Search

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.

Olive leaves as by-products of olive farming are rich natural source of bioactive compounds with antioxidant properties. In this study, the efficiency of the natural maceration of fresh and steam blanched olive leaves in refined rapeseed oil was investigated, as well as the effect of degree of leaf fragmentation (whole, cut, ground) and maceration time on transfer of bioactive compounds (polyphenols) and pigments (chlorophylls) in oil. In oils obtained by maceration, changes of total phenolic compounds and total chlorophylls were determined spectrophotometrically. The effect of these oil preparation procedures on oil quality indicators was also investigated through free fatty acid content and spectrophotometric indices. The content of total phenols and chlorophylls increased in oils obtained by maceration of fresh and steam blanched olive leaves, and were in statistically significant correlation with leaf fragmentation degree. The highest content of total phenols was achieved in oils with whole fresh leaves (220.4 mg/kg) after seven days of maceration while the chlorophylls transfer to oils was the most efficient when ground steam blanched leaves were macerated for 28 days (79.10 mg/kg). Maceration of olive leaves slightly deteriorated the quality of refined rapeseed oil, equally in oils with fresh and steam blanched olive leaves. This simple preparation procedure can be efficiently used for enrichment of refined oils with natural antioxidants.

Leaves and infusions of six Croatian olive cultivars grown in an organic orchard under the same agronomic conditions were characterised by high- performance liquid chromatography- ultraviolet/visible spectrophotometry (HPLC- UV/VIS). The total identified phenols in leaves ranged from 3 818 mg 100 g–1 [cultivar Istarska crnica (IC)] to 10 572 mg 100 g–1 of dry mass [cultivar Oblica (OB)]. The canonical discriminant analysis (CDA) provided a distinct separation of cultivars based on leaves' phenolic profiles. Hot- and cold-water infusions (200 mL) were prepared from 1 g of dry leaves. The average transfer rate of the total phenols in the cold-water infusions was 40% (25 °C/30 min), while in the hot-water infusions was 63% (75 °C/3 min) and 76% (100 °C/3 min). Although the cold-water infusions had the lowest transfer rate, they contained important levels of hydroxytyrosol derivatives ranging from 16.6 mg 200 mL–1 to 36.5 mg 200 mL–1 depending on the cultivar. Therefore, both hot and cold preparations are effective in obtaining antioxidant-rich natural beverages

In order to investigate the potential of various olive cultivars and leaf sampling times for phytochemical farming practice in Croatia, phenolic and mineral composition was determined in olive leaves of four Croatian cultivars and Italian cultivar Leccino collected at three occasions, in October 2017, January 2018, and March 2018. Istarska bjelica turned out to have the largest phytochemical potential among the investigated cultivars due to steady high oleuropein concentrations found in its leaves. The concentration of main phenolic components in Istarska bjelica leaves changed only slightly during the sampling period, suggesting the possibility of its higher capability for low air temperatures stress resistance and different metabolic response compared to the other studied cultivars. Low air temperatures increased the oleuropein level and antioxidant activity in leaves of Leccino, Oblica, Levantinka, and Drobnica cultivars, which may be of crucial phytochemical farming interest. Each of the investigated olive cultivars was characterized by a specific leaf mineral nutrient composition, which could have had a specific role in their interplay with phenols.

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.

U ovom radu istražena je učinkovitost hladne i tople (Soxhlet) ekstrakcije ulja iz suhe tvari liofiliziranih maslinovih tijesta (bez koštice i s košticom) te iz sjemenki ploda masline sorte Leccino. Istražen je i utjecaj ekstrakcije na sadržaj ukupnih fenolnih tvari i orto-difenola u dobivenim uljima. U maslinovim tijestima i sjemenkama određen je udio ukupnih fenola i antioksidacijski kapacitet (IC50). Hladna i topla ekstrakcija pokazale su se podjednako učinkovite u izdvajanju ulja iz liofiliziranih maslinovih tijesta, dok je topla ekstrakcija bila učinkovitija u izdvajanju ulja iz sjemenki. Maslinova tijesta bez koštice imala su najveći udio fenolnih tvari (12,9 mg g-1 s.t.) od tri ispitivana biljna materijala. Stoga su i ulja dobivena iz njih, osobito ona dobivena toplom ekstrakcijom, sadržavala najveće udjele ukupnih fenola (396,7 mg kg-1) i orto-difenola (206,3 mg kg-1). U odnosu na maslinova tijesta, sjemenke su imale statistički značajno niži udio ukupnih fenola te višestruko niži antioksidacijski kapacitet. Rezultati su potvrdili da se uklanjanjem koštice smanjuje negativni utjecaj peroksidaza iz sjemenki na fenolne tvari u tijestu i ulju, te upućuju da se primjenom tople ekstrakcije povećava topljivost fenolnih tvari iz biljnog materijala u ulju., In this work, the effectiveness of cold and hot (Soxhlet) extraction of oil from the dry matter of lyophilized olive pastes (without pit and with pit) and seeds of olive fruits of Leccino cultivar, was investigated. The effect of extraction on the content of total phenols and ortho-diphenols in the obtained oils was also investigated. Total phenols content and antioxidant capacity (IC50) were determined in olive pastes and seeds. Cold and hot extraction proved to be equally effective in extracting oil from lyophilized olive pastes, while hot extraction was more efficient in extracting oil from seeds. Olive pastes without pits had the highest total phenols content (12.9 mg g-1 of dry mass) of the three investigated plant materials. Therefore, the oils obtained from them, particularly those obtained by Soxhlet extraction, contained the highest total phenols content (396.7 mg kg-1) and ortho-diphenols (206.3 mg kg-1). Compared to olive pastes, the seeds had a statistically significantly lower total phenols content and a multiple lower antioxidant capacity. The results confirmed that pits removal reduces the negative influence of peroxidases from seeds on the phenol compounds in the olive paste and in the oil, also suggesting that hot extraction increases the solubility of phenols from plant material in the oil.

