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A capacity to determine the provenance of high- value food products is of high scientific and economic interest. With the aim to develop a tool for geographical traceability of Croatian extra virgin olive oils (EVOO), multielement composition and 13C/12C isotope ratio in EVOO as well as the geochemistry of the associated soils were analysed in samples collected from three regions along the Croatian Adriatic coast. Soil geochemistry was shown to influence the transfer and elemental composition of EVOO. The most discriminating variables to distinguish EVOO from different regions were S, Mo, Rb, Mg, Pb, Mn, Sn, K, V and δ13C. The predictive models achieved high sensitivity and specificity, especially when carbon isotope composition was added. The results suggest that interregional geographical traceability of Croatian EVOO is possible based on matching their multielement composition with that of the soils in the provenance area.

Aims A potential of rare earth elements (including yttrium) (REY) accumulation in olives is increasing due to enhanced use of REY in human activities. REY transfer to extra virgin olive oil (EVOO) is little studied, and characterising the relationships between soil properties and REY concentrations in olive leaves, pomace and EVOO can enhance our understanding of soil-plant interactions. Methods Three different soil types (reclaimed karst, rendzina and cambisols), with the sum of REY concentrations (54–364 μg g−1) among the highest in European soils, were characterized for their pH, organic carbon, total carbonates and the applied agronomic practice. Aluminium, calcium, iron, phosphorus and REY were determined in soil (total and plant-available), olive leaves, pomace and EVOO. Results REY were mainly excluded from plant uptake and only small amounts of REY were transferred to leaves (0.2– 652 ng g−1), pomace (0.001–10 ng g−1) and EVOO (

Outstanding organoleptic characteristics make sweet cherries one of the mostpopular seasonal fruits, as it has numerous health benefits making it an increasinglyimportant part of the human diet. This study was conducted to evaluate various phys-icochemical properties of nine introduced and five local sweet cherry cultivars. RanaStonska had the lowest measured content of phenols, flavonoids, and anthocyanins, Bigarreau Burlat had the highest amount of phenols and flavonoids, and Garnet the highest measured anthocyanins content. Potassium content was lowest for Sunburstand highest for Rana Stonska. PCA analysis allowed the discrimination of two quitedifferent cultivars in relation to all assessed, Ranka and Isabella, since Ranka rankedthe lowest in terms of fruit weight, thickness, volume, geometric mean diameter, andsurface area of the fruit. Isabella cultivar stood on the opposite end of the range, rank-ing the highest in all data categories

Pomegranate (Punica granatum L.) is a nonclimacteric fruit sold fresh as whole fruit or arils (fleshy seeds). It is also used for the production of juice, wine, and syrup. Pomegranate is popular due to its numerous health benefits. In the United States, it is grown primarily in California and other semi-arid regions, with Wonderful being the most widely grown cultivar. However, preliminary research has shown that ‘Wonderful’ produces low yields in Georgia, thus indicating the need to identify cultivars better suited for warm and humid conditions, such as those of the southeastern United States. The objective of this study was to determine the physical and chemical quality attributes of pomegranate cultivars grown in Georgia. Pomegranate fruit from 40 cultivars were harvested during 2012 to 2017. Individual fruit weight varied from 124 g for ‘Utah Sweet’ to 631 g for ‘C1’. The total fruit weight percentage accounted for by fresh aril weight (aril fraction) ranged from 22% for ‘C8’ to 70% for ‘JC’. Individual aril weight ranged from 174 mg for ‘Utah Sweet’ to 638 mg for ‘Cloud’. Across cultivars, individual fruit weight increased linearly with the increasing number of arils. Aril color varied from white to deep red. The arils L* value ranged from 15.7 (dark arils) for ‘Crown Jewel’ to 46.1 (light arils) for ‘Utah Sweet’. The a* values ranged from 0.6 (white arils) for ‘Cloud’ to 20.5 (red arils) for ‘Crab’. The b* values ranged from 8.7 for ‘DJ Forry’ (from a store) to 62.5 for ‘R9’. The Chroma* values ranged from 13.4 for ‘Cloud’ to 24.3 for ‘Crab’. The hue° values ranged from 29.7 for ‘Wonderful’ (from a store) to 87.1 for ‘Cloud’. Rind color was related to the color of the arils; high a* values in the rind and arils were associated with the red color. The fruit juice content ranged from 174 mL·kg−1 fruit for ‘Utah Sweet’ to 638 mL·kg−1 fruit for ‘Cloud’. Cultivars varied from tart to sweet. The fruit soluble solids concentration (SSC) ranged from 10.8% for ‘Sin Pepe’ to 16.4% for ‘Crown Jewel’. Fruit titratable acid (TA) ranged from 0.27% for ‘Sin Pepe’ to 6.20% for ‘Utah Sweet’. The juice maturity index measured as the SSC/TA ratio ranged from 1.9 for ‘Utah Sweet’ to 39.5 for ‘Sin Pepe’. The juice total phenols (measured as gallic acid equivalents) ranged from 463 mg·L−1 for ‘JC’ to 2468 mg·L−1 for ‘Wonderful’ (Georgia). Trolox equivalent antioxidant capacity values of juice ranged from 10,001 µM for ‘King’ to 59,821 µM for ‘I11’. Cupric reducing antioxidant capacity values in juice ranged from 7471 µM for ‘Azadi’ to 20,576 µM for ‘Wonderful’ (Georgia). Juice total anthocyanins varied from 1.7 mg·L−1 for ‘R19’ to 50.0 mg·L−1 for ‘Wonderful’ (Georgia). Pomegranate cultivars showed large variability in physical and chemical attributes. Such pomegranate variability represents opportunities for breeding, for the retail market, and for the development of different products by the food industry.

