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To investigate the phenolic and aroma composition of Malvazija istarska (Vitis vinifera L.) white wines produced by an unconventional technology comprising prolonged maceration followed by maturation in wooden barrels, representative samples were subjected to analysis by UV/Vis spectrometry, high-performance liquid chromatography, and gas chromatography-mass spectrometry. When compared to standard wines, the investigated samples contained higher levels of dry extract, volatile acidity, lactic acid, phenols, colour intensity, antioxidant activity, majority of monoterpenes, C13-norisoprenoids, methanol, higher alcohols, ethyl acetate, branched-chain esters and esters of hydroxy and dicarboxylic acids, ethylphenols, furans, and acetals, as well as lower levels of malic acid, β-damascenone, straight-chain fatty acids, ethyl and acetate esters. It was estimated that maceration had a stronger influence on phenols, and maturation on volatile aromas. Despite different vintages and technological details, the investigated wines showed a relative homogeneity in the composition, representing a clear and distinctive type., Pomoću UV/Vis spektrometrije, visokodjelotvorne tekućinske kromatografije, te kombinacijom plinske kromatografije i spektrometrije masa ispitan je fenolni i aromatski sastav reprezentativnih uzoraka bijelih vina sorte malvazija istarska (Vitis vinifera L.) proizvedenih nekonvencionalnom tehnologijom, koja obuhvaća produljenu maceraciju i dozrijevanje u drvenim bačvama. U usporedbi sa standardnim vinima, ispitani su uzorci imali veću koncentraciju suhog ekstrakta, mliječne kiseline, fenola, većine monoterpena, C13-norizoprenoida, metanola, viših alkohola, etil-acetata, estera razgranatog lanca i estera hidroksi i dikarboksilnih kiselina, etil-fenola, furana i acetala, zatim intenzivniju boju, veću antioksidacijsku aktivnost i hlapljivu kiselost, a manju koncentraciju jabučne kiseline, β-damascenona, masnih kiselina ravnog lanca, etilnih i acetatnih estera. Ocijenjeno je da je maceracija znatno utjecala na fenolni sastav, a dozrijevanje na sastav hlapljivih spojeva arome. Unatoč različitim godištima berbe i tehnološkim detaljima, ispitana su vina imala relativno homogeni sastav, te su predstavljala jasan i prepoznatljiv tip.

Svrha je ovog interdisciplinarnog istraživanja bila pridonijeti karakterizaciji sorata maslina i maslinovog ulja u Istri (Hrvatska), prikazujući po prvi put morfološki i genetički profil sorte Bova, te kemijske i senzorske karakteristike njezinog ulja. Morfološke su karakteristike sorte Bova određene u skladu s metodologijom Međunarodnog vijeća za masline, a molekularna je karakterizacija izvršena pomoću jedanaest mikrosatelitnih markera. Sorta Bova morfološki je i genetički drukčija od ostalih dosad opisanih istarskih sorata maslina. Mikrosatelitni profil sorte Bova bio je jedinstven i u usporedbi s više od 200 različitih talijanskih genotipova dobivenih korištenjem istog seta biljega. Kako bi se okarakteriziralo ulje sorte Bova, prikupljeni su plodovi s tri stabla maslina istog stupnja zrelosti, te odvojeno prerađeni u jednakim uvjetima. Sastav hlapljivih tvari u dobivenim uzorcima ulja utvrđen je mikroekstrakcijom na čvrstoj fazi i plinskom kromatografijom/masenom spektrometrijom. Određeno je oko 50 hlapljivih spojeva, uglavnom ugljikovodika (34,69 % ukupne površine pikova), zatim aldehida (25,80 %), alkohola (22,24 %), ketona (8,76 %), organskih kiselina (4,08 %), terpena (2,10 %), estera (2,18 %) i furana (0,26 %). Ulje sorte Bova bilo je bogato ukupnim C6 (39,87 %) i C5 hlapljivim tvarima (13,85 %), nastalim u lipooksigenaznom putu. Najzastupljeniji hlapljivi spoj bio je C6 aldehid E-2-heksenal. Panel za senzorsku analizu proveo je kvantitativnu deskriptivnu senzorsku analizu ispitivanih uzoraka maslinovog ulja. Senzorski profil ulja okarakteriziran je srednjim intenzitetom arome ploda masline, zelenog lišća i trave, zatim blagim mirisom po rajčici i aromatičnom bilju, te naposljetku laganim notama jabuke i drugog zrelog voća. Okus je okarakteriziran gorčinom srednjeg do jakog intenziteta, popraćenom umjerenom pikantnosti te blagom slatkoćom., This interdisciplinary study aims to contribute to the characterization of Istrian (Croatia) olive cultivars and oil, giving for the first time the morphological and genetic profile of Bova cultivar, and chemical and sensorial characteristics of its oil. Morphological features of Bova cv. were determined according to the International Olive Council methodology, while molecular characterization was performed using eleven microsatellite markers. Bova cultivar was morphologically and genetically different from other described Istrian olive cultivars. The microsatellite profile of Bova was also unique when compared to more than 200 different Italian genotypes using the same set of markers. In order to characterize the oil from Bova cv., fruits from three trees at the same ripening stage were harvested and processed separately under the same conditions. Volatile composition of the obtained oil samples was determined using solid-phase microextraction with gas chromatography/mass spectrometry. About 50 volatiles were detected, mostly hydrocarbons (34.69 % of total peak area), followed by aldehydes (25.80 %), alcohols (22.24 %), ketones (8.76 %), organic acids (4.08 %), terpenes (2.10 %), esters (2.18 %) and furans (0.26 %). Bova oil was rich in total C6 (39.87 %) and C5 volatiles (13.85 %), biogenerated through the lipoxygenase pathway. The most prevalent volatile compound was C6 aldehyde E-2-hexenal. Quantitative descriptive sensory analysis of the investigated olive oil samples was carried out by a sensory panel. The sensory profile was characterized by medium intensities of olive fruity, green leaves and grass, light tomato and aromatic herbs flavours with mild apple and other ripe fruit notes. The taste was characterized by medium to strong bitterness, followed by medium pungency and mild sweetness.