The present study investigated the effect of boron (B) foliar application on the dynamic changes in the concentration of phenols, especially oleuropein, and volatile compounds of olive leaves during a 90-day period. The trial was conducted in a greenhouse on one year old olive plantlets, sprayed with B at 41.62 mM against a water treated control. It was revealed that total phenols and oleuropein concentration in old and in young olive leaves increased in B treated leaves 90 days after application. Furthermore, B enhanced the concentration of particular terpene and norisoprenoid volatiles in olive leaf infusion. The obtained results may give a new perspective in biochemical farming practice, with a possibility to increase the amounts of phenols and terpenes in olive leaves intended for medical uses, and to enhance olive plant resistance to pathogens and insects.

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.

Six monocultivar virgin olive oils (VOOs) produced from five autochthonous (Buza, Buza Puntoza, Istarska Bjelica, Porecka Rosulja, and Rosinjola) and one referent cultivar (Leccino), were investigated. The mass fractions of orthodiphenols (ORT) and tocopherols (TOC) were analysed by VIS spectroscopy and HPLC. The radical-scavenging capacity was evaluated by electron spin resonance spectroscopy (ESR) using galvinoxyl free radical and the DPPH test. Results revealed a high level of total TOC in VOOs of Buza Puntoza (243 mg kg(-1)) and Porecka Rosulja (325 mg kg-1). VOOs contained in 100 g from 79% (Istarska Bjelica) to 261% (Porecka Rosulja) of recommended daily allowance of a-tocopherol. The mass fraction of ORT in Istarska Bjelica and Rosinjola was > 250 mg kg-1 (on average 30-40% higher in comparison to other studied cultivars). Istarska Bjelica and Porecka Rosulja showed the highest antioxidant capacity in both methods of measurement. The highest capacity to inhibit protein carbonylation (PC) in response to oxidative stress (54-56%) was displayed by Buza Puntoza, Leccino, and Buza. High level of positive linear correlation between ORT mass fraction and radical-scavenging capacity measured by DPPH test (r=0.768), as well as strong negative correlation between PC inhibition and mass fraction of ORT (r=-0.697), were observed.

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 influence of the phenolic content in olive paste of cv. Buža increased by the addition of an aqueous solution of phenolic extract of freeze-dried olive pulp (cv. Istarska bjelica) on the final products of the lipoxygenase pathway in oil was studied. Increases by 12, 38, and 56% for ripe fruits (maturity index = 4.0) and by 38% for unripe fruits (maturity index = 1.2) were examined. Phenols in the olive paste were determined according to the HPLC method, whereas volatiles in oil were determined according to SPME-GC-MS. A significant negative effect on Z-3-hexenal and E-2-hexen-1-ol (Tukey’s test, p < 0.05) was found for ripe fruits (average decreases of 55 and 60%, respectively), but not for the unripe sample. Positive effects in both ripening levels were found for Z-3-hexenyl acetate (average increase of 68% for ripe and a double increase for unripe fruits) and total C5 compounds (average increase of 32% for ripe and an increase of 30% for unripe fruits).

The effect of processing aids (2.5 % of talc, NaCl or KCl) on oil extractability and the profile of phenolic and volatile compounds of Istarska bjelica and Leccino oils was studied. Talc significantly increased extractability in both cultivars, while salts increased extractability in Leccino cv. In the laboratory extracted oils, phenols were determined by a RP-HPLC–DAD method, whereas volatiles were determined by SPME/GC–MS. Talc addition significantly decreased hydroxytyrosol and increased ligstroside derivatives in produced oils, but did not affect the total phenol content. Among volatile compounds, only Z-2-penten-1-ol in Leccino and 1-pentene-3-one in Istarska bjelica oils significantly increased by talc addition. Salts improved transfer of most individual phenols into oil, particularly oleuropein derivatives, and increased C6 aldehydes and C5 volatiles in Leccino oils. NaCl exerted a stronger effect in increasing individual phenols and volatiles than KCl.

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.

Godišnja proizvodnja mandarina u dolini Neretve tj. u glavnom uzgojnom području Hrvatske, iznosi u prosjeku oko 40.000 tona, a u najboljim godinama može doseći i do 50.000 tona. Ukupna hrvatska proizvodnja mandarina pokriva potrebe domaće potrošnje, dio se izvozi na europsko tržište, ali se u prosjeku javlja i oko 12.000 tona viška. Do pojave viškova dolazi zbog zastoja u berbi ili zbog otkupa i prodaje koji nisu prilagođeni tržišnim uvjetima. Budući da se u tom slučaju ne radi o planiranoj namjenskoj proizvodnji mandarina za preradu, količina sirovina od godine do godine može znatno varirati. Takvim okolnostima prilagodljivi su pogoni za preradu voća manjih kapaciteta, smješteni u neposrednoj blizini proizvodnog područja, koji mogu poslovati u okviru obiteljskih gospodarstava ili zadruga, te proizvoditi različite prerađevine od plodova mandarina. Za proizvođače mandarina to može otvoriti nove mogućnosti samozapošljavanja i biti dodatni izvor prihoda., Annual production of mandarins (tangerine) in the Neretva valley (the main breeding area of Croatia), reach an average of about 40,000 tons, and in the some years can reach up to 50,000 tons. The total production of mandarins covers the needs of Croatian market; part is exported to the European market, but on average occurs about 12,000 tons of surpluses. The surplus is due to delays in the harvest or the purchase and sale which are not adapted to market conditions. Since in this case is not about the planned purpose production of mandarins for processing, the amount of raw materials from year to year may vary significantly. Such circumstances are adaptable for fruit smaller processing units, located near the production areas, which can operate in the context of family farms and cooperatives, and produce a variety of products from the fruits of mandarin. For mandarin growers it can open up new opportunities for self-employment and be an additional source of income.