The quality parameters, a variety of microcomponents, and the sensory characteristics of Oblica and Leccino cv. virgin olive oils (VOOs) were evaluated before and after filtration process adopted in order to estimate the individual varietal compositional changes. The dynamics of the formation of hydrolytic and oxidative changes in unfiltered (UF) and filtered (F) oils was asses by comparing level of free fatty acids (FFA), peroxide value (PV), and spectrophotometric indices periodically during 1 year of oil storage. An analysis of phenolics, tocopherols, and fatty acids was determined by chromatographic (HPLC and GC) and spectrometric methods, oxidative stability by Rancimat method while sensory analyses of obtained olive oils were performed by a trained professional panel. Single monovarietal VOO loses phenols in different rate with the applied filtration. Total secoiridoids decreases significantly in "Oblica" VOOs while no changes in their concentrations were found between unfiltered and filtered "Leccino" oils. Intensity of desired sensory properties decreases with filtration. In "Leccino" VOOs decrease of oxidative stability was more pronounced. After 12 months of storage, filtered "Leccino" VOOs had significantly lower FFA values than observed for the unfiltered counterparts. Further, there were no significant changes in PV and K270 values between unfiltered and filtered oils of both studied varietal oils. Storage time influenced more studied quality parameters than filtration, during which PV of unfiltered oils faster deteriorate. The highest changes between stored and corresponding fresh samples were exhibited in unfiltered "Oblica" VOOs. PRACTICAL APPLICATION: Quality enhancement of olive oil is constantly being done professionally and scientifically. The information provided in this study can be used in the industry of olive oil for improve the phenolic content, oxidative stability, and the sensory quality of virgin olive oils. The findings of stability test could be guidelines for mindful leading of the oil finishing up to bottling.

Olive leaves are a highly available by-product from table olive and olive oil production. They are nowadays strongly valuable for their major bioactive compounds and their beneficial effects. To determine the differences between two Croatian domestic (Lastovka, Oblica) and two introduced (Leccino, Frantoio) cultivars, physical and chemical analysis of olive leaves were performed: surface area, color variability, total phenolic amounts, and essential oil volatile profiles were analyzed at three harvest periods. All cultivars greatly differed in surface area, with cv. Lastovka being the smallest. Color variability resulted in an overall decrease in darkness and amounts of green and yellow that could be attributed to a decrease in photosynthetic demand and chlorophyll content. The highest amount of total phenolic content occurred in the summer months, followed by a reduction until October. Essential oils volatiles were determined by GC-MS and showed great diversity not only amongst cultivars but also between harvest periods, with overall 45 compounds identified. Principal component analysis distinguished domestic cultivar Oblica from the other observed cultivars, mainly due to its essential oil volatile fingerprint. Compounds that differentiated cv. Oblica were aldehydes ((E,Z)-2,4-heptadienal, (E,E)-2,4-heptadienal, decanal), ketones ((E)-β-damascone, dihydrodehydro-β-ionone), sesquiterpenes (cyclosativene, α-copaene, α-muurolene) and saturated hydrocarbons (tetradecane, hexadecane). Essential oil volatile fingerprint attributed the highest to the biodiversity of domestic cv. Oblica through all three harvest periods.

