a b s t r a c tPhenolic composition of twenty-two Macedonian red wines, including ten autochthonous monovarietal Vranec wines produced with different yeasts for fermentation, and twelve wines from international varieties (Syrah, Merlot and Cabernet Sauvignon) from different wine regions was studied. All wines presented relatively high value of total phenols and antioxidant activity. A total of 19 phenolic compounds were identified and quantified using HPLC-DAD and among them, malvidin-3-glucoside and its derivatives were the major compounds, followed by the petunidin derivatives, while caftaric acid was the predominant cinnamic acid derivative in all wines. The anthocyanin content was mainly affected by the grape variety and to a less extent by the yeast used in fermentation. In particular, the use of locally isolated yeasts affected higher amount of anthocyanins and phenolic acids compared to the wines fermented with commercial yeasts. Principal Component Analysis showed a satisfactory grouping of red wines according to the grape variety.

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In this study, electrothermal atomic absorption spectrometry (ETAAS) was used for determination of lead and cadmium in Macedonian white wines. Wine samples, without prior purification, were directly injected into the ETAAS system, using matrix modifiers for Pb and Cd. The standard addition method was used for quantitative analysis of Pb and Cd content. Reliability of the method was verified by determination of selected validation characteristics. The results of the measurements indicated satisfactory precision and accuracy, confirming that the method is accurate and convenient for quantitative analysis. The lead and cadmium concentrations were ranged between 2-28.5 and 0.4-5.69 μg/L, respectively. The levels were below the maximal allowed concentration in wine and compare well with those reported for similar wines from other parts of the world.

An analytical method for determination of multielement composition of Vranec wines using microwave digestion for sample preparation and inductively coupled plasma mass spectrometry (ICP-MS) was optimized and validated. Best recoveries, ranging from 87 to 114 %, were obtained for all analyzed elements, using a volume of 5 mL wine and 5 mL HNO 3 for sample microwave digestion. In total, 38 elements (Ag, Al, As, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Ge, In, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Pd, Rb, S, Sb, Se, Si, Sn, Sr, Te, Ti, Tl, V, Zn) were determined in wines. The calibration curves of all elements were linear with correlation coefficients (R 2 ) ranging from 0.9920 for 11 B to 1.0000 for 53 Cr and 88 Sr. The accuracy of the method was checked with a standard addition method showing good repeatability and reproducibility (relative standard deviation, RSD <10 %). Vranec wines were fermented with Saccharomyces cerevisiae yeast strains commercial Clos, RC212, D254, and BDX, and six autochthonous Vinalco yeasts. The content of total elements in all Vranec wines ranged between 348 to 678 mg/L, observing lower amounts in wines fermented with the autochthonous Vinalco yeast. The content of harmful elements, such as Pb and Cu, was below the maximal allowed concentration in all wines.

Cryoprotectants are known as substances that are used for protection of biological tissue from freezing damage. Among the most important cryoprotectants are carbohydrates such as glucose, fructose, sucrose raffinose, starch. Starch is a carbohydrate commonly found in the plant tissue, and its concentration is in close relationship with other carbohydrates. This study is about determination of the starch concentration in four Vitis vinifera varieties: Vranec and Smederevka (subconvarietas balcanica Negr.) and Cabernet sauvignon and Chardonnay (subconvarietas gallica Negr.). The concentration of starch in vines is related to their point of cold hardiness. The study shows that the concentration of starch in balcanica varieties is lower than in gallica varieties. Therefore, the Vranec and Smederevka grapevine varieties are not resistant to low temperatures against varieties Cabernet sauvignon and Chardonnay which are tolerant.

SažetakCilj ispitivanja je proučavanje uticaja i pravilan izbor sorte vinove loze i pronalaženje, usavršavanje i primena najpovoljnijih tehnoloških postupaka i načina proizvodnje na kvalitet jakih alkoholnih pića od grožđa. Ispitivane su sorte vranac i smederevka koje su masovno zastupljene u Makedoniji kao i stona sorta afus ali koja je ispitivana i u cilju proizvodnje rakije. Proučavani su različiti tipovi primenjenih tehnologija kod proizvodnje 3 tipa grožđanih rakija i to: vinovica, lozova i komova rakija. U tom kontekstu ispitivan je efekat finog vinskog taloga na kvalitet rakije vinovice, uticaj prisustva peteljke i vremena destilacije na kvalitet lozovе i komove rakije. Izvedena ja hemijska analiza i gasna hromatografija; rakije su senzorno ocenjene i utvrđen je efekt tehnoloških postupaka na senzorna svojstva grožđanih rakija.Ključne reči: vreme destilacije, gasna hromatografija, senzorna analiza UvodHumana populacija bilo koje rase, religije, imovnog stanja ili ideološke grupacije, konzumira različite tipove alkoholnih pića. Naklonjenost pojedinih nacija prema određenom tipu alkoholnog pića je često

This research studies the copper contents in vineyard soils under vineyards affected by the long-term use of copper-based fungicides and evaluates the extent of this influence on the super accumulation in the main viniculture growing regions in North Macedonia. The soil samples were taken from individual vineyards located in the Tikvesh region, from two depths: 0-30 and 30-60 cm. At the same time, control samples were collected from each of the visited sites. The control samples were taken from untreated nearby locations under natural conditions in order to determine the background concentrations. The available copper (Cu) contents were analysed on soil samples taken from 100 locations, 50 of which represent vineyard soils (organic and conventional farming) and 50 control samples from nearby forests and sites. The main finding is that the average available copper concentrations are significantly higher in soils under vineyards, compared to the background concentration in control samples, especially in these with organic farming where the use of coper-based fungicides is more intensive. A comparison of the copper contents in vineyards to the background concentrations of control samples clearly confirmed the anthropogenic influence. A significantly very high level of copper (10.70-18.77 mg/kg) was measured in the soil samples from organic farming. The control samples contained a significantly lower concentration of copper, between average 1.39- 1.62 mg/kg (0-30 cm) and 0.68-0.88 mg/kg (30-60 cm). According to the micronutrient rating as related to a soil test with the DTPA extraction reagent (Jones, 2001) applied in this study, a significant potential ecological risk has been noticed in the agricultural soil samples (organic and conventional production).