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Grapes represent a significant source of phenolic compounds known for their health-promoting properties, such as antioxidant capacity on normal cells and prooxidant activity on tumor cells. The genotype highly affects the polyphenolic composition in grapes and, consequently, the nutritional quality of berries. This work aimed to characterize the phenolic composition, the antioxidant, and anticancer activity of grape skin extracts (GSEs) of nine new table grape genotypes selected from a breeding program to obtain new cultivars of seedless table grapes, well adapted to the climatic change and with higher nutraceutical properties. The grape polyphenolic profile was characterized by Ultra-High-Performance Liquid Chromatography/Quadrupole-Time of Flight mass spectrometry analysis. GSE antioxidant activity was determined by the ABTS, DPPH, and ORAC assays; GSE cell growth inhibition test was carried out in the Caco2 human cancer cell line. The nine GSEs showed different flavonoid and non-flavonoid profiles, and all possessed antioxidant activity, with the ‘Aika N.’, ‘Turese N.’, and ‘Egnatia N.’ the most active. As anticancer activity against the tested cancer cell line, ‘Daunia N.’ and ‘Apenestae N.’ showed the EC50 after 24 h of 35.60 µg/mL and 150.91 µg/mL, respectively. The relationship between polyphenolic profile and the antioxidant and anticancer activity of GSE was also investigated. Interestingly, among the different classes of polyphenolics, flavan-3-ols e proanthocyanidins showed the highest positive correlation with the anticancer activity of extracts. These findings can be helpful for the preparation of new extracts for the pharmaceutical and nutraceutical industry and geneticists working in vine breeding programs.

In this article, a combination of non-destructive NIR spectroscopy and machine learning techniques was applied to predict the texture parameters and the total soluble solids content (TSS) in intact berries. The multivariate models obtained by building artificial neural networks (ANNs) and applying partial least squares (PLS) regressions showed a better prediction ability after the elimination of uninformative spectral ranges. A very good prediction was obtained for TSS and springiness (R2 0.82 and 0.72). Qualitative models were obtained for hardness and chewiness (R2 0.50 and 0.53). No satisfactory calibration model could be established between the NIR spectra and cohesiveness. Textural parameters of grape are strictly related to the berry size. Before any grape textural measurement, a time-consuming berry-sorting step is compulsory. This is the first time a complete textural analysis of intact grape berries has been performed by NIR spectroscopy without any a priori knowledge of the berry density class.

Mixed fermentation using Starmerella bacillaris and Saccharomyces cerevisiae has gained attention in recent years due to their ability to modulate the qualitative parameters of enological interest, such as the color intensity and stability of wine. In this study, three of the most important red Apulian varieties were fermented through two pure inoculations of Saccharomyces cerevisiae strains or the sequential inoculation of Saccharomyces cerevisiae after 48 h from Starmerella bacillaris. The evolution of anthocyanin profiles and chromatic characteristics were determined in the produced wines at draining off and after 18 months of bottle aging in order to assess the impact of the different fermentation protocols on the potential color stabilization and shelf-life. The chemical composition analysis showed titratable acidity and ethanol content exhibiting marked differences among wines after fermentation and aging. The 48 h inoculation delay produced wines with higher values of color intensity and color stability. This was ascribed to the increased presence of compounds, such as stable A-type vitisins and reddish/violet ethylidene-bridge flavonol-anthocyanin adducts, in the mixed fermentation. Our results proved that the sequential fermentation of Starmerella bacillaris and Saccharomyces cerevisiae could enhance the chromatic profile as well as the stability of the red wines, thus improving their organoleptic quality.

