Rootstock Effects on Fruit Yield and Quality of 'BRS Tainá' Seedless Table Grape in Semi-Arid Tropical Conditions.

In viticulture, choosing the most suitable rootstock for a specific scion cultivar is an efficient and cost-effective way to increase yield and enhance the physicochemical characteristics of the fruit. The objective of this study was to evaluate the agronomic performance of the 'BRS Tainá' grapevine on different rootstocks under the conditions of the Sub-Middle São Francisco Valley. The main experimental factor consisted of eight rootstocks (IAC 313, IAC 572, IAC 766, 101-14 MgT, Paulsen 1103, Ramsey, SO4, and Teleki 5C), arranged in randomized blocks with four replicates. The experiment was conducted over four production cycles, from 2021 to 2023, in a commercial crop area in Petrolina, PE, Brazil. There were significant effects of rootstocks for the yield and number of bunches per plant, as well as berry length and firmness. 'BRS Tainá' achieved the highest yield (22.2 kg per plant) when grafted onto the Paulsen 1103 rootstock, which was superior to the yield on 101-14 MgT, IAC 313, and IAC 572 rootstocks. The highest number of bunches (88) was obtained with 'BRS Tainá' grafted on Paulsen 1103, while the lowest number (63) was obtained on IAC 572; both these rootstocks were not significantly different from the other rootstocks. For all scion-rootstock combinations, the mean values for soluble solid (SS) content, titratable acidity (TA), and the SS/TA ratio were similar to those previously described for 'BRS Tainá', meeting the commercialization standard. The results for the yield and number of bunches per plant indicate the suitability of grafting 'BRS Tainá' on Paulsen 1103 under the semi-arid tropical conditions of the São Francisco Valley.

White wine vinification and an expanded insight into pellicular macerations: bibliometric and bibliographic review.

BACKGROUND: Pellicular macerations in the vinification of white wines involve the contact of grape skins and seeds with the must before, during or after alcoholic fermentation. Pre-fermentative pellicular maceration aims to enrich the must with volatile compounds and aroma precursors. Fermentative maceration occurs during alcoholic fermentation, whereas post-fermentative maceration is carried out after this process, associated with orange, amber or skin-contact wines, which have experienced a growing global demand in recent years. In this context, this research aimed to conduct a bibliometric review on pellicular macerations in white wines using two search strategies on the specific platform for the period from 2010 to 2023. Additionally, we sought to identify research trends in this segment of the wine industry through a comprehensive literature review of the retrieved documents. RESULTS: The results emphasized more studies on pre-fermentative pellicular maceration than on long-duration macerations during and after alcoholic fermentation. Alternative maceration techniques, such as grape freezing, were also observed as study subjects, including their effects on final wines. The research identified a wide variety of grapes explored in studies related to pellicular macerations of the Vitis vinifera L. species, with approximately 50 distinct nomenclatures identified. Regarding pre-fermentative macerations, the contact time varied from 2 to 60 h, with the temperature range 1-20 °C. CONCLUSION: The specific search for extended skin contact white wines revealed a limited number of available documents, indicating that studies related to this product style are promising and necessary, given the growing commercial relevance of this product profile. © 2024 Society of Chemical Industry.

Phenolic composition and encapsulation of Brazilian grape seed extracts: evaluating color stabilizing capacity in grape juices.

The color of grape juice is an important acceptance attribute by consumers, but it suffers losses during storage. The use of commercial antioxidants has limitations because the concept of a "100% natural drink" of Brazilian legislation. This work characterized Brazilian grape seeds, and the cultivar extract with the greatest potential was encapsulated in arabic-gum (encapsulated extract-EE) to evaluate the color stabilizing capacity. The EE used in the grape juice was compared with the commercial antioxidants sulphite and enological tannin during storage (150 days). The BRS Magna and BRS Violeta grape seeds had the highest phenolic content, and the EE showed high catechin (4108 mg/kg), epicatechin (1161 mg/kg) and procyanidin-B2 (905 mg/kg) values. Sulfite was found to be the best color stabilizer. The use of EE (0.5 g/L) in grape juice improved color stability and anthocyanin stability. It was demonstrated that encapsulated grape seed extract has color stabilizing potential and that Brazilian grape seeds are a raw material of high technological value. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05956-8.

