Sherry winemaking

Question 1

Sherry winemaking: pressing to ferment

Answer 1

Pressing

• Done as soon as possible after harvest.
• Primera yema (free-run & lightest pressings, 60–75% of juice): used for biologically aged styles.
• Segunda yema (later pressings): for Oloroso – higher phenolics inhibit flor.
• Prensas (final fractions): used to season new casks, then often distilled into spirit.
• Producers (e.g., Fundador) focusing on Oloroso may also use partly free-run juice.
• Maximum yield: 70 L / 100 kg grapes.

Pre-Fermentation Extraction

• No extraction techniques used – skin contact avoided (especially for biological ageing).
• Avoiding phenolics important to support flor development.

Must Adjustments

• Acidification may be necessary – Palomino loses acidity late in ripening.

Must Clarification

• Methods: sedimentation, centrifugation, flotation.
• Removes dust and particles from albariza soils – crucial for clean ferment.

Fermentation

• Fermented separately by vineyard – allows diverse blending options pre-fortification.
• Sweet wines: ferment stops naturally at 4–6% ABV due to high sugar, then fortified to 15–16%.
• Cultured yeast widely used – ensures complete fermentation.
• Fermentation temp: 22–26°C – encourages full ferment (varietal aromas not focus).
• Vessels: mostly stainless steel, some old oak barrels used for fuller-bodied base wines.
• First phase: rapid fermentation (most sugar in \~7 days).
• Second phase: slower, takes a couple more weeks (alcohol slows yeast).
• Malolactic fermentation: does not occur – low acidity & low malic acid in Palomino.

Question 2

Sherry Fortification: Timing and type of spirit

Answer 2

Post-Fermentation: First Classification

• Based on tasting and analysis after fermentation.
• Lighter, more delicate wines → marked for biological ageing.
• Fuller, more intense wines → marked for oxidative ageing.

Fortification

• Biological ageing: fortified to 15–15.5% abv – ideal for flor development.
• Oxidative ageing: fortified to 17% abv – flor cannot survive.
• Spirit used: neutral grape spirit at 95% abv (no added aromas/flavours).

Regulatory Update

• 2021 regulation allows base wines naturally at 15% abv to remain unfortified for biological ageing (awaiting EU approval).

Question 3

Sherry - after fortification (2nd class.) + bodegas

Answer 3

Here’s your content condensed into clear bullet points with no loss of information:

After Fortification: Sobretablas Stage

• Wine stored in stainless steel (SS) or wooden butts (pre-solera).
• At this point: still single vintage and fresh.

Second Classification (for biological ageing wines)

• Takes place after a few months of ageing.
• If full flor & fresh → destined for Fino or Manzanilla solera.
• If less delicate or shows development → may go to:
  • Amontillado solera (after prolonged biological ageing).
  • Palo Cortado (switch to oxidative ageing).

Oloroso

• Fuller wines go straight to Oloroso solera after sobretablas.

Ageing Vessels & Environment

• Butts: typically 600 L American oak (old wood preferred to avoid new oak flavors).
• Biological ageing: butts filled to \~500 L to leave headspace for flor.

Bodega Design for Ageing

• Thick walls: help maintain steady temps.
• Tall buildings: warm air rises away from barrels.
• Small high windows: allow in cool, humid Poniente winds.
• Thin blinds: diffuse light, keep out dust/insects.
• Earthen floors: wetted in summer to reduce temperature and increase humidity.

Climate Control in Bodegas

• Humidity & temp control critical for flor growth & maintenance.
• Some seasonal variation (summer vs. winter), but relatively stable environment.

Question 4

Sherry maturation method

Answer 4

Sweet Sherry

• Aged in its own solera system.
• Gradual evaporation leads to concentration of sugar and flavour.

Solera System Overview

• Fractional blending and maturation system.
• Ensures non-vintage (NV) Sherry has consistent quality and style.

Structure: Criaderas and Solera

• Barrels grouped by age of wine they contain:
  • Solera: oldest level.
  • 1st Criadera: second oldest.
  • 2nd Criadera: younger still, and so on.
• Typically 3–4 to 12+ criaderas.
  • More criaderas = longer ageing, greater complexity, higher price.

Wine Movement & Flexibility

• Wine does not always pass through every level.
  • Younger release styles: may be drawn earlier (cheaper wines).
• Example Blends:
  • Inexpensive Fino: wine mainly from 4th + 5th criaderas, touch of 1st for complexity.
  • Premium/Mid-priced: mostly solera + 1st criadera, little 4th for freshness.

Solera Process

1. Portion drawn from solera level for bottling.
2. Equal volume from 1st criadera blended in tank.
3. Solera butts topped up from this tank blend.
4. Repeat up through criaderas:
   • 2nd → 1st
   • 3rd → 2nd, etc.
5. Youngest wine (from sobretablas) added to top criadera.

Question 5

Sherry solera - legal regulations

Answer 5

Legal Regulations

• Max 40% of any solera system can be drawn off per year.
• Ensures continuity and aging base.
• Minimum age for any Sherry sold: 2 years.

