New World Strategies for Winemaking with Blanc Du Bois and Lenoir

1. Michael Sipowicz Texas Custom Wine Works mike@texascww.com New World Strategies for Winemaking with Blanc Du Bois and Lenoir

2. What we will cover…. • Specifics regarding each variety • Generalities which apply to a broader group

3. Blanc du Bois • Central Florida Research and Education Center in 1968 • Released 1987 (Mortensen 1987) • Little is known about the flavor characteristics or volatiles

4. Blanc du Bois A Study of Blanc Du Bois Wine Quality E. Dreyer, Charles Sims, Russell Rouseff, Dennis Gray, and Michael Sipowicz Am. J. Enol. Vitic. 64:1 (2013) • The objective of this study determine: • Sensory characteristics • Flavor volatiles • Chemical parameters • Relationships between these • Large, representative sample of Blanc Du Bois wines evaluated

5. Blanc du Bois A Study of Blanc Du Bois Wine Quality E. Dreyer, Charles Sims, Russell Rouseff, Dennis Gray, and Michael Sipowicz Am. J. Enol. Vitic. 64:1 (2013) • Seventeen different wines • 100% Blanc du Bois • Vintages 2006, 2007 & 2008

6. Blanc du Bois A Study of Blanc Du Bois Wine Quality E. Dreyer, Charles Sims, Russell Rouseff, Dennis Gray, and Michael Sipowicz Am. J. Enol. Vitic. 64:1 (2013) • Wine Quality Evaluation • Florida State Fair 21st Annual Wine and Grape Juice Competition in 2009. • Evaluated by 26 experienced judges • Descriptive Analysis • 16 Trained panelist • Chemical Analysis • six replications for each wine

7. Blanc du Bois Principal component analysis (PCA) was run to help visualize differences among the wines and how quality might be influenced by those differences. There are two general categories under which these Blanc Du Bois wines fall

8. Blanc du Bois • Wines 9, 13-highest for phenolic/rubber • Wines 9, 12, and 13-highest means for bitter and greenwood/stemmy character intensity. • Sweetest wines (6, 7) had greater than 4% residual sugar, grouped with sweet and honey attributes. • Wines 2 and 3 appeared to be heavily influenced by their titratable acidities and high citrus character • Three other high quality wines (1, 4, 5) grouped with the sweet, fruity, and floral attributes and opposite the greenwood/stemmy and phenolic/rubber attributes. Figure 2: PCA samples plot showing PC1 and PC2 for the DA attribute intensity data. Numbers indicate quality ranking of the wine, with 1 being highest quality.

9. Blanc du Bois Wines tended to have one of two flavor profiles: • Citrusy, bitter, and greenwood/stemmy wines • Contrast with wines possessing sweet, fruity, and floral attributes • Wines perceived as higher quality aligned with later group attributes

10. Blanc du Bois Correlation Analysis: • wine quality was positively correlated with peach and rose • negatively correlated with greenwood/stemmy, phenolic/rubber, bitter, • Strong correlation to Grapefruit & Lemon • The only volatile to correlate negatively with quality (p<0.10) was furfural

11. Blanc du Bois Furfural: Compounds result from degradation of sugars and carbohydrates by heat (Maillard reactions). *Consider not barrel aging or adding oak

12. Blanc du Bois

13. Put your best foot forward… Maximize: Fruity Aromatics Overripe Honey Minimize: Stemmy & Green Oaky Phenolic Rubber Bitter

14. Thiols • Yeast derived… • passion fruit, boxwood, grapefruit, cat pee and similar things favored in Sauvignon Blanc

15. Terpenes • Fruit derived… • Bound with glucose. Sweet and floral to resinous and herbaceous

16. Terpenes • Fruit derived… • Must be liberated. • Bottle aging (hydrolysis) – Accelerated with increase in temperature • Glycosidase Enzyme Treatment

