Mixed fermentation with Metschnikowia pulcherrima using different grape varieties

The study and use of non-Saccharomyces yeasts to wine improvement and diversification has gained considerable relevance in recent years. The present work reports a pilot-scale winery assay of mixed fermentation with a commercial strain of Metschnikowia pulcherrima, tested in five white and nine red grape varieties. Two modalities were assayed, one with the addition of M. pulcherrima at time zero and addition of Saccharomyces cerevisiae after 24 h, and a control using only S. cerevisiae at time zero. Fermentation was monitored by daily measurement of density and temperature. Wine physicochemical analysis was performed after winemaking and repeated after four years of aging. Variance and multivariate analysis were used to examine these data. Triangle and ranking tests were performed on the wines obtained, using an experienced sensory panel. Alcoholic fermentation proceeded smoothly until there was complete consumption of the sugars. M. pulcherrima in mixed fermentation, although mainly recommended for white wine, was also tested for red wines. These wines generally presented higher glycerol, reducing sugars and total dry matter, and lower alcohol content, in line with the current market trend. Significant sensory di erences among modalities were only obtained for three varieties. Results emphasized that grape variety is a relevant factor in studies with non-Saccharomyces yeastsinfo:eu-repo/semantics/publishedVersio

Predicting Crop Evapotranspiration under Non-Standard Conditions Using Machine Learning Algorithms, a Case Study for Vitis vinifera L. cv Tempranillo

This study focuses on assessing the accuracy of supervised machine learning regression algorithms (MLAs) in predicting actual crop evapotranspiration (ETc act) for a deficit irrigated vineyard of Vitis vinifera cv. Tempranillo, influenced by a typical Mediterranean climate. The standard approach of using the Food and Agriculture Organization (FAO) crop evapotranspiration under standard conditions (FAO-56 Kc-ET0) to estimate ETc act for irrigation purposes faces limitations in row-based, sparse, and drip irrigated crops with large, exposed soil areas, due to data requirements and potential shortcomings. One significant challenge is the accurate estimation of the basal crop coefficient (Kcb), which can be influenced by incorrect estimations of the effective transpiring leaf area and surface resistance. The research results demonstrate that the tested MLAs can accurately estimate ETc act for the vineyard with minimal errors. The Root-Mean-Square Error (RMSE) values were found to be in the range of 0.019 to 0.030 mm·h⁻¹. Additionally, the obtained MLAs reduced data requirements, which suggests their feasibility to be used to optimize sustainable irrigation management in vineyards and other row crops. The positive outcomes of the study highlight the potential advantages of employing MLAs for precise and efficient estimation of crop evapotranspiration, leading to improved water management practices in vineyards. This could promote the adoption of more sustainable and resource-efficient irrigation strategies, particularly in regions with Mediterranean climates.We acknowledge FCT Research Unit “GREEN-IT-Bioresources for Sustainability” (UIDB/04551/2020 and UIDP/04551/2020) for financial support. We also thank the support of the research units CITES, Centro de Investigación en Tecnología, Energía y Sostenibilidad, Universidad de Huelva, and LEAF (UID/AGR/04129/2019). We also address our acknowledgements to Herdade do Esporão (Reguengos de Monsaraz, Alentejo, PT) and Rui Flores for their contribution to field management of the experimental vineyard

Can Mediterranean terroirs withstand climate change ? Case studies at the Alentejo portuguese winegrowing region

XII Congreso Internacional TerroirClimate change introduced new challenges to vinegrowers in the Mediterranean areas such as the hot and dry winegrowing region of Alentejo, south Portugal. Warmer and drier conditions are harmful for grape yield and berry quality attributes and for vine’s longevity, mainly when optimal thresholds are exceeded. Therefore winegrowers are forced to move from rainfed to irrigated production systems making Alentejo’ wine production strongly based on available water resources for irrigation. This work aims to review and discuss ecophysiological and agronomical data obtained in irrigation trials set up at different terroirs of Alentejo. In the last four decades, classical bioclimatic temperature-based indices showed a significantly positive trend, while the dryness index present a negative trend over time. Furthermore, ecophysiological data collected in deficit irrigation experiments are reviewed and discussed, focusing on the effects of drought and heat stress on vigour, yield and berry composition. Emphasis is given on the indirect effects of leaf senescence on cluster exposure and consequences on berry temperature and composition. In order to promote the sustainability and quality of wine production in these hot and dry terroirs short- to longterm adaptation measures are suggested. The limitations and risks of using deficit irrigation during heat waves are also underlinedinfo:eu-repo/semantics/publishedVersio

