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The δ18O and δ13C (analyzed by isotope ratio mass spectrometry, IRMS) and concentration of 22 selected elements (analyzed by inductively coupled plasma—optical emission spectrometry, ICP-OES) in 190 Croatian microvinified and commercial wine samples from continental and coastal winegrowing areas and from three viticultural zones (B, CI, and CII) were measured to investigate whether multivariate statistical methods could provide the fingerprint for geographical origin determination. The highest power for discrimination of wines produced in Croatian winegrowing areas was achieved by general discriminant analysis (GDA) showing correct classification of 97.9% of all investigated samples, 100.0% of microvinified samples and 84.8% of commercial samples in the cross-validation matrix. The most significant markers for discrimination of coastal and continental areas found by GDA were δ18O and Co, followed by K, Rb, Sn, Li, and δ13C in descending order. GDA showed higher levels of correctly classified samples from three viticultural zones in Croatia if only microvinified samples were employed in the analysis (94.9%) than for all samples together (86.3%) or for commercial samples (66.1%) in the cross-validation matrix. The discrimination of viticultural zones B, CI, and CII in Croatia was achieved by δ18O, Co, Rb, Li, K, and Sn. The results obtained showed that the relationships between the isotopic ratios and concentrations of different considered elements combined with appropriate statistical model represent a powerful tool in discrimination of wines produced in different Croatian winegrowing areas.

The aim of this study was to evaluate the impact of the macerating enzyme addition (Sihazym Extro and Vinozym Vintage) on the extraction of phenolics, colour components, and antioxidants in Babica wine. Spectrophotometry was used for determination of total phenolics, anthocyanins, and wine colour parameters (intensity, hue, and chromatic structure); the individual phenolics were detected using HPLC; while reducing and free radical scavenging activities of the samples were analysed using the FRAP and DPPH assays. The results indicate a more favourable effect of the Sihazym Extro on the extraction of phenolics, while both enzymes improved the extraction of anthocyanins during the maceration. The most abundant phenolic compounds were malvidin derivatives whose concentration continuously increased during the vinification and reached 82% of all anthocyanin derivatives in the control wine and 81% in both enzyme-treated wines. As expected, the antioxidant activity of the samples followed the trend of phenolics content growth and increased during the vinification, resulting in the higher activity of the enzyme-treated wines.

Food safety is one of the main concerns in the world and in wine it depends mostly on metabolites of microbial origin. The aim of this study was to investigate the occurrence of natural contaminants, ochratoxin A and biogenic amines (cadaverine, histamine, putrescine and tyramine), in Croatian commercial red wines originating from different Croatian wine-making regions. Ochratoxin A was detected in 92.8% of samples, however its concentrations in all samples were more than 10-fold lower than the limit set by the European Union (2 &micro, g/kg), marking these wines as safe for consumption. The frequency of occurrence and measured concentrations of ochratoxin A were higher in wines produced in southern regions with highest values obtained in wines from southern Dalmatian islands. All samples were contaminated with cadaverine and putrescine, while 88.2% and 82.7% were contaminated with histamine and tyramine, respectively. Histamine concentrations ranged from below the limit of detection to 8.5 mg/L. Higher histamine concentrations were measured in wines with higher pH values which coincided with southern geographic origin. These results reinforce the need for routine detection and quantification of biogenic amines in Croatian wines to achieve better control of vinification and minimize their formation.

Crljenak kastelanski or Tribidrag is a Croatian autochthonous grape variety which is a parent of the America’s most popular variety Zinfandel or Italian Primitivo. The aim of this study was to investigate the dynamics of extraction of phenolics and changes in antioxidant activity of the samples collected during maceration of C. kastelanski grapes processed using two different macerating enzymes. According to the obtained results it can be concluded that wines from C. kastelanski grapes are great source of bioactive phenolics although differences in phenolic profiles between control and enzyme-treated wines were detected. The highest content of total phenolics was detected in control wine (2691 mg GAE/L). Use of pectolitic enzyme Vinozym Vintage improved anthocyanin extraction, while higher colour parameters were observed for wine samples produced using Sihazym Extro. The statistical analysis confirmed great influence of total phenolics and concentrations of some individual phenolic compounds (e.g. catechin, gallic acid, epicatechin) on reducing and free radical scavenging activity of wine samples while the impact of anthocyanins was not detected. According to the obtained results it can be concluded that use of enzymes has slightly negative effect on total phenolics and wine antioxidant properties, but it increases the extraction yield of wine colour components what enables shorter maceration and prevents colour losses during the aging process.

Nowadays, incidents related to intentional contamination of food products are a huge problem in the whole food supply chain. Therefore, it is necessary to raise awareness of food defence at every level of the food chain, from farm to fork, from government and academic institutions to retail chains, the media and consumers. The principles of food defence can be implemented at every level of the food chain. Food defence contributes to the mitigation of potential risks in intentional contamination and food fraud, which can have a harmful effect on humans and public health, business, economy, etc. The requirement for the implementation of food defence comes from retail chains. They require food companies to be certified according to the standards of the food safety system such as those supported by the Global Food Safety Initiative. Although food defence is an inevitable step in enhancing and strengthening the whole food safety system, on a global scale, an insufficient number of countries have incorporated food defence principles into their legal frameworks. The intention of this review article is to increase awareness of food defence in food industry.