A Conservative Mutant Version of the Mrr1 Transcription Factor Correlates with Reduced Sensitivity to Fludioxonil in Botrytis cinerea.

Fludioxonil is a highly effective phenylpyrrole fungicide for controlling Botrytis cinerea. Although the field efficacy of fludioxonil remains high, Botrytis cinerea isolates with reduced sensitivity have been reported globally. The molecular target of fludioxonil still remains unknown; however, a mechanism of reduced sensitivity to fludioxonil underlies the overexpression of the ATP binding cassette (ABC) transporter AtrB in a dependent pathway of the Mrr1 transcription factor. Fludioxonil is a key player in controlling B. cinerea infection in table grapes in Chile. However, some isolates with a reduced sensitivity to fludioxonil were detected. This study observed endogenous atrB overexpression in Chilean isolates with reduced sensitivity to fludioxonil (n = 22) compared to the sensitive isolates (n = 10). All isolates increased the expression of atrB in a growth medium supplemented with fludioxonil (0.05 µg/mL). However, sensitive isolates showed lower atrB expression than those with reduced fludioxonil sensitivity. Remarkably, a mutant version of the transcription factor Mrr1 carrying 21 amino acid modifications was identified in all isolates with reduced sensitivity to fludioxonil. These changes alter the protein's transcription factor domain and the C-terminal portion of the protein but not the Zn (2)-C6 fungal-type DNA-binding domain. These results suggest a direct relationship between the conserved and divergent mutant version of mrr1 and sensitivity to fludioxonil. This study provides a new target for developing molecular diagnostic strategies to monitor B. cinerea's sensitivity to fludioxonil in the field.

Isolation and identification of native yeasts from the spontaneous fermentation of grape musts.

Recently, there has been growing interest in the characterization of native yeasts for their use in production of wines with regional characteristics. This study aimed to investigate Saccharomyces and non-Saccharomyces yeasts present in the spontaneous fermentation of Tannat and Marselan grape musts collected from Concordia (Entre Ríos, Argentina) over 2019, 2020, and 2021 vintages. The evolution of these fermentative processes was carried out by measuring total soluble solids, total acidity, volatile acidity, pH, ethanol concentration, and total carbon content. Isolated Saccharomyces and non-Saccharomyces yeasts were identified based on colony morphology in WL medium, 5.8S-ITS-RFLP analysis, and 26S rDNA D1/D2 gene sequencing. Two hundred and ten yeast colonies were isolated and identified as Pichia kudriavzevii, Saccharomyces cerevisiae, Hanseniaspora uvarum, Metschnikowia pulcherrima, Candida albicans, Candida parapsilosis, Pichia occidentalis, Pichia bruneiensis, Hanseniaspora opuntiae, Issatchenkia terricola, and Hanseniaspora vineae. P. kudriavzevii isolated from all vintages was associated with the spontaneous fermentation of grape musts from the Concordia region.

The Chemical, Microbiological and Volatile Composition of Kefir-like Beverages Produced from Red Table Grape Juice in Repeated 24-h Fed-Batch Subcultures.

The aim of this work was to study the production of kefir-like beverages via the fed-batch fermentation of red table grape juice at initial pHs of 3.99 (fermentation A) and 5.99 (fermentation B) with kefir grains during 4 repeated 24-h fed-batch subcultures. All kefir-like beverages (KLB) were characterized by low alcoholic grade (≤3.6%, v/v) and lactic and acetic acid concentrations. The beverages obtained from fermentation B had lower concentrations of sugars and higher microbial counts than the KLB obtained in fermentation A. Additionally, the KLB samples from fermentation B were the most aromatic and had the highest contents of alcohols, esters, aldehydes and organic acids, in contrast with the nonfermented juice and KLB from fermentation A. These results indicate the possibility of obtaining red table grape KLB with their own distinctive aromatic characteristics and high content in probiotic viable cells, contributing to the valorization of this fruit.

Prospection of indigenous yeasts from Uruguayan Tannat vineyards for oenological applications.