The aim of this investigation was to determine the impact of fruit ripening on chemical and sensorial changes in monovarietal olive oils obtained from two important olive cultivars grown in Croatia, Buža and Crna. In Buža oils peroxide value, K232 and K270 increased during ripening, while no differences among three ripening stages in Crna oils were observed. Oils of both cultivars at the later ripening stages had higher free acidity level and lower sensory score followed by mild loss in almost all positive sensory characteristics. Total phenols and antioxidant capacity decreased in Buža oils during fruit ripening, while in Crna oils reached maximum level in purple stage and then progressively decreased in the black ripening stage. Oleic acid level slightly increased during ripening in both cultivar oils. Linoleic acid decreased in Buža oils obtained from black fruits while palmitic acid decreased in Crna oils during ripening. In both monovarietal oils chlorophyll and carotenoids concentrations decreased during ripening. The two cultivars had different course of total aldehydes, total esters and total ketones during ripening, while total alcohols were the highest in oils from purple ripening stage and then decreased as ripening progress. Practical applications: During the ripening, the chemical composition of olive fruit changes influencing the quality grade, oxidative stability, sensory characteristics and nutritional value of the obtained products. The cultivars characterized by a similar trend of ripening process could have different course of chemical and sensorial changes in oil during fruit ripening. Therefore, knowledge about these changes is important for determination of proper harvest time of single cultivar to achieve optimum of its potential regarding desirable characteristics of obtained oil.

The influence of filtration through a hydrophilic cotton layer on volatile compounds, sensory characteristics and colour of two monovarietal oils was investigated in this study. Volatiles were evaluated using headspace solid-phase microextraction-gas chromatography. After the filtration of Buža oils only a slight increase in total alcohols was noticed. In filtered Črna oils a significant decrease of total alcohols and slight changes in total aldehydes, total ketones and total C5 volatile compounds concentration were detected. No significant influence on the sensory scores of oils, but some slight changes in sensorial profiles were noted (slightly higher intensities of sensory characteristics apple and grass, and higher values of the lightness L(∗) in filtered samples). The results point to unequal filtration impact on different monovarietal oils and could be useful in developing targeted technologies for specific monovarietal oils quality improvement.

Phenolic and volatile compounds are closely related to valuable gastronomic and nutritional properties, as well as oxidative stability of virgin olive oil. Since biochemical synthesis and transformation of these compounds during olive processing depend on the activity of endogenous enzymes, which are partially influenced by genetic factors, mixtures of different cultivars could have either a synergistic or antagonistic effect on phenolic and volatile compounds in the resulting oil. In this context, two specific cultivars from the Istrian peninsula, Leccino (L) and Istarska bjelica (B), were selected. Two monovarietal fruit samples (L100 and B100) and four mixtures in the following mass ratios: L/B=80:20, L/B=60:40, L/B=40:60 and L/B=20:80 were prepared. The mass fraction of total phenols was determined colourimetrically, while C6 and C5 volatiles from lipoxygenase pathway were determined by headspace solid-phase microextraction-gas chromatography. Mass fraction of total phenols in the oil samples from fruit mixtures changed linearly from (199.5±7.2) in Leccino to (642.0±61.7) mg/kg in Istarska bjelica, in a strict correlation with fruit mass ratio of the two cultivars. Leccino monovarietal samples had statistically higher values (p≤0.05) of C6 aldehydes ((15.32±1.69) vs. (10.91±0.62) mg/kg) and C6 alcohols ((2.96±0.98) vs. (0.17±0.05) mg/kg), but lower values of C5 compounds ((0.77±0.12) vs. (0.96±0.05) mg/kg) compared to Istarska bjelica samples. Volatiles having a direct contribution to the oil aroma (odour activity value >1.0) were 1-penten-3-one (84–201), E-2-hexenal (26–42), hexanal (1.8–2.4) and Z-2-penten-1-ol (1.3–2.6). A significant synergistic effect was observed for C6 aldehydes in the case of L/B=40:60 fruit mixture. The addition of Istarska bjelica to Leccino fruits caused a significant antagonistic effect on C6 alcohols, but no significant deviations from the expected values were found in the case of C6 esters and C5 compounds. Results suggest that fruit combinations of two chosen cultivars in olive processing offer interesting possibilities for targeted modulation of phenolic and volatile compounds in virgin olive oil, and consequently, their sensory and nutritional characteristics., Fenolni i hlapljivi spojevi te oksidacijska stabilnost djevičanskog maslinovog ulja utječu na njegova gastronomska i hranjiva svojstva. Budući da biokemijska sinteza i transformacija fenolnih i hlapljivih spojeva tijekom prerade maslina ovisi o aktivnosti endogenih enzima, koja je dijelom određena genetskim faktorima, mješavine plodova različitih sorti mogu imati bilo sinergistički, bilo antagonistički učinak na njihov udjel u dobivenim uljima. Odabrane su dvije specifične sorte Istarskog poluotoka, Leccino (L) i Istarska bjelica (B). Dva sortna uzorka plodova (L100 i B100) te četiri mješavine plodova (masenih omjera: L/B=80:20, L/B=60:40, L/B=40:60 i L/B=20:80) prerađeni su u laboratorijskom uređaju. Maseni udjel ukupnih fenola određen je kolorimetrijski dok su C6 i C5 hlapljive tvari iz lipoksigenaznog puta određene mikroekstrakcijom na čvrstoj fazi iz para iznad ulja i plinskom kromatografijom. Maseni se udjel ukupnih fenola u uzorcima ulja dobivenim od mješavina plodova mijenjao linearno od (199,5±7,2) u ulju sorte Leccino do (642,0±61,7) mg/kg sorte Istarska bjelica, ovisno o promjeni masenih udjela plodova tih sorata. Ulje sorte Leccino imalo je statistički značajno više (p≤0,05) C6 aldehida ((15,32±1,69) mg/kg) i alkohola ((2,96±0,98) mg/kg), ali manje C5 spojeva ((0,77±0,12) mg/kg) u usporedbi s uljem sorte Istarska bjelica, koje je imalo ove vrijednosti: (10,91±0,62) mg/kg C6 aldehida, (0,17±0,05) mg/kg C6 alkohola i (0,96±0,05) mg/kg C5 spojeva. Hlapljivi spojevi koji utječu na aromu ulja (mirisna aktivnost >1,0) bile su 1-penten-3-on (84-201), E-2-heksenal (26-42), heksanal (1,8-2,4) i Z-2-penten-1-ol (1,3-2,6). Miješanjem plodova u omjeru L/B=40:60 postignut je sinergistički učinak na udjel C6 aldehida. Dodatak Istarske bjelice plodovima sorte Leccino utjecao je antagonistički na udjel C6 alkohola, ali ne i na udjele C6 estera i C5 spojeva. Rezultati upućuju na zaključak da se miješanjem plodova dviju odabranih sorti u preradi mogu dobiti ulja s ciljanim udjelom fenolnih i hlapljivih sastojaka ulja, te željenih senzorskih i hranjivih svojstava.

