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The influence of semi-hard (C1), hard (C2), and soft whey cheese (C3) immersed in extra virgin olive oil (EVOO) on its oxidative and hydrolytic parameters, fatty acids, and phenolic composition during two months of simultaneous storage was investigated. Accelerated hydrolytic and oxidative degradation was noted in EVOO stored with the immersed cheese compared to control oil. Oxidation indicator (K232), myristic (C 14:0), and trans-oleic fatty acid (C18:1t) exceeded the prescribed limit for the EVOO category in oils stored with immersed C1 and C2, which indicated that standard analytical parameters are ineffective as tools to examine the declared quality and authenticity of such topping oils. The noted changes in fatty acid profile were primarily prescribed to the migration of fats. C1 and C2 influenced a comparable reduction in EVOO total identified phenolic content (−92.1% and −93.5%, respectively), despite having a different content of total proteins and moisture, whereas C3 influenced a slightly lower reduction (−85.0%). Besides the protein profile, other cheese compounds (e.g., moisture, carbohydrates) have been shown to have a considerable role in the development of the EVOO phenolic profile. Finally, compositional changes in EVOO used as a medium for cheese preservation are under significant influence of the cheese’s chemical composition.

The present study investigated the changes in extra virgin olive oil (EVOO) quality, health, and flavour properties during simulated domestic consumption conditions in which the EVOO bottles were reopened daily, thereby gradually increasing the headspace. Quality parameters, phenolic and volatile compounds, and sensory attributes of two monovarietal EVOOs, Istarska bjelica (IB) and Buža (B), have been evaluated every seven days for one month. After storage, the total phenolic content decreased by 12.3% and 17.6% in IB and B EVOOs, respectively, while the total concentration of volatile compounds decreased by approximately 19%. However, the results have shown that no enhanced degradation of phenolic and volatile compounds has been noted in EVOOs stored under consumption conditions compared to the ones stored unopened during the same period, implying that the degradation degree was predominantly attributed to oil aging. The principal component analysis emphasised peroxide value and sensory attributes as parameters that segregated EVOOs under consumption conditions from the fresh and unopened ones. Furthermore, the conditions in which EVOO was consumed in a recommended daily dosage (20 g) during one-month storage did not reduce its phenolic content under the levels required for the EFSA health claim application.

Economic sustainability is often the first to be achieved in small-scale production such as olive growing and olive oil production in Croatia. Tourists occupy an important market for Croatian olive oil in terms of olive oil sales at destinations. To achieve economic sustainability, it is necessary to research the international market of olive oil, and by extension, it is necessary to explore the behaviour, perceptions, and preferences of consumers. Therefore, in this study, field research was conducted on a sample of foreign visitors during their stay at the destination, Istria and Primorje-Gorski Kotar County, Croatia. A significant share of respondents sampled bought olive oil during their stay in Croatia, and the predictor variables for having done so were: extrinsic attribute eco-label on the olive oil bottle and positive perceptions toward characteristics of Croatian olive oil. On the other hand, the frequency of consumption was affected by intrinsic attributes such as olive oil taste, category, and country of origin. Running PCA analysis, three major components were identified: 1) intrinsic characteristic, 2) extrinsic characteristic, 3) price. These components were used for the purpose of market segmentation by applying a two-step cluster analysis. A total of four clusters were identified: 1) “The experts”, 2)“Indifferent consumers”, 3) “Price sensitive” and 4) “The gourmands”. For the sake of developing sustainable business of Croatian olive oil, producers shall find clusters “The experts” and “Price sensitive” to be most suitable. In addition, further efforts to increase the production of eco-certified olive oil should be taken., Ekonomska održivost često je prva koja se želi postići u maloj proizvodnji poput maslinarstva i proizvodnje maslinova ulja u Hrvatskoj. Turisti zauzimaju važno tržište za hrvatsko maslinovo ulje u smislu prodaje maslinovog ulja u destinaciji. Za postizanje ekonomske održivosti potrebno je istražiti međunarodno tržište maslinovog ulja, a samim time istražiti ponašanje, percepcije i preferencije potrošača. Stoga je u ovoj studiji provedeno terensko istraživanje na uzorku stranih posjetitelja tijekom boravka na destinaciji, Istarskoj i Primorsko-goranskoj županiji, Hrvatska. Značajan udio ispitanika je kupio maslinovo ulje tijekom boravka u Hrvatskoj, a prediktorske varijable za to bile su: eko-oznaka na boci maslinovog ulja i pozitivna percepcija karakteristika hrvatskog maslinovog ulja. S druge strane, na učestalost konzumacije utjecali su intrinzične značajke poput okusa maslinovog ulja, kategorije i zemlje podrijetla. Analizom glavnih komponenti, identificirane su tri glavne komponente: 1) intrinzične značajke, 2) ekstrinzične značajke, 3) cijena. Ove komponente korištene su u svrhu segmentacije tržišta primjenom klaster analize. Identificirana su ukupno četiri klastera: 1) “Stručnjaci”, 2) “Ravnodušni potrošači”, 3) “Cjenovno osjetljivi” i 4) “Gurmani”. Za razvoj održivog poslovanja hrvatskim proizvođači maslinova ulja najprikladniji su klasteri “Stručnjaci” i “Cjenovno osjetljivi”. Potrebno je uložiti daljnje napore za povećanje proizvodnje ekološki certificiranog maslinovog ulja.

