Best talk award at wine industry event

08 July 2016
Dr Sarah Knight
Dr Sarah Knight

New Zealand Winegrowers’ Grape Days is an industry lead event summarising the previous growing season and the cutting-edge research funded either in whole or part by membership levies. Presenting to roughly 600 industry members in three winegrowing regions (Hawke’s Bay, Marlborough and Central Otago), Grape Days comprise a travelling roadshow of scientists and industry representatives. This year, Dr Sarah Knight, a Reserch Fellow from the School of Biological Sciences at the University of Auckland, was invited to share her research on native New Zealand yeasts and terroir and was awarded the prize for Best Talk at the final session in Central Otago.

Her research, under the supervision of Assoc. Prof. Mat Goddard (SBS) and in collaboration with Dr Steffen Klaere (Statistics) and Dr Bruno Fedrizzi (Chemistry), provided the first objective evidence that microbes contribute to the regional flavours and aromas that are so well known in wine. Also known as terroir, these regional wine properties are traditionally attributed to differences in soil, climate, topography and winemaking practices; however there is increasing evidence showing that microbial communities and populations vary by geographic region. When combined with previous research showing that different species and strains of yeast involved in fermentation produce different flavours and aromas in wine, it is logical to suggest that these regionally distinct yeast populations may contribute to regional wine properties.

By using the genetically characterised NZ population of Saccharomyces cerevisiae (the main fermenting wine yeast), Sarah performed ferments in Sauvignon Blanc juice and analysed a range of wine properties and chemical compounds in the final wine. Statistical analyses confirmed that strains of S. cerevisiae isolated in different geographic regions produced distinct chemical profiles in wine. These findings have wide-ranging implications for sustainable agriculture and highlight the commercial implications of preserving the microbial biodiversity in vineyards and potentially other agricultural systems. This work was published in Scientific Reports and is one of the top 100 read articles currently approaching 10,000 views.