Effect of the Application Time of Accentuated Cut Edges (ACE) on Marquette Wine Phenolic Compounds

Cold-hardy interspecific hybrid grape varieties (Vitis spp.) have distinctive chemical compositions such as high acidity, a high content of anthocyanin diglucoside and a low condensed tannins content, compared to Vitis vinifera varieties. Considering the importance of phenolic compounds on the quality of red wine, a mechanical maceration technique, accentuated cut edges (ACE), has been evaluated when applied directly to crushed grapes (ACE-C), and 24 h before pressing (ACE-P), to improve the extraction of phenolic compounds. Samples were collected at crushing, bottling, and after five months of aging. Phenolic compounds and color characteristics of the wines were analyzed by high-performance liquid chromatography (HPLC) with diode array and fluorescence detectors and UV-Visible spectrophotometry. The color intensity, non-anthocyanin monomeric compounds and total iron-reactive phenolics content increased after applying ACE, compared to the control (CTL) after aging, and was significantly higher (37%) after ACE-C, compared to ACE-P. However, the concentration of condensed tannins was below the limit of detection in all the samples, indicating that ACE did not help their extraction or further interactions occurred with disrupted cell wall material. Applying ACE at crushing was considered as the optimum time to achieve a higher color stability in Marquette red wines.

Enzymatic pre-treatment of grape seeds for an oil with higher antioxidant activity

The paper investigates the effect of the enzymatic pre-treatment of grape seeds from six Romanian cultivars on the oil extracted. The grape seeds of some white and red Romanian grape varieties were separated from winery waste, washed, dried and ground, with the oil then obtained by extraction with petroleum ether. The extraction was performed directly or after a preliminary treatment with a commercial pectin lyase. The enzymatic procedure applied was more cost effective compared to other treatments previously described in which a cocktail of enzymes was used. The quantity of the extracted oil was measured in both types of processing, with an increase being observed for pre-treated samples. The fatty acid profiles (FAPs) of the oils resulted for the treated and untreated seeds were determined. No change in the composition was noticed. The reductive power of these oils was also investigated. Compared to the untreated samples for the same variety, the enzyme pre-treatment resulted in a superior antioxidant capacity.

Potential Associations among Bioactive Molecules, Antioxidant Activity and Resveratrol Production in Vitis vinifera Fruits of North America

Grapes (Vitis vinifera L.) are rich in bioactive molecules contributing to health benefits. Consumption of grapes is linked to reduced incidence of cardiovascular diseases. Studies on table grape cultivars are limited although much attention in research was focused on the wine industry. Bioactive effects of grapes as anti-inflammatory, anticarcinogenic, cardioprotective, vasorelaxant, phytoestrogenic and neuroprotective have also been reported. For example, resveratrol is a natural food ingredient present in grapes, with high antioxidant potential. Here we conducted an exploratory study to investigate bioactive molecules, antioxidant activity and the association between constitutive stilbene synthase (STS) gene expression and the resveratrol biosynthesis in selected table grape varieties in North America. The phenolic compounds, fatty acid composition and antioxidant activity of four grape varieties were compared. Red Globe variety was rich in unsaturated fatty acids as well as phenolic compounds such as caffeic acid, quercetin and resveratrol. Meanwhile, the constitutive expression of grape stilbene synthase gene was higher in Flame and Autumn Royal where resveratrol content of these cultivars was relatively low compared to the Red Globe variety. This study shows the potential links in grape antioxidant activity and resveratrol production, but more studies are necessary to show the association.

Characterization of Musts, Wines, and Sparkling Wines Based on Their Elemental Composition Determined by ICP-OES and ICP-MS

Samples from the different processing stages in the elaboration of sparkling wine (cava)—including must, base wine, and sparkling wine—of Pinot Noir and Xarel·lo grape varieties from different vineyard qualities (A, B, C, D) have been analyzed by inductively coupled plasma (ICP) techniques to determine their elemental composition. The resulting data has been used to characterize these products according to oenological features and product qualities. For this purpose, box plot diagrams, bar charts, and principal components analysis (PCA) have been used. The study of the behavior of each given species has pointed out the relevance of some elements as markers or descriptors of winemaking processes. Among others, Cu and K are abundant in musts and their concentrations progressively decrease through the cava production process. S levels suddenly increase at the base wine step (and further decay) due to the addition of sulfites as preserving agents. Finally, concentrations of Na, Ca, Fe, and Mg increase from the first fermentation due to the addition of clarifying agents such as bentonite. PCA has been applied to try to extract solid and global conclusions on trends and chemical markers within the groups of samples more easily and efficiently than more conventional approaches.