Chemical composition and sensory profile of Syrah wines from semiarid tropical Brazil - rootstock and harvest season effects

This study aims to characterise the chemical compositions and sensorial profiles of wines made with Syrah grapes over two harvest seasons (first and second semester), over in different calendar years, from vines on two different rootstocks (1103P and IAC 313). Wine chemical composition and sensory profile were influenced by both rootstock and harvest season. Syrah wines on IAC 313 were favoured with higher concentrations of, petunidin 3-O-acetylglucoside (3.7 mg/L), malvidin 3-O-acetylglucoside (17.8 mg/L), malvidin 3-O-coumarylglucoside (4.4 mg/L), petunidin 3-O-coumarylglucoside (2.0 mg/L), peonidin 3-O-coumarylglucoside (1.4 mg/ L), monomeric flavanols (23.6 mg/L), oligomeric tannins (183.0 mg/L), total condensed tannins (1037.7 mg/L), dimer B1 (9.8 mg/L), B4 (5.0 mg/L), trimer C1 (3.1 mg/L) and calcium (80 mg/L). Syrah wines on 1103P had higher concentrations of total anthocyanins (375.6 mg/L, catechin (8.6 mg/L), epicatechin (12.6 mg/L), dimer B2 (21.0 mg/L), B1 3-O-gallate (1.8 mg/L), B2 3′-O-gallate (6.0 mg/L) and total flavanols (53.4 mg/L). The sensory profiles of the Syrah wines were influenced by rootstock followed by, mainly in relation to aromatic attributes. Syrah wines on IAC 313 were scored more highly by the tastersinfo:eu-repo/semantics/publishedVersio

Chemical and Sensorial Characterization of Tropical Syrah Wines Produced at Different Altitudes in Northeast of Brazil

Over the years, viticulture has expanded to new regions outside the temperate zones, such as Northeast Brazil, India, Thailand, Myanmar, Vietnam, Bangladesh and Venezuela, characterized by the production of tropical wines. It is important for the productive sector to comprehend the effects of grapevine interaction with the characteristics of each new region on wines composition. In this study, the composition of wines of Syrah from two regions with different altitudes in Northeast Brazil were analyzed by different methodologies to characterize chemical compounds as sugar, acids, minerals, phenolics (anthocyanins, flavonols, stilbenes and condensed tannins) and the sensory profile. The wines of the Bahia region (1100 m of altitude) obtained high concentrations for chemical parameters related to color, monomeric anthocyanins, stilbenes and monomeric and oligomeric tannins. Wines of the low altitude region, Pernambuco (350 m of altitude) were characterized by higher concentrations of flavonols (kaempferol, isorhamnetin, quercetin and rutin) and polymerized tannins. The chemical composition of wines from the two studied regions was influenced by altitude. A trend towards higher concentrations in most for phenolic compounds analyzed was observed in wines from the higher altitude region during the two years of study. Regarding the sensory profile, fruity, floral, herbaceous and empyreumatic attributes aromatic obtained highest scores in wines of the 350 m altitude region, the other attributes were dependent on the year of harvest

The role of soil temperature in mediterranean vineyards in a climate change context

