CMS Certified Sommelier cheat sheet

Potential alcohol rule: about 16.8 g/L sugar in must ferments to roughly 1% ABV; chaptalization adds sugar before or during fermentation and is regulated by appellation.

Malolactic fermentation converts malic acid to lactic acid plus CO2, lowering acidity and adding diacetyl; it is inhibited by SO2, low temperature, and low pH.

Carbonic maceration ferments whole uncrushed berries under CO2 intracellularly, producing low-tannin, fruit-forward wines with banana and bubblegum aromas, as in Beaujolais.

Fortification timing decides style: spirit added before fermentation ends retains sugar for Port; spirit added after dry fermentation gives dry Sherry; mistelle is juice plus spirit.

Solera is fractional blending across rows of barrels: younger wine tops up older wine, maintaining a consistent house style in Sherry, Madeira, and Marsala.

Grape decision rules: Riesling equals high acid and petrol; Sauvignon Blanc equals high acid and grassy; Cabernet Sauvignon equals high tannin and blackcurrant; Pinot Noir equals low tannin and red cherry; Syrah equals pepper and black fruit; Nebbiolo equals tar, roses, and high tannin.

Appellation rules: Chablis is Chardonnay; Barolo is 100% Nebbiolo with minimum 38 months aging including 18 months in wood; Chianti Classico requires at least 80% Sangiovese.

Spirit rules: Cognac is double pot-distilled mostly from Ugni Blanc and aged in French oak; Armagnac uses column distillation; 100% agave tequila uses blue Weber; gin must include juniper.

Beverage service knowledge: sake seimaibuai is the remaining rice percentage, so lower numbers mean more polishing; beer bitterness is measured in IBU; EU wine labels declare sulfites above 10 mg/L.

Service sequence: greet and seat, water and menu, take order, wine service, food service, check back, clear, dessert, bill, farewell.

Wine service order: present the label to the host, open, pour a small taste to the host, then serve guests clockwise with women or elders first and host last; pour from the guest's right.

Sparkling wine opening: chill the bottle, hold at 45 degrees, hold the cork while loosening the cage, twist the bottle not the cork, point away, and ease out quietly.

Decanting old red: stand upright 24 to 48 hours, decant slowly over a light source, and stop when sediment reaches the shoulder; a basket may be needed.

Service temperatures: sparkling 6-8C, white 8-12C, light red 13-16C, full red 16-18C, dessert wine 6-8C.

Corked wine response: TCA causes musty wet-cardboard aromas; remove the bottle, replace without charge, inform the manager, and log it for supplier credit.

Pairing rules: acid cuts fat, tannin binds protein, sweetness balances spicy heat, salt enhances acidity, and food and wine intensity should match.

Glassware: fill about one-third; sparkling in flute or tulip, white in a smaller tulip, Bordeaux in a large tall glass, Burgundy in a wide balloon; avoid detergent residue.

Allergen and service rule: declare major allergens, label sulfites above 10 mg/L, confirm dietary needs, open bottles at the table, and never touch the rim or inside of glassware.

Deductive grid order: appearance (clarity, intensity, color, rim), nose (condition, intensity, development, aromas), palate (sweetness, acid, tannin, alcohol, body, flavor, finish), then conclusions.

Color cues: red purple rim suggests youth, garnet and brick indicate age, brown shows oxidation; white green-gold is youthful, gold suggests age or oak, amber indicates oxidation.

Climate cue: cool climate gives high acid, lower alcohol, and restrained fruit; warm climate gives riper fruit, higher alcohol, and lower acid.

Tannin cue: high tannin suggests Cabernet Sauvignon, Nebbiolo, Syrah, or Mourvedre; low tannin suggests Pinot Noir, Gamay, or Grenache.

Acid cue: high acid suggests cool climate or grapes such as Riesling, Sauvignon Blanc, and Pinot Noir; low acid suggests warm climate or Grenache.

Aroma stage: primary fruit and floral notes; secondary from fermentation and oak such as butter, toast, and vanilla; tertiary from aging such as leather, mushroom, honey, and nuts.

Old versus New World: Old World shows earth, mineral, restrained fruit, and higher acid; New World shows riper fruit, higher alcohol, and overt oak.

Variety signatures: Sauvignon Blanc is grassy and gooseberry; Riesling is lime and petrol; Chardonnay is apple and lemon with oak; Cabernet Sauvignon is blackcurrant and cedar; Pinot Noir is red cherry and earth; Syrah is pepper and blackberry.

Quality conclusion: judge balance of acid, tannin, alcohol, body, and length; then state complexity, typicity, grape, country, region, vintage range, and quality level.