In order to evaluate the role of intrinsic characteristics of olive cultivars on dynamics of oil quality parameters changes related to the olive fruit fly (Bactrocera oleae (Gmelin)) attack, two specific olive cultivars were compared, Istarska bjelica and Buža. I. bjelica is characterised by late ripening, a lower flesh/stone mass ratio and higher oleic/linoleic ratio, the total phenols content and oil mass fraction compared to Buža. Oil samples were obtained at two harvesting dates, from fruit lots with 0, 25, 50, 75 and 100% of infestation degree, expressed by mass. Oil and water content in olive paste, as well as total phenols, fatty acids composition and standard chemical and sensorial oil quality parameters were determined. At equal maturity level, the cultivar with a higher oil (24 ± 1% vs. 16 ± 1%) and lower water content (54 ± 2% vs. 61 ± 4%) was more susceptible to hydrolytic degradation, while the one with the lower total phenols content (231 ± 32 vs. 575 ± 124 mg/kg) and oleic/linoleic fatty acid ratio (5.7 vs. 9.1) was more liable to oxidative deterioration of oil. Lower susceptibility to negative flavours formation could be related to the absence of ripening induced by fly attack and less favourable environment for larvae growth (higher total phenols content, lower water content and flesh/stone mass ratio). Practical applications: Understanding the impact of olive fly attack is the basis of scientific and practical interest in the production of olives and olive oil. Different intrinsic characteristics of olive cultivars could lead to different susceptibility to oil quality deterioration caused by olive fly attack, which opens a possibility to adjust and minimise pesticide treatments. Knowledge about this topic could contribute to the reduction of costs of olive pests control, as well as to the improvement of quality and food safety concept in olive oil production.

Three methods, most frequently used in hydrophilic phenols extraction from virgin olive oils (liquid–liquid, solid-phase with C18 and solid phase with diol-bound sorbents), were applied on virgin olive oils enriched with 2.0–10.0 mg/kg of phospholipids (granular de-oiled soy lecithin). Phospholipids addition significantly decreased the total phenols concentration determined colorimetrically. Liquid–liquid extraction showed the best repeatability and recovery, and the lowest decrease of total phenols extracted in the presence of phospholipids. Extraction rate declined with the increase of phospholipids concentration, but showed a kind of saturation behaviour. Addition of phospholipids (5 g/kg) to various commercial extra virgin olive oils resulted in a different degree of total phenols decrease (from 1% to 45%), probably because of different affinity of phospholipids toward different classes of phenolic compounds. During prolonged contact time between phenols and phospholipids (60-days storage), oxidation monitored by K270 and a decrease of total phenols concentration proceeded more rapidly in the presence of phospholipids.

In order to study the influence of some polar compounds, naturally present in virgin olive oils, on the volatiles release, the volatiles-free olive oil matrix was enriched with free fatty acids (FFA) (concentration range from 0.35 to 1.40 g/100 g), sterols (1.0 - 2.5 g/kg) and phospholipids (1.6 - 6.0 g/kg). Sixteen standards of virgin olive oil aroma compounds were dissolved in thus obtained olive oil matrices. Volatiles compounds were analyzed by headspace solid phase microextraction with DVB/CAR/PDMS fiber and gas chromatography with flame ionization detection. Evaluation of the data by statistical analysis revealed that FFA, sterols and phospholipids, in concentration ranges considered in this study, generally did not significantly influence the determination of virgin olive oil volatiles. The most important changes occurred in the release of the three alcohols (Z-2-penten-1-ol, 1-hexanol and E-3-hexen-1-ol) and 3-methylbutyl acetate which slightly decreased upon the increase of FFA concentration.

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.