Genetic polymorphism of local Abkhazian grape cultivars

Local grape cultivars from different countries of the world are an important part of the gene pool of this culture. Of particular interest are the genotypes of the most ancient regions of viticulture. The territories of the subtropical zone of Georgia and the central part of Abkhazia belong to one of the centers of origin of the cultural grapevine. The purpose of the work was to genotype native Abkhazian grape cultivars, to study their genetic diversity based on DNA profiling data and to compare them with the genotypes of local varieties of other viticultural regions. Samples of plants were taken on the territory of the Republic of Abkhazia in private farmsteads and in the collection of the agricultural firm “Vina i Vody Abkhazii“ (“Wines and Waters of Abkhazia”). The genotyping of the Abkhazian cultivars Avasirhva, Agbizh, Azhapsh, Azhizhkvakva, Azhikvaca, Atvizh, Atyrkuazh, Achkykazh, Kachich was carried out using 14 DNA markers, 9 of which are standard microsatellite markers recommended for the identification of grape varieties. To improve our knowledge about the sizes of the identified alleles, we used the DNA of grape cultivars with a known allelic composition at the analyzed loci. Statistical analysis of the data showed that the observed heterozygosity for the analyzed loci exceeded expected values, which indicates a genetic polymorphism of the studied sample of varieties. Evaluation of genetic similarity within the analyzed group based on the results of genotyping at 14 loci showed that the cultivars Kachich and Azhapsh differed from the other Abkhazian varieties. The obtained DNA profiles of the Abkhazian cultivars were checked for compliance with DNA-fingerprints of grape varieties in the Vitis International Variety Catalogue. The Georgian varieties Azhizhkvakva and Tsitska turned out to be synonyms according to DNA profiles, two varieties from the Database (Italian Albana bianca and Georgian Ojaleshi) have differences in DNA-fingerprints from the varieties Atyrkuazh and Azhikvatsa only in one allele, respectively. When comparing the identified Abkhazian grape genotypes, their difference from the sample of Dagestan, Don, Greek, Turkish, Italian, Spanish, and French varieties and genetic similarity with the genotypes of Georgian grapes were shown.

Determining the pectinesterase enzyme activity when storing table grape varieties depending on the degree of ripening

Grapes are rich in easily digestible carbohydrates, mineral compounds, vitamins, phenolic compounds. and other vital components. It is known that fresh grapes can be used from September to December. To prolong the terms of consumption of this valuable raw material, the most appropriate varieties and conditions for storing grapes have been determined. White, pink, and red grape varieties were taken as the object of research. The changes in the activity of the pectinesterase enzyme were determined depending on the degree of ripening of table grape varieties, the change in the pectinesterase enzyme during storage of table grape varieties in various variants was investigated. Statistical processing and calculation of variations in the indicators of changes in the activity of the enzyme pectinesterase were performed, depending on the degree of ripening of grapes of the Shamakhi Marandi variety. During the study, the pectinesterase enzyme remained more stable in mature varieties. This means that in ripe table grape varieties, the absorption of nutrients in the respiratory process is significantly slowed down. However, as they mature, the activity of the pectinesterase enzyme gradually increases. Therefore, for long-term storage in refrigerated chambers, fully ripe varieties of table grapes were used; to this end, grapes of the white Ganja table variety, the pink Shamakhi Marandi variety, and the red Black Asma variety are more suitable. The comparison of the investigated variants showed that table grape varieties, when stored in a refrigerated chamber in a controlled atmosphere, at 3–4 % CO2 and 2–3 % O2, retain better quality than other variants. When storing table grape varieties of various variants in the refrigerator, the enzyme activity decreases but is not completely suppressed.

Establishment of foundation nurseries of new grape varieties using method of green grafting in the growing conditions of the Tersko-Kuma sands

Целью работы являлось создание первичных маточников интенсивного типа новых сортов винограда ускоренным методом. В работе представлены результаты закладки первичных маточников методом перепрививки корнесобственных насаждений сорта Цветочный в качестве подвоя на новые селекционные сорта столового назначения Илья, Памяти Смирнова, Барт, ИРС на песчаных землях ОАО «Винхоз «Бурунный», Чеченская республика. Зеленые прививки осуществлялись методом окулировки на зеленый побег с пробуждением глазка на высоте 20-25 см и 40-45 см над уровнем почвы, без пробуждения глазка - на высоте 20-25 см. По результатам данных за 2018 и 2019 гг. сделан вывод о перспективности создания маточников методом зеленой прививки окулировкой. Лучшие данные по приживаемости прививок и их развитию получены в варианте выполнения прививки методом окулировки на высоте 20-25 см с пробуждением глазка, приживаемость прививок в среднем по сортам составила от 74 до 94 %; в варианте с производством окулировки на высоте 40-45 см - 71-88,5%. Метод перепрививки кустов на высоте 20-25 см от поверхности почвы позволил на следующий после прививки год заготовить от 0,86 до 4,2 стандартных черенков нового сорта с одного куста. The aim of the work was to establish intensive type foundation nurseries of new grape varieties by an accelerated method. The paper presents the results of establishing foundation nurseries using sugreffage method of own-rooted plants of the ‘Tsvetochniy’ variety as a rootstock for new breeding table varieties ‘Ilya’, ‘Pamyati Smirnova’, ‘Bart’, ‘IRS’ on sandy lands of OJSC Vinkhoz Burunny of the Chechen Republic. Green grafting was carried out using method of oculation on green shoots with bud awakening at a height of 20-25 cm and 40-45 cm above the soil level, without bud awakening at a height of 20-25 cm. Based on the data results for 2018 and 2019, the prospects of establishing nurseries using method of green grafting were concluded. The best data on grafting survival ability and development was obtained in the variant of oculation with bud awakening at a height of 20-25 cm and ranged from 74% to 94%; in the variant with oculation at a height of 40-45 cm - 71% - 88.5%. The sugreffage method of bushes at a height of 20-25 cm above the soil level allowed harvesting the next year after grafting from 0.86 to 4.2 standard cuttings of new variety per one bush.