5 Tablas.- 2 Figuras, The use of reference materials for sensory evaluation of virgin olive oils by tasters, panel leaders and trainers represents a fundamental tool to ensure the performance of panel test in meeting regulatory demands and protect the quality of the product. Herein, a procedure for sensory certification of two, recently formulated, artificial olfactory reference materials (RMs) for winey-vinegary and rancid defects of virgin olive oil is presented. A technical protocol, consisting of different steps aimed at evaluating the representativeness of the sensory defect, determining the detection threshold and estimating stability over time, was applied by six sensory panels involved in the H2020 OLEUM project. Considering the results provided by panels (e.g. in terms of percentages of robust coefficient of variation related to median values of perceived intensities of attributes), the procedure can be considered reliable and able to characterize aroma reference materials that appear to be suitable for their intended use according to the international standards. The possible introduction and use of these new RMs to support selection and training of group of assessors and to increase the control and proficiency of sensory panels can improve the effectiveness of the method by offering advantages such as the reproducibility over time and/or the possibility of purchase or self-preparation, thereby overcoming the lack of availability and year-by-year variation of the current oils used as references., This work is supported by the Horizon 2020 European Research project OLEUM “Advanced solutions for assuring the authenticity and quality of olive oil at a global scale”, which received funding from the European Commission within the Horizon 2020 Framework Programme (2014–2020), grant agreement No. 635690.

Despite the high economic and nutritional value as major positive aspects, olive oil production has an unfavourable side, which is the negative environmental impact caused by the generation of significant amounts of liquid and solid wastes. Therefore, the implementation of sustainable technologies to add value to the olive oil production process is a matter of great interest. This study aimed to review novel solutions dealing with the utilisation of olive oil production by-products while taking into account sustainable waste management options. The most promising technologies for the production of high added value products from olive oil production by-products have been described with a special attention to the sustainable nonthermal technologies for the extraction of bioactive phenolic compounds, and the key findings of such investigations were reviewed. All described technologies are environmentally friendly and show great potential. Nevertheless, further researches are required to optimize and increase their applicability.

The effects of different fertilisation treatments with arbuscular mycorrhizal fungi (AMF) inoculation on AMF root colonisation, fruit yield, nutrient and total phenol contents, volatile compound composition, and sensory attributes of tomato (Solanum lycopersicum L.) were investigated. Mineral, organic, and mineral + organic fertiliser application positively affected tomato yield (35%–50%) and phosphorus concentration (24%–29%) compared with controls. AMF application had a significant impact on the total nitrogen (+9%), manganese (+12%), and hydrophilic phenol (+8%) contents in the fruit. Volatile compounds were affected by the interactive effects of fertilisation and AMF application. The response of tomato fruit sensory quality indicators was relatively modest, with only a few sensory characteristics affected to a lesser extent. Although tomato showed susceptibility to field-native AMF, particular combinations of fertilisation and AMF inoculation were more effective at improving the quality parameters of tomatoes under field conditions applied in this study.

