Macrowine 2021
IVES 9 IVES Conference Series 9 Ageing of Sauvignon Blanc white wines with Specific Inactivated Dry Yeasts: Effect on physical and chemical characteristics

Ageing of Sauvignon Blanc white wines with Specific Inactivated Dry Yeasts: Effect on physical and chemical characteristics

Abstract

It is well known that polysaccharides, mainly mannoproteins, play an important role on physical, chemical and sensory quality of wines. The ageing of white wines on lees is used in order to release higher amounts of polysaccharides by the autolytic processes in order to obtain higher-quality wines. However, this technique is too slow, because the temperature and pH conditions are not the most suitable for this process. In addition, it can also involve certain disadvantages such as a greater demand on winery resources, a longer period of wine storage, the appearance of reduction notes and some microbiological alterations. Continuously, companies are looking for the development of new products from yeast, commonly known as yeast derivatives, which are rich in polysaccharides and can guarantee the improvements of the ageing on lees but minimizing its disadvantages. These products are commonly classified as inactivated dry yeast, yeast autolysates, yeast cell walls, yeast proteic extracts and purified mannoproteins as it is defined in the Enological Codex (OIV). Normally, the yeast derivatives most used during the short ageing of wines are specific inactivated dry yeast (SIDY) selected for their high content of mannoproteins. However, there is a great variety of these products which can release different contents of polysaccharides (quantity and quality) and produce different effects on the quality of wines. For these reasons, the aim of this work was to study the effect of two different SIDY on the polysaccharidic content, colour and polyphenolic compositions of Chilean Sauvignon Blanc white wines. The wines were analysed after 2 months of treatment, 3 and 6 months in bottle. Four different fractions of polysaccharides, with different molecular weight, were identified and quantified. Wines treated with both SIDY had a higher content of polysaccharides after the ageing period and during bottle storage than control wines. No differences were found between both SIDY used. No significant difference was found in the content of total polyphenols between treated and control wines. However, some differences were found in the low molecular weight phenolic compounds (LMWPC) but depended on the SIDY used, the ageing period and the LMWPC analyzed. The use of SIDY contributed to improve the colour of wines which had a lower colour intensity and lower values of “a and b” CIELab parameters, which can allow to avoid or reduce the browning of wines.

Acknowledgements: This study was supported by CONICYT-Chile PAI N° 781403003 and FONDECYT N°1140882 Projects.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Rubén Del Barrio Galán*, Álvaro Peña-Neira, Andrés Gómez Parrini

*Lallemand Inc chile y Compania limitada

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Use of glutathione under different grape processing and winemaking conditions and its impact on the formation of sulfide off-flavors, colour, and sensory characteristics of Riesling, Sauvignon blanc, and Chardonnay

The use of glutathione (GSH) in winemaking has been legitimated recently, according to OIV resolutions OENO 445-2015 and OENO 446-2015 a maximum dose of 20 mg/L is now allowed to use in must and wine. Several studies have proven the benefits of GSH, predominantly in Sauvignon blanc. Thus, oxidative coloration of must and wine is limited, aroma compounds such as volatile thiols are preserved, and the development of ageing flavors such as sotolon and 2-aminoacetophenone is impeded. The protective effect may be explained by the high affinity of GSH to bind o-quinones which are formed during phenolic oxidation and which are known to initiate browning and other oxidative changes. Some researchers have proposed the hydroxycinnamic acid to GSH ratio (HGR) as an indicator of oxidation susceptibility of must and could show that lower ratios yielded lighter musts.

Evaluation of Polarized Projective Mapping as a possible tool for attributing South African Chenin blanc dry wine styles

Multiple Factor Analysis (MFA) According to the Chenin blanc Association of South Africa, there are three recognized dry wine styles, Fresh and Fruity (FF), Rich and Ripe Unwooded (RRU), and Rich and Ripe Wooded (RRW), classically attributed with the help of sensory evaluation. One of the “rapid methods” has drawn our attention for the purpose of simplifying and making style attribution for large sample sets, evaluated during different sessions, more robust. Polarized Projective Mapping (PPM) is a hybrid of Projective Mapping (PM) and Polarised Sensory Positioning (PSP). It is a reference-based method in which poles
(references) are used for the evaluation of similarities and dissimilarities between samples.

An excessive leaf-fruit ratio reduces the yeast assimilable nitrogen in the must

Yeast assimilable nitrogen (YAN) in the grape must is a key variable for wine quality as a source of aroma precursors. In a situation of YAN deficiency, a foliar urea application upon the vine at veraison enhances YAN concentration and facilitates must fermentation. In 2013, Agroscope investigated the impact of leaf-fruit ratio on the nitrogen (N) assimilation and partitioning in grapevine Vitis vinifera cv. Chasselas following foliar-urea application with the aim of improving its efficiency on the YAN concentration.

Study of the colour and phenolic evolution of three different tannin/anthocyanin ratios over time in a model wine

Phenolic compounds are important quality indicators in red wine. A large number of polyphenols play an important role in wine development, contributing to the colour and the sensory perception of the wines. Anthocyanins are the pigments responsible for the colour in young red wines while tannins are the principal contributors to the bitterness and the astringency of the wines. Wine polyphenols are considered more complex molecules than grape phenolics, due to the enormous number of chemical reactions which take place during the entire winemaking process and storage, forming more stable compounds.

Anti/prooxidant activity of wine polyphenols in reactions of adrenaline auto-oxidation

Adrenaline (epinephrine) belongs to catecholamine class. It is a neurotransmitter and both a hormone which is released by the sympathetic nervous system and adrenal medulla in response to a range of stresses in order to regulate blood pressure, cardiac stimulation, relaxation of smooth muscles and other physiological processes. Adrenaline exhibits an effective antioxidant capacity (1). However, adrenalin is capable to auto-oxidation and in this case it generates toxic reactive oxygen intermediates and adrenochrome. Under in vitro conditions, auto-oxidation of adrenaline occurs in an alkaline medium (2).