Prospection of yeasts from oenological environments can provide knowledge of new native strains that are capable of fermenting must and positively influence the composition and sensory characteristics of the wine. This work addressed the biotechnological characterization of indigenous yeasts of Tannat must, an emblematic and widespread vineyard of Uruguay. Fifty-three yeast isolates were morphologically characterized and further identified by amplification and sequencing of ITS and D1-D2 regions, grouping into a total of fifteen species. One isolate of each species was randomly chosen and evaluated for its technological traits. In presence of ethanol (6 to 16% v/v) and sulfur dioxide (40 mg/L), native Saccharomyces cerevisiae 3FS presented the best growth rates and minor lag phase. Regarding non-Saccharomyces strains, Starmerella bacillaris 3MS stood out for its behavior in vinification conditions, more closely related to S. cerevisiae strains. Saccharomyces cerevisiae 3FS, Starmerella bacillaris 3MS, and Saturnispora diversa 1FS conducted a successful fermentation process reaching a final ethanol concentration ≥ 10% v/v and presenting a killer and resistant phenotype, suggesting that they could be used as pure starter cultures, as well as in mixed culture fermentations. This preliminary screening and oenological characterization of indigenous Saccharomyces cerevisiae and non-Saccharomyces yeasts might be a useful tool to identify some strains as potential candidates for wine vinification.

Maturation and quality of 'BRS Magna' grapes influenced by rootstocks in rainy season

Seasonal variations and production factors can influence the quality of grapes. Considering the Sub-middle region of the São Francisco Valley, Brazil, differentiated by production in rainy and warmer periods of the year, the climatic conditions in each season affect the duration of the phenological phases and quality of the grapes. The objective of this study was to characterize the changes in the quality components during maturation of 'BRS Magna' grapes on different rootstocks, in rainy seasons under tropical conditions, as a support to define the harvest time. The experiment was conducted in Petrolina, Pernambuco, Brazil, from Jan to Apr 2017 (cycle 1) and Dec 2017 to Apr 2018 (cycle 2) evaluating rootstocks and age of the fruits. Bunches were picked from the start of maturation to the harvest: 49, 56, 61, 64 and 68 days after fruit set (DAF) for cycle 1, and 35, 41, 48, 55, 61, and 66 DAF for cycle 2. In cycle 1 'IAC 572' and 'Paulsen 1103' rootstocks provided higher sugar contents in grapes, which was only repeated in cycle 2 for 'Paulsen 1103'. The accumulation of anthocyanins and yellow flavonoids was favored by 'IAC 313' and 'IAC 572' rootstocks in cycle 1, and by 'IAC 313' and 'IAC 766' in cycle 2. A higher content of polyphenols was conferred on 'IAC 572' in cycle 1 and on 'IAC 766' in cycle 2, which also had a greater antioxidant capacity. Although there were differences between rootstocks, harvesting at approximately 64 DAF maximized grape quality for all treatments.(AU)

Volatile Organic Compounds (VOCs) Produced by Gluconobacter cerinus and Hanseniaspora osmophila Displaying Control Effect against Table Grape-Rot Pathogens.

Table grapes (Vitis vinifera) are affected by botrytis bunch rot and summer bunch rot, the latter a complex disease caused by Botrytis cinerea, Aspergillus spp., Penicillium expansum and Rhizopus stolonifer. To search for biocontrol alternatives, a new bioproduct composed of Gluconobacter cerinus and Hanseniaspora osmophila, a consortium called PUCV-VBL, was developed for the control of fungal rots in table grapes. Since this consortium presents new biocontrol species, the effect of their VOCs (volatile organic compounds) was evaluated under in vitro and in vivo conditions. The VOCs produced by the PUCV-VBL consortium showed the highest mycelial inhibition against Botrytis cinerea (86%). Furthermore, H. osmophila was able to inhibit sporulation of A. tubingensis and P. expansum. VOCs' effect in vivo was evaluated using berries from Red Globe, Thompson Seedless and Crimson Seedless grapes cultivars, demonstrating a mycelial inhibition by VOCs greater than 70% for all evaluated fungal species. The VOC identification of the PUCV-VBL consortium was analyzed by solid-phase microextraction coupled to gas chromatography-mass spectrometry (SPME-GCMS). A total 26 compounds were identified, including 1-butanol 3-methyl, propanoic acid ethyl ester, ethyl acetate, phenylethyl alcohol, isobutyl acetate and hexanoic acid ethyl ester. Our results show that VOCs are an important mode of action of the PUCV-VBL biological consortium.