With the aim to investigate the influence of post-harvest olive fruit storage temperatures on virgin olive oil production parameters, composition and quality, Istarska bjelica (IB) and Rosinjola (RO) fruits were stored for seven days at room temperature (RT), +4 &deg, C and &minus, 20 &deg, C prior to oil production. Lower temperatures delayed post-harvest maturation of IB fruits. Theoretical oil content did not change depending on the storage temperature, while the highest oil yield and extractability index were obtained after storage at RT. Chlorophylls decreased in IB-RT and in IB-20. A decrease in the sensory quality of oils was detected after fruit storage at RT and &minus, C, while the refrigeration temperature of +4 &deg, C preserved it. Regarding the content of fatty acid ethyl esters, an increase was observed in IB-RT oils. Storage at RT increased the content of waxes, while the lower temperatures partially suppressed this phenomenon. In oils of both cultivars, storage at +4 &deg, C preserved the concentration of most phenolic compounds at a level more similar to that of the fresh oil when compared to the other two treatments. In the production conditions, when prolonged fruit storage is necessary, refrigeration seems to be the most suitable option.

A set of 334 commercial virgin olive oil (VOO) samples were evaluated by six sensory panels during the H2020 OLEUM project. Sensory data were elaborated with two main objectives: (i) to classify and characterize samples in order to use them for possible correlations with physical&ndash, chemical data and (ii) to monitor and improve the performance of panels. After revision of the IOC guidelines in 2018, this work represents the first published attempt to verify some of the recommended quality control tools to increase harmonization among panels. Specifically, a new &ldquo, decision tree&rdquo, scheme was developed, and some IOC quality control procedures were applied. The adoption of these tools allowed for reliable classification of 289 of 334 VOOs, for the remaining 45, misalignments between panels of first (on the category, 21 cases) or second type (on the main perceived defect, 24 cases) occurred. In these cases, a &ldquo, formative reassessment&rdquo, was necessary. At the end, 329 of 334 VOOs (98.5%) were classified, thus confirming the effectiveness of this approach to achieve a better proficiency. The panels showed good performance, but the need to adopt new reference materials that are stable and reproducible to improve the panel&rsquo, s skills and agreement also emerged.

The purpose of this study was to evaluate the compositional changes (quality parameters, fatty acids, phenolic compounds, and antioxidant capacity) in extra virgin olive oil (EVOO) after cooking treatment in realistic domestic conditions (roasting at 180 °C/60 min) with the addition of typical Mediterranean vegetables (potato, carrot, onion, and mix of those vegetables in equal proportions). Heating increased oil oxidation parameters, while the addition of vegetables during roasting reduced the degree of oil secondary oxidation. EVOO fatty acids have shown strong resistance to heating regardless of the vegetable species added. The initial phenolic composition and radical-scavenging activity of EVOO were significantly altered after roasting resulting in a particular response, depending on the vegetable species used in the treatment. In the presence of vegetables, olive oil total identified phenolic content suffered a major loss, with only 28.27%, 22.00%, 19.87%, and 19.03% of the initial content being preserved after roasting with carrots, potato, onion, and mixed vegetables, respectively. A considerable correlation of both moisture content and pH of the vegetables and the evaluated parameters was found. Obtained results might contribute to understanding the fate and preservation of EVOO beneficial composition in the course of the real cooking conditions.

To investigate the possibilities of balancing the concentrations of phenols and volatiles in virgin olive oil from a late-ripening olive ( Olea europaea L.) cultivar, the effects of ripening degree, malaxation duration, and temperature were investigated. Olives were harvested at three ripening degrees and processed by malaxation at 21/30 °C, for 30/60 min, respectively. The most important phenols and volatiles were generally found to decrease during ripening. The effect of higher malaxation temperature on phenols was dual, with a positive effect on 3,4-DHPEA-EDA and p -HPEA-EDA, and negative on other oleuropein and ligstroside aglycons. An unexpected increase of 1-penten-3-one and ( E )-2-hexenal concentrations as a result of higher malaxation temperature correlated with the increase in key phenols and was a limiting factor in balancing their concentrations, which was confirmed by sensory analysis. Numerous interactions between the factors were established.

