There is no generally accepted formal policy for dealing with wine bottle complaints in a restaurant, and the ultimate decision around the policy rests with each individual restaurant owner.
You can’t deal with faults with confidence if you don’t have a good command of the aromas of major wine faults. It is the Sommelier’s responsibility to make sure that there is always another staff member on duty in his/her absence who also have a sure ability to identify basic wine faults in bottled wines.
If a guest feels something is wrong, they should bring this to the waiter’s attention who should in turn let the sommelier or manager know. On a busy floor it’s wise to train waiters to be armed with a small tasting measure of the wine when they inform you. Each sommelier may handle this differently. Taste the wine and if you find it faulty, simply replace it with another bottle of the same wine. Make a note of this, and write the name of the fault and the date on the faulty bottle. Put the cork that the bottle came with (producers use this to reference cork suppliers) back in the bottle, and keep in a safe place in your store room where it can be collected by the supplier.
If you feel confident there is no problem you should let the customer know. At this stage perhaps suggest decanting the wine, and explain the elements in the flavor profile that you think may be bothering the guest. If they still insist that they’re not happy, try to persuade them to choose another producer (as it is more the style of the wine they’re not happy with).
If they prefer the same bottle, open a second and then sell the first bottle by the glass. They won’t have the option of returning that second bottle too, as you have advised them correctly, and they will have to pay for it.
We are in the business of caring for our customers, so therefore never force a guest to pay for something that is faulty. You do get customers that would drink ¾ of the bottle and then say it’s faulty, this I would not take back.
It is sensible to be less tolerant with younger wines, particularly with signs of oxidation (acetaldehydes and acetic acids / volatility), as there would be a high likelihood of the wine suffering from poor storage conditions (or even transport conditions) somewhere down the line, whereas with an older vintage it would be part of the wine’s expected maturing flavor profile. Darker colors in a young white wine and browning in reds can be a sign of premature ageing.
TCA (corked) however is consistent across wine types and the age and the physical condition of the cork is irrelevant.
The most common wine faults, with their basic aromatic indicators are:
– Cork taint (red & white): 2,4,6 tri-chloro anisole (TCA) – ‘Wet cardboard’ aroma.
– Volatile sulphur compounds (red & white): Stronger in white (Reductive characters, SLO’s) – H2S ‘rotten egg’ aroma.
– Acetaldehyde (red & white) – ‘Sherry’ aroma.
– Acetic acid (Red & White) – ‘Vinegar’ aroma.
– Ethyl acetate (red & white) – ‘Acetone’ aroma.
– Brettanomyces (Most common in red wines, but does sometimes occur in whites): 4-ethyl phenol (4-EP) ‘Band-aid’ aroma; 4-ethyl guaiacol (4-EG) ‘Leathery, sweaty’ aromas; isovaleric acid – Combination of aromas usually described as ‘barnyard’.
– Geosmin (red & white) – A musty/vegetal aroma – often described as ‘beetroot’.
– Higgo Jacobs –