17. Who’s YOUR Daddy?

18. Blanc du Bois • Use of pecticenzymes vs. bentonite for juice clarification • Proper pre-fermentation nutrient additions • Use bentonite in the fermentor for grape lots which have historically high post-fermentation stability requirements • Use of post-fermentation pectic (glycosidase) enzymes(Zoecklein, 2003)

19. Blanc du Bois Use of pectic enzymes vs. bentonite for juice clarification • Most commercial pectic enzymes have some level of glycosidases, the enzymes that can break the glycosidic bond, releasing bound aroma/flavor components +++ • Glycosidases are capable of releasing aromatic terpenols from their non-aromatic precursors +++ • Bentonite can adsorb large concentrations of ethyl and acetate esters, thus lowering aroma and aroma intensity - (Zoecklein 2003, Lourens et al. 2000)

20. Blanc du Bois Use of pectic enzymes vs. bentonite for juice clarification • Glycosidases are generally inhibited by small concentrations of glucose • Pre-fermentation aroma/flavor evolution will be minimal • Enzyme formulation will facilitate clarification of juice without the use of bentonite, with some aroma/flavor evolution potential(Lourens et al. 2000)

21. Blanc du Bois Proper pre-fermentation nutrient additions • Too much DAP can lower the production of esters • Nutrient deficiencies during fermentation can lead to unhealthy / stuck fermentation • Off flavors / aromas (Zoecklein, 2003)

22. Blanc du Bois Use bentonite in the fermentor for grapes which have historically high post-fermentation stability requirements (>2 lb/1000gals) • Bentonite can adsorb large concentrations of ethyl and acetate esters, thus lowering aroma and aroma intensity • Fermentation with bentonite requires the addition of fermentable nitrogen. • Bentonite use during fermentation will reduce (eliminate?) bentonite requirements post-fermentation (Zoecklein et al., 1995, 1999)

23. Blanc du Bois Use of post-fermentation pectic (glycosidase) enzymes • Some suggest that an enzyme should only used on part of a final blend as it is not desired that all the bound flavors are released into the volatile form • Monoterpenes are fairly stable molecules and are hydrolyzed over time, releasing a floral aroma over a long period of ageing. • Enzyme activity will release a lot of flavor/aromatics all at once. • By treating only a part of a blend, the rest of the blend will supply the flavors to enhance the longevity of the wine. (Zoecklein, 2003 & Lourens et al. 2000)

24. Blanc du Bois Use of post-fermentation pectic (glycosidase) enzymes • Can be added to a finished wine or a wine with a residual sugar of 50 g/L or less • The enzyme action must be stopped after one to four months depending on the desired effect that is required. The enzymes have to be removed with .4 -.8 Lbs/1000 gallons bentonite, or by precipitation with tannin phenols (preferred) • Bentonite can adsorb large concentrations of ethyl and acetate esters, thus lowering aroma and aroma intensity (Zoecklein, 2003 & Lourens et al. 2000)

25. Blanc du Bois Use of post-fermentation pectic (glycosidase) enzymes • Not inhibited by the alcohol content of table wines • Much success with varieties such as Muscat, Gewürztraminer and Riesling • Sauvignon blanc and Chardonnay contain monoterpenes in addition to their specific varietal character. It is not always desirable for these grape varieties to have a terpene background aroma so glycosidase enzymes should be used carefully on these varieties (Lourens et al. 2000)

26. Who’s YOUR Daddy?

27. Improve Acid StructureIn the Winery Perception of Acidity - SUGAR + TANNINS + HERBACIOUSNESS, MP’s - POLYSACCHARIDES + INTENSITY OF TANNINS + BITTER / DRYING / ASTRINGENT

28. Improve Acid StructureIn the Winery Perception of Acidity

29. Improve Tannin StructureIn the Winery • Speed of Processing • Skin Contact WHITES- Atypical Phenolic Profile Astringency, Bitterness, Drying NZ “Kiwi” Style Sauvignon Blanc --Likely NOT Possible Utilizing Current Transport  Crush Protocols

30. Improve Tannin StructureIn the Winery • Length of Contact With Skins • Equal Opportunity Extraction • Transport ,Fermentation & Maceration • Subjective Sugar, Polysaccharides, Body, Color, Aromas vs. Bitterness, Drying, Tannins