Innovative, rapid and environmentally friendly analytical methods are highly desirable in the quality control of the olive oils, thus a growing interest in their deep investigation exists. Despite many methods to assess VOO quality are available at international level, the need of supporting the organoleptic analysis was reported in the call H2020-SFS-14a-2014 and is one of the main objective of the OLEUM project. Specifically, the setting up of rapid instrumental methods could represent a solution for achieving a preliminary screening of a high number of samples and/or for supporting the sensory panels in the discrimination of boundaries samples. In this research, a set of 180 VOOs, sampled during the first year of the OLEUM project, was sensory assessed (EU Reg. 1227/2016) by 6 sensory panels, having different nationality and experience. The headspace volatile profiles of the same set were also analyzed by flash gas chromatography electronic nose (FGC E-nose). The chromatograms were elaborated by multivariate statistical analysis to develop a classification model able to predict the belonging of samples to a specific quality grade. This approach could reduce the daily work of sensory panels which will consequently increase the number and the efficiency of the controls. This work was developed in the context of the project OLEUM “Advanced solutions for assuring authenticity and quality of olive oil at global scale“ funded by the European Commission within the Horizon 2020 Programme (2014–2020, G.A no. 635690).

The aim of this study was to compare quality changes and compositional characteristics (fatty acids, total phenols, sensory profile) during 12 months storage of Buža and Istarska bjelica cv. virgin olive oils clarified by filtration at an industrial scale (filter press equipped with cellulose filters) and those clarified by natural sedimentation and decantation, as well as the influence of filtration of virgin olive oils on sterols and triterpene dialcohols composition. There were no significant differences in hydrolytic deterioration and sensory scores during the whole storage period between filtered and naturally sedimented oil samples. After 6 months, natural sedimentation was more favorable as regards delaying of oxidative deterioration, while filtration provided a more stable sensory profile. As regards total phenols the impact of the clarifying procedure was dependent on cultivar and fruit ripeness degree and it was more emphasized than the impact of storage. Filtration slightly affected the fatty acids composition, but natural sedimentation and decantation had no effect on it. Nevertheless, filtration did not compromise the confirmation of virgin olive oil authenticity according to the fatty acid composition, as well as according to sterols and triterpene dialcohols.

The interactive effects of ripening degree, malaxation duration and temperature on Oblica cv. (Olea europaea L.) virgin olive oil phenols, volatiles, and sensory quality were investigated. Olives were picked at three ripening degrees with International Olive Council indices of 0.68, 2.48 and 4.10, and processed by malaxation at 22 and 30 °C, and at both temperatures for 30 and 60 min. Ripening exhibited the strongest effect, and malaxation duration the weakest. Phenols were generally found to decrease during ripening; however 3,4-DHPEA-EDA and p-HPEA-EDA increased. Similar behaviour was observed for (E)-2-hexenal. Higher malaxation temperature induced an increase in particular important phenols and C6 alcohols, while C6 aldehydes mostly decreased. Interactions between the factors were established, mostly between ripening degree and malaxation temperature: the effect of the latter was most pronounced for ripe olives, especially for 3,4-DHPEA-EDA, p-HPEA-EDA and C6 volatiles. Sensory attributes were generally in agreement with the chemical composition.

Despite having an interesting native olive gene pool and a rapidly emerging olive oil industry, monovarietal extra virgin olive oils (EVOO) from Croatia are relatively unexplored. To investigate the inter-varietal diversity of typical volatile and phenolic profiles of Croatian EVOO, 93 samples from six olive (Olea europaea L.) varieties were subjected to gas chromatography-ion trap mass spectrometry (GC-IT-MS) and ultra-performance liquid chromatography with diode array detection (UPLC-DAD), respectively. Quantitative descriptive sensory analysis was also performed. Analysis of variance extracted many relevant exclusive or partial discriminators between monovarietal EVOOs among the identified volatile compounds and phenols. Successful differentiation model with a 100% correct classification was built by linear discriminant analysis, while the most typical volatiles for each monovarietal EVOO were confirmed by partial least squares discriminant analysis. Diverse typical sensory attributes among the EVOOs were tentatively ascribed to the variations in the composition of volatiles and phenols. It was proven that the approach that comprises GC-IT-MS and UPLC-DAD analysis may provide additional objective information about varietal origin and typicity which successfully complement those obtained by sensory analysis. The approach was characterized as universal in nature, with a significant potential to contribute in strengthening the varietal identities and position on the market of monovarietal and Protected Denomination of Origin (PDO) EVOO.

