terclim by ICS banner
IVES 9 IVES Conference Series 9 OENOLOGICAL STRATEGIES FOR THE REMOVAL OF PINKING IN WHITE WINE

OENOLOGICAL STRATEGIES FOR THE REMOVAL OF PINKING IN WHITE WINE

Abstract

The pinking of in white wine is the turning of color from yellow to salmon hue. White wines obtained from certain grape varieties (e.g. Chardonnay, Sauvignon blanc, Riesling, Trebbiano di Lugana) showed to be susceptible to pinking [1] that has been evaluated by an assay providing the addition of hydrogen peroxide. Even if its appearance does not seem to affect the sensory properties [2], strategies are necessary for its removal. Nowadays, the treatment with polyvinylpolipirroline (PVPP) was reported to significantly decrease the pink color [3]. To assess other additives and co-adjuvants suitable for pinking removal, this study aimed to identify the wine treatment(s) most effective for achieving this purpose.

A white wine showing the pinking fault was added with several additives and co-adjuvants, including active charcoals (bleaching and deodorizing), bentonites, gelatine, PVPP, PVI/PVP, chitosan, potassium caseinate, kaolin, zeolite, silica, calcium phytate, oenological tannins (oak and grape skin), glutathione, ascorbic acid (without/with sulfur dioxide) yeast derivatives for a total of 23 removal assays. The wines were stored up to 26 days and their susceptibility to pinking was carried out at 4 sampling points (day 1, 5, 15 and 26) through the hydrogen peroxide test. The wine was considered susceptible to pinking (SP) when an increase of 5 mAU was observed at 500 nm [4]. Moreover, the pink color index at 500 nm (wit-hout hydrogen peroxide) was determined.

No change in the pink color index was found with the exception of potassium caseinate. Some of the tested additives and co-adjuvants were not effective in limiting SP, including active charcoals, bentonite, gelatine, kaolin, zeolite, silica, grape skin tannin, glutathione and ascorbic acid. For some of them, an increased SP was evidenced (e.g. kaolin, zeolite, grape skin tannin). The treatment with PVI/PVP strongly decreased the pinking susceptibility already after 1 day. In this condition, the wine was not SP anymore at day 15. For this sampling time, three of the yeast derivatives tested, chitosan, PVPP, potassium caseinate and oak tannins limited the pinking susceptibility. The addition of PVPP, the mainly used co-adjuvant, did not result the most relevant one to solve such significant color change. Further study will investigate the selected additives and co-adjuvants in other pink wines as well as in combination in order to identify the most promising treatment for the pinking removal.

 

1. Andrea-Silva, J., Cosme, F., Ribeiro, L. F., Moreira, A. S. P., Malheiro, A. C., Coimbra, M. A., Domingues, M. R. M., & Nunes, F. M. (2014). Origin of the pinking phenomenon of white wines. Journal of Agriculture and Food Chemistry, 62, 5651–5659. https://doi.org/10.1021/jf500825h
2. Nel, A.P., du Toit, W.J., & van Jaarsveld, F.P. (2021). Sensory evaluation of pinked Sauvignon blanc wines. South African Journal of Enology and Viticulture, 42, 175-183. http://dx.doi.org/10.21548/42-2-4316
3. Simpson R., Miller G., Orr L. (1982). Oxidative pinking of white wines: recent observations. Food technology in Australia, 34, 
44- 47.
4. Simpson R.F. (1977). Oxidative pinking in white wines. Vitis, 16, 286-286.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Daniela Fracassetti1,*, Francesca Domenighini¹, Alessio Altomare¹, Maria Manara², Antonio Tirelli¹

1. Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via G. Celoria 2, 20133 Milan, Italy
2. Research and Developments, Dal Cin S.p.a., Via I Maggio 67, 20863 Concorezzo, Italy 

Contact the author*

Keywords

Wine treatments, PVI/PVP, Chitosan, Yeast derivatives

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

DEVELOPMENT OF BIOPROSPECTING TOOLS FOR OENOLOGICAL APPLICATIONS

Wine production is a complex biochemical process that involves a heterogeneous microbiota consisting of different microorganisms such as yeasts, bacteria, and filamentous fungi. Among these microorganisms, yeasts play a predominant role in the chemistry of wine, as they actively participate in alcoholic fermentation, a biochemical process that transforms the sugars in grapes into ethanol and carbon dioxide while producing additional by-products. The quality of the final product is greatly influenced by the microbiota present in the grape berry, and the demand for indigenous yeast starters adapted to specific grape must and reflecting the biodiversity of a particular region is increasing. This supports the concept that indigenous yeast strains can be associated with a “terroir”.

PROBING GRAPEVINE-BOTRYTIS CINEREA INTERACTION THROUGH MASS SPECTROMETRY IMAGING

Plants in their natural environment are in continuous interaction with large numbers of potentially pathogenic and beneficial microorganisms. Depending on the microbe, plants have evolved a variety of resistance mechanisms that can be constitutively expressed or induced. Phytoalexins, which are biocidal compounds of low to medium molecular weight synthesized by and accumulated in plants as a response to stress, take part in this intricate defense system.1,2
One of the limitations of our knowledge of phytoalexins is the difficulty of analyzing their spatial responsiveness occurring during plant- pathogen interactions under natural conditions.

PHOTO OXIDATION OF LUGANA WINES: INFLUENCE OF YEASTS AND RESIDUAL NITROGEN ON VSCS PROFILE

Lugana wines are made from Turbiana grapes. In recent times, many white and rosé wines are bottled and stored in flint glass bottles because of commercial appeal. However, this practice could worsen the aroma profile of the wine, especially as regards the development of volatile sulfur compounds (VSCs). This study aims to investigate the consequences of exposure to light in flint bottles on VSCs profile of Lugana wines fermented with two different yeasts and with different post-fermentation residual nitrogen.

MOVING FROM SULFITES TO BIOPROTECTION: WHICH IMPACT ON CHARDONNAY WINE?

Over the last few years, several tools have been developed to reduce the quantity of sulfites used during winemaking, including bioprotection. Although its effectiveness in preventing the development of spoilage microorganisms has been proven, few data are available on the impact of sulfite substitution by bioprotection on the final product. The objective of this study was therefore to characterize Chardonnay wines with the addition of sulfite or bioprotection in the pre-fermentation stage. The effects of both treatments on resulting matrices was evaluated at several scales: analysis of classical oenological parameters, antioxidant capacity, phenolic compounds, non-volatile metabolome and sensory profile.

DETERMINATION OF MINERAL COMPOSITION IN CV. TERAN (VITIS VINIFERA L.) RED WINE AFFECTED BY PRE-FERMENTATIVE MASH COOLING, HEATING, SAIGNÉE TECHNIQUE AND PROLONGED POST-FERMENTATIVE MACERATIONS

This study aimed to determine mineral composition in red wine obtained from cv. Teran (Vitis vinifera L.), autochtonous Croatian grape variety. Six different vinification treatments, including the control treatment (7-day standard maceration), were performed to study the effects of: 48-hour pre-fermentative mash cooling (8 °C) followed by prolonged post-fermentative maceration of 13 days (C15), 28 days (C30), and saignée technique (juice runoff) proceeded with prolonged post-fermentative maceration of 13 days (CS15); and effect of 48-hour heating (50 °C) followed by prolonged post-fermentative maceration of 13 days (H15) and 28 days (H30) on macro- and microelements in wine.