Industrial scale fining influences the aroma and sensory profile of Sauvignon blanc

- Juice fining can influence the aroma profiles of press fraction wines.
- Activated carbon juice fining leads to decreases in varietal wine thiols.
- Gelatin juice fining may lead to a rise in ethyl (dihydro)cinnamate levels.

Press fraction juice is generally considered to be of a lower quality than free run and due to excess skin and oxygen contact may result in wines with harsh phenolic profiles. In this situation, fining agents may be used to aid the removal of certain polyphenols. During this study, commercial fining agents were employed to fine two sets of Marlborough press fraction juice in industrial sized trials. The concentrations of 23 aroma compounds were determined for the resulting experimental wines, along with a simple sensory analysis. Results showed that both juice and fining agent choice had the ability to influence the wines aroma chemistry. For instance, the Wairau valley juices fined with activated carbon gave an average 3-mercaptohexanol level of 262 ng/L, less than the corresponding control (415 ng/L) which received no fining agent addition. 3-Mercaptohexyl acetate was also lower in these activated samples at an average level of 180 ng/L, compared to 268 ng/L for the control. Reductions of linalool and β-citronellol by activated carbon fining were also observed during this trial. Ethyl (dihydro)cinnamate increased with the use of gelatin from 0.51 and 0.42 μg/L in the control wines to 1.18 and 1.38 μg/L for each juice set, respectively.