The aim of the present study was to determine polyphenolic composition, related antioxidative and antimicrobial properties of grape skin extracts from 14 grape varieties (seven white and seven red ...grape) grown in Dalmatia (Croatia). The content of total phenols, flavonoids, catechins, flavanols and individual polyphenols ((+)-catechin, (−)-epicatechin, epicatechin gallate, procyanidin B1 and procyanidin B2, quercetin glucoside, resveratrol monomers, piceid and astringin) was variety dependent. Antioxidant properties were determined as DPPH radical-scavenging ability (
IC
50), ferric reducing/antioxidant power (FRAP), Fe
2+-chelating activity (
IC
50), and using β-carotene bleaching assay. The high antioxidant capacity of all extracts, both red and white, has been observed and related to the relative amounts of polyphenolic compounds with good antioxidant properties. The antimicrobial activity was screened by broth microdilution test using Gram-positive (
Staphylococcus aureus,
Bacillus cereus) and Gram-negative bacteria (
Escherichia coli O157:H7,
Salmonella Infantis,
Campylobacter coli). It was confirmed against all tested organisms. Minimum inhibitory concentrations (
MICs), were found in the range 0.014–0.59
mg of gallic acid equivalents (GAE)/ml, with lower
MICs of white cultivars, especially against
Campylobacter and
Salmonella.
The seasonal and spatial distributions of particulate phosphorus (PP) in the water column of the coastal area and open sea of the middle Adriatic Sea area were investigated for the first time. The ...relationship between PP and two other important forms of phosphorus (dissolved inorganic phosphorus (DIP), and organic phosphorus (P-ORG)), and the relationship between PP and other nutrients (nitrogen and silicon salts) and oceanographic parameters (temperature, salinity, oxygen saturation, chlorophyll a) from the water column were also examined. PP concentrations ranged from 0.007 μmol dm-3 in the open sea near Palagruža archipelago to 0.589 μmol dm-3 in the Krka River estuary. In the coastal area, PP concentrations were highest in autumn and lowest in winter. The vertical distribution of PP concentrations in the water column of the coastal area were highest in the surface layer during most of the year due to input of PP by freshwater inflows. In the open sea area, there were no significant seasonal or vertical differences in the distribution of PP concentrations in thewater column. Seasonal analysis of the total phosphorus pool (PP, DIP and P-ORG) in the water column indicated that PP and P-ORG concentrations were higher in the coastal area compared to the open sea, while DIP concentrations were comparable.The results further demonstrate that PP can be an important fraction of the total phosphorus pool. A significant positive correlation was found between PP and chlorophyll a, indicating that PP was mainly of biological origin, and with nutrient salts of nitrogen and silicon, while a negative correlation was found with salinity.
Sezonska i prostorna raspodjela partikularnog fosfora (PP) istraživana je u vodenom stupcu obalnog i otvorenog mora srednjeg Jadrana po prvi put. Istražen je i odnos PP-a s drugim važnim oblicima fosfora (otopljeni anorganski fosfor (DIP) i organski fosfor (P-ORG)), kao i odnos između PP-a i ostalih nutrijenata (soli dušika i silicija) ioceanografskih parametara (temperatura, salinitet, zasićenost kisikom, klorofil a) iz vodenog stupca. Koncentracije PP-a su bile u rasponu od 0.007 μmol dm-3 na otvorenom moru kod otočja Palagruže do 0.589 μmol dm-3 u estuariju rijeke Krke. Uobalnom području srednjeg Jadrana najviše koncentracije PP izmjerene su tijekom jeseni, a najniže tijekom zime. Vertikalna raspodjela koncentracija PP-a u vodenom stupcu obalnog područja pokazala je najviše vrijednosti u površinskom sloju tijekomvećeg dijela godine, što je posljedica unosa PP-a slatkovodnim dotocima. U području otvorenog mora nisu utvrđene značajne razlike u sezonskoj i vertikalnoj raspodjeli koncentracija PP u vodenom stupcu. Rezultati sezonskih istraživanja ukupnog fosfora u vodenom stupcu (PP, DIP i P-ORG) pokazala su da su koncentracije PP-a i P-ORG-a više u obalnom području u odnosu na koncentracije zabilježene u području otvorenog mora, dok su koncentracije DIP usporedive u oba područja. Rezultati također ukazuju da PP može imati važan udio u ukupnom fosforu. Statistička analiza rezultata pokazalaje značajnu pozitivnu korelaciju PP-a s klorofilom a, što ukazuje da je PP uglavnom biološkog podrijetla, kao i s hranjivim solima dušika i silicija; dok je negativna korelacija utvrđena sa salinitetom.
