Ugni blanc berry and wine composition impacted by thirteen rootstocks

Grapes from warm(ing) climates often contain excessive sugars but lack acidity. This can lead to highly alcoholic wines with compromised stability and balance. The yeast Lachancea thermotolerans can ameliorate such wines due to its metabolic peculiarity – partial fermentation of sugars to lactic acid. This study aimed to elucidate the population-wide diversity in L. thermotolerans, whilst selecting superior strains for wine sector. An extensive collection of isolates (~200) sourced from different habitats worldwide was first genotyped on 14 microsatellite loci. This revealed differentiation of L. thermotolerans genetic groups based on the isolation substrate and geography. The 94 genotyped strains were then characterised in Vitis vinifera cv. Chardonnay fermentations.

To assess the relationship between the reported low-stability of Tannat colour during wine storage and its pigment composition and evolution

The aim of this study is to provide an overview of the terroir of Saint-Romain, Burgundy, based on three main information sources: official data relating to vines (CVI), soil cartography and a survey of winegrowers’ practices.

In a collective marketing strategy, the Protected Designation of Origin (PDO) can be used as a quality indicator. To highlight terroir specificities, it is useful to know how the wines are positioned on the local, national or international market from a sensory point of view. This is especially true for a comparison of varietal wines (e.g. Sauvignon blanc). We focus on the case of two closed Loire Valley PDO (France): Quincy and Reuilly. Three distinct tastings were organized. Firstly, at the local level comparing the 2 PDO (11 and 9 wines, 17 professional assessors); secondly at a regional level adding 3 closed PDO: Menetou-Salon, Sancerre and Pouilly-Fumé (3 wines per PDO, 16 assessors) and thirdly at an international level comparing these 5 PDO with Sauvignon Blanc wines coming from South Africa, New Zealand and Chile (1 to 3 wines per PDO, 19 assessors). All the wines were from the 2019 vintage and were considered to have a traditional elaboration process without contact with oak. A sensory descriptive analysis was performed using an aroma wheel allowing to combine a Check-All-That-Apply methodology, often used in sensory benchmarking, with a hierarchical structuration of the attributes. The aim is to facilitate data acquisition in a professional context without common training, to consider the hierarchical relationships among the attributes during the data analysis and to be able to characterize wines with a large range of sensorial variability. We use univariate, multivariate and clustering analyses. Similarities and differences between Quincy and Reuilly PDO wines and other Sauvignon blanc wines were identified. Specific attributes can distinguish the two PDO and different proximities exist with other local PDO, while clear differences were observed compared to international wines. Our study contributes to propose and discuss a method to do a wine sensory benchmarking highlighting sensory specificities linked to origin.

In recent studies, several grapevine trunk pathogen complexes have been identified from grapevines in South Africa. These pathogens include Eutypa lata, Phaeomoniella chlamydospora, Phaeoacremonium sp., Botryosphaeria sp. and Phomopsis sp. Trunk diseases lead to reduced yield, and grape quality as well as a decline