In order to differentiate the extra virgin olive oils (EVOO) of different origin of purchase, such as monovarietal Italian EVOO with protected denomination of origin (PDO) and commercial-blended EVOO purchased in supermarkets, a number of samples was subjected to the analysis of volatile aroma compounds by both targeted gas chromatography/mass spectrometry (GC-MS) and untargeted profiling by comprehensive two-dimensional gas chromatography/mass spectrometry (GC&times, GC-TOF-MS), analysis of phenols by targeted high-performance liquid chromatography/mass spectrometry (HPLC-DAD-ESI/MS), and quantitative descriptive sensory analysis. Monovarietal PDO EVOOs were characterized by notably higher amounts of positive LOX-derived C6 and C5 volatile compounds, which corresponded to the higher intensities of all the assessed positive fruity and green odor sensory attributes. Commercial-blended EVOOs had larger quantities of generally undesirable esters, alcohols, acids, and aldehydes, which coincided with the occurrence of sensory defects in many samples. Many minor volatile compounds that were identified by GC&times, GC-TOF-MS were found to differentiate each of the two investigated groups. The differences between the groups with respect to phenols and taste characteristics were evident, but less pronounced. The results that were obtained in this study have undoubtedly confirmed the existence of the large heterogeneity of oils that are sold declared as EVOO. It was shown that GC-MS, GC&times, GC-TOF-MS, and HPLC-DAD-ESI/MS analyses have complementary outputs, and that their use in combination has advantages in supporting the results of sensory analysis and objectively differentiating these groups of EVOO.

U ovom je radu ispitan utjecaj filtracije svježih sortnih djevičanskih maslinovih ulja Buže i Istarske bjelice u industrijskom mjerilu na sastav hlapljivih tvari, ukupnih fenola te senzorska svojstva, a uzorci ulja izbistreni filtracijom uspoređeni su s onima koji su izbistreni prirodnom sedimentacijom/dekantacijom nakon šest mjeseci skladištenja. Filtracija je različito utjecala na sastav hlapljivih tvari uzoraka ulja dobivenih od različitih sorata. U ulju sorte Buža je nakon filtracije lagano porastao samo udjel (Z)-2-pentenola, dok se u ulju Istarske bjelice promijenio udjel osam spojeva nakon filtracije (udjeli heksanala, (E)-2-pentenala, (Z)-3-heksenala, (Z)-2-pentenola i (Z)-3-heksen-1-ola su porasli, dok su se udjeli heksil acetata, (E)-2-penten-1-ola i (E)-2-heksen-1-ola smanjili). U svježe filtriranom ulju sorte Buža opaženo je blago smanjenje udjela ukupnih fenola, dok je u ulju sorte Istarska bjelica to smanjenje bilo izraženo, što je uzrokovalo smanjenje intenziteta pikantnosti i gorčine ulja. Sedimentacija/dekantiranje imali su prednost naspram filtracije kod obje sorte, jer su očuvali senzorski profil i udjel ukupnih fenola. Profili arome procijenjeni na osnovi vrijednosti aktivnosti mirisa hlapljivih spojeva i njihovog grupiranja u serije uspoređeni su sa stvarnim senzorskim profilima maslinovih ulja. Dobiveni rezultati mogu imati veliku primjenu u industriji maslinovih ulja tijekom optimiranja tehnologije proizvodnje sortnih djevičanskih maslinovih ulja s očuvanim specifičnim i tipičnim senzorskim svojstvima, ali mogu poslužiti i stručnjacima za izbor metode bistrenja djevičanskih maslinovih ulja prije analize hlapljivih tvari., This study investigates the effect of industrial scale filtration of fresh monovarietal virgin olive oil from Buža and Istarska bjelica cultivars on their volatiles, total phenols and sensory characteristics, and compares the oil samples clarified by filtration with those clarified by natural sedimentation/decantation after six months of storage. Filtration had a different effect on volatiles from the oil samples obtained from different cultivars. In the oil from Buža cultivar immediately after filtration only the amount of (Z)-2-pentenol slightly increased, but in Istarska bjelica the oil filtration affected eight compounds (the amount of hexanal, (E)-2-pentenal, (Z)-3-hexenal, (Z)-2-pentenol and (Z)-3-hexen-1-ol increased, while of hexyl acetate, (E)-2-penten-1-ol and (E)-2-hexen-1-ol decreased). In fresh filtered oil from Buža cultivar a slight decrease of total phenols was observed, while in those from Istarska bjelica the decrease was sharp, causing a decrease in the pungency and bitterness. Sedimentation/decantation had advantages over oil filtration of both cultivars, due to improved effect on the preservation of the sensory profile and the level of total phenols. Tentative aroma profiles based on odorant series obtained from the odour activity values were compared to the actual olive oil sensory profiles. These results could have a high level of applications in the olive oil industry for the optimization of the technology for obtaining monovarietal virgin olive oil with preserved specific and typical sensory characteristics, but also may serve experts to choose an appropriate virgin olive oil clarification method prior to analysis of volatile compounds.

