WSET Level 4 Diploma Cheatsheet: Key Topics

Unit Overview

D1 — Wine Production Framework

The Annual Vine Cycle

Understanding the vine’s yearly rhythm is foundational. Each stage presents risks and decision points that directly affect the resulting wine.

1. Dormancy (winter) — vine rests; pruning occurs to set the number of buds and therefore potential yield
2. Budburst (spring) — new shoots emerge; frost is the critical risk at this stage
3. Flowering (late spring) — flowers must be pollinated to form grape clusters; cold or rain causes poor fruit set (coulure and millerandage)
4. Fruit set (early summer) — successful pollination leads to small, hard green berries
5. Véraison (mid-summer) — berries begin to ripen; colour change occurs; sugar accumulates and acidity starts to drop
6. Ripening (late summer-autumn) — sugar levels rise, acidity falls, phenolic compounds (tannins, anthocyanins) develop; the winemaker monitors all three to choose the harvest date
7. Harvest — timing is critical: too early means high acid and unripe tannins; too late means low acid, high sugar, and overripe flavours

Viticulture Factors

Winemaking Process Map

Reception and Pre-Fermentation

• Sorting — removes underripe, damaged, or diseased fruit (optical sorters increasingly common at high-end estates)
• Destemming — separating berries from stems; partial or full depending on style (whole-bunch inclusion adds structure and spice)
• Crushing — breaks skins to release juice; some winemakers use whole-berry fermentation for carbonic maceration effects
• Must adjustments — acidification (warm regions), chaptalization (cool regions), enzyme addition for extraction
• Cold soak — pre-fermentation maceration at low temperature extracts colour and fruit character without harsh tannin (reds)
• Skin contact for whites — brief contact can add texture and aromatic complexity; extended contact produces orange/amber wines

Fermentation

• Yeast selection — commercial (predictable, clean) vs indigenous/wild (complex, terroir-expressive, unpredictable)
• Temperature — cool (12-16°C for whites: preserves fruit, floral aromas) vs warm (25-30°C for reds: promotes extraction)
• Vessel — stainless steel (neutral, temperature control), oak barrel (flavour, micro-oxygenation), concrete egg (thermal stability, gentle movement), clay amphora (ancient method, minimal intervention)
• Cap management (reds) — punch-down (pigeage: gentle extraction), pump-over (remontage: more vigorous), rack-and-return (delestage: significant extraction)
• Duration — short (light, fruity reds) vs extended maceration (tannic, structured reds)

Post-Fermentation

• Pressing — free-run juice vs press wine; press wine adds tannin, colour, and structure to blend
• Malolactic fermentation (MLF) — converts malic acid to lactic acid; standard for reds, optional for whites (adds creaminess, reduces sharpness)
• Racking — moving wine off sediment to clarify and expose to controlled oxygen
• Lees contact / bâtonnage — enriches texture, adds bready/nutty notes; key in Muscadet sur lie, barrel-fermented Chardonnay, Champagne
• Oak maturation — new oak (vanilla, toast, coconut, spice, tannin) vs old oak (gentle oxidation, no flavour addition); French (fine grain, subtle) vs American (wider grain, bolder coconut/dill); barrel size (225L barrique vs 500L demi-muid vs larger: smaller = more oak influence per volume)
• Fining — clarification using bentonite, egg white, casein, PVPP; excessive fining can strip character
• Filtration — removes remaining particles; some producers bottle unfined/unfiltered for fuller texture
• SO2 adjustment — final sulphur dioxide addition for protection against oxidation and microbial spoilage

D2 — Wine Business Framework

Market Analysis Structure

When analysing any wine market or business case, use these five lenses:

Supply factors — production volumes and trends, cost of production (land, labour, materials), vintage variation and its effect on supply consistency, emerging regions entering the market, bulk wine versus bottled wine trade flows.

Demand factors — per capita consumption trends (declining in traditional markets like France and Italy, growing in Asia and Africa), premiumisation (consumers buying less wine but better quality), generational shifts (millennials and Gen Z drinking less but more selectively), health and moderation trends (growth of low/no alcohol wine).

Distribution channels — on-trade (restaurants, bars, hotels: higher margins, brand-building), off-trade (supermarkets, wine shops, online: volume, accessibility), direct-to-consumer (cellar door, wine clubs, e-commerce: highest margin, relationship-building), export markets and the role of importers and distributors.

Regulatory environment — EU wine law (PDO/PGI system, labelling requirements, permitted practices), US TTB regulations (AVA system, varietal labelling rules), excise duty and taxation (varies enormously by country and significantly affects retail price), trade agreements and tariffs.

Trends and disruption — sustainability and environmental certification (organic, biodynamic, carbon-neutral), packaging innovation (bag-in-box, cans, lighter bottles), digital marketing and social media, wine tourism, natural wine movement, climate change adaptation.

