Prosek is a traditional dessert wine from the coastal region of Croatia made from partially dried grapes. There is very little literature data about the chemical composition and sensory properties of ...Prosek, so an experimental production from the dried grapes of Plavac mali cultivar has been done using native and induced alcoholic fermentations. To determine the volatile compounds, gas chromatography with flame ionisation detector (GC/FID) was used on the samples prepared with solid phase microextraction (SPME). Higher alcohols, esters, carbonyl compounds and volatile acids were determined in the wine samples. Wines were grouped according to the production method using principal component analysis (PCA). It was found that Prosek wines produced with native and induced alcoholic fermentation differ in their volatile compounds. Descriptive sensory analysis was applied to show the sensory properties of Prosek wine, whose characteristic aromas include those of dried fruit (raisins), red berries, honey, chocolate and vanilla. A significant difference depending on the type of fermentation was determined in two sensory attributes, strawberry jam aroma and fullness. Key words: Prosek, dessert wine, fermentation, volatile compounds, descriptive sensory analysis
Aims:A four-year study (2007 through 2010) was carried out to determine agronomic, biological, and oenological characteristics of Dobričić grapevines so as to evaluate this cultivar and protect it ...from extinction. Methods and results: 38 characteristics from the OIV descriptor list were used to describe young shoot, mature leaf, cluster, and berry morphology of Dobričić grapevines. The dimensions of an average leaf were constructed from measured leaf variables. A typical Dobričić genotype at nine microsatellite loci is presented. ELISA analysis revealed high virus incidence and all samples tested were GLRaV-3 positive. The profile of different classes of polyphenols in Dobričić wine was determined using HPLC and spectrophotometry. The concentrations of polyphenols in Dobričić wine, especially anthocyanins, hydroxycinnamic acids and stilbenes, were high compared to major red wines reported in the literature. Descriptive sensory analysis was carried out to determine the aroma attributes describing a Dobričić monovarietal wine. Conclusion: Knowledge of the biodiversity of the grapevine cultivars of Croatia is still scant. This study provides for the first time ampelographic and oenological information on Dobričić grapevines and demonstrates its high quality potential. Significance and impact of the study: The results of the ampelographic characterization would be helpful in the identification and selection of Dobričić for cultivation in certain vine-growing areas. The outstanding quality of Dobričić makes it very promising for wine blending (colour improvement) and plant breeding purposes.
This research aimed to analyze the impact of two different non-Saccharomyces yeast species on the aromatic profile of red wines made from the cv. Babić (Vitis vinifera L.) red grape variety. The ...grapes were obtained from two positions in the Middle and South of Dalmatia. This study compared a control treatment with the Saccharomyces cerevisiae (Sc) strain as a type of sequential inoculation treatment with Lachancea thermotolerans (Lt x Sc) and Torulaspora delbrueckii (Td x Sc). The focus was on the basic wine parameters and volatile aromatic compound concentrations determined using the SPME-Arrow-GC/MS method. The results revealed significant differences in cis-linalool oxide, geraniol, neric acid, and nerol, which contribute to the sensory profile with floral and rose-like aromas; some ethyl esters, such as ethyl furoate, ethyl hexanoate, ethyl lactate, ethyl 2-hydroxy-3-methylbutanoate, ethyl 3-hydroxy butanoate, diethyl glutarate, and diethyl succinate, contribute to the aromatic profile with fruity, buttery, overripe, or aging aromas. A sensory evaluation of wines confirmed that Td x Sc treatments exhibited particularly positive aromatic properties together with a more intense fullness, harmony, aftertaste, and overall impression.
Anthocyanins are dietary bioactive compounds showing a range of beneficial effects against cardiovascular, neurological, and eye conditions. However, there is, as for other bioactive compounds in ...food, a high inter and intra-individual variation in the response to anthocyanin intake that in many cases leads to contradictory results in human trials. This variability could be caused at two levels, one at the bioavailability level and the other at the effect and mechanisms of action. In this context, we have thoroughly reviewed the scientific literature on anthocyanins variability caused by variation in bioavailability. Based on the literature reviewed, we have concluded that the variability in anthocyanins bioavailability might be produced by the lack of homogeneity introduced at three different levels: food matrix and food processing, enzymes involved in anthocyanin metabolism and transport, and anthocyanin metabolizing gut microbiota. However, it should be noted that the literature on anthocyanins bioavailability considering inter or intra-individual variability is still very scarce, which makes it difficult to reach any firm conclusion on the main metabolizing enzymes or bacteria that would be responsible for the variability in anthocyanin bioavailability.