The authenticity and typicity of monocultivar oils and knowledge of the changes that environmental olive growing conditions bring to naturally present antioxidants and sensory attributes of virgin olive oils (VOO) are important for quality and safety improvement. This study delivers a comprehensive evaluation of the factors affecting phenolics, fatty acid composition and sensory characteristics of cultivars Oblica and Leccino VOOs throughout ripening season at two distinct olive growing environments during three consecutive crop years, and ranks the importance of each factor. Specified parameters were significantly influenced by olive growing environmental conditions. At the colder location of higher altitude, both cultivars gained higher amount of stearic, linoleic and linolenic fatty acids, as well as a higher proportion of phenolic compounds, but lower amounts of oleic fatty acid. At the warmer location of lower altitude, both cultivars had oils with lower level of fruitiness, bitterness and pungency. Analysis of the main components showed that VOOs were primarily differentiated by the cultivar, then main groups were divided with regard to the growing site, while harvest period affected the biosynthesis of natural VOOs antioxidants but had the least impact. These results reveal that the composition of fatty acids, phenolic content and sensory profile are predominantly characteristics of a cultivar.

The olive fruit fly (Bactrocera oleae Rossi) is the primary insect pest in all olive-growing regions worldwide. New integrated pest management (IPM) techniques are needed for B. oleae to mitigate reliance on pesticides used for its control which can result in negative environmental impacts. More effective lures for monitoring olive flies would help to know when and where direct chemical applications are required. The aim of this research was to find new, more effective methods for B. oleae detection and monitoring. Twelve insect-associated yeasts were selected and tested as living cultures in McPhail traps for the attraction of olive flies. Certain yeasts were more attractive than others to B. oleae, specifically, Kuraishia capsulata, Lachancea thermotolerans, Peterozyma xylosa, Scheffersomyces ergatensis, and Nakazawae ernobii, than the industry-standard dried torula yeast (Cyberlindnera jadinii, syn. Candida utilis). The attractiveness of dry, inactive (i.e., non-living) formulations of these five yeasts was also tested in the field. Inactive formulations of K. capsulata, P. xylosa, N. ernobii, and L. thermotolerans were significantly more attractive to B. oleae than commercially available torula yeast. Green lacewing, Chrysoperla comanche (Stephens) (Neuroptera: Chrysopidae), adults were incidentally caught in traps baited with the live yeast cultures. This is the first field study that compares olive fly attraction to yeast species other than torula yeast. Commercialization of yeasts that are more attractive than the torula standard would improve monitoring and associated control of the olive fruit fly.

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.

Analysis of elements in Extra Virgin Olive Oil (EVOO) is challenging due to the complex oil matrix as well as very low element concentrations in oil. We postulate that inadequate sample preparation (in particular, the presence of pomace residue in oil) may significantly contribute to variations in EVOO element concentrations. In order to confirm this hypothesis, EVOO and pomace samples were analysed for content of 29 elements by ultrasonic acid extraction and ICP-MS detection. Comparative analyses of non-centrifuged and centrifuged EVOO samples confirmed significant influence of pomace residues on element concentrations. Ranges of macronutrients (25–286 ng g−1), micronutrients (0.3–1.1 ng g−1) and trace elements (0.001–0.2 ng g−1) in centrifuged EVOO samples were up to 1000 times lower than in non-centrifuged oils. We have shown that pomace residue, even when present in very small quantity (1 g of pomace in 1 kg of oil), significantly altered concentrations and relative proportions of many elements in EVOO. Therefore, adequate sample pre-treatment (removal of pomace residue via centrifugation) is essential for determining real multi-element composition of olive oil. This is critical in application of EVOO multi-element composition in traceability studies and determination of geographic origin of olive oil.

