Maturation Flashcards
What is the definition of maturation (élevage) in winemaking?
The period of time post fermentation which is used to bring a newly fermented wine closer to target wine style.
What are the primary focuses of wine maturation?
Altering the organoleptic properties of the wine and influencing microbial status, chemical stability, and physical clarification.
List the organoleptic characteristics impacted by maturation.
- Visual: Clarity and colour
- Aroma & Flavour: Types, positive and negative characters, and intensity
- Taste: Acidity, bitterness, sweetness, and umami
- Touch: Carbonation, astringency, mouthfeel, and weight
What key mechanisms drive changes during maturation?
- Autolysis
- Barrels & Dissolution of Oak Compounds
- Addition of Fining Agents
- Anaerobic and Aerobic Reactions
What is autolysis in the context of winemaking?
Breakdown of yeast and bacteria leading to the release of various compounds.
What factors influence autolysis?
- Enzymes (Lytic enzymes, lysozyme, Glucanases)
- Biomass quantity
- Microbiological species and strains
- Ethanol content
- Temperature
- Sulphite
- Physical activity
- Oxygen
What are the impacts of autolysis on wine?
Changes in ester content, higher alcohols, thiols and other sulphur compounds, and polysaccharide content affecting astringency and mouthfeel.
What roles do barrels play in wine maturation?
- Lees contact
- Oxygenation
- Evaporation
- Dissolution of oak compounds
Name the traditional oak sources used in winemaking.
- Quercus alba (American oak)
- Quercus robur (French/English oak)
- Quercus petraea/sessiliflora (Irish/Welsh/Cornish oak)
What types of compounds does oak contribute to wine?
- Non-volatile: Gallotannins, Ellagitannins, Coumarins
- Volatile: Oak lactones, Volatile phenols, Benzoic aldehydes, Furanic aldehydes
List some alternative vessels that can be used for maturation.
- Stainless Steel
- Concrete
- Pottery/Terracotta
- Plastic
- Ceramic
What are fining agents used for in winemaking?
To improve clarification and stability, and to alter organoleptic properties.
What main reactions occur in wine during maturation?
- Polyphenol reactions (tannin condensation, tannin polymerisation, anthocyanin loss)
- Aroma reactions (esterification, ethanal formation, acetic acid formation)
True or False: Maturation is a critical stage in winemaking that impacts the final wine style.
True
Fill in the blank: Maturation influences microbial status, _______ stability, and physical clarification.
[chemical]
What are the next steps suggested for further research in wine maturation?
- Further research into specific autolysis enzymes and their impact on wine flavour
- Investigation into the legal regulations surrounding the use of oak alternatives
- Detailed study of polyphenol reactions during maturation and their effect on colour and stability.
