Microbes beyond the soil: evaluating how vineyard management might affect communities and their effect on a key set of esters and thiols

There is significant market and industry desire to produce wine in ways that maximises the quality and distinctness but does so using environmentally responsible methods that minimise impact and increase the longevity of vineyards. The MBIE Vineyard Ecosystems (VE) programme makes a paradigm shift and takes a holistic approach and focusses on a core set of sites and evaluates the impact of two main management styles on vineyard health, quality and longevity.

However, the VE programme does not consider the effects of these different management approaches on the microbial biodiversity on ripe fruit and the resulting juice. This is important as these microbial communities play a role in defining the complex mix of compounds that affect wine aroma and flavour. This project will focus on Sauvignon blanc due to its economic weight and that we understand these systems best in terms of microbial ecology and wine chemistry. While Saccharomyces yeasts are the main species that drive fermentation, the range of other species that dominate on ripe fruit, in juice and early ferment also affect key flavour compounds. This project proposes to evaluate the species present on ripe grapes and see if and how these might change leading up to harvest, into the winery and early ferment. Importantly the project will evaluate how vineyard management might affect these communities and their effect on a key set of esters and thiols.

This project uses a combination of next-generation DNA sequencing to evaluate aspects of microbial community ecology and population biology and understand how this relates to fungal populations associated with vines and winemaking. It will build on a body of work in this area at the University of Auckland (http://www.goddardlab.auckland.ac.nz), be strongly aligned with the Vineyard Ecosystem’s program (https://www.nzwine.com/en/innovation/innovation-new-zealand-wine/vineyard-ecosystems/), and collaborate strongly with Plant and Food Research (http://www.plantandfood.co.nz) and New Zealand Winegrowers (https://www.nzwine.com/en).

Formal application should comprise a CV and covering letter to Dr Sarah Knight by 1st August at [Email Address Removed].

Informal enquires may be addressed to both Dr Sarah Knight and Prof Matthew Goddard ([Email Address Removed]).