4-ethylphenol and 4-ethylguaiacol (4-EP and 4-EG)

4-ethylphenol and 4-ethylguaiacol are products of metobolism by Brettanomyces yeast. 4-ethylphenol is responsible for the ‘sweaty saddle/band-aid’ aroma of red wines when present in high concentration, and is generally regarded as detrimental to wine quality. Analysis of wine in barrels will determine whether this compound has been formed in high concentration during maturation and may indicate the need for changes in how the wine is subsequently handled, including blending options, sterile filtration or sulfur management. These compounds can be analysed separately to the oak flavour compounds where the latter is not required.

How does the analysis work?

The analytical method utilises headspace-solid phase microextraction (HS-SPME) combined with GCMS analysis to only detect these volatile compounds.

How can this analysis assist winemakers?

The analytical results will enable winemakers to determine significant barrel-to-barrel variation in perceived wine quality. Differences may be due to Brettanomyces activity. Analysis of wines during barrel storage may provide information that will enable winemakers to manage sulfur levels and capture early signs of Brettanomyces activity.

Prices per analysis (excluding GST)
Analysis 1-7 samples 8+ samples
4-EP & 4-EG (Brettanomyces) in wine $85 $77
Target response time 10 working days
Volume required Wine: 20 mL
Wood: 50 g

For more information, please contact AWRI Commercial Services on (08) 8313 6600 or e-mail commercialservices@awri.com.au