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.

The influence of different grape mash maceration treatments on the varietal and secondary aroma profiles of wines produced from an aromatic red grape variety, Muškat ruža porečki, have been investigated. Two essentially different techniques were applied, fermentative maceration at room temperature and prefermentative cryomaceration, both in durations of one, three and five days. Generally, higher concentrations of free and bound varietal aroma compounds were found in wines obtained by maceration at room temperature in relation to cryomaceration. Regarding the effect of the duration of maceration, the highest concentrations were determined in wines obtained by three-day maceration treatments, in both fermentative and cryomaceration treatments. Secondary aroma compounds followed a less uniform pattern. The compounds with the highest odour unit values in all investigated wines were linalool, citronellol, geraniol, β-damascenone, β-ionone, isoamyl alcohol, 2-phenylethanol, ethyl hexanoate, ethyl octanoate, isoamyl acetate, ethyl acetate, and diethyl succinate. It has been shown that Muškat ruža porečki is an aromatic variety, producing wines with notable monoterpenol fraction, which are characterized by a typical varietal Muscat aroma with a dominant rose odour accompanied by red fruit nuances. Sensorially, longer maceration treatments improved odour and overall wine quality, together with the intensity and recognisability of varietal Muscat aroma, while short-term cryomaceration emerged as a preferable technique for the production of light rosé wines with pronounced Muscat aroma and low phenolic content. The presented maceration techniques were shown to be applicable for the production of different types of Muškat ruža porečki rosé and red wines., U radu je istražen utjecaj različitih postupaka maceracije masulja na sortni i sekundarni aromatski profil vina proizvedenih od aromatične crne sorte grožđa Muškat ruža porečki. Primjenjene su dvije različite tehnike, i to fermentativna maceracija na sobnoj temperaturi i prefermentativna kriomaceracija, obje tijekom jednog, tri i pet dana. U vinima su dobivenim maceracijom masulja pri sobnoj temperaturi, u usporedbi s vinima proizvedenim kriomaceracijom, pronađene veće koncentracije slobodnih i vezanih spojeva koji pridonose sortnoj aromi. Što se tiče utjecaja trajanja maceracije, najveće su koncentracije tih spojeva utvrđene u vinima dobivenim nakon trodnevne maceracije, bilo fermentativne, bilo kriomaceracije. Sekundarni aromatski spojevi slijedili su manje jedinstven obrazac. Spojevi s najvećim vrijednostima mirisne aktivnosti u svim ispitanim vinima bili su: linalol, zatim citronelol, geraniol, β-damascenon, β-ionon, izoamilni alkohol, 2-feniletanol, etil heksanoat, etil oktanoat, izoamil acetat, etil acetat, i dietil sukcinat. Dokazano je da je Muškat ruža porečki aromatična sorta grožđa, od koje se dobivaju vina sa zamjetnom monoterpenskom frakcijom, karakterizirana tipičnom sortnom muškatnom aromom s dominantnim mirisom ruža, praćenim nijansama crvenog voća. Dulje trajanje maceracije pridonijelo je mirisu i ukupnoj kakvoći vina, naglašavajući intenzitet i prepoznatljivost sortne muškatne arome, dok se kratkotrajna kriomaceracija pokazala kao poželjna tehnika za proizvodnju laganih rosé vina s izraženom muškatnom aromom i niskim sadržajem fenola. Predstavljene tehnike maceracije mogu se primijeniti za proizvodnju različitih tipova rosé i crnog vina sorte Muškat ruža porečki.

