Analysing Sauvignon Blanc Flavours in Wine

Sauvignon Blanc has been the focus of wine aroma research for a number of years. This has been due to the unique and distinct characters of New Zealand produced Sauvignon Blanc wines. The “Sauvignon Blanc Project” has been multi-faceted and has included input from a number of research organizations.

The Department of Chemistry, Auckland University have been looking at:

• The chemical and sensory profiles of NZ Sauvignon Blanc wines
• Identifying new aroma compounds
• Examining the stability of these compounds during winemaking and bottle aging.

The Auckland School of Biological Sciences has been developing yeast strains with differing efficiencies of conversion of the various volatile compound precursors. This could allow winemakers to use different yeasts to produce wines with different flavour characteristics.  Plant & Food Research Auckland has been investigating sensory profiles of the Sauvignon Blanc wines to create a lexicon for the use of winemakers.  The Marlborough Wine Research Institute has led trials aimed at understanding the development and concentration of the flavour compounds in fruit, juice and wine.

Similarly, Lincoln University has also carried out work on Sauvignon Blanc flavour compounds.  There are two key groups of compounds that have been found to contribute to the aroma and flavour of the NZ Sauvignon Blanc wines. These are known as “thiols” and “methoxypyrazines”.

Hill Laboratories are able to analyse for these flavour compounds in wine.  The test for thiols covers three different compounds known as 3-MH, 3-MHA and 4-MMP. These compounds have a passionfruit or blackcurrant flavour. They are formed during the winemaking process and are a product of the yeast fermentation.
The methoxypyrazines also covers three compounds known as IPMP, SBMP and IBMP. These compounds are responsible for the green capsicum aroma in wine and have highly potent flavours with a sensory threshold of between 6-15 ppt (parts per trillion). Methoxypyrazine flavours are favourable in wines like Sauvignon Blanc but generally unfavourable in red wines. The compounds are formed in the grapes and are transferred into the wine with winemaking process having little effect on the actual levels in the finished product.

Ref. The Wine Science press, January 2005. University of Auckland.

For further information, see the wine testing page.