Key Business Frameworks

SWOT Analysis — Strengths, Weaknesses, Opportunities, Threats. Use this to evaluate a producer, region, or brand. Be specific: “Strength: established reputation for Pinot Noir quality (e.g. Domaine de la Romanée-Conti commands highest prices for any wine globally)” is much stronger than “Strength: good reputation.”

Porter’s Five Forces — Competitive rivalry, threat of new entrants, threat of substitutes, bargaining power of buyers, bargaining power of suppliers. Use to analyse competitive dynamics in a region or market segment.

The Marketing Mix (4Ps) — Product (style, quality, packaging), Price (positioning, strategy), Place (distribution channels, market selection), Promotion (branding, advertising, PR, social media, wine scores).

Wine Pricing Concepts

• Cost-plus pricing — calculate production cost, add desired margin; common for bulk and entry-level wines
• Market-based pricing — price relative to comparable wines; requires understanding of the competitive set
• Prestige pricing — price signals exclusivity and quality; works for established luxury brands (Bordeaux First Growths, Grand Cru Burgundy)
• En primeur — Bordeaux futures system where wine is sold before bottling; speculative element, influenced by critic scores and vintage reputation
• Auction market — secondary market for fine wine; prices driven by rarity, provenance, critic scores, and collector demand

D3 — Wines of the World Key Regions

Must-Know Appellations by Country

France

• Bordeaux: Médoc (Margaux, Pauillac, Saint-Julien, Saint-Estèphe), Graves/Pessac-Léognan, Saint-Émilion, Pomerol, Sauternes
• Burgundy: Chablis, Côte de Nuits (Gevrey-Chambertin, Vosne-Romanée, Nuits-Saint-Georges), Côte de Beaune (Meursault, Puligny-Montrachet, Beaune, Pommard), Côte Chalonnaise, Mâconnais, Beaujolais (10 Crus)
• Champagne: Montagne de Reims, Vallée de la Marne, Côte des Blancs, Côte des Bar
• Northern Rhône: Hermitage, Côte-Rôtie, Condrieu, Cornas, Saint-Joseph, Crozes-Hermitage
• Southern Rhône: Châteauneuf-du-Pape, Gigondas, Vacqueyras, Lirac, Tavel
• Loire: Muscadet, Anjou-Saumur (Savennières, Quarts de Chaume), Touraine (Vouvray, Chinon), Central Vineyards (Sancerre, Pouilly-Fumé)
• Alsace: Grand Cru system, varietals (Riesling, Gewürztraminer, Pinot Gris, Muscat), Vendange Tardive, Sélection de Grains Nobles

Italy

• Piedmont: Barolo, Barbaresco, Barbera d’Asti, Dolcetto d’Alba, Gavi, Asti
• Tuscany: Chianti Classico, Brunello di Montalcino, Vino Nobile di Montepulciano, Bolgheri (Super Tuscans), Vernaccia di San Gimignano
• Veneto: Valpolicella (Classico, Ripasso, Amarone, Recioto), Soave, Prosecco (Conegliano-Valdobbiadene DOCG)
• Other: Etna DOC, Aglianico (Taurasi), Verdicchio, Vermentino

Spain

• Rioja: ageing system (Joven, Crianza, Reserva, Gran Reserva), sub-zones (Rioja Alta, Rioja Alavesa, Rioja Oriental)
• Ribera del Duero, Priorat, Rías Baixas, Toro, Rueda, Jumilla
• Jerez: Sherry (Fino, Manzanilla, Amontillado, Oloroso, Palo Cortado, PX, Cream)

Germany

• Prädikat system: Kabinett, Spätlese, Auslese, BA, Eiswein, TBA
• VDP classification: Gutswein, Ortswein, Erste Lage, Grosse Lage
• Key regions: Mosel, Rheingau, Pfalz, Nahe, Franken, Baden

New World

• USA: Napa Valley (sub-AVAs: Oakville, Rutherford, Stags Leap District), Sonoma (Russian River Valley, Dry Creek Valley), Willamette Valley (Oregon), Washington State (Columbia Valley, Walla Walla)
• Argentina: Mendoza (sub-regions: Luján de Cuyo, Uco Valley — Gualtallary, Altamira), Salta (Cafayate)
• Chile: Central Valley (Maipo, Rapel — Colchagua/Cachapoal), Casablanca, Leyda, Aconcagua, Biobío
• Australia: Barossa Valley, Eden Valley, Clare Valley, McLaren Vale, Coonawarra, Margaret River, Hunter Valley, Yarra Valley, Tasmania
• New Zealand: Marlborough, Central Otago, Hawke’s Bay, Martinborough, Waipara
• South Africa: Stellenbosch, Swartland, Franschhoek, Constantia, Elgin, Hemel-en-Aarde

Tasting Paper Strategy

The Diploma tasting paper is where many students struggle. Follow this framework rigorously:

1. Appearance — clarity (clear/hazy), intensity (pale/medium/deep), colour (specific: lemon-green, gold, ruby, garnet, tawny). Colour alone can indicate age, grape variety, and climate.

