Terroir 2020 banner
IVES 9 IVES Conference Series 9 Understanding provenance and terroir in Australian Pinot noir

Understanding provenance and terroir in Australian Pinot noir

Abstract

Aims: This study aimed to (1) characterise colour and phenolic profiles of commercial Australian Pinot noir wines, (2) understand regional drivers of sensory and volatile profiles of commercial Australian Pinot noir wines, and (3) generate a deeper understanding of where Australian Pinot noir wines profiles sit in an international context.

Methods and Results: A broad set of commercial wines was sourced from 10 Australian Pinot noir producing wine regions (n=102) from two vintages (2015 and 2016). The modified Somers method was used for preliminary colour and phenolic analysis of the wines. Noticeable colour and phenolic profile differences were observed amongst the regions. For example, wines from Southern Tasmania were found to have consistently higher anthocyanin levels.

A sub-set of the broad group of Australian samples (n=80) was selected for grape-derived and fermentative volatile analysis (solid phase micro extraction coupled with gas chromatography–mass spectrometry) in addition to colour and phenolic analyses. Vintage was found to have a greater effect on aroma compounds than region.

A narrower set of commercial wines (n=15) was sourced from 5 Australian Pinot noir producing wine regions for in-depth sensory (Pivot© Profile) and grape-derived and fermentative volatile analysis (solid phase micro extraction coupled with gas chromatography–mass spectrometry). The sensory assessment results showed that wines from the Mornington Peninsula, and to a lesser extent two from Northern Tasmania were associated with ‘red fruits’ aroma, while the majority of wines from Adelaide Hills, Southern Tasmania, and Yarra Valley, were associated with the attributes ‘floral’ and ‘oaky’ aroma.

Conclusions:

Wine colour and phenolic analyses revealed demonstrable differences between Australian regions, and between the 2015 and 2016 vintages. Further investigation of volatile composition and sensory attributes of 2018 vintage wines showed regional sensory trends when it comes to Australia’s Pinot noir producing regions, with the Yarra Valley, Adelaide Hills and Mornington Peninsula showing similarities in their sensory profiles. However, from a sensory perspective Tasmanian Pinot noir tends to incorporate elements of all those regions into its sensory profiles, potentially reflecting the larger geographical size of the Tasmanian regions and greater terroir diversity in a single region.

Significance and Impact of the Study: The growing popularity of Pinot noir with Australian wine consumers underpins a need for better understanding the variety and its performance across varied terroirs. Many viticulturists and winemakers base agronomical and oenological practices on the colour and palate attributes of final wines. It is therefore important for the Australian wine industry to better understand the effect of regional compositional characteristics which potentially impact sensory attributes. These findings have the potential to support decision making for winemakers and viticulturists to achieve desired quality and stylistic outcomes and require further in-depth analysis of characteristics of the terroir. To the authors’ knowledge, this is the first study attempting to compare sensory and volatile profiles of Australian Pinot noir wines. Further studies including a greater number of samples and wine regions would provide more conclusive results, as would a comparative study using standardised winemaking protocols for fruit from a range of regions

DOI:

Publication date: March 25, 2021

Issue: Terroir 2020

Type : Video

Authors

Fiona Kerslake1*, Rocco Longo1, Wes Pearson2,3, Samantha Sawyer1, Angela Merry,1 Mark Solomon3, Luca Nicolotti3,5, Hanna Westmore1, Jacqui McRae3,6, Amanda Ylia3,5, Robert Dambergs,1,2,4

1 Horticulture Centre, Tasmanian Institute of Agriculture, University of Tasmania, Prospect, Tasmania, 7249, Australia
2 National Wine and Grape Industry Centre, Charles Sturt University, Wagga Wagga, New South Wales, 2650, Australia
3 The Australian Wine Research Institute, Urrbrae, South Australia, 5064, Australia
4 WineTQ, Ganmain, NSW, 2702, Australia 
5 Metabolomics South Australia, Urrbrae, South Australia, 5064, Australia
6School of Chemical Engineering and Advanced Materials, The University of Adelaide, SA, 5005, Australia

