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This paper evaluates the effect of must hyperoxygenation on final wine. Lower concentrations of caftaric acid (0.29 mg·L -1 ), coutaric acid (1.37 mg·L -1 ) and Catechin (0.86 mg·L -1 ) were observed in hyperoxygenated must in contrast to control must (caftaric acid 32.78 mg·L -1 , coutaric acid 5.01 mg·L -1 and Catechin 4.45 mg·L -1 ). In the final wine, hydroxybenzoic acids were found in higher concentrations in the control variant (gallic acid 2.58 mg·L -1 , protocatechuic acid 1.02 mg·L -1 , vanillic acid 2.05 mg·L -1 , syringic acid 2.10 mg·L -1 ) than in the hyperoxygenated variant (2.01 mg·L -1 , 0.86 mg·L -1 , 0.98 mg·L -1 and 1.50 mg·L -1 respectively). Higher concentrations of total flavanols (2 mg·L -1 in hyperoxygenated must and 21 mg·L -1 in control must; 7.5 mg·L -1 in hyperoxygenated wine and 19.8 mg·L -1 in control wine) and polyphenols (97 mg·L -1 in hyperoxygenated must and 249 mg·L -1 in control must; 171 mg·L -1 in hyperoxygenated wine and 240 mg·L -1 in control wine) were found in both the must and the control wine. A total of 24 volatiles were determined using gas chromatography mass spectrometry. Statistical differences were achieved for isobutyl alcohol (26.33 mg·L -1 in control wine and 32.84 mg·L -1 in hyperoxygenated wine), or 1-propanol (7.28 mg·L -1 in control wine and 8.51 mg·L -1 in hyperoxygenated wine), while esters such as isoamyl acetate (1534.41 µg·L -1 in control wine and 698.67 µg·L -1 in hyperoxygenated wine), 1-hexyl acetate (136.32 µg·L -1 in control wine and 71.67 µg·L -1 in hyperoxygenated wine) and isobutyl acetate (73.88 µg·L -1 in control wine and 37.27 µg·L -1 in hyperoxygenated wine) had a statistically lower concentration.

This study deals with the effects of the use of a mixture of medium-chain fatty acids (MCFA) at the end of the alcohol fermentation process on the content of carbonyl compounds in wine. During the experiment, the effects of the addition of MCFA at doses of 10 and 20 mg/L were compared to the termination of alcohol fermentation using cross-flow filtration and chilling treatments. Individual carbonyl compounds were determined by HPLC analysis. The experiment showed that the addition of MCFA caused a reduction of the acetaldehyde content compared to the chilling process, and a reduction of the diacetyl content compared to cross-flow filtration. Throughout the experiment, a lower level of total carbonyl compounds was observed after the addition of MCFA.

Nanotechnology is one of the most promising future technologies for the food industry. Some of its applications have already been introduced in analytical techniques and food packaging technologies. This review summarizes existing knowledge about the implementation of nanotechnology in wine laboratory procedures. The focus is mainly on recent advancements in the design and development of nanomaterial-based sensors for wine compounds analysis and assessing wine safety. Nanotechnological approaches could be useful in the wine production process, to simplify wine analysis methods, and to improve the quality and safety of the final product.

Wine consumption has been popular worldwide for many centuries. Based on in vitro and in vivo studies, a certain amount of everyday wine consumption may prevent various chronic diseases. This is due, in part, to the presence and amount of important antioxidants in red wine, and, therefore, research has focused on them. Wine polyphenols, especially resveratrol, anthocyanins, and catechins, are the most effective wine antioxidants. Resveratrol is active in the prevention of cardiovascular diseases by neutralizing free oxygen radicals and reactive nitrogenous radicals; it penetrates the blood-brain barrier and, thus, protects the brain and nerve cells. It also reduces platelet aggregation and so counteracts the formation of blood clots or thrombi. The main aim of this review is to summarize the current findings about the positive influence of wine consumption on human organ function, chronic diseases, and the reduction of damage to the cardiovascular system.

This paper deals with a study of the inhibition of microorganisms occurring in grape must and wine, using silver in the form of nanoparticles and colloidal solution. Pure cultures of yeasts Saccharomyces cerevisiae and Brettanomyces bruxellensis, lactic acid bacteria Lactobacillus brevis, Pediococcus damnsosus and acetic acid bacteria Acetobacter aceti and Gluconobacter oxydans were used for the experiments. Attention was primarily focused on monitoring changes in carbohydrate processing, namely glucose, fructose, sucrose, maltose, mannitol, galactose, trehalose, and ß-glucosidase activity. These biochemical determinations have shown limitations in carbohydrate processing, particularly sucrose in yeasts, and fructose, glucose and sucrose in bacteria. The effects of silver have also been observed in natural microflora found in grape must from Chardonnay and Hibernal. Colloidal silver at concentrations 40, 70 and 100 ppm and silver nanoparticles at concentrations 70, 150 and 250 ppm were used for inhibition. A plate method was used to determine the number of viable colonies. With an increasing concentration of applied substances, the growth of both yeasts and bacteria was strongly inhibited, as indicated by the numbers of colonies cultivated from the must. Yeast growth was inhibited by the lowest concentration -- (70 ppm) by up to 72% and bacterial growth by up to 75.5%. [ABSTRACT FROM AUTHOR]

The presented study is focused on the determination of the content of terpenic substances in grapes and subsequently produced a wine of Czech variety Pálava (the Czech Republic, wine region Morava), which is a protected landscape with long-term tradition and culture. The aim of this study was the analysis of the aromatic profile of the cultivar Pálava, which was fermented by the original yeast strains from the Moravian wine region. Larger amounts of flavoring substances occur in grapes as bound flavoring substances, most often in the form of glycosides. One of the basic groups of aromatic substances is monoterpenes. The content of twelve free and bound terpenic substances was measured by the GC-MS method, namely linalool, ho-trineol, a-terpeniol, β-citronellol, nerol, geraniol, furan linalool oxide 1, furan linalool oxide 2, nerol oxide, epoxylinalol 1, epoxylinalol 2 and 2,6-dimethyl-3,7-octadiene-2,6-diol. The results were statistically compared by using a simple descriptive statistical method and ANOVA method. We noted a difference between the content of free and bound terpenes was very significant (p ≤0.05). We found that using uncommercial yeasts could have an effect on the content of the volatile and terpenic compounds in wines. An important finding was that in fresh berry extracts there was a higher proportion of bound terpenes than free terpenes. The results have shown that the production technology of wine and the fermentation process has a clear impact on the content of the substances. [ABSTRACT FROM AUTHOR]