2. Nose — condition (clean/faulty), intensity (light/medium(-)/medium/medium(+)/pronounced), aroma characteristics. Be precise: “medium(+) intensity, youthful, with primary aromas of blackcurrant, black cherry, and violet, with secondary aromas of vanilla, toast, and clove from oak, and hints of tertiary leather and cedar from bottle age.”

3. Palate — sweetness (dry through lusciously sweet), acidity (low through high), tannin (level AND quality: fine-grained, grippy, chalky, velvety), alcohol (low through high), body (light through full), flavour intensity and characteristics (should mirror and build on nose), finish (short/medium(-)/medium/medium(+)/long).

4. Conclusions — quality level with justification (“very good quality: the wine shows good concentration and complexity, with fine-grained tannins, balanced acidity, and a long finish; however, it lacks the exceptional complexity and length of an outstanding wine”), readiness for drinking (drink now, can age, too young), and identity if required.

Always justify your quality assessment with specific evidence from your tasting notes. “Outstanding” requires you to demonstrate exceptional complexity, concentration, and very long finish. “Good” requires balance and some complexity. A generic conclusion without evidence will score poorly.

D4 — Sparkling Wines Framework

Production Methods Comparison

Champagne in Detail

Grapes: Chardonnay (finesse, citrus, mineral — dominates Côte des Blancs), Pinot Noir (structure, red fruit, body — dominates Montagne de Reims), Pinot Meunier (fruit, roundness, approachability — dominates Vallée de la Marne).

Terroir: Chalk and limestone subsoil provides drainage, reflects heat, and contributes mineral character. Cool continental climate means high acidity in base wines. Northern latitude ensures slow, even ripening.

Key concepts:

• Non-vintage (NV): blend of multiple vintages; minimum 15 months on lees (most houses far exceed this); represents the consistent house style
• Vintage: single exceptional year; minimum 36 months on lees; released only in outstanding vintages
• Prestige cuvée: top bottling from the best parcels (e.g. Dom Pérignon, Cristal, Krug Grande Cuvée)
• Blanc de Blancs: 100% Chardonnay; elegant, citrus, mineral
• Blanc de Noirs: Pinot Noir and/or Meunier only; richer, red fruit
• Rosé: made by blending or saignée (brief skin contact); the only EU region where blending for rosé is the norm

Dosage levels: Brut Nature (0-3 g/L) → Extra Brut (0-6 g/L) → Brut (0-12 g/L) → Extra Dry (12-17 g/L) → Dry/Sec (17-32 g/L) → Demi-Sec (32-50 g/L) → Doux (50+ g/L). The dosage (liqueur d’expédition) is added after disgorgement to balance the wine’s high acidity.

Grower vs Négociant: RM (Récoltant-Manipulant) grows their own grapes; NM (Négociant-Manipulant) buys grapes. Grower Champagne emphasises terroir; négociant Champagne emphasises blending and house style consistency.

D5 — Fortified Wines Framework

Port Production and Styles

Production: grapes (primarily Touriga Nacional, Touriga Franca, Tinta Roriz, Tinta Barroca, Tinto Cão) are grown on the steep terraced slopes of the Douro Valley. Fermentation is stopped by adding aguardente (77% ABV grape spirit) when roughly half the sugar has been converted to alcohol, leaving the wine sweet (typically 80-100 g/L residual sugar) at around 19-22% ABV.

Style spectrum:

Sherry Production and Styles

Base wine: made from Palomino grape (for dry styles) or Pedro Ximénez / Muscat (for sweet styles), grown in the chalky albariza soil of the Jerez region.

Classification after fermentation: the winemaker classifies each barrel as either lighter (destined for biological ageing under flor) or fuller (destined for oxidative ageing). Lighter wines are fortified to 15% ABV to support flor growth. Fuller wines are fortified to 17% ABV, which kills flor and initiates oxidative ageing.

The solera system: fractional blending system using rows (criaderas) of barrels stacked by age. Wine is drawn from the oldest row (the solera) for bottling, and each row is replenished from the next youngest. This ensures consistency of style across years, as the average age of the blend remains stable.

Madeira Production

Madeira is unique among fortified wines for its intentional heating process, which gives the wines extraordinary longevity.