Cilj istraživanja bio je odrediti udio kuhinjske soli (NaCl) u tradicionalnim mesnim proizvodima iz skupine trajnih kobasica, trajnih i polutrajnih suhomesnatih proizvoda te slanina, podrijetlom s obiteljskih poljoprivrednih gospodarstava iz tri hrvatska proizvodna područja: Istre i Dalmacije, Središnje te Istočne Hrvatske. Maseni udio soli određen je u 124 uzorka tradicionalnih mesnih proizvoda te su utvrđene vrijednosti po vrstama proizvoda i proizvodnim područjima korelirane s prosječnom dnevnom konzumacijom mesnih proizvoda u Hrvatskoj te preporučenim dnevnim unosom soli. Rezultati analize pokazali su najveći udio soli u suhomesnatim proizvodima (6,16±0,68%), zatim u slanini (5,30±0,71%) te najmanji u trajnim kobasicama (4,20±0,60%). Statistički značajna razlika u udjelu soli nije utvrđena (p > 0,05) između domaće kobasice i kulena. U skupini trajnih i polutrajnih suhomesnatih proizvoda utvrđen je statistički značajno veći (p < 0,05) udio soli u suhoj šunki i pršutu u odnosu na suhu vratinu, lopaticu i svinjsku pečenicu te dimljenu vratinu. U kategoriji slanina, između slanine, špeka i pancete, nije utvrđena statistički značajna razlika (p > 0,05). Udjeli soli u istim vrstama mesnih proizvoda u ovisnosti o proizvodnom području Hrvatske, nisu se statistički značajno razlikovali što je rezultat sličnosti u recepturama i tehnologijama proizvodnje. Rezultati istraživanja potvrđuju da tradicionalni mesni proizvodi predstavljaju značajan izvor soli te da stoga, u cilju očuvanja ljudskog zdravlja, trebaju biti umjereno zastupljeni u ljudskoj prehrani., The aim of this study was to determine the proportion of table salt (NaCl) in traditional meat products from the group of dry sausages, dry and semi-dry meat products and bacons, originating from family farms from three Croatian production areas: Istria and Dalmatia, Central Croatia and Eastern Croatia. Mass fraction of salt was determined in 124 samples of traditional meat products and established values by type of product and by production area were correlated with average daily consumption of meat products in Croatia and the recommended daily salt intake. The analysis results showed the highest salt content in dry cured meat products (6.16 ± 0.68%), then in bacons (5.30 ± 0.71%) and lowest in dry sausages (4.20 ± 0.60%). A statistically significant difference in the proportion of salt has not been established (p > 0.05) between the homemade sausages and Kulen. In the group of dry and semi-dry cured meat products, there was a statistically significantly higher (p < 0.05) salt proportion in the dry ham and prosciutto in comparison to dry rack, dry shoulder, pork serloin and smoked rack In the category of bacons, bettwen a bacon, „špek“ and pancetta statistically significant differences (p > 0.05) were not determined. Proportions of salt in the same types of meat products in dependence of the Croatia production area, were not significantly different, as a result of the similarities in recipes and production technologies. The research results confirm that traditional meat products are an important source of salt and therefore, in order to protect public health, it should be moderately represented in the human diet., Ziel dieser Arbeit war es, den Anteil an Kochsalz (NaCl) in traditionellen Fleischprodukten aus der Gruppe der Dauerwürste, haltbaren und teilweise haltbaren Rohwurstprodukte sowie diversen Specksorten zu bestimmten, die aus landwirtschaftlichen Familienbetrieben aus drei kroatischen Regionen stammen: Istrien und Dalmatien, Zentral- und Ostkroatien. Der Massenanteil von Salz wurde in 124 Proben traditioneller Fleischprodukte bestimmt; danach wurden die gewonnenen Werte nach Produkten und Produktionsregionen mit dem täglichen Verzehr von Fleischprodukten und der empfohlenen Tageszufuhr von Salz in Korrelation gebracht. Die Ergebnisse der Auswertung zeigten den größten Salzanteil in Rohwurstprodukten (6,16±0,68%), gefolgt von Speck (5,30±0,71%) und den niedrigsten Anteil in Dauerwürsten (4,20±0,60%). Zwischen der hausgemachten Wurst und dem Kulen wurde im Anteil von Salz keine statistisch relevante Diƒerenz festge- stellt (p > 0,05). In der Gruppe der haltbaren und teilweise haltbaren Rohwurstprodukte wurde ein statistisch erheblich größerer Anteil von Salz (p < 0,05) im luftgetrockneten Schinken und im Prosciutto im Vergleich zum luftgetrockneten Schweinekamm, zum Schulterblatt und Schweinerücken sowie zum geräucherten Schweinekamm festgestellt. In der Speckkategorie konnte zwischen dem luftgetrockneten und dem geräuchertem Speck keine statistisch relevante Diƒerenz (p > 0,05) festgestellt werden. Die Salzanteile in diversen Fleischprodukten weisen, in Abhängigkeit vom Produktionsgebiet in Kroatien, keine statistisch relevanten Diƒerenzen auf, was auf die Ähnlichkeit der Rezepturen und der Produktionstechnologien zurückzuführen ist. Die Untersuchungsergebnisse bestätigen, dass die traditionellen Fleischprodukte eine bedeutende Salzquelle darstellen und daher zum Erhalt der Gesundheit in der menschlichen Ernährung maßvoll vertreten sein sollten., Obiettivo di questa ricerca era quello di stabilire la frazione massica di sale da cucina (NaCl) contenuta nei salumi tradizionali appartenenti alle categorie delle salsicce e dei salami stagionati, dei prodotti di carne essiccati a media e lunga conservazione e della pancetta (speck, bacon) originari delle aziende agroalimentari a conduzione familiare di tre aree produttive della Croazia: Istria e Dalmazia, Croazia centrale e orientale. È stata determinata la frazione massica del sale in 124 campioni di salumi tradizionali, sono stati accertati i valori per tipologia di prodotto e di area di produzione correlati al consumo medio giornaliero di prodotti di carne in Croazia e alla dose giornaliera consigliata di sale. I risultati dell’analisi hanno accertato una maggiore percentuale di sale nei prodotti di carne essiccati (6,16±0,68%), seguiti dalla pancetta (speck, bacon) (5,30±0,71%) e, per nire, dalle salsicce e dai salami stagionati (4,20±0,60%). Non è stata evidenziata alcuna di#erenza statisticamente signicativa (p > 0,05) nella percentuale di sale tra le salsicce e i salami caserecci e i “kulen”. Nella categoria dei prodotti di carne essiccati a media e lunga conservazione, è stata evidenziata una percentuale maggiore statisticamente signicativa (p < 0,05) di sale nel prosciutto cotto essiccato e nel prosciutto crudo (“pršut”) rispetto al capocollo, alla spalla e alla lonza di maiale essiccati e al capocollo a#umicato. Nella categoria dalla pancetta (speck, bacon), tra il bacon, lo speck e la pancetta non è stata riscontrata alcuna di#erenza statisticamente signicativa (p > 0,05). Le percentuali di sale nelle medesime tipologie di salume, in dipendenza dell’area produttiva della Croazia, non hanno fatto riscontrare di#erenze statisticamente signicative, il che è dovuto alla similitudine delle ricette e delle tecnologie di produzione utilizzate nelle diverse aree produttive. I risultati della ricerca confermano che i salumi tradizionali appresentano una signicativa fonte di sale e che, pertanto, ai ni della tutela della salute umana, vanno consumati con moderazione., El n de esta investigación fue determinar la proporción de la sal común (NaCl) en productoscárnicos tradicionales del grupo de salchichas, productos cárnicos crudo-curados y semi-curados y jamones de granjas familiares de tres zonas de producción en Croacia: Istria y Dalmacia, Croacia central y el este de Croacia. El porcentaje de masa de la sal fue determinado para 124 muestras de los productos cárnicos tradicionales y fueron determinadas las valores según los tipos de productos y las zonas de producción en relación con el consumo diario promedio de los productos cárnicos en Croacia, y con el comsumo diario recomendado de la sal. Los resultados del análisis mostraron la proporción más alta de la sal en productos cárnicos crudo-curados (6,16±0,68%), en jamón (5,30±0,71%) y el menor en las salchichas crudo-curadas (4,20±0,60%). La diferencia estadísticamente signicante en la proporción de la sal (p > 0,05) no fue determinada entre las salchichas caseras y el kulen. En el grupo de los productos cárnicos crudo-curados y semi-curados fue determinada la proporción de la sal estadísticamente más grande (p < 0,05) en jamón seco y el jamón con respecto a la media paletilla seca, al hombro, la carne rostizada y la paleta ahumada. En la categoría de los jamones, entre el jamón, el tocino y la panceta, la diferencia estadísticamente signicante no fue determinada (p > 0,05). Las proporciones de la sal en los mismos tipos de productos cárnicos, dependiendo de las zonas de producción en Croacia, no se dirieron estadísticamente, debido a las semejanza en las recetas y tecnologías de producción. Los resultados de la investigación conrman que los productos cárnicos tradicionales son una fuente signicante de la sal y por lo tanto hay que consumarles moderadamente, con el n de mantener la salud humana.