The wine sector faces important challenges related to sustainability issues and the impact of climate change. More frequent extreme climate conditions (high temperatures coupled with severe drought periods) have become a matter of concern for the wine sector of typically dry and warm regions, such as the Mediterranean European countries. Soil is a natural resource crucial to sustaining the equilibrium of ecosystems, economic growth and people’s prosperity worldwide. In viticulture, soils have a great influence on crop performance (growth, yield and berry composition) and wine quality, as the soil is a central component of the terroir. Soil temperature (ST) affects multiple physical, chemical and biological processes occurring in the soil as well as in plants growing on it. Moreover, the impact of ST is stronger in row crops such as grapevine, since it favors soil exposition to radiation and favors evapotranspiration. The role of ST on crop performance remains poorly described, especially under more extreme climatic conditions. Therefore, a better understanding of the impact of ST in vineyards (vine plants, weeds, microbiota) can help to better manage and predict vineyards’ performance, plant-soil relations and soil microbiome under more extreme climate conditions. In addition, soil and plant thermal data can be integrated into Decision Support Systems (DSS) to support vineyard management. In this paper, the role of ST in Mediterranean vineyards is reviewed namely in terms of its effect on vines’ ecophysiological and agronomical performance and its relation with soil properties and soil management strategies. The potential use of imaging approaches, e.g. thermography, is discussed as an alternative or complementary tool to assess ST and vertical canopy temperature profiles/ gradients in vineyards. Soil management strategies to mitigate the negative impact of climate change, optimize ST variation and crop thermal microclimate (leaf and berry) are proposed and discussed, with emphasis on Mediterranean systemsinfo:eu-repo/semantics/publishedVersio

Suivi de l'évolution de la température du couvert végétal de deux variétés soumises a une irrigation déficitaire: un outil pour optimiser la géstion de l'eau ?

A better understanding of grapevine responses to drought and high air temperatures can help to optimize vineyard management to improve water use efficiency, yield and berry quality. Faster and robust field phenotyping tools are needed in modern precision viticulture, in particular in dry and hot regions such as the Mediterranean. Canopy temperature (Tc) is commonly used to monitor water stress in plants/crops and to characterize stomatal physiology in different woody species including Vitis vinifera. Thermography permits remote determination of leaf surface or canopy temperature in the field and also to assess the range and spatial distribution of temperature from different parts of the canopies. Our hypothesis is that grapevine genotypes may show different Tc patterns along the day due to different stomatal behaviour and heat dissipation strategies. We have monitored the diurnal and seasonal course of Tc in two grapevine genotypes, Aragonez (syn. Tempranillo) and Touriga Nacional subjected to deficit irrigation under typical Mediterranean climate conditions. Temperature measurements were complemented by determination of the diurnal course of leaf water potential (ψleaf) and leaf gas exchange. Measurements were done in two seasons (2013 and 2014) at different phenological stages: i) mid-June (green berry stage), ii) mid-July (veraison), iii) early August (early ripening) and iv) before harvest (late ripening). Correlations between Tc and minimal stomatal conductance will be presented for the two genotypes along the day. Results are discussed over the use of thermal imagery to derive information on genotype physiology in response to changing environmental conditions and to mild water stress induced by deficit irrigation. Strategies to optimize the use of thermal imaging in field conditions are also propose

Chemical and sensorial characterization of tropical syrah wines produced at different altitudes in northeast of the Brazil.

Over the years, viticulture has expanded to new regions outside the temperate zones, such as Northeast Brazil, India, Thailand, Myanmar, Vietnam, Bangladesh and Venezuela, characterized by the production of tropical wines. It is important for the productive sector to comprehend the effects of grapevine interaction with the characteristics of each new region on wines composition. In this study, the composition of wines of Syrah from two regions with different altitudes in Northeast Brazil were analyzed by different methodologies to characterize chemical compounds as sugar, acids, minerals, phenolics (anthocyanins, flavonols, stilbenes and condensed tannins) and the sensory profile. The wines of the Bahia region (1100 m of altitude) obtained high concentrations for chemical parameters related to color, monomeric anthocyanins, stilbenes and monomeric and oligomeric tannins. Wines of the low altitude region, Pernambuco (350 m of altitude) were characterized by higher concentrations of flavonols (kaempferol, isorhamnetin, quercetin and rutin) and polymerized tannins. The chemical composition of wines from the two studied regions was influenced by altitude. A trend towards higher concentrations in most for phenolic compounds analyzed was observed in wines from the higher altitude region during the two years of study. Regarding the sensory profile, fruity, floral, herbaceous and empyreumatic attributes aromatic obtained highest scores in wines of the 350 m altitude region, the other attributes were dependent on the year of harvest