Biology and Population Dynamics of the American Vine Moth and the Potential Biocontrol with Trichogramma pretiosum.

The American grapevine moth (AGVM), Lasiothyris luminosa (Razowski & Becker) (Lepidoptera: Tortricidae), was recently registered as a new pest for table grapes in the Northeast region of Brazil. In the present study, two approaches were made aiming to aid information to support management strategies for the new pest control: (i) study AGVM biology in the laboratory and its population dynamics in the field and (ii) evaluate Trichogramma pretiosum Riley as a potential biological control method against L. luminosa. The AGVM population dynamics showed a similar trend in the three grapevine monitored vineyards. The larvae started occurring at 30 days after pruning (DAP), pre-bloom stage, with a peak population between 54 and 78 DAP, following a decrease until harvest. The AGVM females larva, pupa, and egg-adult period were longer than males. The egg-adult period was 42.1 and 45.2 days for male and females, respectively. Trichogramma pretiosum was able to parasitize L. luminosa eggs. The T. pretiosum egg-adult period was 10.2 days with a 98.5% pupa survivorship at 25 °C. The release of T. pretiosum in the vineyards resulted in 65.5 to 73.2% AGVM egg parasitism. Our findings bring the first biological and population dynamics information for L. luminosa, which can help developing efficient approaches to monitor and control the pest in grapevines. The release of T. pretiosum in the vineyard is a potential biological control option to AGVM.

Role of partial dehydration in a naturally ventilated room on the mycobiota, ochratoxins, volatile profile and phenolic composition of Merlot grapes intended for wine production.

Dehydration of grapes has been used in various regions of the world to produce special wines, aiming to add value to oenological products. Post-harvest dehydration in rooms may be carried out regardless of weather conditions, without the additional cost of a specific infrastructure, in addition to the benefits of protecting the grapes from damages and environmental pollution. The objective of this study was to verify, for the first time, the impact of the dehydration in a naturally ventilated room on the quality of Merlot grapes. Physicochemical characteristics, mycobiota, occurrence of mycotoxins, volatile profile and phenolic composition of grapes were monitored on 7th, 14th and 21st days of dehydration (weight loss of 10, 20 and 27%, respectively). A decrease in aw (6%), pH (4%), and berry hardness (58%), along with an increase in total soluble solid content (15%) were observed during dehydration. The presence of Pestalotiopsis clavispora, Neopestalotiopsis clavispora, Colletotrichum siamense and Alternaria porri was favored during the dehydration process, while a decrease in the occurrence of Aspergillus niger and Phanerochaete sp. was verified. A. niger isolates showed no potential to produce forms of ochratoxins. These toxins were also not found in the grape samples. Regarding the volatile profile, 1-hexanal, 2-hexenal, and 1-octanal gave rise to the corresponding alcohols during dehydration, such as 1-hexanol, 2-hexen-1-ol, and 1-octanol. Acids (hexanoic, decanoic, and 3-hexenoic) resulted in the respective ethyl esters (hexanoate, decanoate, and ethyl 3-hexenoate) during dehydration. Terpenes as limonene, myrcene, and geraniol decreased throughout dehydration, while their biotransformation products (α-terpineol, 6-methyl-5-hepten-2-one, and linalool, respectively) had an increase in concentration. The phenolic content oscillated during dehydration, with an emphasis on increased levels of four hydroxybenzoic acids (ethyl gallate, p-hydroxybenzoic acid, gallic acid-hexose, and gallic acid), two hydroxycinnamic acids (caffeic acid and caftaric acid), two flavonols (kaempeferol galactoside and quercetin) and two anthocyanins (peonidin 3-O-hexoside and delphinidin 3-O-hexoside). Grapes of satisfactory quality were produced by dehydration in a naturally ventilated room. Even small wine producers can be encouraged to implement this procedure for the diversification of oenological products, as it has no costs related to the implementation of chambers/tunnels.

Anti-oxidant and anti-inflammatory effect of polar extracts obtained from waste product of wine making.