DO Jerez-Xérès-Sherry
* before 2011: within 3 municipalities (Zona de Crianza): Jerez de la Frontera, El Puerto de Santa María or Sanlúcar de Barrameda
* after 2011: anywhere in Production Zone
DO Manzanilla - must be in municipality of Sanlúcar de Barrameda.

Question 6

Flor: description, effects on wine

Answer 6

Biological Ageing (Flor Yeast Maturation)

• Involves maturation of wine under a layer of flor yeast.
• Flor = 4 strains of Saccharomyces cerevisiae.
  • Found on grape skins and within bodegas.
  • Strain proportions vary:
    • By location, bodega, and even stage within solera system.
    • Affects alcohol consumption rate + acetaldehyde production.

Flor Formation & Growth Requirements

• Forms on surface of young wines at up to 15.5% abv.
  • Struggles above 16% abv.
• No SO₂ added – would inhibit flor development.
• Requires plentiful oxygen:
  • Butts filled only to 85–90%.
  • Bungs loosely inserted.
• Key conditions:
  • Temp: 16–20°C.
  • Humidity: above 65%.

Flor Impact on Wine

• Protects wine from oxidation:
  • Wine remains pale lemon in colour.
• Consumes alcohol.
• Releases acetaldehyde:
  • Flavours: apple, bruised apple, apple skin, hay, chamomile.
  • Adds a slightly bitter character.
• Consumes glycerol:
  • Glycerol contributes sweetness and body.
  • Result: lighter body, drier mouthfeel.
• Lowers acetic acid (volatile acidity).
• Over time, flor dies and falls, causing autolysis:
  • Adds savoury, nutty notes, and enhances texture.
  • Other aromas from reactions between alcohol, acids, and acetaldehyde: e.g. bread, green apple, cheese.

Sustaining Flor in Solera System

• Solera transfers younger wine to older stages:
  • Replenishes alcohol, glycerol, acetic acid for flor survival.
• Flor development affected by seasonal temperature and humidity variations.
• Evaporation occurs, but:
  • Alcohol consumption by flor exceeds water loss.
  • So alcohol level gradually decreases over time.

Question 7

Fino vs Manzananilla flor differences

Answer 7

Fino and Manzanilla Specifics

• Require frequent replenishment:
  • Smaller, more regular transfers for nutrient refreshment.
• Bottled more frequently to ensure fresh wine at point of sale.
  • Important as Fino/Manzanilla do not improve with age.

Question 8

oxidative ageing - maturing without flor - characteristics

Answer 8

Oxidative Ageing – Key Effects on Wine

• Colour progression:
  • Starts lemon
  • Then gold → amber → brown
• Alcohol increases:
  • Due to evaporation (water evaporates faster than ethanol)
  • Typically 3–5% volume loss per year
  • Leads to concentration of all components
• Aromatic and flavour development:
  • Shifts from primary to tertiary aromas
  • Development of oxidative notes:
    • Caramel, nuts, dried fruit
• Texture and mouthfeel:
  • Glycerol levels rise due to evaporation
    → Results in a fuller, rounder body
• Chemical changes:
  • Acetaldehyde decreases (unlike biological ageing)
  • Acetic acid and ethyl acetate (linked to volatile acidity)
    → Increase slightly over time

Question 9

Considerations for blending regarding Sherry

Answer 9

Sweetened Sherry Production

• Base wine:
  • Can be biologically aged, oxidatively aged, or a blend of both styles.
• Sweetening component:
  • Typically Pedro Ximénez (PX) or other concentrated grape must.
• Timing of sweetening:
  • Before bottling (common for inexpensive styles).
  • Or before entering a solera (used in premium/mid-priced wines).
• Inexpensive Sherry:
  • Typically young wines sweetened just before bottling.
  • Little to no extended ageing post-blending.
• Mid-priced / Premium styles:
  • Use of own solera systems to age sweetened blends.
  • Example:
    • Gonzalez Byass’ Matusalem VORS Cream Sherry:
      • Blend of wines aged 15 years, then aged another 15 years in a solera post-blending.
• Flexibility in solera use:
  • Different solera systems can be:
    • Blended together during final blending.
    • Or, wine from one solera may be transferred to another for further maturation.
  • Example:
    • Amontillado:
      • May spend 5 years in a Fino solera,
      • Then 8 more years in an Amontillado solera.

Question 10

Post-fermentation finishing and packaging
Sherry

Answer 10

Finishing & Packaging of Sherry

• Tartrate stabilization:
  • Most wines are tartrate stabilized using the contact process.
• Fining and filtration:
  • Wines are typically fined and filtered.
  • Filtration is especially important to remove flor yeast:
    • Any remaining flor could re-grow after bottling if the wine is exposed to oxygen (e.g. after opening).
• Closures used:
  • Natural cork
  • Cork stoppers
  • Screw caps
• Legal requirement:
  • All packing and packaging must be done within the three Sherry municipalities:
    • Jerez de la Frontera
    • El Puerto de Santa María
    • Sanlúcar de Barrameda