Vineyard and grape exposure to smoke may result in wines with undesirable sensory characteristics such as smoky, burnt, bacon, medicinal or ash along with ‘ashtray’, and bitter aftertaste. 

Molecules responsible of smoke character in wine: Numerous volatile phenols are present in bushfire smoke and can be absorbed by grape berries and vine leaves during a smoke event. The primary compounds in smoke responsible for taint are free volatile phenols (guaiacol, 4-methylguaiacol, o-cresol, p-cresol, m-cresol, etc) which are produced and released into the atmosphere when lignin in wood is burnt. After veraison, a heavy smoke exposure, as short as few hours, can impact grapes and wine expression.

10 TIPS TO MITIGATE SMOKE CHARACTERS – WHITE & ROSE WINEMAKING

1. Hand harvest, sort out leaf material and remove any ashes present on grapes.

2. Limit SO2 use to reduce extraction of unwanted compounds and use Excellence BioNature, non-Saccharomyces, non-fermentative yeast, used for microbial control on grapes. Simply, sprinkle it on grapes at picking or processing, 50 g/ton.

3. Whole cluster press and press gentle to limit extraction. Press program should allow a slow increase in pressure with minimum rotations (Cremant cycle). Press fractions separation: press cut to be decided by tasting.

4. Promote strong clarification, elimination of lees and fining juice to have start with a ‘clean’ base the fermentation. Add Oenozym Clar (clarification enzyme, purified of cinnamyl esterase to limit production of volatile phenols) at 2-4 ml/hL in the press pan and Polymix Natur’ (PVPP, yeast protein extract, bentonite) to improve settling, remove oxidized and oxidable phenolic compounds and some off-aromas.

5. Select a yeast strain with good aromatic production and high production of mannoproteins to balance ‘ashy’ and drying mouthfeel = > Excellence TXL.

6. Rehydrate yeast with OenoStim at 25 g/hL to improve its resistance, its metabolism and compensate the strong clarification.

7. Promote production of fruity and fresh aromas through yeast nutrition: 20 g/hL of OptiEsters during the first 1/3 of fermentation.

8. Use mannoproteins during fermentation to build mid-palate and balance mouthfeel. Natur’Soft, 10-30 g/hL is a yeast derivate rich in mannoproteins used to soften mouthfeel and balance any ‘ashy’ aftertaste.

9. Rack off fermentation gross lees as off-smoke aromas tend to bind to solids and settle.

10. Finishing trials pre-bottling: Subli’Sense (mannoprotein/Arabic gum) showed impressive results in reduce the ‘ashy’ and bitter aftertaste due to smoke events. We can help you setting up bench trials. Market for early release: smoke-related characteristics can evolve in bottle as wine ages.

10 TIPS TO MITIGATE SMOKE CHARACTERS – RED WINEMAKING

1. Hand harvest, sort out leaf material and remove any ashes present on grapes

2. Limit SO2 use to reduce extraction of unwanted compounds and use Excellence BioNature, non-Saccharomyces, non-fermentative yeast, used for microbial control on grapes. Excellence BioNature can be directly sprinkled on grapes at picking or processing, 50 g/ton.

3. Select a strong fermenter yeast strain with high production of mannoproteins to balance ‘ashy’ and drying mouthfeel = > Excellence DS

4. Promote production of fruity and fresh aromas through yeast nutrition: 20 g/hL of OptiEsters during the first 1/3 of fermentation.

5. Use tannins and mannoproteins during fermentation to stabilize color, build mid-palate and balance mouthfeel. Softan V is a proanthocyanidic tannin bound to plant polysaccharides, to improve color stabilization in wines with low to medium phenolic content. Addition of 150-200 g/ton at the beginning of fermentation. Natur’Soft is a yeast derivates rich in mannoproteins used to stabilize color, soften mouthfeel and balance any roughness on the finish. Addition of 180-200 g/ton at mid fermentation.

6. Untoasted Oak chips can reduce intensity of smoke characteristics through increased wine complexity.

7. Separate press fractions and treat separate. We have samples of fining agents and can set up fining bench trials for you.

8. Once pressed, promote fast settling and rack off lees early with Oenozym Clar at 2-3mL/hL. Off-aromas bound to lees and can be eliminated by racking early. It is important to choose an enzyme purified of cinnamyl esterase to limit production of volatile phenols.

9. Choose ML bacteria, fast fermenter and producer of esters and acetates: Oeno1. To increase production of fresh and fruity aromas and limit smoky characters, co-inoculation is recommended.

10. Finishing trials pre-bottling: Subli’Sense (mannoprotein/Arabic gum) showed impressive results in reduce the ‘ashy’ and bitter aftertaste due to smoke events. Let us know, we can help you setting up bench trials. Market for early release: smoke-related characteristics can evolve in bottle as wine ages.

https://www.bvnorthamerica.com/news/2020/8/20/10-tips-to-mitigate-smoke-effects-on-wine