A lot of diseases are characterized by an increased inflammatory response with an exacerbated production of free radicals. The anti-inflammatory effect of different compounds with antioxidant capacity, as polyphenols present in grape is well known. Therefore, the objective is to evaluate the anti-oxidant and anti-inflammatory activity of waste product of wine production.Six different non-toxic-marc-polar extracts from Malbec and Syrah grape varieties were obtained, their total phenol and flavonoid content were evaluated, and their antioxidant and anti-inflammatory activity were determined.High content of total phenols and flavonoids were found mainly in extracts obtained from Syrah (80.51 ± 16.63 g equivalent to gallic acid/100 g and 25.47 ± 3.33 g equivalent to quercetin/100 g). In addition, they had a high antioxidant effect (above 88.5% of ABTS inhibition by Syrah extracts). Finally, all extracts decreased the nitric oxide (NO) production, but this was more accented when extract from Syrah obtained by infusion was used, which decreased NO levels to baseline (4.46 µM).Taking together, our results show the potential pharmaceutical use of waste product of wine making to prevent or to treat diseases which inflammatory response is exacerbated.

First report of injuries associated with triclopyr herbicide drift in grapevines / Primeiro relato de danos associados à deriva do herbicida triclopir em videiras

In the southern region of Brazil, close proximity of vineyards to soybean areas is common, and glyphosate is used frequently to allow for the control of weeds. However, the continuous use of this chemical has accelerated the process of selection for resistant species such as horseweed (Conyza spp.), thus leading to the search for alternative herbicides such as triclopyr to control this weed. To the best of our knowledge, this is the first report detailing injuries associated with triclopyr drift in grapevines in Brazil, in the Northern region of Parana state, that can result in crop losses that were previously uncharacterized. In this report, the primary symptoms associated with the drift of triclopyr in grapevines are described. Additionally, the major implications of this process regarding vine development along the next crop seasons are explored, and the primary measures to prevent these injuries are discussed.(AU)

Na região sul do Brasil é comum a proximidade de parreirais às lavouras de soja, sendo que no controle de plantas daninhas é frequentemente utilizado o herbicida glifosato. Porém, o seu uso acelerou o processo de seleção de espécies resistentes, como a buva (Conyza spp.), levando à procura por herbicidas alternativos, como o triclopir para o controle dessa planta daninha. Nesse trabalho é feito o primeiro relato de danos associados à deriva da aplicação de triclopir em áreas de produção de uvas no Brasil na região Noroeste do Estado do Paraná, causando prejuízos à cultura até então desconhecidos. Nessa comunicação, os principais sintomas associados à deriva desse herbicida em videiras são descritos, bem como discutidas as suas principais implicações no desenvolvimento das videiras nos próximos ciclos produtivos, e as medidas para que os danos sejam evitados.(AU)

Bioactive Compounds and Metabolites from Grapes and Red Wine in Breast Cancer Chemoprevention and Therapy.

Phytochemicals and their metabolites are not considered essential nutrients in humans, although an increasing number of well-conducted studies are linking their higher intake with a lower incidence of non-communicable diseases, including cancer. This review summarizes the current findings concerning the molecular mechanisms of bioactive compounds from grapes and red wine and their metabolites on breast cancer-the most commonly occurring cancer in women-chemoprevention and treatment. Flavonoid compounds like flavonols, monomeric catechins, proanthocyanidins, anthocyanins, anthocyanidins and non-flavonoid phenolic compounds, such as resveratrol, as well as their metabolites, are discussed with respect to structure and metabolism/bioavailability. In addition, a broad discussion regarding in vitro, in vivo and clinical trials about the chemoprevention and therapy using these molecules is presented.

Analysis of the phenolic composition and yield of 'BRS Vitoria' seedless table grape under different bunch densities using HPLC-DAD-ESI-MS/MS.

