IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Transition metals and light-dependent reactions: application of a response surface methodology approach

Transition metals and light-dependent reactions: application of a response surface methodology approach

Abstract

Light-induced reactions can be responsible for detrimental changes of white and rosé wines. This is associated to the photo-degradation of riboflavin (RF) and of methionine (Met) causing the appearance of light-struck taste (LST). The fault is associated to the formation of volatile sulfur compounds (VSCs), namely methanethiol (MeSH) and dimethyl disulfide (DMDS), leading to cooked cabbage, onion and garlic odours-like [1]. Aside these pathways, other oxidative reactions can occur involving iron and copper that can generate quinones. Moreover, the ability of copper in binding the compounds containing a free thiol group is well known. 
This study aimed to evaluate for the first time the combined effect of iron, copper, and oxygen on LST formation in model wine.
A Surface Response Methodology approach was used considering 3 variables, as iron, copper and oxygen. Based on the experimental design, 15 runs (light-exposed and kept in the dark) were performed in model wine. Furthermore, to better understand the influence of phenolics, the same experimental design was applied in the presence of catechin and caffeic acid, used as model phenols. RF, Met, VSCs, and sensory were determined.
No RF was found in any light-exposed sample analysed. The major decrease of Met was revealed in model solution in which MeSH and DMDS were the highest. The presence of phenolics limited the degradation of Met and, consequently, the formation of MeSH and DMDS. In particular, in most of the runs where caffeic acid was added, VSCs were lower than in the runs in model wine and in the presence of catechin. The presence of iron (10 mg/L and 5 mg/L with oxygen 3 mg/L) led to a higher content of mercaptans in model wine as well as in the presence of catechin and caffeic acid. Our findings suggest that besides RF and Met, the susceptibility of a wine in developing LST appeared to be related to the presence of transition metals as well as to the different phenols that would ordinarily be present in wine. 
This study represents a further step for the deeper comprehension of the photo-induced reactions allowing to pursue the LST prevention in white wine.

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Fracassetti Daniela1, Jeffery David2, Ballabio Davide3 and Tirelli Antonio1

1Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via G. Celoria 2, 20133 Milan, Italy
2Department of Wine Science and Waite Research Institute, The University of Adelaide
3Department of Earth and Environmental Sciences, University of Milano-Bicocca

Contact the author

Keywords

riboflavin, methionine, catechin, caffeic acid, volatile sulfur compounds

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Variety and climatic effects on quality scores in the Western US winegrowing regions

Wine quality is strongly linked to climate. Quality scores are often driven by climate variation across different winegrowing regions and years, but also influenced by other aspects of terroir, including variety. While recent work has looked at the relationship between quality scores and climate across many European regions, less work has examined New World winegrowing regions. Here we used scores from three major rating systems (Wine Advocate, Wine Enthusiast and Wine Spectator) combined with daily climate and phenology data to understand what drives variation across wine quality scores in major regions of the Western US, including regions in California, Oregon and Washington. We examined effects of variety, region, and in what phenological period climate was most predictive of quality. As in other studies, we found climate, based mainly on growing degree day (GDD) models, was generally associated with quality—with higher GDD associated with higher scores—but variety and region also had strong effects. Effects of region were generally stronger than variety. Certain varieties received the highest scores in only some areas, while other varieties (e.g., Merlot) generally scored lower across regions. Across phenological stages, GDD during budbreak was often most strongly associated with quality. Our results support other studies that warmer periods generally drive high quality wines, but highlight how much region and variety drive variation in scores outside of climate.

Analysis of Cabernet Sauvignon and Aglianico winegrape (V. vinifera L.) responses to different pedo-climatic environments in southern Italy

Water deficit is one of the most important effects of climate change able to affect agricultural sectors. In general, it determines a reduction in biomass production, and for some plants, as in the case of grapevine, it can endorse fruit quality. The monitoring and management of plant water stress in the vineyard

A blueprint for managing vine physiological balance at different spatial and temporal scales in Champagne

In Champagne, the vine adaptation to different climatic and technical changes during these last 20 years can be seen through physiological balance disruptions. These disruptions emphasize the general grapevine decline. Since the 2000s, among other nitrogen stress indicators, the must nitrogen has been decreasing. The combination of restricted mineral fertilizers and herbicide use, the growing variability of spring rainfall, the increasing thermal stress as well as the soil type heterogeneity are only a few underlying factors that trigger loss of physiological balance in the vineyards. It is important to weigh and quantify the impact of these factors on the vine. In order to do so, the Comité Champagne uses two key-tools: networking and modelization. The use of quantitative and harmonized ecophysiological indicators is necessary, especially in large spatial scales such as the Champagne appellation. A working group with different professional structures of Champagne has been launched by the Comité Champagne in order to create a common ecophysiology protocol and thus monitor the vine physiology, yearly, around 100 plots, with various cultural practices and types of soil. The use of crop modelling to follow the vine physiological balance within different pedoclimatic conditions enables to understand the present balance but also predict the possible disruptions to come in future climatic scenarios. The physiological references created each year through the working group, benefit the calibration of the STICS model used in Champagne. In return, the model delivers ecophysiology indicators, on a daily scale and can be used on very different types of soils. This study will present the bottom-up method used to give accurate information on the impacts of soil, climate and cultural practices on vine physiology.

How can historical cultivars mitigate the effects of climate change?

IFV, INRAe and the national network “Partenaires de la Sélection Vigne” representing 37 organizations from the different wine regions, have been working increasingly closely over the last 2 decades towards the preservation of the French varietal patrimony. There are approximately 600 patrimonial varieties according to INRAe and SupAgro Montpellier experts, including ancient cultivars (400) and intravarietal crossbreeds obtained since the 19th century. In the context of a drastic reduction in such varieties from the mid 1980’s in favor of mainstream varieties, it was essential to carry out an inventory of old vines and vineyards. INRAe Vassal collection plays a key role here as it holds the largest diversity available, along with a rich bibliography and herbariums, offering us the opportunity to document and double check the identity of a cultivar, consolidating the expertise of ampelographers. The work is carried out in several stages, from verifying the existence of a variety in a small region, through to rehabilitation. During this session, the authors present the process that leads to the official registration of a variety. After this, IFV selection center takes over to initiate the process of selection and propagation. A specific focus within regions such as the Alps, Champagne and the South-West will provide details of the full procedure. Bia, Bouysselet, Chardonnay rose, Mecle and the aptly named Tardif, are some of the cultivars that have followed this procedure. Furthermore, a recent regulation established by INAO on “varieties of interest for adaptation purposes” might boost uptake by growers. Since 2006, 36 historical cultivars have been registered. Most of these have been neglected in the past due to late maturity, lack of sugar and high titratable acidity at harvest time. Such characteristics are today considered as positive qualities, not only in mitigation of the effects of climate change, but also as an opportunity for restoring diversity…

Local adaptation tools to ensure the viticultural sustainability in a changing climate

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...