Viticulture and enology
Viticulture and enology covers how grapes are grown and how must becomes wine. The exam tests cause and effect: which vineyard decision changes ripeness, and which winery decision changes colour, tannin, texture or stability.
Viticulture
- Climate: latitude, altitude, aspect and diurnal range. Cool nights preserve acidity; warm days build sugar and phenolic ripeness.
- Soil: drainage and water-holding capacity matter more than mineral content; mildly stressed vines give smaller, more concentrated berries.
- Canopy: leaf removal and trellising control sunlight, airflow, disease pressure and photosynthesis.
- Yield: pruning and green harvest regulate crop load; very high yields can dilute flavour.
- Vines are grafted onto American rootstocks to resist phylloxera.
Enology
Red wines gain colour and tannin during maceration, with the cap managed by punching down or pumping over. Fermentation temperature controls extraction: cooler for whites and aromatic reds, warmer for structured reds. Malolactic fermentation converts malic acid to lactic acid and softens acidity; it is routine for most reds, optional for Chardonnay, and it is not the secondary fermentation that creates bubbles. Oak adds tannin, toast and slow oxygen; large old barrels give little. Fining and filtration clarify and stabilize.
Worked example
"Deep purple, high tannin, blackberry, vanilla, 14.5% ABV." Reasoning: deep colour plus high tannin indicate long maceration and active cap management; vanilla indicates new small oak; 14.5% indicates ripe, warm-climate fruit. Conclusion: warm-climate Cabernet Sauvignon or Syrah aged in new barriques.
Traps
Malolactic is not the sparkling secondary fermentation. Sweetness comes from residual sugar, not ripe-fruit aroma. Sulphur dioxide is a preservative and antioxidant, not the usual cause of headaches; TCA gives musty, wet-cardboard faults.