Postharvest spoilage fungi, such as Botrytis cinerea, are considered the main cause of losses of fresh fruit quality and vegetables during storage, distribution, and consumption. The current control strategy is the use of SO2 generator pads whose application is now largely under observation. A high quantity of SO2 can be deleterious for fresh fruits and vegetables and it is not allowed in organic agriculture. For this reason, great attention has been recently focused on identifying Biological Control Agents (BCA) to implement biological approaches devoid of chemicals. In this direction, we carried out our study in isolating five different non-Saccharomyces yeast strains from local vineyards in the South of Italy as possible BCA. We performed both in vitro and in vivo assays in semi-commercial conditions on detached grape berries stored at 0 °C, simulating the temperature normally used during cold storage, and obtained relevant results. We isolated three M. pulcherrima strains and one L. thermotolerans strain able to largely antagonize the development of the B. cinerea, at both in vitro and in vivo conditions. In particular, we detected the ability of the three isolates of M. pulcherrima strains Ale4, N20/006, and Pr7 and the L. thermotolerans strain N10 to completely inhibit (100% in reduction) the mycelial growth of B. cinerea by producing fungistatic compounds. We found, using an extracellular lytic enzymes activity assay, that such activity could be related to lipid hydrolyzation, β-1,3-glucanase and pectinase activity, and pectinase and protease activity, depending on the yeasts used. Results from our in vitro assays allowed us to hypothesize for M. pulcherrima strains Ale4 and N20/006 a possible combination of both the production of soluble metabolites and volatile organic compounds to antagonize against B. cinerea growth. Moreover, in semi-commercial conditions, the M. pulcherrima strain N20/006 and L. thermotolerans strain N10 showed relevant antagonistic effect also at low concentrations (with a significantly reduction of ‘slip skin’ incidence of 86.4% and 72.7%, respectively), thus highlighting a peculiar property to use in commercial development for organic agriculture and the handling process.

Texture characteristics are valuable parameters in the perceived quality and overall acceptability of fresh fruit. The characterization of grape texture attributes, such as firmness and crunchiness, is usually performed by sensory analysis or instrumental texture analysis. Both methodologies are destructive. Hence, it is not possible to test multiple times or perform any other analysis on the same sample. In this article, near-infrared (NIR) spectroscopy was applied to intact berries of table grape cv. Regal Seedless. NIR spectra were employed to predict both the physical parameter “hardness”, which is correlated with the crunchiness of berry flesh and the sweetness, which is correlated with the total soluble solids content (TSS, as °Brix). The chemometric analysis was carried out exclusively based on an open-source software environment, producing results readily usable for any operator, besides the specific level of experience with NIR spectroscopy.

Seedless inheritance has been considered a quasi-monogenic trait based on the VvAGL11 gene. An intragenic simple sequence repeat (SSR) marker, p3_VvAGL11, is currently used to opportunely discard seeded progeny, which represents up to 50% of seedlings to be established in the field. However, the rate of false positives remains significant, and this lack of accuracy might be due to a more complex genetic architecture, some intrinsic flaws of p3_VvAGL11, or potential recombination events between p3_VvAGL11 and the causal SNP located in the coding region. The purpose of this study was to update the genetic architecture of this trait in order to better understand its implications in breeding strategies. A total of 573 F1 individuals that segregate for seedlessness were genotyped with a 20K SNP chip and characterized phenotypically during four seasons for a fine QTL mapping analysis. Based on the molecular diversity of p3_VvAGL11 alleles, we redesigned this marker, and based on the causal SNP, we developed a qPCR-HRM marker for high-throughput and a Tetra-ARMS-PCR for simple predictive analyses. Up to 10 new QTLs were identified that describe the complex nature of seedlessness, corresponding to small but stable effects. The positive predictive value, based on VvAGL11 alone (0.647), was improved up to 0.814 when adding three small-effect QTLs in a multi-QTL additive model as a proof of concept. The new SSR, 5U_VviAGL11, is more informative and robust, and easier to analyze. However, we demonstrated that the association can be lost by intragenic recombination and that the e7_VviAGL11 SNP-based marker is thus more reliable and decreases the occurrence of false positives. This study highlights the bases of prediction failure based solely on a major gene and a reduced set of candidate genes, in addition to opportunities for molecular breeding following further and larger validation studies.