• Estufagem: heating wine to 45-50°C for minimum 3 months in heated tanks (estufa); used for cheaper Madeira
• Canteiro: natural warmth in warm attic rooms (canteiro) for years; used for premium Madeira from noble varieties
• Noble varieties (driest to sweetest): Sercial, Verdelho, Bual (Boal), Malmsey (Malvasia)
• Ageing designations: 3-year, 5-year, 10-year, 15-year, 20-year, Colheita (single vintage, 5+ years), Frasqueira/Vintage (single vintage, 20+ years)

Essay Writing Framework

Structure for Theory Papers

Every essay should follow this pattern:

1. Opening sentence — directly answer the question or define the scope (“The key factors that distinguish Left Bank from Right Bank Bordeaux are soil composition, dominant grape variety, and resulting wine style.”)
2. Body paragraphs — each paragraph makes one point, supported by evidence. Use the structure: claim → explanation → specific example. (“The gravel soils of the Haut-Médoc provide excellent drainage and heat retention, which favours the late-ripening Cabernet Sauvignon. For example, the deep gravel beds of Pauillac are the foundation of estates like Château Latour and Château Mouton Rothschild.”)
3. Compare and contrast — where relevant, show analytical thinking by drawing parallels and distinctions. (“While both Barolo and Brunello di Montalcino are tannic, age-worthy Italian reds, they differ fundamentally in grape variety, climate, and flavour profile.”)
4. Conclusion — tie back to the question; do not introduce new information.

Common Essay Mistakes to Avoid

• Too general — name specific appellations, producers, vintages, and data points. “France makes good wine” earns no marks. “The 2015 vintage in Bordeaux was exceptional due to a warm, dry summer that produced fully ripe Cabernet Sauvignon with physiologically mature tannins” demonstrates knowledge.
• Describing without explaining — state WHY, not just WHAT. “Chablis has high acidity” is descriptive. “Chablis has high acidity because of its cool continental climate, where grapes struggle to ripen fully, retaining high levels of tartaric and malic acid” is analytical.
• Ignoring the question — always re-read the question before writing your conclusion. If the question asks “compare,” you must discuss similarities AND differences. If it asks “evaluate,” you must make a judgement.
• Poor time management — plan 5 minutes per essay, write 20 minutes, review 5 minutes. Start with the question you are most confident about.

D6 — Research Assignment Tips

Choosing a Topic

Select a topic that is:

• Specific enough to cover thoroughly in 3,000 words (not “Italian wine” but “The impact of climate change on viticulture practices in Barolo over the past two decades”)
• Researchable with primary sources you can actually access (interviews, visits, surveys, data)
• Analytical rather than purely descriptive (avoid topics that result in a literature summary)
• Interesting to you — you will spend many hours on this; passion sustains effort

Structure

1. Introduction (300-400 words) — define scope, state thesis, outline approach
2. Methodology (200-300 words) — explain how you gathered evidence (interviews, surveys, site visits, data analysis)
3. Findings and analysis (1,500-1,800 words) — present evidence, analyse patterns, discuss implications
4. Conclusion (300-400 words) — summarise key findings, answer your thesis question, suggest areas for further research

Referencing

• Use Harvard or footnote referencing consistently throughout
• Reference all facts, statistics, and quotes
• Primary sources (interviews, emails, visit notes) are valued higher than secondary sources
• Word limit is strict: 3,000 words ±10% — the examiners will check

20 Key Concepts for the Diploma

1. Terroir is the interaction of climate, soil, topography, and human factors — not just soil
2. Phenolic ripeness is as important as sugar ripeness for determining harvest date
3. Indigenous yeasts add complexity but introduce fermentation risk
4. New French oak is fine-grained and subtle; new American oak is wider-grained and bolder
5. MLF softens acidity and is standard for reds but optional for whites
6. Whole-bunch fermentation adds structure, freshness, and spice complexity
7. The solera system produces consistent blends across vintages
8. Flor is a film of yeast that protects Fino Sherry from oxidation while adding flavour
9. Champagne assemblage is the art of blending grapes, vineyards, and vintages for consistency
10. The 1855 Bordeaux Classification has changed only once (Mouton Rothschild, 1973)
11. Burgundy’s quality hierarchy is vineyard-based; Bordeaux’s is estate-based
12. Continental climate = extreme seasons; maritime = moderate, ocean-influenced; Mediterranean = hot dry summer, mild wet winter
13. Phylloxera destroyed European vineyards in the late 1800s; grafting onto American rootstock was the solution
14. High altitude increases diurnal temperature range and UV exposure
15. Clay soils retain water; gravel soils drain well and retain heat
16. Chaptalization adds sugar to raise potential alcohol; banned in warm regions
17. Botrytis cinerea (noble rot) concentrates sugar in grapes for sweet wine production
18. The traditional method produces the finest bubbles through bottle fermentation and extended lees ageing
19. Port is fortified during fermentation (retaining sugar); dry Sherry is fortified after fermentation
20. Balance, length, intensity, and complexity are the four pillars of quality assessment in the SAT