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).
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.
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.
U ovome radu prikazane su osnovne vinogradarske i enološke karakteristike cv. Pinot sivi iz vinogorja Imotski. Proces proizvodnje pjenušavoga vina proveden je prema konvencionalnoj metodi sekundarne ...alkoholne fermentacije u boci. Stupanj zrelosti grožđa u trenutku berbe bio je niži u odnosu na uobičajenu praksu za proizvodnju mirnih vina. Osnovno vino bilo je suho (šećer 1,5 g/L), sadržaj stvarnog alkohola bio je 11,6 vol % i ukupna kiselost 7,1 g/L (pH 3,17). Procesom re-fermentacije stvarni se alkohol povisio za 0,9 vol. %, a nastali ugljični dioksid stvorio je pritisak od 5 bara. Metodom plinske kromatografije identificirano i kvantificirano je osam hlapljivih ″fermentativnih″ komponenti arome pjenušavoga vina. Na osnovi dobivenih rezultata, može se utvrditi da u vinogorju Imotski postoje prikladni klimatski uvjeti za proizvodnju pjenušavih vina.
The aim of this study was to establish the relationship between the large groups of polyphenols (total phenols, total anthocyanins, low molecular weight proanthocyanidins as well as high molecular ...weight proanthocyanidins) and sensory perception of native Croatian red wine Babić.Sensory evaluation of four types of wines produced at different pomace contact times and temperatures was conducted by 11 panellists who rated the intensity of astringency, bitterness and overall sensory impression of each wine. Complex observations of sensory and analytical values (using principal component analysis, PCA) indicate the acceptability of the wine. In order to compare the obtained results, chemometric methods, particularly principal component analysis (PCA), were conducted for sensory evaluation of the data and identification of wine. Analysis of the score plot of the PCA for the monitored values showed that over 85% of the total variance in the data can be described by PC 1 and PC 2. Results of this study demonstrate a strong correlation between the concentration of polyphenols and the sensory attributes. Decreasing macerationtemperature leads to the best perception of astringency and overall impression in younger wines. Prolongation of pomace contact time resulted in the best attributes of astringency, bitterness and overall impression in aged wines.
Sixteen native central Dalmatian grapevine cultivars were characterised at eight SSR loci and eighteen primary morphological descriptors. The present work describes for the first time twelve native ...Dalmatian cultivars with morphological and molecular descriptors. One pair of synonyms was determined (‘Babić’/’Rogoznička’), and the other previously assumed pair (’Crljenak Kaštelanski’/’Pribidrag’) was verified. The remaining cultivars showed unique SSR genotype and seemed to be different from any other previously described Croatian cultivars. The results of SSR characterisation suggested the possibility of parent-offspring relationship between ’Babić’ and ’Dobričić’ and between ’Plavac Mali’ and ’Babica’. Phenotypic relationship among cultivars based on morphological data (d-values) was determined according to original mathematical algorithm. The d-value proved to be informative and showed rather clear ability to discriminate between Dalmatian cultivars. Significant but weak correlation (r = -0.38) was observed by comparing the similarity matrices obtained from morphological and SSR data using the Mantel test.
Total acidity was determined in thirty-seven samples of Croatian red, white and rosé 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–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.