Effects of winemaking techniques on the polyphenolic composition of specific Croatian wines made from Babić (Vitis vinifera, L.), from the Primošten vine-growing region, were subjected to ...examination. Winemaking processes and reactions that take place during maturation significantly influence the content of anthocyanins and proanthocyanidins in wine. Prolonged maceration duration caused an increase in the content of total phenols, vanillin index and proanthocyanidins, as well as a decrease in the content of anthocyanins in young wine. Cold maceration brought about a decrease in anthocyanins, total phenols and proanthocyanidins in Babić wine. The effects of winemaking techniques on the index of vanillin and proanthocyanidins in wines maturated for 6 and 14 months were significant.
The eessential viticultural and oenological characteristics of cv. Pinot gris originated from viticultural area of Imotski were investigated. The sparkling wine was produced by the conventional ...method of secondary alcoholic fermentation in bottle. The degree of grape maturation at the harvest time was lower compared to the common practices of still wine production. The base wine was dry (sugar 1.5 g/L), content of actual alcohol was 11.6 vol. % and total acidity 7.1 g/L (pH 3.17). Re-fermentation process induced higher level of alcohol by 0.9 vol. % and carbon dioxide formed of five bars pressure. Eight volatile “fermentative” aroma compounds of sparkling wine were determined and quantified by using method of gas chromatography. According to the showed results it could be considered that climatic conditions in viticultural area of Imotski are suitable for sparkling wine production.
Identification of phenolic acids was performed and changes in their content during the production of autochthonous Croatian white wines Pošip and Rukatac (Vitis vinifera, L.) were registered. In both ...varieties (Pošip, Rukatac) the following phenolic acids were identified: gallic, protocatechuic and vanillic acids as hydroxybenzoic acids; and caffeic, p-coumaric and ferulic acids as hydroxycinnamic acids. It was found that there is a difference between hydroxybenzoic acid group and hydroxycinnamic acid group content and between their influences on the wine colour (colour intensity and hue).
The influence of different maceration techniques on the dynamics of polyphenol extraction during the maceration of the autochthonous Croatian grape Babic has been investigated. The process of wine ...production by maceration in traditional procedure and by maceration with advanced technique has been compared. During maceration, the dynamics of extraction of total anthocyanins, total phenols, low-molecular proanthocyanidins and high-molecular proanthocyanidins was determined. Mathematical models are proposed for each above mentioned and determined parameter. The models present the values under observation depending on treatment - traditional or modern. Time expressed in days is the input variable for both monitored models. Presented models indicate a significant positive correlation and strongly sustain the concept that the duration and procedure of maceration have considerable influence on the measured variables (R=0.83-0.98).
Total acidity was determined in thirty-seven samples of Croatian red, white and rose wines by potentiometric titration. In order to find the effect of the corresponding rate of the automatic titrant ...added, several procedures were employed. For different rates of titration, the aberrances were found from 0.1 to 0.4 g L super(-1) for some wines. The value of the total acid content in wine determined by the automatic potentiometric titration method was compared to that obtained by the conventional volumetric titration method. The ANOVA and cluster analysis (CA) were applied to detect possible resemblance. The results of total acidity depended on the methods used. However, a good correlation between the results by these methods was found.
NIRS has been applied for the analysis of dessert wine Prošek produced from dried grapes of Pošip and Plavac mali cv. in a semi-scaled fermentation. It is a fast and non-destructive analytical method ...that in association with chemometrics is becoming more frequently used technique. NIR spectra were measured and the relative density, alcohol content, dry extract, reducing sugars, pH, total acidity, volatile acidity, ash, free sulphur dioxide and total sulphur dioxide were determined. The range of NIRS used in this paper was 904–1699 nm (i.e. 11062–5886 cm−1) because in this range vibrations of C–H, O–H, S–H and N–H bonds can mainly be observed. Using the basic principles of multivariate analysis, principal component analysis (PCA), was used to reduce the input matrix in order to look for significant relationships between the NIR spectra and the observed characteristics of wine Prošek. Chemometrics applied here resulted in further discrimination between samples. The main features of the spectra are absorption bands at 1580 and 1670 nm, which are related to the first overtone of the C–H stretch. Absorption bands around 908 nm, present the stretches related to the 3rd C–H overtone and 2nd overtone of the O–H stretch of H2O and ethanol. PC1 and PC2, the first two components, gave the highest level of classification (≈95 %) based on the grape used for wine production as well as on the added yeast. The potential of NIRS, as a non-destructive method, is screening of basic parameters that are usually determined during the winemaking and ageing of wine. The results of investigations confirm that NIRS combined with chemometric analysis is a promising tool for quality control and for on-line application in the control of the final product, Prošek.
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