31. Improve Tannin StructureIn the Winery Perception of Phenols + ACID + HERBACIOUSNESS, MP’s - POLYSACCHARIDES, OTHER SUGARS + INTENSITY OF TANNINS + BITTER / DRYING / ASTRINGENT - ETHANOL (Up to 14%, + Above 14%) + VOLATILE SULFUR COMPOUNDS

32. Improve Tannin StructureIn the Winery Perception of Phenols

33. Varietal TraitsIn the Winery Proper pre-fermentation nutrient additions • Too much DAP can lower the production of esters • Nutrient deficiencies during fermentation can lead to unhealthy / stuck fermentation • Off flavors / aromas (Zoecklein, 2003)

34. Varietal TraitsIn the Winery • MOG (materials other than grapes) removal & Stem separation • Properly functioning destemmer • Leaves in the fermenter can be a source of herbal character • Sensory differences dramatic between wines made with and without jack stem removal • Post-destemmer sorting tables

35. Varietal TraitsIn the Winery • Sort/Cull as much rot as possible. • An incidence level of only 1-3% can negatively influence quality depending on the extent and nature of the rot. • Larger yeast inoculation • High incidences of fungal degradation influence must nitrogen and micronutrients • Test pre-fermentation nutrient levels and adjust accordingly(Zoecklein, 1997)

36. Varietal TraitsIn the Winery • Consider whole cluster pressing whites vs crush and drain. Press lightly or segregate. • Cold settle using pectic enzymes and PVPP. The enzymes will help lower the non-soluble solids level. • The PVPP will help to bind some of the harsh, low molecular weight phenols which have been extracted due to the rot. Use up to 4 pounds/1000 gal PVPP (Zoecklein, 1997)

37. Varietal TraitsIn the Winery • Consider Hyper-oxygenation (Hyper-Ox) • Add ~15ppm Free SO2 (Reserves some O2 for Healthy Fermentation) • “Rake” Pan as Juice is Pressed Out • or • Bubble air into receiving tank

38. Varietal TraitsIn the Winery • Consider Hyper-oxygenation (Hyper-Ox) • Juice will “Brown Out” • PPO will React with Phenols • Leads to polymerization and Precipitation of Phenolics that contribute to Bitterness • Oxygen is a limiting factor in reaction • Don’t Over do it….Can lead to LOSS of aromatics • 9mg/L O2 per Liter of Juice

39. Varietal TraitsIn the Winery ….BALANCE

40. WHAT IS Lenoir ANYWAY? Lenoir • Very Old Wine Grape Variety • Heritage Unknown • Believed to be a V. aestivalis / V. viniferahybrid

41. …A bad Rap! • By many is considered Inferior to more mainstream European Varieties due to an Atypical Aromatic/Flavor Profile • Influenced by Production Practices?

42. …A bad Rap! Issues • Color stability • “Odd” or “Off” flavor • “Animal” or Vinyl Phenol Aromas • Poor structure

43. WHAT WE CURRENTLY KNOW Based On: • Years of Winemaker’s Experience • Anecdotal Evidence • Numerous Sensory Trials

44. WHAT WE CURRENTLY KNOW Aroma / Flavor Trait Appears to be Affected By: • Fermentation Temperature • pH • Yeast and as Well Malolactic Bacteria Strains • Presence of Other Grape Varieties • Some Suspicion That Vinylphenols Involved

45. PLAN OF ACTION • Controlled Environment • Lab Fermentation Trials--Common Red Winemaking Protocols • Find Correlations • Sensory Evaluation and Analysis • Recommendations

46. FERMENTATION TRIALS

47. FERMENTATION TRIALS • Warm Lots Fermented • 90-95ºF • Cool Lots Fermented • 75-80ºF

48. FERMENTATION TRIALS -WARM FERMS

49. FERMENTATION TRIALS- COOL FERMS

50. PRELIMINARY FINDINGS -2010 • COLOR