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ICV Guideline for Mouthfeel Management. Presentation plan. ICV Guideline for Mouthfeel ManagementThe Sensory Tools : sensory method, database, reference profilesChemical background of ICV sensory descriptorsEnzymes, Yeast, Nutrients and Cap Management :
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1. Winemaking Fermentation Techniques and Mouthfeel: An ICV PerspectiveDominique DELTEIL
3. Presentation plan ICV Guideline for Mouthfeel Management
The Sensory Tools : sensory method, database, reference profiles
Chemical background of ICV sensory descriptors
Enzymes, Yeast, Nutrients and Cap Management : ‘Good Practices’ to manage Mouthfeel Profile
ICV Practical Consulting Testimony for :
Grape ripening
Enzymes,
Yeast,
Nutrients,
Cap Management
6. What is ICV Mouthfeel ? A Quantified Descriptive Sensory Analysis Profile (QDSAP)
With 6 descriptors :
A precise procedure with :
A fixed and measured order
A fixed rhythm, in order to standardize the wine/saliva/mucosis interactions, and therefore improve repeatability
7. The 6 Descriptors of ICV Mouthfeel Profile (Red wines)
9. ICV Mouthfeel of a so-called « round, big, good tannin » or Ultra Premium Red wine
10. ICV Mouthfeel of a so-called « thin, hollow, green tannin » red
11. ICV Mouthfeel of a so-called « tannic, over-extracted » red
12. ICV Mouthfeel of a so-called « Brett- killed great Cab » red
15. ICV Sensory Positionning of Commercial Wines.Ultra Premium Reds. Structured scale with 4 levels. From : Delteil, 2001
18. Foremouth Volume: main compounds involved Ethanol: + (up to 14%vol)
Polysaccharides from grape, yeast, bacteria & oak: +
Sugar: +
Acids, salts: + (until a certain level and according to other elements)
Glycérol ?
(a myth… just a short sweet peak in the mid-palate and a higher dryness in the finish)
Volatile compounds with ripe, sweet smell: + (the portion of those compounds that stays in solution in the wine has a smooth impact on the mouth mucosis).
Sulphur off-flavours: - (the portion of these compounds that stays in solution in the wine has an agressive and « cold » impact to the mouth mucosis).
19. Foremouth Volume: sensory interferences Influence of all the other descriptors:
A physiological influence (the sensation step of ASDQ): for example, a high acidity interferes during the measurement of the Foremouth Volume, usually lowering the sensation (of what we perceive)
A psychological (the translation step of ASDQ): for example, herbaceous mouth aromas pushes to lower the Volume mark, even when the sensation was the same
General trend: Foremouth Volume and Bitterness have a negative correlation (when Volume is high, generally bitterness is low)
20. Acidity: main compounds involved Acids: tartaric, malic, lactic, succinic (+)
Sugar : - -
Tannins (+ or -, depending on their « quality »)
Certain volatile compounds (those that give sulphur, chemical and herbaceous aromas) : + (physiological and psychological reasons)
Certain volatile compounds (those that give ripe, fruity, spicy aromas) : - (physiological and psychological reasons)
Polysaccharides from grape, yeast, bacteria or oak: -
21. Acidity: sensory interferences Influence on all the other mouthfeel descriptors : physiological and psychological reasons
+ or - correlation with Volume
+ correlation with Tannic Intensity
+ correlation with Dryness
+ correlation with Bitterness
22. Tannic Intensity: main compounds involved Grape Tannins and Oak Tannins: +
Acids: +
Sugar : 0
Certain volatile compounds (those that give sulphur, chemical and herbaceous aromas) : + (physiological and psychological reasons)
Certain volatile compounds (those who give ripe, fruity, spicy aromas) : - (physiological and psychological reasons)
Yeast in suspension (wine just stirred): +
Polysaccharides from grape, yeast, bacteria or oak: -
23. Tannic Intensity: sensory interferences Strong influence of Acidity (+), sulphur, chemical and herbaceous aromas (+)
Note again: « + » means the intensity evolves in the same way. They are not necessarily interesting attributes
24. Astringency: main compounds involved Grape Tannins and Oak Tannins: +
Acids: +
Sugar: 0
Sulphur, chemical and herbaceous aromas: +
Certain volatile compounds (those that give ripe, fruity, spicy aromas) : - (physiological and psychological reasons)
Ethanol: - up to 14%vol, + over 14%vol.
Polysaccharides from grape, yeast, bacteria or oak: -
25. Astringency: sensory interferences Strong influence of Acidity (+), sulphur, chemical and herbaceous aromas (+)
Note again: « + » means the intensity evolves in the same way. They are not necessarily interesting attributes
26. Dryness: main compounds involved Ethanol: - until 13%vol, + over 13%vol
Sugar: 0
Grape Tannins and Oak Tannins: +
Acids, mostly malic and acetic: +
Sulphur, chemical and herbaceous aromas (+)
Certain volatile compounds (those who give ripe, fruity, spicy aromas) : - (physiological and psychological reasons)
Yeast in suspension (wine just stirred): +
Polysaccharides from grape, yeast, bacteria or oak: -
27. Dryness: sensory interferences Strong influence of
Acidity (+),
Sulphur, chemical and herbaceous aromas (+)
28. Bitterness: main compounds involved Ethanol: + (amplifies the impact of bitter compounds)
Sugar:-
Grape Tannins and Oak Tannins: +
Acids (mostly the malic acid) : +
Sulphur aromas: ++
Certain volatile compounds (those that give ripe, fruity, spicy aromas) : - (physiological and psychological reasons)
Yeast in suspension (wine just stirred): +
Polysaccharides from grape, yeast, bacteria or oak: -
29. Bitterness: sensory interferences Strong influence of
Acidity: +,
Sulphur, chemical and herbaceous aromas: +
30. Winemaking challenges Analysis of the situation:
High risks of sulphur aromas produced by the yeast because of low nutrients and high osmotic shock: producing dryness and bitterness sensations
High ethanol enhancing dryness and bitterness
Strategy to follow:
Developp and stabilize as much as possible all elements that limit dryness and bitterness: polysaccharides and compounds with ripe aromas
Limit as much as possible the production and stabilization of all agressive (astringency and dryness) and bitter compounds
Explore all possibilities and make consistent choices throughout the process
32. Chardonnay simplified profiles Complete maturity :
Goals to be reached to achieve return on investment on strong enological potential vineyard blocks.
