reaction scheme (equ. 1-4) and resulting ordinary differential equations (equ. 5-9) .

The oxidation rate R_Ox is formally 3^rd order between the oxygen concentration in the oil [O₂], the concentration of oxidizable carbon double bonds [F] and the unspecified radicalic species [X] and is balanced by the radicalic termination reaction R_X and antioxidative reactions R_A. The permeation rate R_Perm governs the packaging properties as the oxygen transmission rate (OTR). The antioxidative capacity is parametrized by [A]. Equations 5-9 are the ordinary differential equations of the model. They can be solved numerically by ode15s-Solver in MATLAB. The factor 2 in equation 8 is the multiplication factor for the radical species and determines the exponential characteristic of the model.

The initial concentration of oxidizable carbon double bonds in olive oil can be estimated from the fractions and type of fatty acids (oleic acid 70%, linoleic acid 7%). The initial antioxidative capacity (in the modelling context as the capacity to disable free radicals) is estimated from the combined polyphenol and tocopherol content with each molecule being able to bind one radical. As the mechanism for tocopherols is almost catalytic (oxidized stable tocopherol can be recovered by H-donors such as vitamin C), this is a highly parametrized approach and only relative changes should be considered carefully. A more detailed approach can only be applied for more dedicated experimental data resolving additional parts of the complex reaction network. The steep decrease of oxygen in the accelerated vial test is used as a benchmark set and the kinetic constants are chosen such that the simulation agrees sufficiently to the benchmark data. It must be noted that the slope of the oxygen concentration depends non-linearly on the initial radical concentration and the ratio between the termination constant k2, the oxidation constant k1 and on k3. Therefore, the equation system requires a detailed mathematical multi-variate fitting procedure to determine a possible global minimum to the data sets. The manual fit performed here on selected datasets can only capture the rough characteristics of the experimental data and is not yet finalized.

Accelerated storage test.

1.0 g of oil was weighted into PS petri dishes and mixed with 0.60 g copper powder with a particle size of less than 75 µm (Sigma-Aldrich, Germany). The sample was placed into a gas tight cell with a total volume of 130 ml, equipped with gas tight ventiles. The cell was gastight closed and stored at 30 °C under exclusion of light. After conditioning the pressure inside the cell was measured by a manometer (GDH 12 AN, Greisinger, Germany) via a ventile. The measurements were performed in regular periods. The amount of consumed oxygen was calculated by the loss of pressure during the observed period. Before reaching a total consumption of oxygen, the cell was flushed with fresh air and storage was continued.

d Analytical methods:

Extraction and analysis of phenolic compounds

EVOO phenolic compounds were isolated by solid phase extraction (SPE) on a diol-bonded phase cartridge (Supelco, Bellefonte, PA) based on the method by Mateos, et al., (2001) and using p-hydroxyphenyl-acetic and o-coumaric acids as internal standards. For Manzanilla and Arbequina cultivars, phenolic compounds were analyzed by HPLC on a Beckman Coulter liquid chromatography system equipped with a System Gold 168 detector, a solvent module 126, and a Waters column heater module following a previously described methodology (Pérez et al., 2014). A Superspher RP 18 column (4.6 mm i.d. x 250 mm, particle size 4 µm: Dr Maisch GmbH, Germany) at flow rate 1mL min⁻¹ and a temperature of 35 ºC was used for all the analyses. Tentative identification of compounds was carried out by their UV-vis spectra and later confirmed by HPLC/ESI-qTOF-HRMS on a liquid chromatograph Dionex Ultimate 3000 RS U-HPLC liquid chromatograph system (Thermo Fisher Scientific, Waltham, MA, USA) equipped with a similar column and elution program. Mass spectra were acquired in MS full scan mode and data were processed using Target Analysis 1.2 software (Bruker Daltonics, Bremen, Germany).

For Taggiasca and Mattea cultivars the analysis were performed according to COI method. For HPLC application, 0.2% H₃PO₄ (A) and 1:1 MeCN/MeOH (B) were used as mobile phases, the monitored wavelength was 280 nm, while three-dimensional data were acquired in the 200–400 nm range (gradient: 0 min, 4% B; 40 min, 50% B; 45 min, 60% B; 60 min, 100% B; 70 min, 100% B).