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.

An important part of agriculture in the European Mediterranean area is olive (Olea europaea L.) production. Characterising the relationships between properties of different soils where olive is grown and nutrient status in olive leaves can enhance our understanding of soil-plant interactions. Three different soils (Terra rossa, Rendzina, Lithosol) were characterized for their physical and chemical characteristics ; plant- available nutrients were extracted with ammonium nitrate. Soils, soil extracts and leaf digests were analysed for nutrients and for nitrogen in soils and leaf. A redundancy analysis (RDA) was applied to elucidate relationships between soil properties and leaf nutrients. As revealed by RDA, leaf concentrations of Mg, K, Ca and micronutrients were explained by available Mg, total carbonates and soil organic carbon in topsoil. Leaf concentration of Na was associated with total Na in topsoil. Copper and Mo deficiencies were detected in plants grown in Lithosol, and Mg, P, Mn and Zn deficiencies were noted in all plants. Through appropriate agronomic techniques, Lithosols can be used for olive groves, but they have significant limitation regarding nutrient availability. Our results support the relevance of using soil nutrient variability to provide a basis for optimisation of measures for olive groves.

The influence of agronomical factors (two growing areas and four harvest periods) and storage conditions of virgin olive oils (room temperature, +4 and −20 °C) on tocopherols was investigated on two cultivars having significantly different tocopherol content (Oblica 269–443 mg/kg, Leccino 403–784 mg/kg). α-Tocopherol accounted for 97 % of total tocopherols and its content decreased during ripening of both cultivars. In a warmer growing area both cultivars gained a higher γ-tocopherol content while only Leccino showed a higher content of α-tocopherol. After 12 months of storage α-tocopherol content decreased by up to 27 %. Lower storage temperatures did not always contribute to the higher stability of α-tocopherol compared to room temperature.

The objective was to evaluate physical and chemical properties of eight pomegranate accessions (seven cultivars and one wild genotype) collected from the Mediterranean region of Croatia. Accessions showed high variability in fruit weight and size, calyx and peel properties, number of arils per fruit, total aril weight, and aril and juice yield. Variables that define sweet taste, such as low total acidity (TA ; 0.37% - 0.59%), high total soluble solids content (TSS ; 12.5% - 15.0%) and their ratio (TSS/TA) were evaluated, and results generally aligned with sweetness classifications of the fruit. Pomegranate fruit had a high variability in total phenolic content (1985.6 to 2948.7 mg/L). HPLC-MALDI-TOF/MS analysis showed that accessions with dark red arils had the highest total anthocyanin content, with cyanidin 3-glucoside as the most abundant compound. Principal component analysis revealed great differences in fruit physical characteristics and chemical composition among pomegranate accessions.

The present study aimed to examine the effect of foliar (Mn_fol) and soil Zeolite-Mn (Mn_ZA) application on leaf mineral, total phenolic and oleuropein content, and mycorrhizae colonization of self-rooted cv. Leccino plantlets grown on calcareous soil. RESULTS The dissolution of zeolite was 97% when citric acid was applied at 0.05?mM?dm?3, suggesting that organic acids excreted by roots can dissolve modified zeolite (Mn_ZA), making Mn available for plant uptake. The leaf Mn concentration was the highest for Mn_fol treatment at 90 days after transplanting (DAT) (172?mg?kg?1) and 150 DAT (70?mg?kg?1) compared to other treatments. Mn_ZA soil application increased leaf Mn concentration at 150 DAT compared to control and NPK treatments. The oleuropein leaf content was highest for Mn_fol compared to other treatments at 90 DAT and lowest at 150 DAT. Arbuscular mycorrhizal colonization was higher for Mn_fol treatment at 150 DAT compared to all other treatments. CONCLUSION Changes in the arbuscular colonization percentage and oleuropein content may be connected to stress conditions provoked by a high leaf Mn concentration in the Mn_fol treatment at 90 DAT. Mn_ZA application increased leaf Mn concentration at 150 DAT compared to control and NPK treatments. It can be assumed that the dominant mechanism in Mn uptake from modified zeolite is Mn_ZA dissolution through root exudates. ? 2018 Society of Chemical Industry