The influence of low storage temperature (+4 °C and －20 °C) and conventional storage room temperature on the quality parameters, phenolic contents and volatile profiles of Buža, Črna and Rosinjola monovarietal virgin olive oils after 12 months of storage was investigated in this study. Virgin olive oils stored at low temperatures maintained better quality parameters than oils stored at room temperature. A negligible decrease in the total phenols was detected after 12 months of storage at all investigated temperatures. The total volatile compounds, aldehydes, alcohols and esters in almost all stored samples were unchanged compared to fresh oils. Total ketones increased after storage, although at a lower temperature these changes were less notable. An increase in the oxidation indicators hexanal and hexanal/E-2-hexenal ratio was the lowest in oils stored at +4 °C.Storage at temperatures lower than room temperature could help to prolong the shelf-life of extra virgin olive oil by maintaining high quality parameters and preserving the fresh oil’s volatile profile.Se ha estudiado la influencia, durante 12 meses, de temperaturas bajas (+4 °C y −20 °C) y convencional (ambiente), sobre los parámetros de calidad, contenido fenólico y perfil de volátiles de aceites de oliva vírgenes monovarietales Buža, Črna y Rosinjola. Los aceites de oliva vírgenes almacenados a bajas temperaturas mantienen mejores propiedades de calidad que los aceites almacenados a temperatura ambiente. Se encontró una disminución no significativa de los fenoles totales después de 12 meses de almacenamiento a todas las temperaturas estudiadas. Los compuestos volátiles totales, aldehídos, alcoholes y ésteres, en casi todas las muestras almacenadas, se mantuvieron sin cambios en comparación con los aceites frescos. Las cetonas totales incrementaron tras el almacenamiento, aunque a temperaturasmas bajas estos cambios fueron menos notables. El incremento de los indicadores de la oxidación hexanal y la relación hexanal/E-2-hexenal fue más bajo en los aceites almacenados a +4 °C. El almacenamiento a temperaturas inferiores a la temperatura ambiente ayuda a prolongar la vida útil de los aceites de oliva virgen extra, manteniendo la alta calidad y preservando el perfil de volátilesde un aceite fresco.

