The Epistemic Dictionary
Demystifying wine terminology. Every concept is mapped directly to its underlying biological mechanism, chemical pathway, and sensory consequence.
Terroir
Terroir (from Old French 'terrier', earth/land)The complete, immutable sensory signature imparted to a wine by its physical ecosystem: climate, macro/micro-topography, geology, soil microbiology, and cultural viticultural tradition.
Soil water drainage dynamics, mineral cation exchange capacity (calcium, potassium, iron), solar radiation reflection, and native microbiota (indigenous yeasts and mycorrhizae) directly regulate vine stress and metabolite synthesis.
Climat
Climat (Burgundian specific)A precisely delimited, named vineyard plot in Burgundy with a unique geological, microclimatic, and cultural history, officially recognized under AOC law and UNESCO heritage.
Micro-faults in Jurassic limestone create distinct combinations of Argovian, Bathonian, and Bajocian marls within parcels separated by mere meters.
Malolactic Fermentation (MLF)
Fermentation Malolactique (FML)A secondary bacterial enzymatic conversion where lactic acid bacteria decarboxylate sharp dicarboxylic malic acid into softer, creamier monocarboxylic lactic acid and carbon dioxide.
$\text{HOOC-CH}_2\text{-CH(OH)-COOH (Malic Acid)} \xrightarrow{\text{Oenococcus oeni}} \text{CH}_3\text{-CH(OH)-COOH (Lactic Acid)} + \text{CO}_2$. Releases diacetyl as a metabolic byproduct.
Bâtonnage (Lees Stirring)
Bâtonnage (from 'bâton', stirring rod)The rhythmic manual or mechanical stirring of dead yeast cells (lees) resting at the bottom of an oak barrel or vat during aging.
Accelerates yeast cell autolysis, liberating mannoproteins, glucans, and amino acids into the wine matrix while consuming dissolved oxygen, preventing premature oxidation.
Sur Lie (On the Lees)
Élevage sur liesAging wine directly in contact with the fine lees (dead yeast cells formed after alcoholic fermentation) without immediate racking.
Yeast cell walls release polysaccharides that bind to bitter polyphenols and stabilize tartrate crystals, creating a natural antioxidant reductive buffer.
Carbonic Maceration
Macération CarboniqueAn anaerobic vinification technique where intact, uncrushed whole grape clusters ferment inside an oxygen-free, $\text{CO}_2$-saturated tank via intracellular enzymatic fermentation before traditional yeast takes over.
Grape enzymes convert sugars to alcohol (up to ~2-3% ABV) inside intact berries without yeast, breaking down malic acid and synthesizing high levels of volatile esters (isoamyl acetate).
Noble Rot (Botrytis cinerea)
Pourriture Noble / EdelfäuleA beneficial fungal infection of ripe grape berries by the necrotrophic fungus Botrytis cinerea under humid morning mists and dry, sunny afternoons.
Fungal hyphae puncture microscopic pores in grape skins. Afternoon sunshine evaporates water, concentrating sugars, tartaric acid, and minerals, while the fungus synthesizes gluconic acid and glycerol and degrades malic acid.
Dosage (Liqueur d'Expédition)
Liqueur de DosageThe final addition of still wine and cane sugar (liqueur d'expédition) to a bottle of traditional method sparkling wine immediately following disgorgement to establish the final sweetness category.
Buffers the razor-sharp natural malic/tartaric acidity (often $\text{TA} > 8.0\text{ g/L}$) and balances sensory CO2 pressure.
Disgorgement (Dégorgement)
Dégorgement à la glaceThe process in traditional method sparkling winemaking of freezing the bottle neck and ejecting the collected plug of dead yeast sediment (lees).
Bottles are riddled (remuage) neck-down; freezing in brine at $-27^{\circ}\text{C}$ creates an ice plug containing the sediment. Uncapping allows internal 6-bar pressure to violently expel the plug with minimal liquid loss.
Brettanomyces (Brett)
Brettanomyces bruxellensisA non-spore-forming spoilage yeast capable of metabolizing residual pentose sugars and cellobiose in oak barrels and unhygienic cellars, synthesizing volatile phenols.
Decarboxylates and reduces grape hydroxycinnamic acids into 4-ethylphenol (4-EP) and 4-ethylguaiacol (4-EG).