Olive oil represents an important ingredient in the Mediterranean diet and is appreciated for both nutritional and sensory properties, often related to geographical area where the olives are grown and the olive cultivar. As consumers demand correct labeling of olive oil, there is a need for analytical techniques that are able to provide data and confirm traceability of origin and authenticity of the oil. Stable isotope ratios have long been known to have enormous potential for food source screening and have been used in authenticity studies for many food products. Results of stable isotope ratios analyzed by EA-IRMS technique are not influenced by cultivar or the agricultural techniques in the groves, and is a valuable tool for geographical discrimination of unknown samples. The carbon isotope ratio (13C/12C) of olive oils was determined by EA-IRMS (Elemental Analyzer – Isotope Ratio Mass Spectrometry). All analyses were performed in triplicates. Analysis of variance was performed on the obtained dana using SAS Institute v9.4 software.

Fruit samples of ‘Granada’, ‘Wonderful’ and ‘Hicaznar’ cultivars were collected in productive pomegranate orchard in Neretva valley, Metković (Croatia) and their pomological and chemical properties were compared. Significant differences among cultivars were noted between the studied traits. Fruit weight ranged from 429.37 g to 359.43 g and the lowest was recorded in cv. ‘Hicaznar’. Color of peel, aril and juice of all investigated cultivars was intensively red and dark red, respectively. ‘Granada’ and ‘Wonderful’ stood out with high juice yield compared with ‘Hicaznar’. Total soluble solid (TSS) of ‘Hicaznar’ (18.61%) was higher than that of ‘Wonderful’ (16.64%). Total acidity (TA) significantly differed among cultivars and ranged from 1.6% to 2.1%. According to the TSS/TA ratio investigated cultivars belong to the group of sour-sweet cultivars. Dissimilarity between cultivars was found in the phenolics content (TPC). It ranged from 679.6 to 906.6 mg/100 g D.W. where ‘Hicaznar’ stood out as a cultivar with highest TPC and also highest flavonoid and non-flavonoid content (521.1 mg/100 g D.W. and 385.5 mg/100 g D.W., respectively). In ‘Granada’ antioxidant activity measured by 1,1-diphenyl-2-picrylhydrazyl was recorded for 64.1%, in ‘Wonderful’ 70.2% and the highest in ‘Hicaznar’ (74.5%). Results of this assessment are the basis for practical determination of the pomegranate use., Uzorci plodova sorata ‘Granada’, ‘Wonderful’ i ‘Hicaznar’ prikupljeni su u proizvodnom nasadu šipka u dolini rijeke Neretve, Metković (Hrvatska) te su uspoređene njihove pomološke i kemijske karakteristike. Između istraživanih sorata utvrđene su značajne razlike. Masa ploda varirala je od 429,37 g do 359,43 g, a najmanja masa ploda utvrđena je kod sorte ‘Hicaznar’. Boja kore i arilusa (zrna) te soka svih istraživanih sorata je crvena odnosno tamno crvena. Plodovi sorte 'Granada' i 'Wonderful' istaknuli su se višim randmanom soka u usporedbi sa sortom 'Hicaznar'. Sadržaj topljive suhe tvari (TSS) sorte ‘Hicaznar’ (18,61%) je veći u odnosu na TSS sorte ‘Wonderful’ (16,64%). Ukupna kiselost (TA) se značajno razlikovala između sorata i varirala je od 1,6% do 2,1%. Temeljem TSS/TA odnosa istraživane sorte pripadaju skupini kiselo-slatkih sorata. Različitost između sorata utvrđena je u sadržaju fenolnih spojeva (TPC) koji su bili u rasponu od 679,6 do 906,6 mg/100 g s.tv. Sorta ‘Hicaznar’ se istakla najvećim sadržajem ukupnih fenola, kao i sadržajem flavonoida i ne-flavonoida (521,1 mg/100 g s.tv. i 385,5 mg/100 g s.tv.). Antioksidacijska aktivnost mjerena sa 1,1-diphenyl-2-picrylhydrazyl sorte ‘Granada’ iznosila je 64,1%, ‘Wonderful’ 70,2%, a najveća je bila kod sorte ‘Hicaznar’ (74.5%). Rezultati ovog istraživanja osnova su za definiranje mogućnosti uporabe šipka.

