Terroir 2016 banner
IVES 9 IVES Conference Series 9 Using a grape compositional model to predict harvest time and influence wine style

Using a grape compositional model to predict harvest time and influence wine style

Abstract

Linking wine composition to fruit composition is difficult due to the numerous biochemical pathways and substrate transformations that occur during fermentation. Grape composition regulates the production and final concentrations of most wine aroma compounds, as exemplified by methoxypyrazine and rotundone concentrations in wine being confidently predicted from the corresponding grape concentration. However, the final concentrations of many compounds in wines (aromatic and non-aromatic) are substantially dependent on the winemaking process.
The aim of this study was to better understand grape flavour evolution in relation to wine composition and subsequent wine style using sequential harvests (n=3). To achieve this goal, Shiraz was chosen as a model variety across two different climatic regions (warm-hot and cool-temperate) in New South Wales, Australia. The objective was not to compare the two regions but to assess the consistency of grape flavour evolution over the ripening period.

Irrespective of the region, a clear separation of samples was noted according to the harvest stage. Shiraz wines from the first harvest (H1) were associated with red fruit descriptors and higher acidity. Wines from the third harvest (H3) were correlated with dark fruit characters and a higher perception of alcohol. Higher concentrations of some higher alcohol acetates, dimethyl sulfide and lower concentrations of Z-3-hexenol, ethyl isobutyrate and ethyl leucate were measured in H3 wines.
Irrespective of the environment, this study demonstrated that in Shiraz, a common evolution of grape flavours exists, influencing the final wine sensory properties. Furthermore, during the late ripening stage, no direct nexus was observed between sugar concentration and grape and wine flavour evolution.

DOI:

Publication date: June 24, 2020

Issue: Terroir 2016

Type: Article

Authors

Alain DELOIRE (1), Katja ŠUKLJE (1), Guillaume ANTALICK (1), John BLACKMAN (1,2), Leigh SCHMIDTKE (1,2)

(1) National Wine and Grape Industry Centre, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia
(2) School of Agricultural and Wine Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia

Contact the author

Keywords

fruit and wine composition, wine sensory profile, sequential harvest, regionality, climate, volatiles, multivariate data analyses

Tags

IVES Conference Series | Terroir 2016

Citation

Related articles…

Ground vs trellis in rootstock cane production fields

Context and purpose of the study. The vine nursery sector is undergoing a transformation to meet growing environmental and sanitary demands.

Low and zero alcohol “wines”: impact of different dealcoholization processes on phenol profile and health benefits

Consumers’ demand for non-alcoholic wine has notably increased in the last years: this trend is a consequence of a growing interest in more healthy habits, and as a response to higher alcohol levels in wine due to climate change. In addition, drinking limitations due to physiological/pathological conditions (e.g., pregnancy, diabetes, hepatic disorders), driving regulations, ethical/religious considerations, and high import taxes on alcoholic beverages have positively influenced this marked (us$ 1.6 billion in 2021). International organisation of vine and wine (OIV) established that alcohol content defining wines must not be less than 8.5% vol, (OIV, 2017).

Sugar accumulation disorder Berry Shrivel – from current knowledge towards novel hypothesis

In contrast to fruit and grape berry ripening, the biological processes causing ripening disorders are often much less understood, although shriveling disorders of fruits are manifold and contribute to yield losses and reduced fruit quality worldwide. Shrinking berries are a common feature for all shriveling disorders in grapevine although their timing of appearance during the berry ripening process and their underlying induction processes distinct them from each other. The sugar accumulation disorder Berry Shrivel (BS) is characterized by a suppression of sugar accumulation short after veraison resulting in berries low in sugar content and anthocyanins in berry skins, while the organic acid content is similar. Recent studies analyzed the biochemical, morphological and molecular processes affected in BS berries and linked early changes to the period of ripening onset [1,2].

PHOTOCHEMICAL DEGRADATION OF TRYPTOPHAN IN MODEL WINE: IMPACT OF HEAVY METALS AND OXYGEN ON 2-AMINOACETOPHENONE FORMATION

The wine industry worldwide faces more and more challenges due to climate change, such as increased dryness in some areas, water stress, sunburn and early harvesting during hot summer temperatures¹. One of the resulting problems for the wine quality might be a higher prevalence of the untypical aging off-flavor (ATA)². A substance, which Rapp and Versini made responsible for ATA, is the 2-aminoace-tophenone (2-AAP)³. 2-AAP in wine causes a naphthalene, wet towels, wet wool, acacia flower or just a soapy note⁴.

Harvest dates – temperature relationships and thermal requirements of winegrape varieties in Greece: observed and future climate responses

Air temperature is arguably one of the most decisive factors for winegrape varieties developmental cycle, ripening potential and yield.