Analysis of tocopherols

For Manzanilla and Arbequina cultivars, the analysis is based on the official IUPAC method (1992) for tocopherols slightly modified. For this purpose, 50 mg of oil were dissolved in 1 mL of hexane containing -tocopherol acetate (0.5 mg/mL) as internal standard, filtrated through 0.45 μm nylon and analyzed by high-performance liquid chromatography in a Beckman-Coulter system equipped with a Tracer LiChrosorb Si 60 column (250 mm, 4.6 mm, 5 μm) (Tecknokroma, Barcelona, Spain) and a Jasco FP-1520 fluorescence detector

(JASCO Corporation, Tokyo, Japan). For quantification, the internal standard and the response factors calculated for each of the tocopherols (α, β and γ) were used. Data were expressed as mg of tocopherol per kg of oil.

For Taggiasca and Mattea cultivars the analysis is based on the official IUPAC method (1992). They were performed on a Waters binary pump 1525 linked to a 2998 PDA (Waters), using a Spherisorb 5µ Silica column (250 mm, 4 mm, 5 µm; Waters). (±)-α-Tocopherol, rac-β-tocopherol, (+)-γ-Tocopherol, (+)-δ-tocopherol were purchased from Merck. For the IUPAC method, the mobile phase was a 0.5:99:5 propan-2-ol/hexane mixture, the monitored wavelength of the UV detector was 292 nm.

Characterization:

Related with the study of physic-chemical components evolution´s of oils through time, it was monitored based on acidity, moisture, peroxide index, rancimat, anisidina index, K268 and K270 (Standard 2568/91 UE).

Sensory evaluation

The organoleptic assessment of the EVOOs was carried by an accredited panel (UNE-EN-ISO/IEC 17025) using the standard COI/T.20/Doc. No 15/Rev.10 (IOC, 2018). Trained assessors tested the samples to assess the oil quality by determining the levels of positive attributes, such as fruitiness and pungency, and levels of negative attributes, such as rancid and fusty defects. The sensory assessment results are expressed as the median of defect and the median of fruity. Subsequently, the EVOOs were graded by comparing their median values with the reference ranges specified in the commission regulation (EEC) No 2568/91 (European Union, 1991).

RESULTS AND DISCUSSION
1. Yield and content of phenolic compounds and tocopherols:
  1. CSIC-IG:

Early season trial- Installation of PEF equipment seemed to be perfectly compatible with the Alfa Laval oil extraction System not affecting its standard working flow. The unique parameter affected by the PEF treatment was a temporary and minor increase in the paste temperature after PEF treatment (average 1.5ºC).

To evaluate the effect of PEF optimum conditions, were selected for Control extraction of Manzanilla oil (25ºC and 90 min malaxation) while only 45 min of malaxation were applied during PEF extraction. In these conditions, yield obtained in PEF extraction was 1 percent point lower than the control one. Very low yields were obtained in Arbequina’s extraction, due to poor conditions of 2020´s season. A slightly higher content was found in Manzanilla PEF oil. However, no significant differences were found in Arbequina´s oils. In a similar way, no significant differences were observed in the tocopherol content of the oils obtained. According to the sensory evaluation Manzanilla oil was classified as “extra” and Arbequina was classified as “virgin” with a winey defect (table 1).

As consequence, no positive results were obtained with Arbequina cultivar, with lower industrial yields (around 9%), nevertheless data suggest that PEF could help to reduce malaxing time.

Mid-season trial, two malaxing conditions, 0 and 30 min, were applied to PEF and Control extractions. Yields obtained with malaxing time 0 were lower for cultivars tested, and no significant differences were found between control and PEF samples. On the contrary, with 30 min of malaxation significantly better results were obtained for PEF extractions compared to control ones, increasing 0.8 percent points (corresponding to an increase of 7.5%) manzanilla´s cultivar yield and 1.1 percent points (corresponding to an increase of 11.5%) in Hojiblanca´s cultivar.

In extractions carried out with malaxing time 30 min, PEF oil´s yields were higher than their respective controls (about 7.5% and 11.5%, for Manzanilla and Hojiblanca respectively). It suggests that PEF could have positive effect on Hojiblanca and Manzanilla cultivars.

It seems reasonable that the use of PEF technology must be specifically evaluated in each olive cultivar and different characteristics of the olive fruits (ripening stage, water content, etc.)