Fourier-transform near infrared spectroscopy (FT-NIR) is a technique used in the compositional and sensory analysis of foodstuffs. In this work, we have measured the main maturity parameters for grape (sugars and acids) using hundreds of intact berry samples to build models for the prediction of these parameters from berries of two very different varieties: “Victoria” and “Autumn Royal”. Together with the chemical composition in terms of sugar and acidic content, we have carried out a sensory analysis on single berries. Employing the models built for sugars and acids it was possible to learn the sweetness and acidity of each berry before the destructive sensory analysis. The direct correlation of sensory data with FT-NIR spectra is difficult; therefore, spectral data were exported from the spectrometer built-in software and analyzed with R software using a statistical analysis technique (Spearman correlation) which allowed the correlation of berry appreciation data with specific wavelengths that were then related to sugar and acidic content. In this article, we show how it is possible to carry out the analysis of single berries to obtain data on chemical composition parameters and consumer appreciation with a fast, simple, and non-destructive technique with a clear advantage for producers and consumers.

In recent years the wine sector has been characterized by an increased focus on the diversification of wine products. This change has been welcomed by consumers. In fact, today's consumers are willing to experiment with new products and unusual combinationswhich has stimulated research aimed at the discovery of native grape varieties suitable for for winemaking. In this context, particular attention are receiving vines for the production of dessert wines. Many regions have made efforts in the search for varieties and techniques able to better promote the drying process. At CREA-VE Turi-BA, there is an ongoing recovery and exploitation of indigenous grape varieties in the regions of Southern Italy and today more than 3,000 accessions of wine grapes are preserved. In the present work we have investigate the possibility of the use of certain accessions of Vitis vinifera varieties (collection CREA-VE Turi-BA) deemed attractive for the production of dessert wines. Accessions presenting a good sugar content and a good titratable acidity were selected; namely, Greco bianco b. (named Q19) and Mantonico bianco b. (named R8) were compared to the cv of Malvasia di Lipari b. Ampelographic and ampelometric analyses, followed by molecular analysis, were carried out for varietal assessment. A rate of the grapes were fermented immediately after harvest with standard procedure, in comparison to rates vinified after withering. The latter was made in a greenhouse type structure with parts of natural and unforced air, without any additional energy expense. At the end of the process, a loss in weight of the grapes equal to 30–35% was realized. The grapes are then stemmed, crushed, pressed and fermented by selected yeast under controlled temperature. Upon completion of the fermentation and subsequent stabilization, the wines were analyzed for the most important enological parameters and subjected to evaluation by a panel of expert tasters. Chemical analysis of wines showed that an alcohol content ranging to 11–12% volume was reached with in the standard wine-making; whilst, for the vinification of dried grapes the alcohol content was equal to 16% vol for Mantonico bianco b. and 18% vol. for and Greco bianco. Organoleptic analysis of the wines showed a greater appreciation for both of dessert wines. The best ratings were given for the olfactory characteristics (floral and fruity aromas) and taste characteristics. In particular, the Greco bianco b. had excellent scores slightly lower than Malvasia di Lipari b. Therefore, the tested varieties have shown a good potential for the production of dessert wines related to typicality of the grape and the region. Dessert wines produced, have a complex flavor profile and interesting for the high acidic component, which improved the taste perception of wine and attenuated the sensation of sweetness. That feature could allow a good wine aging, too.

Monomeric and polymeric flavan-3-ols (proanthocyanidins) content in grapes is higher in seeds compared to berry skins. Monomeric flavan-3-ols are more astringent, however, they can combine with other monomer, with anthocyanins and with mannoproteins released by yeast and therefore lose their harsh features in wines. Proanthocyanidins extracted during fermentation and maceration processes in red wines, are important for the organoleptic characteristics of the product and for its aging. There is a difference between skins and seeds proanthocyanidins, with the latter being perceived as more harsh and astringent. One of the most important purposes of refinement and aging of red wines very rich in polyphenols is the slow loss of bitterness. Instead, for wines ready to drink seeds tannins can give bitter overtones, therefore reducing their quality since consumers generally prefer a reduced astringency and attenuated bitterness. This paper investigates the possibility of employ some new seedless grapes crossings of Vitis vinifera L., obtained in recent breeding programs carried out at the CREA-VE of Turi, for the production of improved red and rosé wines made with traditionally red winemaking.

