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Research background. Baranjski kulen is one of the most popular fermented meat sausages originating from Croatia. It has protected geographical indication, and is traditionally produced in the Baranja region of Croatia. Kulenova seka is a fermented sausage very similar to baranjski kulen, but it has a different calibre and consequently, a shorter time of production. In recent decades, due to the high demand and popularity of these products, industrially produced baranjski kulen and kulenova seka have become available on the market. This work aims to identify specific characteristics of traditional and industrial sausages baranjski kulen and kulenova seka on proteome, peptidome and metabolome level, which could potentially lead to better optimization of the industrial production process in order to obtain an equivalent to the traditional product. Experimental approach. Protein profiles of baranjski kulen and kulenova seka (traditional and industrial) were analysed using two-dimensional gel electrophoresis followed by differential display analysis and protein identification by mass spectrometry. Peptidomic profile was analysed via liquid chromatography-tandem mass spectrometry. Furthermore, aroma profiles were investigated via headspace solid phase microextraction and gas chromatography-mass spectrometry. Results and conclusions. The major identified characteristics of each product were: industrial baranjski kulen: specific degradation of myosin-1 and titin, overabundance of stress-related proteins and increased phenylalanine degradation; traditional baranjski kulen: decreased concentration of phenylalanine and overabundance of fructose-bisphosphate aldolase A and carbonic anhydrase 3; industrial kulenova seka - specific myosin-4 and haemoglobin subunit alpha degradation process; traditional kulenova seka - overabundance of dihydropyrimidine dehydrogenase [NADP(+)] and myosin light chain 1/3, skeletal muscle isoform, degradation of albumin and myoglobin, decreased concentrations of almost all free amino acids and increased amounts of smoke-derived volatile compounds. Presented results showed that potential product type-specific quality markers for each sausage could be found. Novelty and scientific contribution. In this preliminary communication, the first insights into protein degradation processes and generation of peptides, free amino acids and aroma compounds of industrial and traditional baranjski kulen and kulenova seka are presented. Although further research is needed to draw general conclusions, the specific profile of proteins, peptides, amino acids and volatile compounds represents the first step in the industrial production of sausages that meet the characteristics of traditional flavour.

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.

To differentiate monovarietal wines made from native and introduced varieties in Istria (Croatia), samples of Malvazija istarska, Chardonnay and Muscat yellow from two harvest years (2013 and 2014) were subjected to headspace solid-phase microextraction and gas chromatographic/mass spectrometric analysis (HS-SPME-GC/MS) of volatile aroma compounds. Significant effects of variety and harvest year were determined, but their interaction complicated the differentiation. Particular compounds were consistent as markers of variety in both years: nerol for Malvazija, ethyl cinnamate and a tentatively identified isomer of dimethylbenzaldehyde for Chardonnay, and terpenes for Muscat yellow. Wines from 2013 contained higher concentrations of the majority of important volatiles. A 100 % correct differentiation of Malvazija istarska and Chardonnay wines according to both variety and harvest year was achieved by stepwise linear discriminant analysis.

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.

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.

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.

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.

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.