The volatile compounds from virgin olive oil (VOO) are chemical species responsible for its specific flavour. This group of compounds consists mainly of C5 and C6 volatiles that are biogenerated from polyunsaturated fatty acids via lipoxygenase pathway. In this paper the composition of volatile compounds, total phenolic content and sensory profile of monovarietal VOOs from four Dalmatian most common cultivars: Oblica, Lastovka, Levantinka and Krvavica were studied. Fruits from each variety were handpicked at the same ripening stage and processed separately in oil under the same conditions using laboratory oil mill Abencor mc2. All analyzed VOOs were within limits established for extra virgin olive oil category based on chemical parameters. Total phenolic content (TP) of obtained oils were determined spectrophotometrically using modified Gutfinger method and expressed as caffeic acid. The highest TP value was detected in Oblica and Levantinka oils (482.32 mg/kg and 398.85 mg/kg, respectively). Volatile composition of analyzed monovarietal olive oils was determined using headspace solid-phase microextraction with gas chromatography/mass spectrometry (HS-SPME/GC-MS). The most prevalent volatile compound was C6 aldehyde E- 2-hexenal, that contributes to green, fruity, bitter and astringent sensory characteristic of olive oil. The highest value for E-2-hexenal was detected in Levantinka oils (75.89% of total peak area), followed by Lastovka (55.27%) and Oblica (54.86%). In the same time, Lastovka oils had the highest ammount of hexanal (25.72%), C6 aldehide associated with sensory characteristics of green fruitiness, apple and grass. Quantitative descriptive sensory analysis of studied olive oil samples were carried out by a sensory panel using IOC methodology. The sensory profile of Lastovka oil was characterized by medium intensity of olive fruity, green leaves, apple and almonds, strong bitterness and medium pungency. Krvavica oil sensory profile showed the mildest intensity of bitter and pungent of among all analysed oils. Mild to medium fruitiness with grass and ripe apple notes are olfactory characteristics of Krvavica oils.