Contact the author

Keywords

Australian Pinot noir, regionality, aroma, Pivot© Profile

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Mechanisms involved in the heating of the environment by the aerodynamic action of a wind machine to protect a vineyard against spring frost

One of the main consequences of global warming is the rise of the mean temperature. Thus, the heat summation by the plants begins sooner in the early spring, and by cumulating growing degree-days, phenological development tends to happen earlier. However, spring frost is still a recurrent phenomenon causing serious damages to buds and therefore, threatening the harvests of the winegrowers. The wind machine is a solution to protect fruit crops against spring frost that is increasingly used. It is composed of a 10-m mast with a blowing fan at its peak. By tapping into the strength of the nocturnal thermal inversion, it sweeps the crop by propelling warm air above to the ground. Thus, stratification is momentarily suppressed. Furthermore, the continuous action of the machine, alone or in synergy, or the addition of a heater allow the bud to be bathed in a warmer environment. Also, the punctual action of the tower’s warm gust reaches the bud directly at each rotation period. All these actions allow the bud to continuously warm up, but with different intensities and over a different period. Although there is evidence of the effectiveness of the wind machines, the thermal transfers involved in those mechanisms raise questions about their true nature. Field measurements based on ultrasonic anemometers and fast responding thermocouples complemented by laboratory measurements on a reduced scale model allow to characterize both the airflow produced by the wind machine and the local temperature in its vicinity. Those experiments were realized in the vineyard of Quincy, in the framework of the SICTAG project. In the future paper, we will detail the aeraulic characterization of the wind machine and the thermal effects resulting from it and we will focus on how the wind machine warms up the local atmosphere and enables to reduce the freezing risk.

Upscaling the integrated terroir zoning through digital soil mapping: a case study in the Designation of Origin Campo de Borja

homogeneous zones by intersecting several partial zonings of major factors that influence vineyard growth. Each of them follows specific process from their corresponding disciplines. Soil zoning specifically refers to a Soil Resource Inventory map that has traditionally been generated by conventional soil mapping methods. These methods have shortcomings in reaching fine cartographic and categorical details and involve significant expenses, which undermines their applicability. A new framework named Digital Soil Mapping has introduced quantitative models by statistical techniques to establish soil-landscape relationships and is able to provide intensive scale cartography.

In the present study, a microzoning at 1:10.000 scale is generated from an initial zoning, where the conventional soil map with polytaxic map units is replaced by a new one from digital techniques that disaggregates them. The comparison between the zonings considers a quantitative evaluation of capability for each Homogeneous Terroir Unit by means of the Viticultural Quality Index and its categorization based on its distribution by map. The spatial intersection of both maps gives rise to a confusion matrix in which the flows of class variations after the substitution are assessed.

The results show a five-fold increase in the number of Homogeneous Terroir Units identified and a larger differentiation among them, evidenced by a wider range in the capability index distribution. Both elements are accompanied by an increase in the detection of areas of higher potential within previously undervalued uniform zones.These features are a direct effect of the improvements brought by Digital Soil Mapping techniques and would verify the advantages of their implementation in the Integrated Terroir zoning. Eventually, such new highly detailed terroir units would benefit precision viticulture and sustainable management practices.

Anthocyanin profile is differentially affected by high temperature, elevated CO2 and water deficit in Tempranillo (Vitis vinifera L.) clones