Grapes are considered to be a major source of phenolic compounds as compared with other fruits. To improve the quality of table grapes, some techniques like thinning can be used. In addition, grape cultivars with distinct characteristics are directly linked to its phenolic profile. This study aimed to identify and quantify the phenolic compound profile and yield of the hybrid 'BRS Vitoria' seedless table grape under different bunch densities, using a combination of solid-phase extraction (SPE) methodologies and analytical high-performance liquid chromatography-diode array detector with tandem mass spectrometry (HPLC-DAD-ESI-MS/MS). A trial was carried out in 2016, in a commercial vineyard at Marialva, state of Parana (South Brazil). Three weeks after anthesis, the following bunch densities were evaluated: 4.0, 4.5, 5.0, 5.5, and 6 bunches per m2 (corresponding to an estimation of 16, 18, 20, 22, and 24 tons ha-1). The randomized block design was used as a statistical model with each treatment was replicated four times, with one vine per plot. Different characteristics were evaluated at harvest, e.g., soluble solids content (SS), total acidity (TA), maturation index (MI = SS/TA), bunch and berry masses, yield, as well hydroxycinnamic acid derivative (HCAD), anthocyanin, flavonol, and flavan-3-ol contents by HPLC-DAD-ESI-MS/MS analysis. The evaluated bunch densities did not interfere with the physicochemical characteristics of the berries, such as SS and MI. Under the density of 6.0 bunches per m2, the highest yield of 25 tons ha-1 was reached. Under all bunch densities, the phenolic profile presented the same compounds, but at different concentrations. Under a density of 5.0 bunches per m2, the compounds belonging to the anthocyanin and flavonol families were present in high concentrations. In contrast, at the densities of 4.0 and 4.5 bunches per m2, there was a reduction in the flavan-3-ol content. With respect to stilbenes, only the trans-piceid and its cis- isomer were detected. However, their concentrations had no significant influence on the evaluated bunch densities.

Grape seed proanthocyanidins prevent H2 O2 -induced mitochondrial dysfunction and apoptosis via SIRT 1 activation in embryonic kidney cells.

Grape proanthocyanidins are compounds widely ingested in the diet. This study evaluated their effects on mitochondrial function, apoptosis, and sirtuin 1 and 3 expressions in HEK-293 cells exposed to H2 O2 . High-resolution mass spectrometry and high-performance liquid chromatography characterized the proanthocyanidins extract and the presence of procyanidins B and C was detected. The extract prevented H2 O2 -induced oxidative damage to proteins and lipids and depletion in superoxide dismutase activity. Moreover, it was able to regulate the expression of NADH: Ubiquinone oxidoreductase core subunit S7 and prevent mitochondrial electron transport chain dysfunction, ATP depletion, and apoptosis induced by H2 O2 . Finally, the extract was able to regulate sirtuin 1 and 3 expressions, thus maintaining cell viability. These data show that the grape seed proanthocyanidins can target mitochondrial proteins, which may represent an important approach for the management of numerous chronic illnesses associated with mitochondrial dysfunction. PRACTICAL APPLICATIONS: Proanthocyanidins are phenolic compounds abundant in regular diet, commonly found in grapes and derivatives, pomegranates, apples, and red fruits, all foods known for their beneficial effects on health. The current study highlights the role of proanthocyanidins as mitochondrial modulators that may explain the biological activity attributed to these compounds. This study brings evidence that proanthocyanidins might be considered as a value-added agent for the development of new nutraceutical and or pharmaceutical approaches.

Effects of Interspecific Larval Competition on Developmental Parameters in Nutrient Sources Between Drosophila suzukii (Diptera: Drosophilidae) and Zaprionus indianus.

Two invasive drosophilids, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) and Zaprionus indianus (Gupta) (Diptera: Drosophilidae) are expanding their geographic distribution and cohabiting grape production in the Mid-Atlantic. The ecological and economic impact of these two species within vineyards is currently unknown. Zaprionus indianus was presumably not capable of ovipositing directly into grapes because they lack a serrated ovipositor and may use D. suzukii oviposition punctures for depositing their own eggs. Therefore, an interspecific larval competition assay was performed at varying larval densities using commercial medium and four commonly grown wine grapes in Virginia to investigate the impact Z. indianus larvae may have on the mortality and developmental parameters of D. suzukii larvae. Zaprionus indianus did not affect D. suzukii mortality or development parameters even at high interspecific densities when reared in commercial medium, but it did cause higher D. suzukii mortality within grapes. Mortality was also influenced by the variety of grape in which the larvae were reared, with smaller grapes having the highest D. suzukii mortality. Presence of Z. indianus also increased development time to pupariation and adult emergence for most interspecific competition levels compared with the intraspecific D. suzukii controls. Pupal volume was marginally affected at the highest interspecific larval densities. This laboratory study suggests that competition from Z. indianus and grape variety can limit D. suzukii numbers, and the implications on D. suzukii pest management be further verified in the field.