The phenolic content of Hojiblanca oils were extremely low, however a 26% higher content was found in Hojiblanca PEF “0 malaxation” in comparison with the control. The same way, in Manzanilla oils extracted with PEF (0 min and 30 min) a slight increase in terms of phenolic content was observed against the control. An increase of 7.4% and 9.1% respectively for 0 min and 30 min of malaxation.

However, statiscally significant (P≤0.05) increases were observed for some of the most bioactive phenolic compounds such as Oleacin, Oleocanthal and hydroxytirosol acetate. These results suggest that the application of PEF technology could improve the phenolic content in industrial oils of Manzanilla cv.

Due to the low quality of Arbequina oils obtained, only Manzanilla and Hojiblanca oils were selected for shelf-life study and 30 malaxation time, due to best results.

No significant changes were observed along the storage in the total phenolic content of the oils. The phenolic content of Manzanilla oils extracted with PEF remained higher than control oils along the storage. No significant changes were observed in Arbequina and Hojiblanca.

University of Turin (UNITO):

There is not significant difference in terms of olive oil characteristics, oil yields and tocopherols. Nevertheless, an increase of 15% of polyphenols in US-assisted process than conventional one (table 2). On the other hand, the US- assisted process enable less energy consumption as well as less OMWW produced.

Concerning organoleptic assessments, some differences were found between half ripening and green Taggiasca oil samples. Both oils from Taggiasca half ripening, were classified as VOO, and green Taggiasca as EVOO. Taggiasca green obtained by US had green fruitiness with hints of almond and it was somewhat reminiscent of half ripening Taggiasca samples and Green Taggiasca control had a more distinctly green fruitiness.

Characterization.

Characterization of all oils obtained and their evolution, in 2020´s annuity is detailed on tables 3 and 4.

Some differences are observed in the evolution of each oil due to different cultivars treated and different maturation stages of the cultivar used.

Most of data suffer natural degradation through time. Oxidation´s evolution in different oils is clearly demonstrated with Rancimat, k232 and k270 parameters.

Sensory evaluation

Manzanilla oils kept the “extra” category along the full storage period. Curiously, the intensity of the fruity attribute at the end of the accelerated storage was higher in Manzanilla PEF than in Manzanilla Control. The organoleptic defects of Arbequina oils increased along the storage and according to panel test both samples, control and PEF (table 1).

Shelf-life data
Polyphenols from oils obtained at the first ripening stage in CSIC-IG had natural degradation, in relation to tocopherols, any significant difference.
Accelerated conditions of climatic chamber affected to the sensorial characteristics of the oils, only catalogued as EVOO, Arbequina´s oil after 45 days.Concerning samples of US treatment, Mattea cultivar possess the highest variability through shelf-life study. Related with tocopherols, US samples showed higher devaluation.In Taggiasca phenols ‘degradation, no deviation can be noted between benchmark and US samples.In the tests carried out in CSIC-IG was observed an increase of the phenolic content of both extractions realized in Manzanilla cultivar, although there wasn´t clear evidence that the same happens with other cultivars. It is accepted that Pulsed Electric field is an effective alternative which depends on the cultivar and stage maturation ripening of the olive, which influence in the final phenolic content of the olive. Manzanilla cultivar was the best option in this study, in early ripening with higher phenolic content.Pulsed Electric Field produces an accelerated treatment of stabilization of the multiple isomers formed by hydrolysis from phenolic glycosides during fruit crushing, so the amount of the main secoroid derivates observed is higher in PEF than in oils control obtained. About the amount of Oleocanthal and Oleacin in Manzanilla´s cultivar, is observed in PEF technique that the initial amount is higher and stabilised during the study.Its study clarified that the climatic conditions that the EVOOs were subjected, weren´t good enough for its study of evolution of the total antioxidants about the predictive mathematical model, suggesting new extreme conditions that would be implanted in the new annuity of the project to obtain better results.

iii. Fraunhofer: Oxygen uptake during accelerated storage.

The simplified reaction model was manually benchmarked with experimental data. The experimental data clearly shows the exponential drop of the oxygen concentration after 30 days under accelerated conditions.

The observed oxygen uptake the olive oil under atmospheric conditions at 30ºC did show in experimental data the corresponding progression as the simplified model of the autoxidation- and antioxidative reactions. Therefore, the model can simulate the oxidation reaction of the olive oils by the given input values. PEF extraction showed no significant change in the composition of the extracted oil and therefore no difference in the behaviour during storage.