Volatile aroma compounds production by two autochthonous Saccharomyces cerevisiae strains, isolated from Istria region, and three other yeast strains (Saccharomyces bayanus and two commercial Saccharomyces cerevisiae wine yeasts) was investigated on a small scale using synthetic VP4 medium and Graševina must at 12 and 20°C. The results obtained by gas chromatography analyses were compared with the aroma production properties of the native microflora, remaining after Graševina must sulphiting. In both media and at both temperatures, the wine yeasts investigated showed different metabolic profiles regarding the tested volatile aroma compounds, which should be taken in consideration for autochthonous wine production. Although the synthetic medium proved to be appropriate for the investigation of the fermentative properties, the determination of secondary aroma production by wine yeasts has to be conducted by must fermentation or possibly by fermentation of another synthetic medium whose composition would be more similar to must.

Solid-phase microextraction (SPME) was examined to investigate volatiles in tomatoes and tomato products. Aroma volatiles and differences in volatile composition of different varieties of fresh tomatoes and several commercial tomato products, such as tomato juice, tomato puree, tomato paste and canned diced tomatoes, were analysed by a manual headspace SPME technique coupled with gas chromatography (GC–FID and GC–MS). Fresh and processed tomato aroma was composed of terpenes and lactones, esters, carbonyls and alcohols, sulphur compounds, free acids and oxygencontaining heterocyclic compounds. In most samples of processed tomatoes, lower relative concentrations of volatiles than in fresh tomato samples were determined, but in some cases (especially in samples of tomato juice) higher concentrations were observed. The most important difference between fresh tomato and processed tomato aroma was the almost complete loss of cis-3-hexenal and the presence of furfural in tomato products. On the basis of the aromatic profiles obtained by GC analysis, relationships between fresh and processed tomato samples were obtained, using multivariate PCA statistical analysis. Copyright © 2007 John Wiley & Sons, Ltd.

The influence of the addition of two sugars (trehalose and sucrose) on the retention of volatiles responsible for the characteristic aroma in dehydrated apricot puree was studied. Aroma compounds of fresh and both freeze dried and foam-mat dried apricot puree were analyzed by manual headspace solid-phase microextraction (SPME) coupled with gas chromatography (GC-FID and GC-MS). The best retention of aroma compounds in dehydrated apricot puree was obtained when trehalose was added, regardless of the dehydration process used (freeze drying or foam-mat drying) although, generally, a much higher retention of flavour volatiles was obtained in freeze dried purees. Principal Component Analysis (PCA) and Cluster Analysis (CA) were applied to all apricot purees studied to obtain a more simplified view of the relationship among the aroma compounds in dehydrated apricot purees. This study gives further insights into the mechanisms that occur when trehalose is applied as an additive and will enable the development of new processes to maximize this effect and to produce superior dried products.

The prospects of quality young wine distillates production have been examined. The base wine was produced from Vitis vinifera L. quantitatively dominating grape varieties within the group of the recommended and permitted varieties of Kutjevo vineyards, located in the eastern part of the continental Croatia. Characterisation of wine and distillates was based on chemical and instrumental methods and on their sensory evaluation. Volatile compounds were analysed and identified by GC-FID and GC-MS. The wine varieties Rhine riesling, Müller Thurgau and Riesling have the potential for the production of quality distillates, suitable for maturation. Pinot white, Traminer and Chardonnay give more acceptable wines than distillates and it is therefore not advisable to use them for distillates production, while the varieties Pinot gris, Frankovka and Steinschiller are not suitable for the production of distillates.

The phytic acid content and distribution of phosphorous during cereal flaking were determined as well as the level of some minerals, and the molar ratios of phytic acid ; zinc were calculated. statistical analyses showed that there were no differences in the amount of total phosphorous, between oats and wheat and between rye and barley. The phytic/non-phytic phosphorous ratio was about 3 in wheat and oats, about 2 in barley and about 13 in rye. The technological processing did not affect P

Knowledge of the content of heavy metals is important because of their impact on the stability of wine or on the health of consumers. The presence of heavy metals in wines is a consequence of action various factors such as conditions of cultivation and processing of grapes and production, stabilization or storage of wine. In this work determination of heavy metals (Cu, Fe, Zn and Pb) content in red wines was carried out. Selected wine was Plavac mali, Croatian autochthonous sort, produced by various producers during the three consecutive vintages. The aim of this work was to examine whether the wines produced in different vintage, and by various producers, vary according the content of heavy metals. To determination of heavy metals content, atomic absorption spectrometry (AAS) was used. Content of heavy metals ranged between 0, 235-1, 122 mg/L (Cu), 0, 809 – 6, 202 mg/L (Fe), 0, 266-2, 434 mg/L (Zn) and 0, 107 - 0, 3355 mg/L (Pb). Data analysis showed statistically significant differences only between producers for iron and copper content.