Control of Gray Mold on Clamshell-Packaged 'Benitaka' Table Grapes Using Sulphur Dioxide Pads and Perforated Liners.

The use of vented clamshells has become popular in the packaging of grapes for local and international markets. The aim of this study is to evaluate the postharvest preservation of 'Benitaka' table grapes individually packaged in vented clamshells using different types of SO2-generating pads and perforated plastic liners during cold storage. A completely randomized design with four replications in a two-factor arrangement with an additional treatment [(4 × 3) + 1] was used. The trials were carried out under two situations: Artificial or natural infections with Botrytis cinerea, which is the causal agent of gray mold on table grapes. The incidence of gray mold, shattered berries, and stem browning were evaluated at 30 and 45 days of cold storage at 1 ± 1 °C and 3 days of shelf-life at 22 ± 1 °C after the period of cold storage. Mass loss and berry firmness were also examined at the end of the cold storage period. The use of dual-release SO2-generating pads containing 5 or 8 g of a.i. and slow-release pads with 7 g of a.i. was effective in controlling the incidence of gray mold in grapes packaged in vented clamshells and kept under cold storage for up to 45 days. Under these storage conditions, perforated plastic liners with 0.3% ventilation area or micro-perforated liners with 1.0% ventilation area reduced the percentage of mass loss and shattered berries.

Yeast diversity in Vitis non-vinifera ecosystems / Diversidad de levaduras en ecosistemas de Vitis no-vinifera

The surface of grapes lodges a complex community of yeast species responsible for spontaneous alcoholic fermentation. The study of indigenous Saccharomyces and "non-Saccharomyces" yeasts during grape must fermentation constitutes a major research area in microbial enology. Although there are detailed studies on the microbiota of Vitis vinifera grapes, little is known about the diversity of yeast communities present in non-vinifera Vitis ecosystems (i.e., grapes and spontaneously fermenting grape musts). Potentially scientific and/or enological valuable yeast strains from these non-vinifera Vitis ecosystems might never be isolated from V. vinifera L. In this updated review, we summarize relevant aspects of the microbial studies conducted on V. non-vinifera grapes and spontaneously fermenting grape musts.

La superficie de las uvas aloja una comunidad compleja de especies de levaduras responsables de la fermentación alcohólica espontánea. El estudio de estas levaduras Saccharomyces y «no-Saccharomyces¼ durante la fermentación del mosto de uvas constituye un área relevante de investigación microbiológica en enología. Si bien existen estudios detallados de la microbiota de uvas de Vitis vinifera L., poco se sabe sobre la diversidad de comunidades de levaduras presentes en ecosistemas de Vitis no-vinifera (i.e., uvas y mostos en fermentación espontánea). Cepas de levaduras presentes en ecosistemas de Vitis no-vinífera, con valor potencial científico y/o enológico, podrían no estar presentes en V. vinifera L. En esta revisión actualizada, resumimos los aspectos relevantes de los estudios microbiológicos efectuados en mostos en fermentación espontánea de uvas de V. no-vinifera.

Effects of successive harvesting in the same year on quality and bioactive compounds of grapes and juices in semi-arid tropical viticulture.

The technological and polyphenolic parameters of grapes for juice processing obtained from successive harvests were studied in semi-arid tropical viticulture. Red grapes "BRS Violeta" and "Isabel Precoce" were harvested during the same year and analyzed based on a multivariate approach that included climatic variations. The grapes were marked by variations in flavonoid compounds, particularly anthocyanins. Temperature, global radiation, air velocity and evapotranspiration rates were associated with higher accumulation of bioactive polyphenols in grape berries and juices. The temperatures in February were associated with higher antioxidant activity in grape peels, while the highest thermal amplitude in August and November favored the accumulation of anthocyanins up to 564 mg kg-1. Flavanols and procyanidin compounds were more abundant in seeds when the maximum thermal amplitude was 13.8 °C. The climatic data together with the polyphenolic results point out useful information about appropriate periods for harvesting grapes with high phenolic content in tropical areas.