International audience; Reduction of nitrogen application in crop production is desirable for ecological and health-related reasons. Interestingly, nitrogen deficiency can lead to enhanced concentrations of polyphenols in plants. The reason for this is still under discussion. The plants' response to low nitrogen concentration can interact with other factors, for example radiation intensity. We cultivated red and green leaf lettuce hydroponically in a Mediterranean greenhouse, supplying three different levels of nitrogen (12 mM, 3 mM, 0.75 mM), either in full or reduced (-50%) radiation intensity. In both red and green lettuce, we found clear effects of the nitrogen treatments on growth characteristics, phenolic and photosynthetic compounds, nitrogen, nitrate and carbon concentration of the plants. Interestingly, the concentrations of all main flavonoid glycosides, caffeic acid derivatives, and sucrose increased with decreasing nitrogen concentration, whereas those of chlorophylls, beta-carotene, neoxanthin, lactucaxanthin, all trans-and cis-violaxanthin decreased. The constitutive concentrations of polyphenols were lower in the green cultivar, but their relative increase was more pronounced than in the red cultivar. The constitutive concentrations of chlorophylls, a-carotene, neoxanthin, all trans-and cis-violaxanthin were similar in red and green lettuce and with decreasing nitrogen concentration they declined to a similar extent in both cultivars. We only detected little influence of the radiation treatments, e.g. on anthocyanin concentration, and hardly any interaction between radiation and nitrogen concentration. Our results imply a greater physiological plasticity of green compared to the red lettuce regarding its phenolic compounds. They support the photoprotection theory regarding anthocyanins as well as theory that the deamination activity of phenylalanine ammonia-lyase drives phenylpropanoid synthesis.

One of the most important antioxidants in virgin olive oil (VOO) are phenolic compounds. The amount of phenolic substances present in VOO, as well as the fatty acid composition, is related to the health beneficial effects that make VOO a very valuable and appreciated commodity. The level of these substances is a very important parameter in the evaluation of VOO quality since phenols are strictly related both to the oil’s resistance to oxidation because of their antioxidative properties. The aim of the present study was to define parameters for the characterization, polyphenolic composition and related antioxidative properties of monovarietal olive oil from cv. Drobnica grown in Dalmatia (Croatia). We also examined the antioxidant activity, total antioxidant capacity and oxidative stability of Drobnica’s oil. Besides several qualitative parameters (free acidity, peroxide value and UV spectrophotometric indices), the analyses of major (fatty acids) and minor components (phenolic fraction and their antioxidant power evaluated by ABTS●+ and electrochemical test) were also carried out. Radical scavenging activity of phenolic extracts was performed by ABTS+ and DPPH methods. An amperometric flow injection method (FIA) was used for the evaluation of the antioxidant power (AOP) of the phenolic extracts of the oil samples. The evaluation of correlation coefficients between parameters DPPH, ABTS, AOP and certain fatty acids and phenolic groups were performed. Olive oil from Drobnica showed high proportion of oleic and palmitic acid. Stable 18:1/18:2 ratio leads to conclusion that this oil has pretty high oxidative stability. Moderate positive correlation between DPPH and linoleic acid was detected, as well as moderate positive correlation between DPPH and the ratio of oleic and linoleic acids. The positive correlation was detected between DPPH and secoiridoides derivates.

Pomegranate (Punica granatum L.) in Croatia is grown on its southern coastal area. Main production is concentrated in the area of the river Neretva. In this study pomological and chemical characterization of nine cultivars of pomegranate grown in Metkovic (Bokežan, Barski slatki, Ciparski rani, Crveni rani, Dividiš, Kristal, Konjski zub, Sladun and Šerbetaš) was done. The following characteristics of the fruit were determined: fruit weight, length, width and shape, color of the skin, arils and juice, aril weight, aril and juice yield, dry matter content, total titratable acids (citric acid eq.) and pH value. The results showed significant differences between cultivars in all analysed parameters.