Anthocyanin potential of grape berries is an important quality factor in wine production. Anthocyanin concentration and profile differ among varieties but it also depends on the environmental conditions, which are expected to be greatly modified by climate change in the future. These modifications may significantly modify the biochemical composition of berries at harvest, and thus wine typicity. Among the diverse approaches proposed to reduce the potential negative effects that climate change may have on grape quality, genetic diversity among clones can represent a source of potential candidates to select better adapted plant material for future climatic conditions. The effects of individual and combined factors associated to climate change (increase of temperature, rise of air CO2 concentration and water deficit) on the anthocyanin profile of different clones of Tempranillo that differ in the length of their reproductive cycle were studied. The aim was to highlight those clones more adapted to maintain specific Tempranillo typicity in the future. Fruit-bearing cuttings were grown in controlled conditions under two temperatures (ambient temperature versus ambient temperature + 4ºC), two CO2 levels (400 ppm versus 700 ppm) and two water regimes (well-watered versus water deficit), both in combination or independently, in order to simulate future climate change scenarios. Elevated temperature increased anthocyanin acylation, whereas elevated CO2 and water deficit favoured the accumulation of malvidin derivatives, as well as the acylation and tri-hydroxylation level of anthocyanins. Although the changes in anthocyanin profile observed followed a common pattern among clones, such impact of environmental conditions was especially noticeable in one of the most widely distributed Tempranillo clones, the accession RJ43.

Modeling the suitability of Pinot Noir in Oregon’s Willamette Valley in a changing climate

Air temperature is the key driver of grapevine phenology and a significant environmental factor impacting yield and quality for a winegrape growing region. In this study the optimal downscaled CMIP5 ensemble for computing thegrowing season average temperature (GST) viticulture climate classification index was determined to spatially compute on a decadal basis predictions of the GST climate index and the grapevine sugar ripeness (GSR) model for Pinot Noir throughout the Willamette Valley (WV) American Viticultural Area (AVA). Forecasts for average temperature and a 220 g/L target sugar concentration level were computed using daily Localized Constructed Analogs (LOCA) downscaled CMIP5 historic and Representative Concentration Pathways (RCP) future climate projections of minimum and maximum daily temperature. We explore spatiotemporal trends of the GST climate classification index and Pinot Noir specific applications of the GSR phenology model for the WV AVA. Spatiotemporal computations of the GST climate index and Pinot Noir specific applications of the GSR model enable the opportunity to explore relationships between their computed values with one intent being to provide updated GST ranges that better align with current temperature-based modeling understanding of Pinot Noir grapevine phenology and the viticultural application of LOCA CMIP5 climate projections for the WV AVA. The Pinot Noir specific applications of the GSR model or the GST index with updated bounds indicate that the percent of the WV AVA area suitable for Pinot Noir production is currently at or near its peak value in the upper 80s to lower 90s of this century.

Effect of vigour and number of clusters on eonological parameters and metabolic profile of Cabernet Sauvignon red wines

Vegetative growth and yield are reported to affect grape and wine quality. They can be controlled through different techniques linked to vine management. The objective of this research was to determine the effect of vine vigour and number of clusters per vine on physicochemical composition and phenolic profile of red wines. The experiment was carried out during two vegetative cycles, with cv. Cabernet Sauvignon grafted onto Paulsen 1103. Three vine vigour were defined, according to shoot weight at previous harvests, being low, medium and high. Five treatments of number of clusters were used for each vigour, with 15, 22, 29, 36, and 45 clusters per vine. Grapes from all treatments were harvested in the same day from Brix and total acidity criteria. Thirty days after bottling, classical analyzes and phenolic compounds were performed. As results, different responses were obtained from each vintage. In 2020, a dry season from veraison to harvest, grapes and wines obtained from low vigour treatment and 45 clusters per vine was the highest in sugar and alcohol content respectively, while grapes and wines from high vigour and 15 clusters presented the lowest sugar and alcohol content. Total anthocyanins were higher in treatment with low vigour and 15 clusters, while the lowest amounts were found in low vigour with 45 clusters, as well as medium and high vigour with 36 clusters per vine. Total tannins were higher in high vigour with 22 clusters and medium vigour with 29 clusters, while were lower in low vigour with 36 clusters. In 2021, a wet season at harvest, responses were different, and great variations were observed between treatments. As conclusions, yield and vine vigour had strong influence on grape and wine quality, promoting different enological potentials on which can be indicated/used for aging strategies of red and even rosé wines.