This paper describes a method suitable for the analysis of diglycerides (DG) in cheese. The method, also suitable for other foods, is essentially based upon the solid-phase extraction (SPE) of DG followed by capillary gas chromatographic analysis with a polar stationary phase (TAP). SPE is applied to avoid the column overloading caused by triglycerides; however, SPE is able to catalyse isomerization from the 1,2-form to the 1,3-form. This introduces an error into the results, as the two forms have different origins and are produced at different stages of ripening. A comparison between the use of silica and diol phases was made and it was seen that no isomerization occurred when the diol phase was used. Repeatability and recovery trials were carried out and the coefficient of variation (relative standard error) of the former trial was approximately 10%. Finally, it is demonstrated that it is possible to re-use the SPE cartridge at least four times.

The volatile compounds found in virgin olive oil, mainly C6 and C5 volatile compounds biogenerated from polyunsaturated fatty acids through the lipoxygenase pathway, are responsible for their particular aroma. The composition of volatile compounds in olive oil depends on the cultivar, the ripening degree of the fruits and processing conditions. Among many different autochthonous cultivars in Istria (Croatia), some of the most prevalent are Buža, Črna and Rosinjola. The volatiles and sensory characteristics of their monovarietal virgin olive oil are little known. Therefore, fruits from these three cultivars were handpicked at the same ripening degree and processed under the same conditions. Quantitative descriptive sensory analysis of monovarietal virgin olive oil was carried out by the panel. Volatile composition was evaluated by headspace solid phase microextraction-gas chromatography, previously optimized and validated. The main parameters affecting effectiveness, time and temperature of extraction were optimized. The extraction procedure showed detection and quantification limits, as well as linear ranges adequate for the analysis of selected volatile compounds. Good precision was obtained both in terms of intra-day repeatability (relative standard deviations generally lower than 7 %) and inter-day precision. The tested types of monovarietal olive oil showed different volatile profiles, although E-2-hexenal was the main compound in all samples. Buža oil was the richest in total C6 and C5 volatile compounds. The results show that the most important contributors to the olive oil aroma (odour activity value >1.0) were 1-penten-3-one, E-2-hexenal, hexanal, hexanol, Z-3-hexen-1-ol and Z-2-penten-1-ol. These chemical findings were compared with those provided by the panel test. Buža had the highest intensity of sensory characteristic 'other ripe fruits' and Rosinjola had the highest intensity of sensory characteristic 'bitter'. All results show that olive oil aroma compounds accumulate differently depending on the cultivar, indicating a close dependence on the enzymatic pool, which is genetically dependent., Specifičnu aromu djevičanskih maslinovih ulja određuju hlapljive tvari, a osobito C6 i C5 hlapljive tvari koje nastaju na lipoksigenaznom putu iz višenezasićenih masnih kiselina. Sastav hlapljivih tvari ovisi o sorti, stupnju zrelosti plodova i uvjetima prerade. Iako su Buža, Črna i Rosinjola jedne od najbrojnijih među različitim istarskim sortama, nedovoljno su poznate njihove hlapljive tvari i senzorska svojstva ulja. Plodovi tih sorti istog stupnja zrelosti brani su ručno i prerađeni pod istim uvjetima, a kvantitativnu deskriptivnu senzorsku analizu proizvedenih djevičanskih maslinovih ulja proveo je panel ocjenjivača. Prethodno optimiranom i validiranom metodom mikroekstrakcije na čvrstoj fazi iz para iznad ulja i plinskom kromatografijom određen je sastav hlapljivih tvari. Optimirani su vrijeme i temperatura, čimbenici koji najviše utječu na učinkovitost ekstrakcije. Metoda mikroekstrakcije prikladna je za analizu odabranih hlapljivih tvari, što je ustanovljeno granicama detekcije i kvantifikacije te linearnim odzivom detektora. Preciznost metode potvrđena je dnevnim mjerenjima (kada je relativna standardna devijacija bila većinom manja od 7 %) te onima u razmaku od tri dana. Analizirana sortna maslinova ulja imala su različit sastav hlapljivih tvari, iako je E-2-heksenala bilo najviše u svim uzorcima. Ulje Buže imalo je najviše ukupnih C6 i C5 hlapljivih tvari. Rezultati su pokazali da aromi maslinovih ulja najviše pridonose (vrijednost mirisne aktivnosti>1,0) 1-penten-3-on, E-2-heksenal, heksanal, heksanol, Z-3-heksen-1-ol i Z-2-penten-1-ol. Rezultati kemijskih analiza uspoređeni su s rezultatima panel testa. Najjači intenzitet senzorskog svojstva 'ostalo zrelo voće' imala je sorta Buža, a sorta Rosinjola najjači intenzitet senzorskog svojstva 'gorko'. Može se zaključiti da se hlapljive tvari arome maslinovih ulja akumuliraju različito u različitim sortama, tj. da ovise o genetski određenom enzimskom potencijalu.

