Wine Study Guide

📖 Core Concepts Wine – fermented grape juice (or other fruit for fruit wines); 13 % ABV on average. Residual Sugar – sugar left after fermentation; determines dry (little) vs sweet (high) wines. Aging – proper storage (12‑13 °C, 65‑70 % RH) can improve flavor; improper light/heat degrades it. Terroir – the combined effect of climate, soil, slope, elevation, and human practices on a wine’s character. Vinification – the winemaking chain: harvest → crush/press → primary fermentation → (optional) malolactic fermentation → aging → filtration/ sulfiting → bottling. Classification – Varietal (one dominant grape) vs Blended; geographic systems (AOP/DO‑C/PGI/PDO in Europe, AVA in New World). Vintage – the year the grapes were harvested; vintage quality hinges on seasonal weather. --- 📌 Must Remember Alcohol content typical: ≈13 % ABV. Dry table wines = low residual sugar; dessert wines = high residual sugar (noble rot, icewine, Vin Santo). Sparkling = secondary fermentation → CO₂; Traditional (Champagne, Cava) vs Charmat (Prosecco, Asti). Phylloxera crisis → graft European V. vinifera onto American rootstock (still used). Appellation laws began in France, 1947; now worldwide (PGI, PDO). Latitude for viticulture: 30°–50° N or S. Malolactic fermentation softens harsh malic acid → lactic acid. Legs/tears on glass → indicator of high alcohol or sugar. --- 🔄 Key Processes Harvesting – pick when sugar (°Brix) & acid meet style target; hand or machine. Crushing & Pressing – destem, crush; brief maceration for reds, immediate press for whites. Primary Fermentation – yeast (natural or selected) converts sugars → alcohol + CO₂ + heat. Red‑Wine Specifics – pump‑overs or punch‑downs to extract tannins & color. Malolactic Fermentation – lactic bacteria convert malic → lactic acid (optional). Secondary Fermentation (Sparkling) Traditional: base wine bottled with yeast & sugar; ages on lees. Charmat: tank fermentation; shorter contact, fruit‑forward. Additions – chaptalization (add sugar), acid adjustments (if permitted). Filtration & Sulfiting – remove microbes; add sulfites for preservation. Aging & Bottling – oak, steel, or concrete vessels; then filter & bottle. Decanting – pour off sediment & aerate young reds. --- 🔍 Key Comparisons Dry vs. Dessert Wine – low residual sugar vs. high residual sugar (noble rot, ice, drying). Traditional vs. Charmat Sparkling – lees aging & complexity vs. quick tank fermentation & fruitiness. Varietal vs. Blended – single‑grape dominant label vs. multiple grapes blended for balance. European (AOP/DO‑C) vs. New World (AVA) – strict geographic & varietal rules vs. broader regional indications. Red vs. Rosé Production – long skin contact for reds; short maceration or blending for rosés. --- ⚠️ Common Misunderstandings “Dry” ≠ no sugar – dry wines still contain small residual sugar; perception is about lack of sweetness. All reds undergo malolactic – many reds skip it to retain acidity. Aging always improves – only suitable wines and proper conditions; many wines decline after peak. Corked wine = cork defect – “corked” can also refer to oxidation or off‑flavors, not just cork material. Higher temperature = better aroma – >20 °C evaporates alcohol and can mask delicate aromas. --- 🧠 Mental Models / Intuition Terroir = “Wine’s DNA” – think of climate, soil, slope as the genetic code that gives each region its signature. Fermentation = Sugar → Alcohol + CO₂ – like baking bread, but the CO₂ stays dissolved (still) or is captured (sparkling). Malolactic = “Acid softening” – swapping a sharp lemon (malic) for a smoother milk (lactic). Legs = “Alcohol‑sugar fingerprint” – thicker legs = higher ABV or sugar. --- 🚩 Exceptions & Edge Cases Outside 30°‑50° latitude – high‑altitude vineyards (e.g., Andes) can ripen grapes despite latitude. Chaptalization – permitted in some cool‑climate regions to boost alcohol; illegal in many warm regions. Non‑vintage blends – common in Champagne, Port, Sherry, Madeira to maintain consistent style. Closure choices – screw caps reduce cork‑taint risk; natural cork preferred for certain premium wines. --- 📍 When to Use Which Sparkling method – choose Traditional for prestige, complexity; Charmat for fresh, fruit‑forward styles. Decanting – use for young, tannic reds or wines with sediment; skip for delicate whites/rosés. Storage – keep bottles at 12‑13 °C with 65‑70 % RH; horizontal for cork, upright for screw‑cap. Classification reference – use EU PGI/PDO for European wines; AVA for New World labeling. --- 👀 Patterns to Recognize Legs on glass → high alcohol or residual sugar. Color + skin time – deep red = long maceration; pale pink = short maceration (rosé). Warm, sunny vintage → ripe, high‑alcohol wines; cool, wet vintage → higher acidity, lower alcohol. Aromatic intensity rises with temperature up to 20 °C, then fades as alcohol evaporates. --- 🗂️ Exam Traps “Corked” answer choice – may refer to oxidation, not necessarily cork‑taint. Assuming all sparkling wines are Champagne – only wines from Champagne region may use the name. Confusing PGI with PDO – PDO (or AOP) is stricter, protecting origin and production methods; PGI is broader. Mistaking “dry” for “no sugar” – dry wines still have residual sugar; the term describes perceived sweetness. Believing every red wine undergoes malolactic – many are bottled before malolactic to retain crispness. ---