The aim of this study was to characterize monovarietal olive oils obtained from two less known autochthonous cultivars (Bova and Buža puntoža) on the basis of sterols, triterpene dialcohols and fatty acids profile for the first time, and three monovarietal olive oils obtained from the most widespread autochthonous cultivars (Buža, Istarska bjelica and Rosinjola) grown in Istria, Croatia. β-sitosterol, Δ-5-avenasterol and campesterol were the most abundant sterols in all samples. Campesterol, β-sitosterol and Δ-5-avenasterol most significantly differentiated investigated oils. Bova oil had the highest amount of total sterols (2964 ± 458 mg/kg). Istarska bjelica oil had a peculiar sterol composition with exceptionally low β-sitosterol (67%), high Δ-5-avenasterol (27%) and the highest triterpene dialcohols percentages. Rosinjola and Istarska bjelica oils had the highest monounsaturated fatty acids level, Buža oil had the highest polyunsaturated fatty acids level, while Bova oil showed the highest level of saturated fatty acids. Tested oils obtained from the most abundant cultivars fulfilled all the demands of the current EU regulation required for virgin olive oil regarding sterols, triterpene dialcohols and fatty acids, but Bova and Buža puntoža oil slightly exceeded the upper limit for linolenic acid. Since cultivar is the source of natural variation of sterols, triterpene dialcohols and fatty acids in virgin olive oils, the knowledge about the content of these particular compounds in different monovarietal oils from autochthonous cultivars is important to determine possible disagreements with the demands of the current legislation required for virgin olive oils, in order to anticipate possible false results indicating adulteration.

To investigate if the anecdotal varietal typicity concepts for two monovarietal virgin olive oils (VOO) can be scientifically supported and explained, VOO samples were sorted according to typicity grade and related to sensory and compositional data for volatiles and phenols. Clear inter-varietal, as well as intra-varietal boundaries between more and less typical samples were established by univariate and multivariate statistics. A variety-typical complex odor was related to a complex VOO volatile composition with relatively high amounts of lipoxygenase-derived compounds, accompanied by hydrocarbons, terpenes, and benzenoids. A simpler odor, described mostly as green and typical for the other monovarietal VOO, coincided with the lower amounts of the same volatiles. The intensity of bitterness and pungency was mostly in correlation with the amount of major phenols. Two monovarietal VOOs were clearly distinguished with respect to their variety-typical expression of pungency: the one described as gradually increasing was tentatively related to pinoresinol, while the other, described as immediately strong and burning, was assumed to originate mainly from p-HPEA-EDA. Intra-varietal typicity grades correlated with hedonic liking, as well as with general VOO positive sensory attributes related to key volatiles and phenols.

The possibility of improvement of olive paste extractability by addition of talc or NaCl (1%, 2% and 3% mass ratio in olive paste), or their combinations (“talc 1.5% + NaCl 1.5%” ; “talc 1% + NaCl 2%” ; “talc 2% + NaCl 1%”), was investigated on a laboratory scale. Volatiles in oil samples were determined by headspace solid-phase microextraction with GC-MS, while ortho-diphenols by solid phase extraction and UV-VIS spectrophotometer. Significantly higher extractability of oil (from 25 to 29% compared to control, P < 0.05) was obtained by 3% of talc or NaCl and their combinations in mass ratio 1:2 or 2:1. At 3% addition level, no significant decrease of C6 aldehydes was observed, while significant increase of C6 alcohols (talc or salt) as well as of C5 compounds and terpenes (salt) occurred. Mass ratio of ortho-diphenols in oil was not influenced by talc, while NaCl led to significantly higher values compared to control (by 10-15%, P < 0.05). Practical applications: The influence of processing aids on characteristics of virgin olive oil has mainly been evaluated through the standard chemical quality parameters, while limited information about desirable volatile compounds of thus obtained extra virgin olive oils has been published so far. The results of this research show that NaCl can be used not only as a tool for enhancing the extractability, but also as a means for improving the nutritional value of virgin olive oils from cultivars which generally shows low levels of hydrophilic phenols.

Immediately after extraction from olive fruits, virgin olive oil is a turbid juice with suspended particles of plant tissue and vegetable water droplets, which can deteriorate their quality by facilitating hydrolysis or oxidation of oil. Recently, filtration becomes a standard virgin olive oils production step with the aim of faster product finalisation and shelf-life extension. Filtration of olive oil could influence changes in antioxidant compounds such as phenols, tocopherols, and pigments, as well as volatile substances responsible for pleasant virgin olive oil aroma. In this work the changes of these minor compounds and fatty acids in relation to different filtration systems applied to virgin olive oil are discussed. In addition, influences of several agronomic and technological factors on composition of active compounds of virgin olive oil are reviewed. Moreover, analytical techniques for determination of virgin olive oil active components are pointed out.