However, the partially benchmarked model of the radicalic autoxidation/antioxidation reactions could be applied to identify possible acceleration options for accelerated testing procedures. The accelerated experimental be used as a fix-point for obtaining some of the model constants with an acceleration factor of approximately 20. Furthermore, the model constants can be also scaled down to realistic storage conditions in terms of storage temperature when each reaction constant is replaced by an Arrhenius-scaling of the form k . Especially for the simulation of the gas exchange via the packaging system, the known temperature scaling of the oxygen permeability in the packaging material or the advective transfer rate via pinholes can be applied, providing a tool to re-scale accelerated storage tests.

However, there are still some crucial assumptions in the current model, most notably the initial radical concentration and termination reaction constants, which cannot be directly measured. Hence, further indirect benchmarking of those free parameters is required.

In its current form, the model was used to relatively compare the tested oil variants and production methods in a realistic scenario. It was found, that in addition to the leak rate of the packaging system (i.e., cap seal of the glass bottle), the initial oxygen in the head space and oil after closing the bottle had a pronounced influence on the shelf life. Shelf life, in this context, can be defined by a combination of the degree of oxidation and the remaining antioxidative capacity. Oxygen from the production and initial packing and from leakages of the packaging system increase the degree of oxidation and decrease the concentration of antioxidants. As implemented in the model, equations, both rates are coupled.

Hence, the greatest potential (as identified by simulations) for preserving the antioxidative system as long as possible (under dark storage conditions) is:

To ensure a minimum leak rate of the cap.

Minimizing the oxygen in the oil head space after production (i.e., by maximized filling level or flushing with inert gas)

Maintaining a high concentration of possible H-donors to partially regain oxidised polyphenols and tocopherols.

CONCLUSIONS
- EVOO and extraction techniques conclusions:

In reference to oils tocopherols content, no significant modification has been observed neither along cultivars nor ripening stages nor extraction techniques. No defect and unusual flavour were detected by panellists. By contrast in Manzanilla cultivar, the intensity of the positive attributes, was significantly higher in PEF sample than in conventional extraction process sample.

Use of PEF didn´t influence the sensory quality of the oils, neither their classification. The high fruity intensity was detected thanks to some complementary analyses. Moreover, PEF technique enabled a yield increase between 7.5 to 11.5% in the EVOO production without any negative consequence for the oil.

It can be concluded that PEF extraction technology doesn´t prevent formation of phenolic and volatile compounds along all the extraction process, probably facilitating the extraction and solubilisation of the substrates and enzymes of both biosynthesis processes.

The development of dedicated ultrasonic reactors and the design of well-suited operative conditions enabled UNITO to combine the objective to produce an EVOO of high nutritional quality, characterized by pleasant organoleptic properties and high yields.

Concerning organoleptic assessments, some differences (presence of defects) were found between the half ripening and green Taggiasca oil samples. All

Green Taggiasca oil samples were classified as EVOO with medium fruity, bitter, and pungent attributes. Green Taggiasca oil obtained by US treatment had a green fruitiness with hints of almond and it was somewhat reminiscent of half ripening Taggiasca samples, while Green Taggiasca Control oil had a more distinctly green fruitiness.

Light fruity, bitter, and pungent attributes were found in both green Mattea oil samples (median <3.0), both classified as EVOO.

Only high quality EVOO is rich of healthy natural components that allow to advertise health claims. This EVOO property can be used as a tool to improve the market value of the product enabling to differentiate the trade category named EXTRA. The promotion of the use of health claims authorized by EU can help the consumers to recognize the different quality of olive oils and distinguish the premium quality products and the standard quality products. An innovative communication campaign based on innovative languages and persuasive messages will help the consumer to make consciously their choice.

The main physicochemical parameters of the oils that showed an evolution in the oxidation during storage at climatic chamber were: Rancimat, K232 y K270.
- Mathematical model conclusions:
- Its study clarified that the climatic conditions that the EVOOs were subjected, weren´t good enough for its study of evolution of the total antioxidants about the predictive mathematical model, suggesting new extreme conditions that would be implanted in the new annuity of the project to obtain better results.

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PHENOILS. New technologies implementation in RIS regions’ olive oil mills for healthier olive oil extraction

New technologies implementation in RIS regions ‘olive oil mills for healthier olive oil extraction.

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