To elaborate higher end wines with foremouth volume, aromatic complexity, good length.
Ability to be fermented and aged in barrel.
Minimum commercial maturity
Goals to be reached for mid range vineyard blocks.
Fruity wines, without agressive mouthfeel.
33. Chardonnay simplified profiles
34. Maceration enzymes: main influences (1) Direct hydrolysis of polysaccharides (pulp and skin): early, greater level of stable macromolecules in the colloidal network, and then more interesting interactions with ripe aromas
Early liberation of the sensorically interesting tannins: the hydrophiles ones. In ripe grapes, they are already integrated in a polysaccharide colloidal matrix: early stabilization in a less sensory aggressive form (medium-length chain)
35. Maceration enzymes main impacts (2) Direct action on limiting sulphur off- flavour production during fermentation: a clear experimental trend (Why? Earlier yeast access to certain nutrients? Early interaction between sulphur compounds and grape polysaccharides?)
Indirect action on sulphur off-flavours and herbaceous aromas: easier and more efficient racking directly after maceration, with good and early elimination of heavy ‘vegetal’ lees
37. Effects of maceration enzymes on mouthfeel profiles in reds. ICV Guideline based on 15 years experimentation and experience
38. Yeast main possible impacts: selected enological yeast variability (1) Better resistance to juice stress (high sugar, very low nutrients, high ethanol)
Less production of sulphur compounds
Less production of VA
Less space left for Brettanomyces and Co developpment at the end of fermentation
Better answer to modern demands
Less SO2 production, giving a better sequence of malolactic directly after alcoholic fermentation
39. Yeast main possible impacts: selected enological yeast variability (2) More mannoprotein produced during active fermentation and during aging with light lees:
Earlier development of a stable wine colloidal network (polysaccharides + pigments + tannins)
More and early interactions with ripe aroma compounds from the grapes and from the yeast (more stable and sweeter aromatic expression)
Better sensory integration of very high ethanol concentration
41. Possible trends between selected yeast in reds. ICV guideline based on 20 years of experiments and experience
42. Yeast Nutrients possible impacts : nutrients containing inactivated yeast Better complete nutrient and yeast membrane status:
Less production of sulphur compounds (because there is no enhancement of amino acid starvation in nitrogen-depleted juices : the opposite of the situation when only ammonia salts are added)
Less production of VA
Release of yeast mannoproteins:
Balance the chemical aromas and dryness due to the assimilation of ammonia salts
Better sensory integration of very high ethanol concentrations
44. Effects of Yeast Nutrients on Mouthfeel profiles in reds. ICV guideline based on 10 years of experiments and experience
52. Early Délestage main impacts (1) More liberation of grape polysaccharides (pulp and skin): early and higher level of stable macromolecules in the colloidal network, and also greater interaction with ripe aromas
Early and intense liberation of the most sensorically interesting tannins: the hydrophilic ones. In ripe grapes, they are already integrated in a polysaccharide colloidal matrix: early stabilization in less sensory agressive forms (medium length chain)
53. Early Délestage main impacts (2) Direct action on limiting sulphur off- flavour production during fermentation: complete yeast stirring, oxygen available for all yeast, physical stripping of early production of H2S
55. Effects of Délestage on Mouthfeel profiles in mediterranean reds. ICV Guideline based on 10 years experimentation and experience
57. Common sense statements A well positioned wine answers its segment standards as soon as released : a minimum drinkability.
The « good to drink starting 2015-2030 » is an ultra small niche position.
58. Common sense statements (2) Ageability is a segmented concept :
mid priced wine from rather high yield vines :
get the maximum quality attributes at release
keep a certain quality level through the whole shelf life
high priced wine from highly concentrated grapes
get an acceptable level of drinkability at release
develop positive attributes through time
60. Sulphur compounds Always interfering with the perception of fruit characters : aromas and flavors
Sulphur off-flavors are forever ! Always changing but still there
« Reduction » never preserves your wine from oxidation and too quick aging.
Big sensory synergy with Atypical Aging
61. Macromolecules Mostly polysaccharides
From grapes
From yeast (while living and during aging on lees)
From bacteria
Some are very chemicaly stable : RGII, mannoproteins, glucans.
Participating in interactions (non classical chemical bindings) with many important compounds. Starting in the grape : ultimate hypothesis for « tannin ripening in the grape »
62. Some winemaking trends to get ageability (1) The sources of grape polysaccharides :
First : ripe pulp
Second : ripe skin
Seeds ?
Get grape and yeast polysaccharides in the juice before or while reactive compounds are extracted and may react too much. The goal : to avoid excessive polymerization of tannins.
Enological enzymes on fresh grapes
Diffusion with little alcohol in reds
Avoid mechanical extraction : favour diffusion of easy to diffuse polysaccharides
63. Some winemaking trends to get ageability (2) Take polysaccharides from yeast as much as possible
While living = choose the right strains
While dead = stirring. Start during active fermentation.
Note : Some strains do not bring interesting « ageability » polysaccharides
Take polysaccharides from MLB. To keep fruit : better effect than some grams of malic acid. Better prevention of AA (atypical aging)