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Cv. Arbequina fruits were inoculated during one day with suspensions of Aureobasidium pullulans, Epicoccum nigrum or both species (104 spores/g olives), isolated from olive leaves, aiming to increase the phenolic content of the olive oils. Oils were extracted from non-inoculated (control) and inoculated olives, being evaluated for their oxidative stability, and phenolic composition. Compared to the control oils, those extracted from inoculated olives showed higher oxidative stability (+1629%), phenolic acids contents (up to+37%), phenolic alcohols (up to+101%), flavonoids (up to+154%) and secoiridoid derivatives (up to + 12%). These positive effects could be attributed to the hydrolytic activity of enzymes secreted by the studied fungi on the fruit cellular membranes and extracted phenolics, increasing the extractability and, consequently, altering the phenolic concentration. Considering the two fungi species, E. nigrum inoculation had a more significant positive impact on the contents of tyrosol, oleuropein, and ligstroside derivatives, showing an inhibition effect regarding the oleacein formation. Contrary, A. pullulans inoculation mainly resulted into an accentuated increase of luteolin and oleacein contents (3 and 12-times higher compared with control oils, respectively). Overall, no enhanced positive synergetic effect could be attributed to the inoculation with a suspension containing both fungi. The significant changes observed on the phenolic contents, due to the fungal inoculation, allowed the successful discrimination of the four types of extracted oils using an electronic tongue. This device acts as an artificial taste device allowing anticipating an impact at the oils basic taste sensations due to the fungi inoculation., The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for fnancial support by national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020), CEB (UIDB/04469/2020), REQUIMTE-LAQV (UIDB/50006/2020) units and SusTEC (LA/P/0007/2020); to Project “GreenHealth—Digital strategies in biological assets to improve well being and promote green health” (Norte-01–0145-FEDER-000042) and to Project AgriFood XXI (NORTE-01–0145-FEDER-000041), funded by the European Regional Development Fund under the scope of Norte2020 ‐ Programa Operacional Regional do Norte. Ítala M.G. Marx acknowledges the Ph.D. grant (SFRH/BD/137283/2018) pro vided by FCT. Nuno Rodrigues thanks to National funding by FCT-Foundation for Science and Technology, P.I., through the institutional scientifc employment program-contract, info:eu-repo/semantics/publishedVersion

The consumption of carotenoids has several health benefits. It is known that the fortification of olive oils with carotenoids, namely -carotene or lutein, enhanced the oils physicochemical properties, being a possible strategy to increase carotenoids intake. This study showed that a lab-made potentiometric electronic tongue, comprising lipid sensor membranes, could discriminate non-fortified olive oils from those fortified with different levels -carotene or lutein (repeated K-fold cross-validation sensitivities: 87±8%), confirming the impact of the fortification on the oils phenolic contents and sensory sensations. Moreover, the device could, semi-quantitatively, discriminate oils fortified with different amounts (0, 0.05, 0.10, and 0.15 mg/mL) of each carotenoid (repeated K-fold cross-validation sensitivities: 94±9% and 97±7%, for -carotene and lutein, respectively). This could be related to the capability of detecting increasing levels of the carotenoids and to the ability to assess the changes induced by the addition of carotenoids on the total phenols contents and on the intensities of the basic taste sensations. Indeed, satisfactory first- or second-order correlations could be established between the centroids of the first discriminant functions of the linear discriminant models and the carotenoid fortification levels, the total phenols contents, as well as with the sweetness, bitterness, and pungency intensities of the fortified oils (0.865R20.998). The successful qualitative and (semi-)quantitative performance of the electronic tongue may foresee its future application as a practical and cost-effective tool for assessing the impact of the fortification of olive oils with carotenoids at the carotenoids, phenols, and basic taste levels., The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial sup port by national funds FCT/MCTES to CIMO (UIDB/00690/2020) and to CEB (UIDB/04469/2020) units, to the Associate Laboratory SusTEC (LA/P/0007/2020), as well as to BioTecNorte operation (NORTE‐01‐0145‐FEDER‐000004) funded by the European Regional Development Fund under the scope of Norte2020 ‐ Programa Operacional Regional do Norte. Nuno Rodrigues thanks to National fund ing by FCT—Foundation for Science and Technology, P.I., through the institutional scientifc employment program-contract. Mª Carmen Murillo-Cruz thanks to the University of Jaén and Cortijo de la Loma S. L. for her pre-doctoral fellowship and also to the University of Jaén Doctoral School for the stay fnancial support provided., info:eu-repo/semantics/publishedVersion

The effect of olive leaves addition (1%, w/w, cvs. Arbequina or Santulhana), during the industrial extraction of Arbequina oils, on their physicochemical, color, phenolic profile, and sensory characteristics, was studied. Leaves incorporation reduced the primary oxidation (peroxide value by 33% and K232 by 17%) and increased the oxidative stability (19%), with the impact being more pronounced for Arbequina leaves. For these latter oils, leaves incorporation increased the total phenolic content (293±9 mg GAE/kg), which became richer in secoiridoid derivatives (143.7±3.0 mg/kg). Also, only Arbequina oils extracted with their own leaves supported the health claim regarding the protection of blood lipids against oxidative stress (hydroxytyrosol and tyrosol derivatives content greater than 5 mg per 20 g of olive oil). On the other hand, the incorporation of leaves from cvs. Arbequina and Santulhana during extraction enhanced the bitterness (5559%) and decreased the pungency (2533%). Santulhana leaves promoted an increase of the green-fruitiness (5.3±0.5), while Arbequina leaves enhanced the oils sweetness (7.0±0.4). Moreover, a potentiometric laboratory-made electronic tongue was applied, as a taste sensor device, being capable of successfully discriminating Arbequina oils extracted without or with addition of leaves, allowing the identification of (un)deliberated leaves incorporation during oils extraction. Lastly, it was found that the quality and composition of Arbequina oils industrially extracted were leaf cultivar dependent, with the low level of phenolics of control oils promoted by the incorporation of Arbequina leaves., The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020), CEB (UIDB/04469/2020) and REQUIMTE-LAQV (UIDB/50006/2020) units and to the Associate Laboratories for Green Chemistry-LAQV (UIDB/50006/2020) and SusTEC (LA/P/0007/2020), as well as to BioTecNorte operation (NORTE‐01‐0145‐FEDER‐000004) and to Project “GreenHealth—Digital strategies in biological assets to improve well-being and promote green health” (Norte-01–0145-FEDER-000042) funded by the European Regional Development Fund under the scope of Norte2020 ‐ Programa Operacional Regional do Norte. Ítala M.G. Marx acknowledges the Ph.D. grant (SFRH/BD/137283/2018) provided by FCT. Nuno Rodrigues thanks to National funding by FCT-Foundation for Science and Technology, P.I., through the institutional scientific employment program-contract., info:eu-repo/semantics/publishedVersion