Istarska županija sudjeluje u količinama i kapacitetima maslinarske i uljarske djelatnosti Hrvatske s nešto više od 15%, a u pogledu kvalitete ulja vodeća je hrvatska regija. Polazna pretpostavka bila je da su karakteristike djelatnosti prerade maslina u ovoj regiji bitni čimbenici za postizanje visoke kvalitete djevičanskog maslinovog ulja. Aktualne karakteristike istražene su za razdoblje od 2007. do 2009. godine metodom intervjuiranja u 25 pogona, neovisno o njihovoj veličini ili obliku registracije. Utvrđeno je da su snage djelatnosti u promatranom razdoblju bile: mogućnost brze prerade cjelokupnog godišnjeg uroda zbog povoljnog omjera ukupnog kapaciteta prerade (24,4 t/h) i mase uroda (prosječno 6.250 t); mogućnost brze prerade ploda nakon berbe zbog dobre raspoređenosti pogona na uzgojnom području (najveća udaljenost do najbližeg pogona prosječno 15 km) te usklađenosti veličine kapaciteta pojedinačnih pogona (raspon 50 kg/h - 3.500 kg/h; prosječan kapacitet 974 kg/h; median 700 kg/h) s potrebama korisnika; visoka zastupljenost centrifugalnih sustava s 2 izlaza (58,1% ukupnog kapaciteta); visoka zastupljenost spremnika za ulje od preporučenih materijala (84,5% ukupnog kapaciteta). Slabosti koje je moguće ublažiti dobrom organizacijom rada bile su: nedovoljno prostora za skladištenje maslina do prerade u kontroliranim uvjetima (34,7% ukupnog kapaciteta) te niska zastupljenost ambalaže preporučenih karakteristika za skladištenje maslina do prerade (19,5% ukupnog kapaciteta). Slabosti za čije su rješavanje potrebna dodatna ulaganja bile su: nedovoljno prostora za skladištenje ulja za prodaju u kontroliranim uvjetima (41,7% ukupnog kapaciteta); nedovoljna primjena inertne atmosfere u skladištenju ulja za prodaju (38,8% ukupnog kapaciteta); nedovoljna obrada i neprikladno uklanjanje biljne vode (54% od ukupne količine)., Istria participates in Croatian olive-growing and olive oil processing with amounts and capacities of 15%, and is the leading Croatian region regarding oil quality. The assumption is that olive oil processing activities in this region are substantial factors for achieving virgin olive oil of high quality. Actual characteristics were examined for the period 2007 – 2009 by the method of interviews in 25 processing plants, regardless of their size or type of registration. It was found that the driving forces of this activity in the observed period were: possibility of fast processing of the total annual olive yield, because of the favorable ratio between total processing capacity (24.4 t/h) and yield mass (on average 6250 t); possibility of fast fruit processing after harvesting, because of good plants location in the olive-growing area (maximum distance to the nearest plant is on average 15 km) and coordination of single plant capacity size (range 50 kg/h - 3500 kg/h; average 974 kg/h; median 700 kg/h) with the clients requirements; high participation of two-phase centrifugation systems (58.1% of total capacity) and a good supply of oil containers made from recommended materials (84.5% of total capacity). The weaknesses which can be moderated by good organization of work were: lack of stockrooms with controlled storage conditions for olives fruits (34.7% of total capacity), and low supply of olive storage containers having recommended characteristics (19.5% of total capacity). The weaknesses which can be resolved by additional investments were: lack of stockrooms with controlled storage conditions for oil intended for sale (41.7% of total capacity); insufficient application of inert atmosphere in storage of oil intended for sale (38.8% of total capacity); insufficient processing and inappropriate removal of vegetable water (54% of total capacity).

Bitter hydrophilic phenolic compounds contained in virgin olive oil (VOO) beneficially affect human health. However, consumers mostly do not tolerate oils with a pronounced bitter taste (bitterness index K225 ≥ 0.360) and this could limit their consumption. The possibility of bitterness attenuation of quite bitter VOO (K225 = 0.501) by the addition of granular soy lecithin, as a source of phospholipids, up to the levels present in seed oils (2.5–30 g/kg), was evaluated by sensory difference tests. Statistically significant differences were found starting from 5 g/kg of added phospholipids (p ≤ 0.05). Phospholipids addition caused a significant decrease of the total concentration of 20 volatiles determined by HS-SPME–GC analysis (slope 0.056; r = −0.9962), and the most influenced among them was E-2-hexenal (slope 0.048; r = −0.9975). Results of quantitative descriptive sensory analysis showed that the addition of phospholipids in a range from 5 to 10 g/kg slightly reduced olive fruity and green odor notes, significantly increased sweetness and decreased bitterness. The significant changes of overall sensory quality grading were not found between pure VOO and samples enriched with phospholipids. Thus, in the context of functional food formulation, addition of phospholipids could be proposed as a procedure useful for bitterness attenuation of VOO.

Virgin olive oil (VOO) enriched with phospholipids (soy lecithin) up to the levels present in seed oils (from 2.5 to 10.0 g/kg) was studied as a potential functional food. Lecithin addition slightly increased the concentration of tocopherols and considerably increased K270 values. In the fatty acid composition, an increase of linoleic and a slight decrease of oleic acid were observed, as the decrease of monounsaturated/polyunsaturated fatty acid ratio. The radical scavenging activity was evaluated by two methods: electron spin resonance spectroscopy using galvinoxyl free radical and VIS-spectroscopy measurement of the disappearance of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. Results indicate that lecithin addition retards the scavenging activity of VOO that is ascribed to the bipolar character of lecithin and its ability to entrap hydrophilic antioxidants. The effect of lecithin addition to the oxidative stability of VOO was evaluated by the Rancimat method, and a positive linear correlation (r = 0.9849) with induction time was determined.

An on-line LC-GC method was used to assess the n-alkane composition of forty olive oil samples obtained from three different cultivars from restricted grove zone in Croatia. Olive samples were handpicked at three different ripening stages during four consecutive years. No significant differences were found in relation to the variable “ period of harvesting” , while the effects “ variety” and “ year” as well as their interaction caused significant differences for most of the n-alkane components (p ≤ 0.05). Despite the influence of the production year, linear discriminant analysis based on the n-alkane components was able to correctly identify the variety of 97.5% of the samples.