Viticulture, Vinification and Grape Varieties
Viticulture
The vine as a perennial plant
Viticulture questions test whether you can reason from the vine's annual cycle and the site. Know the sequence: budbreak, flowering, fruit set, veraison, ripening, harvest, leaf fall, dormancy. Each stage is weather-sensitive: frost threatens budbreak, rain and wind disrupt flowering and fruit set, and heat spikes can shut down ripening.
Climate at three scales
Distinguish macroclimate (region), mesoclimate (a single site or slope), and microclimate (the canopy and cluster zone). Useful tools include growing degree days and heat summation, continentality versus maritime influence, Mediterranean climates, and diurnal temperature range. A wide day-night swing slows acid respiration and helps retain aromatics.
Site and vineyard management
Aspect matters: in the Northern Hemisphere an equator-facing slope is warmer; in the Southern Hemisphere the direction reverses. Roughly, every 100 m of altitude is about 0.6 °C cooler and delays ripening by about a week. Soils matter chiefly through drainage, water-holding capacity, and rooting depth, not through mysterious flavours. Know canopy management (leaf removal, shoot thinning, green harvest), trellising, pruning, rootstock and grafting for phylloxera, clonal selection, organic and biodynamic farming, and the legal limits on irrigation in many European appellations.
Traps
Old vines mean lower yields, not automatic quality. Green harvesting cannot fix an unbalanced vine. Diurnal shift and altitude are not the same thing. Terroir includes human choices, so it is not purely geological. Irrigation is restricted rather than universally banned. Frost protection methods (wind machines, sprinklers, candles) address radiation versus advection frost differently.
Worked example
A valley-floor site and a 500 m slope share a latitude. The slope is about 3 °C cooler by altitude but gains warmth from its south aspect and gains UV and diurnal range. Expect later picking, higher acidity, and brighter aromatics from the slope. Rule of thumb: aspect and altitude can offset each other, so always ask which effect dominates.
Vinification and Grape Varieties
From fruit to wine
Know the sequence: sorting, destemming, crushing, pressing, fermentation, maceration, maturation, fining, filtration, bottling. Red wines ferment on skins, so cap management matters: punch down, pump over, rack and return, or submerged cap. Whites are usually pressed before fermentation, but skin contact is a stylistic choice. Free-run wine is lighter; press wine is darker and more tannic.
Fermentation and maturation choices
Alcoholic fermentation converts sugar to ethanol and carbon dioxide; malolactic fermentation converts malic to lactic acid and softens acidity, common in reds and some whites. Temperature control shapes style: reds typically ferment warmer (roughly 25–30 °C) than whites (roughly 12–20 °C). Carbonic maceration uses whole berries under CO2 and yields fruity, low-tannin wines. Maturation options include stainless steel, neutral and new oak, amphora, and lees stirring. New oak adds flavour and tannin; neutral oak mainly allows gentle oxygenation.
Sweet and sparkling specialities
Sweet wines may use late harvest, noble rot, frozen grapes, dried grapes, or fortification. Sparkling wine can be made by the traditional method (second fermentation in bottle, riddling, disgorgement, dosage), the tank method, the ancestral method, or transfer.
Grape variety logic
Think in terms of skin thickness, acidity, tannin, and aromatic intensity: thin-skinned Pinot Noir and Gamay versus thick-skinned Cabernet Sauvignon and Mourvèdre; aromatic Riesling, Muscat, and Gewürztraminer; high-acid Chenin Blanc and Sauvignon Blanc.
Traps
Malolactic is not mandatory for whites. Residual sugar is not the same as perceived sweetness. Carbonic wines are not simply “unfermented.” Press wine is not superior to free-run. Oak flavour comes mainly from new barrels, not from time in wood alone.
Worked example
One tonne of grapes yields roughly 150 gallons, about two 60-gallon barrels, or roughly 60 cases of 12 bottles. Use this to sanity-check production-cost questions.