Influence of must fining on wine pinking: relationship between electrochemical and colorimetric measurements and pinking attitude of wine

The main aim of WiSSaTech project (PRIN P2022LXY3A), supported by Italian Ministero dell’Università e della Ricerca and NextGenerationEU program, is to investigate eco-friendly and safe alternatives to sulphur dioxide (SO2) in wine production.

Varietal flavor is commonly known as the aromatic character of a wine in which the aroma of a particular grape variety predominates. However, not all varieties present particularly pronounced aromas. Therefore, different methods are constantly sought to enhance the aroma of wines with neutral aromatic characteristics, such as the use of glycosidases (1), certain yeast strains (2) or maceration with different agricultural products. In this work, aiming to improve the sensory profile together with the diversification of this product, white wines, derived from a neutral grape variety, were elaborated with the addition of mango peel by-products.

According to OIV reports, annual world wine consumption fluctuated around 240-245 mln hL over the past decade. The general market globalization has led to the situation when almost half of the consumed wine is exported to other countries. Of this volume, more than 60 mln hL are bottled still and sparkling wines.

Root system architecture (RSA) is important for soil exploration and edaphic resources acquisition by the plant, and thus contributes largely to its productivity and adaptation to environmental stresses, particularly soil water deficit. In grafted grapevine, while the degree of drought tolerance induced by the rootstock has been well documented in the vineyard, information about the underlying physiological processes, particularly at the root level, is scarce, due to the inherent difficulties in observing large root systems in situ. The objectives of this study were to determine genetic differences in the root architectural traits and their relationships to water uptake in two Vitis rootstocks genotypes (RGM, 140Ru) differing in their adaptation to drought. Young rootstocks grafted upon the Riesling variety were transplanted into cylindrical tubes and in 2D rhizotrons under two conditions, well watered and moderate water stress. Root traits were analyzed by digital imaging and the amount of transpired water was measured gravimetrically twice a week. Root phenotyping after 30 days reveal substantial variation in RSA traits between genotypes despite similar total root mass; the drought-tolerant 140Ru showed higher root length density in the deep layer, while the drought-sensitive RGM was characterised by shallow-angled root system development with more basal roots and a larger proportion of fine roots in the upper half of the tube. Water deficit affected canopy size and shoot mass to a greater extent than root development and architectural-related traits for both 140Ru and RGM, suggesting vertical distribution of roots was controlled by genotype rather than plasticity to soil water regime. The deeper root system of 140Ru as compared to RGM correlated with greater daily water uptake and sustained stomata opening under water-limited conditions but had little effect on above-ground growth. Our results highlight that grapevine rootstocks have constitutively distinct RSA phenotypes and that, in the context of climate change, those that develop an extensive root network at depth may provide a desirable advantage to the plant in coping with reduced water resources.

The sensory definition of the aging bouquet of red Bordeaux wines has been shown to be structured around seven main aromatic nuances: “undergrowth”, “spicy” “truffle”, “fresh red- and black-berry fruits”, “liquorice”, “mint”, and “toasted” (1). Some of these descriptors are also used to describe the aromatic notes of old Champagnes (2) suggesting common volatile compounds between these two types of wine.