Fenolni spojevi su prirodni antioksidansi prisutni u djevičanskom maslinovom ulju (DMU) koji utječu na konačnu procjenu kvalitete pojedinog maslinovog ulja. To su bioaktivni spojevi koji imaju izraženu antioksidacijsku aktivnost i značajno utječu na oksidacijsku stabilnost DMU, ali i na njegova senzorska svojstva. U ovom radu ispitivan je sastav fenola u djevičanskim maslinovim uljima iz odabranih autohtonih hrvatskih sorta s nekoliko lokacija na području srednje Dalmacije. Trogodišnja istraživanja provedena su na sortnim uljima dobivenim istovjetnim tehnološkim postupkom prerade. Provedeno je i senzorsko ocjenjivanje sortnih DMU kojima su definirana specifična obilježja okusa i arome koja se pripisuju isključivo sorti. U preliminarnim istraživanjima određeni su osnovni parametri kvalitete prema propisima za ekstra djevičansko maslinovo ulje, kao i ukupni udjel fenolnih tvari te sastav pojedinačnih fenola za pojedino sortno ulje. Kod nekih sorti su pojedine grupe fenolnih spojeva (sekoiridoidi, flavoni, lignani) pokazale veću antioksidacijsku aktivnost nego ukupni fenoli. Kod ulja drugih sorti, oksidacijska stabilnost ovisi upravo o udjelu ukupnih fenola. Kod svih ispitivanih uzoraka u ovom istraživanju vrlo je dobar udjel fenola i različitih sastava pojedinačnih fenolnih spojeva, ovisno o sorti. Senzorske karakteristike razlikuju se kod uzoraka ulja ovisno o ishodnoj sorti i imaju određena svojstva za svako pojedino sortno ulje., Phenolic compounds are natural antioxidants present in virgin olive oil (VOO) that influence the final assessment of the quality of certain olive oil. These are the bioactive compounds that have a pronounced antioxidant activity and significantly affect the oxidative stability of the VOO, but also its sensorial properties. This paper examined the composition of phenolic compounds in VOO's from selected indigenous Croatian varieties from several locations in central Dalmatia. A three-year study was conducted on varietal oils obtained by identical chemical processing procedure. Sensory evaluation of monovarietal VOO’s was also conducted and specific characteristics of taste and aroma due to the olive variety were defined. In preliminary research, the basic quality parameters were determined according to the regulations for the extra virgin olive oil, as well as the total phenol content and the composition of individual phenolic compounds for particular monovarietal oils. Some varieties showed that a particular group of phenols (secoiridoided, flavones, lignans) had higher antioxidant activity than total phenols. In oils from other olive varieties, oxidative stability depended on the proportion of total phenols. In all samples in this study very good total phenol content was detected as well as different composition of individual phenolic compounds, depending on the olive cultivar. Sensorial characteristics of the samples varied depending on the variety and had specific attributes for each monovarietal VOO.

The evaluation of the influence of olive oil phenols on the stability of extra virgin olive oils by the determination of the oxidative stability index, the ABTS and DPPH radical test, and the quali-quantitative analysis of the phenolic compounds, plays a key role in the assessment of the overall olive oil quality. In this study virgin olive oils from selected autochthonous Croatian varieties were investigated in order to evaluate the contribution of their phenolic compounds on the oxidative stability. Two year researches were conducted on the monovarietal olive oils (Oblica, Lastovka, Levantinka, Drobnica, Mastrinka) obtained by the same technological processing system, centrifugal extraction into two phases. The olive fruits came from different groves in Dalmatia region, a central part of Croatian Adriatic coast. The polar extracts of olive oil samples were submitted to spectrophotometric analysis of total phenols and to liquid chromatographic determination of their quali-quantitative profile (HPLC-DAD/MSD). To obtain a complete description of oil samples, fatty acid composition, ultraviolet indices (K232, K270, and ΔK), free acidity degree and peroxide value were also determined according to the European Union methods 20 stated in Regulation 2568/91. Beside analyses mentioned above, researches are amplified by oxidative stability determination by Rancimat method, evaluation of antioxidant activity by DPPH and ABTS methods as well as antioxidant capacity (AOP). The evolution of the analytical parameters studied shows that certain groups of phenolic compounds (secoiridoides, flavones and lignans) have a higher antioxidant activity and antioxidant capacity than the total phenols. The results obtained in this study will contribute to better understanding of peculiar characteristics of local varieties of olive oil and set the basis for their characterization and evaluation.