Gestão da água e das águas residuais para uma viticultura e enologia sustentáveis no sul de Portugal - Revisão

Assessing sustainability of the wine industry requires improved characterization of its environmental impacts, namely in terms of water use. Therefore, quantification of water inputs and wastewater (WW) outputs is needed to highlight inefficiencies in wine production and related consequences for the environment. Water use and WW generation in irrigated viticulture and oenology remains insufficiently quantified for dry Mediterranean regions (e.g. South Portugal). This paper is focused on wine production under warm and dry climate conditions in the winegrowing region of Alentejo (South Portugal). This region experiences increasingly dry conditions, while the irrigated area keeps expanding, which puts exacerbates the pressure on existing local and regional water resources. Additionally, more erratic variation in climate conditions and the tendency for increasingly extreme climate events (e.g. heat waves) pose more challenges to Alentejo’s wine sector. We conclude that quantitative information on water use and management is not always easy to obtain or access, which hinders improved strategies and/or policies for water use at farm, winery and region-level. Up-to-date statistics and robust metrics can help to better characterize water use and WW flows for Alentejo’s wine region, while optimizing management in vineyards and wineries, in companies and region-wide. The paper is focused on a “Farm-Winery" scenario, which is the most common in South Portugal's wine sectorA avaliação da sustentabilidade da indústria vitivinícola requer uma caracterização detalhada do seu impacto ambiental, nomeadamente ao nível do factor água. A quantificação detalhada dos consumos de água e das águas residuais produzidas (WW) é crucial para identificação de ineficiências na indústria da vinha e do vinho. A utilização da água e a gestão dos efluentes em viticultura regada e na adega permanecem pouco quantificados nas regiões mediterrânicas. O presente trabalho centra-se na produção de vinho em condições de clima quente e seco, tomando como exemplo a região vitivinícola do Alentejo (Sul de Portugal). A região está sujeita a situações de seca mais frequentes e severas, enquanto a área regada continua em expansão, o que pressiona os recursos hídricos locais e regionais. Além disso, as condições climáticas altamente variáveis e a maior tendência para eventos climáticos extremos (e.g. ondas de calor) colocam desafios ao setor vitivinícola no Sul de Portugal. Concluímos que a informação quantitativa relativa ao uso e gestão de água não está sempre facilmente disponível, limitando a otimização de estratégias e/ou políticas para o uso da água ao nível da vinha, da adega e da região. Dados atualizados e indicadores robustos podem ajudar a caracterizar melhor o uso de água e a geração de água residual na região vitivinícola do Alentejo, otimizando a gestão na vinha e na adega, ao nível da empresa e da região. O artigo centra-se num cenário de produtor-engarrafador (“Farm-Winery”), que é o mais comum no setor vitivinícola no Sul de Portugalinfo:eu-repo/semantics/publishedVersio

Developmental Regulation of Transcription in Touriga Nacional Berries under Deficit Irrigation

Grapevine (Vitis vinifera L.) is one of the most economically important crops worldwide, especially due to the economic relevance of wine production. Abiotic stress, such as drought, may contribute to low yield, shifts in quality, and important economic loss. The predicted climate change phenomena point to warmer and dryer Mediterranean environmental conditions; as such, it is paramount to study the effects of abiotic stress on grapevine performance. Deficit irrigation systems are applied to optimize water use efficiency without compromising berry quality. In this research, the effect of two deficit irrigation strategies, sustained deficit irrigation (SDI) and regulated deficit irrigation (RDI), in the grape berry were assessed. The effects of different levels of drought were monitored in Touriga Nacional at key stages of berry development (pea size, véraison, and full maturation) through RNA-Seq transcriptome analysis and by specific differentially expressed genes (DEGs) monitoring through RT-qPCR. Handy datasets were obtained by bioinformatics analysis of raw RNA-Seq results. The dominant proportion of transcripts was mostly regulated by development, with véraison showing more upregulated transcripts. Results showed that primary metabolism is the functional category more severely affected under water stress. Almost all DEGs selected for RT-qPCR were significantly upregulated in full maturation and showed the highest variability at véraison and the lowest gene expression values in the pea size stageinfo:eu-repo/semantics/publishedVersio