In order to investigate the composition of secondary aroma compounds of fresh grape marc distillates as a result of variety and production technology, 30 samples (6 varieties×5 samples) were analysed. White grape marc samples from Malvazija istarska, Chardonnay and Muscat Blanc were obtained as by-products in standard white wine production, while red grape marc samples from Teran and Cabernet Sauvignon were obtained after standard red wine production procedures. Marc from red grape variety Muškat ruža porečki was obtained during the production of rosé wines. All fermented marc samples were distilled using a traditional copper alembic. The obtained distillates were subjected to GC/MS and GC/FID analyses. Malvazija istarska distillates exhibited exceptionally high methanol content. Distillates from white grape varieties were found to be characterized by higher C6 alcohol and 1-propanol concentrations, while red grape distillates contained higher amounts of the majority of alcohols, acids, and esters. In Muškat ruža distillates intermediate concentrations of many important aroma compounds were found. It was concluded that differences in the production technology parameters, depending on the variety, resulted in differences in secondary aroma profiles, most evident between distillates from white and red varieties. These findings were confirmed applying stepwise linear discriminant analysis (SLDA), which resulted in 100 % correct classification of distillates according to the variety and corresponding production technology., Da bi se ispitao sastav spojeva sekundarne arome u svježim rakijama komovicama uzrokovane sortom i odgovarajućom tehnologijom proizvodnje, analizirano je 30 uzoraka (6 sorti×5 uzoraka). Uzorci komine bijelih sorata grožđa Malvazija istarska, Chardonnay i Muscat Blanc dobiveni su kao nusproizvod u standardnoj proizvodnji bijeloga vina, dok su uzorci komine sorata crnoga grožđa Teran i Cabernet Sauvignon dobiveni standardnim postupkom proizvodnje crnoga vina. Uzorci komine sorte crnoga grožđa Muškat ruža porečki dobiveni su pri proizvodnji rosé vina. Svi uzorci prevrele komine destilirani su u tradicionalnom bakrenom kotlu za destilaciju. Dobivene rakije komovice podvrgnute su GC/MS i GC/FID analizi. Komovice od sorte Malvazija istarska imale su iznimno veliki udjel metanola, a od sorata bijeloga grožđa veće koncentracije C6 alkohola i 1-propanola, dok su komovice od crnih sorata sadržavale veću količinu većine alkohola, kiselina i estera. U komovicama od Muškat ruže porečke pronađene su srednje koncentracije mnogih važnih spojeva arome. Zaključeno je da su različiti uvjeti proizvodnje, koji ovise o sorti, uzrokovali različitu sekundarnu aromu, najizraženiju u komovicama od sorata bijeloga i crnoga grožđa. Te su spoznaje provjerene primjenom postupne linearne diskriminantne analize koja je omogućila 100 % točnu klasifikaciju rakija komovica na osnovi sorte i odgovarajuće tehnologije proizvodnje.

During a two-year study, the effect of different grape mash maceration treatments (skin contact at 20 °C for 10, 20 and 30 h) and cryomaceration (skin contact at 7 °C for 10, 20 and 30 h) on the concentration of free and bound monoterpenes and total phenols in Malvazija istarska wine (the most spread white wine variety in Istria) was monitored. Monoterpenic alcohols linalool, a-terpineol, citronellol, nerol and geraniol were determined by gas chromatography after isolation on octadecylsilica (C18) sorbent and elution with pentane/dichlorometane ratio of 2:1, while total phenols were determined spectrophotometrically with Folin-Ciocalteau reagent. Sensory evaluation of wines was performed using the Buxbaum method. The obtained results show that linalool and geraniol are the most abundant monoterpenes in Malvazija istarska, and that grape mash maceration treatments cause significant increase of free and bound monoterpene concentrations compared to those in control treatment wine obtained without maceration. The content of phenols, which are subject to oxidation, was found to be significantly lower in wines produced by cryomaceration treatments, while in those produced by maceration at 20 °C the concentration of total phenols increased proportionally with the duration of maceration, negatively influencing wine quality by causing higher colour intensity and bitter taste., Tijekom dvogodišnjeg istraživanja praćen je utjecaj različitih postupaka klasične maceracije masulja pri 20 °C (10, 20 i 30 sati) i hladne maceracije pri 7 °C (10, 20 i 30 sati) na koncentraciju slobodnih i vezanih monoterpena, te ukupnih fenola u vinima istarske Malvazije. Monoterpenski alkoholi linalol, α-terpineol, citronelol, nerol i geraniol određeni su metodom plinske kromatografije prethodnom ekstrakcijom na sorbensu oktadecilsilicijevom dioksidu (C18) uporabom otapala pentan:diklormetan (2:1), a ukupni fenoli spektrofotometrijski s Folin–Ciocalteu reagensom. Analizirana su vina senzorski ocijenjena Buxbaum metodom. Iz dobivenih se rezultata vidi da je najviše linalola i geraniola u vinu istarske Malvazije (najraširenije bijele vinske sorte u Istri), a postupcima maceracije masulja značajno se povećava koncentracija slobodnih i vezanih monoterpena u usporedbi s kontrolnim uzorkom vina dobivenog bez maceracije. Koncentracija oksidaciji podložnih fenola kudikamo je manja u vinima proizvedenim hladnom maceracijom, dok u postupcima maceracije na 20 °C proporcionalno raste koncentracija ukupnih fenola koji negativno utječu na kakvoću vina, uzrokujući jači intezitet boje i gorčinu okusa.