Premature Oxidation Audit in a White Burgundy Program
A 120-seat restaurant has a 40-bottle white Burgundy section. The list includes 30 bottles of a single producer's 2014–2017 Meursault and Puligny-Montrachet, all sealed with natural cork. They are stored in a basement at 16–18°C, 55–65% humidity, under fluorescent lighting, and the basement has no temperature control. In eight months, five bottles have been returned by guests as oxidized: the wine is deep gold, smells of sherry and bruised apple, and has lost fruit. The sommelier has also noticed that the same wine by the glass tastes fresher from a newly opened bottle than from a bottle opened the previous day. The supplier says the wines were shipped at 14°C and stored in a temperature-controlled warehouse.
1. Diagnose the most likely causes of the oxidation and rank them.
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The most likely primary cause is premature oxidation, a bottle-variation problem linked to natural cork variability, low free sulfur at bottling, and winemaking choices; it is not simply age, because the wines are 2014–2017 and five of 30 bottles is a high random failure rate. Secondary causes are storage: 16–18°C is warm for long-term white Burgundy and lacks temperature control, and fluorescent light can accelerate oxidation. By-the-glass oxidation is a separate, expected cause after opening. I would rank premox first, storage second, and by-the-glass handling third, then verify with bottle records and cork condition.
2. What changes would you make to storage, list management, and by-the-glass service?
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Move the stock to a dark, stable 12–14°C cellar with 70% humidity and no fluorescent light. Reduce the by-the-glass offer to one bottle at a time, use argon or a vacuum system, and keep open bottles no more than 24 hours. Consider switching the list to a producer with Diam or screwcap closures if premox is confirmed. Train staff to check color and aroma before pouring, and keep a bottle log with lot numbers.
3. How do you handle a guest who returns a bottle and a supplier who denies responsibility?
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To the guest: apologize, replace the bottle immediately, and explain that the wine is oxidized, not a storage fault on the restaurant's part. To the supplier: document the returns with lot numbers, keep the bottles, request a credit or replacement, and send samples if requested. I would not accuse the supplier without evidence; I would present the pattern and ask for technical data on free sulfur and closure. Internally, I would flag the producer and suspend further purchases until the issue is resolved.