According to the CODEX STAN 255 (2007), table grapes can be harvested when the refractometric index reaches at least 16° Brix. Grapes with a lower refractometric index are accepted provided the sugar/acid ratio (Total Soluble Solids/Tritatable Acidity – TSS/TA) is at least equal to 20:1 if the Brix level is comprised between 12.5° and 14° Brix, 18:1 if the Brix level is comprised between 14° and 16° Brix. Some table grapes grown in Mediterranean climate can accumulate TSS higher than 16° Brix, with low levels of acidity, thus leading to a TSS/AT ratio even greater than 30: 1. Grapes that accumulate TSS less than 12.5° Brix and low TA levels, hardly reach the recommended ratio TSS/TA of 20:1, rather stopping at lower values. Based on these considerations in 2012 an experimental trial of four years started on a total of 103 table grape cvs. Phenological phases in relation to the acidic and sugar content were measured in order to assess the TSS/TA ratio and build regression lines with TSS. Almost all cvs. showed a significant linear regression, with R2 values higher than 0.80 and a standard error between 00.18 and 1.74. TSS values of 103 cvs. at TSS/TA ratio of 20:1, predicted by means of linear regression equations, , were subjected to cluster analysis based on Euclidean Distance. We identified nine clusters, of which the first two with the predicted TSS between 10.04° and 11.77° Brix (7 cvs.) and 12.08° and 12.62° Brix (7 cvs.), respectively. Some of the cvs. showing TSS values below 12.5° Brix at the TSS/TA of 20: 1, were subjected to a test panel of 24 tasters, who were asked to indicate the acceptability of these grapes on hedonic scale of 9 points. Preliminary results showed that for some table grapes with TSS below 12.5° Brix, a SST/AT ratio lower than the recommended 20:1 can be proposed, while preserving an acceptability by the consumer. These results suggest a more modern perspective on grapes nutritional intake, which takes into account the real needs of Western countries where diabetes, hyperglycemia, obesity and cardiovascular diseases are the main dismetabolisms arising from a diet too rich in calories. These grapes thus represent a new frontier and an opportunity for producers of table grapes, who want to enterprise a market share on “grape diet”, and represent a genetic basis for breeding aimed at obtaining new hypocaloric grape cultivars.

Although the high susceptibility of Vitis vinifera to the fungus Plasmopara viticola, several elements in this field suggest a variety-specific response to this oomycete infection. To date, not much is known about the degree of susceptibility to downy mildew segregates in populations derived from breeding of V. vinifera varieties with different degrees of susceptibility. Thus, CREA-Viticulture and Enology of Turi (BA) breeding program, among its goals, focuses on the identification of new Vitis genotypes showing more tolerance to this biotic stress. Starting from 2021, different genotypes belonging to two segregating populations, Inzolia imperiale x Autumn royal seedless and N22/050 ('Red globe' x 'Regal seedless') x 'Melissa', have been phenotypically evaluated for their differential response to P. viticola infection. In detail, a leaf disc assay was performed, and each leaf disc has been inoculated with 50 µL of a suspension of P. viticola zoosporangia. Five days after the inoculation the incidence of the disease was calculated as a percentage ratio between the number of leaf discs showing symptoms and the total number of tested discs. Furthermore, the severity of the infection was evaluated by using an empirical 0-to-4 rating scale and for each genotype the Mckinney's index was calculated. Noteworthy, data show that at least 10% of the tested genotypes, for each segregating population, are highly tolerant to the fungus infection. Among the Inzolia imperiale x Autumn royal seedless tested individuals, 18 out of 113 genotypes showing different responses to the infection were selected and the leaf disc assay was repeated on them to confirm their degree of tolerance/susceptibility to the disease. Moreover, to further investigate the genotypes response, some infected leaf discs from each genotype were collected and frozen in liquid nitrogen at different time points after inoculation and stored for transcriptomics studies aiming to evaluate differences in genes expression with respect to the degree of tolerance registered for each sample. The tolerance to the P. viticola infection of these genotypes will be tested also in the field in the next future and other commercial characteristic will be evaluated. We believe this work will lay the ground for providing in the next future new cultivars of V. vinifera, whose management will allow a lower environmental impact. [ABSTRACT FROM AUTHOR]