Have the wines tasted at the right temperature. Dry white wines must be tasted at 8-12ºС. Dry white aromatic wines - at 12ºС. The more aromatic the white wine is, the higher its tasting temperature must be. Sparkling wines should be tasted at 5-8ºС, with 6ºС being considered as optimal. Red wines are usually tasted at room temperature, yet the more precise definition is 16-18ºС.
Open the bottle 2 hours in advance - the wine should take some air. This does not apply to sparkling wines.
The tasting should usually start with the youngest wine and proceeds towards the one with the oldest year of vintage. By terms of sweetness, the tasting starts from dry non-aromatic wines and moves to sweet aromatic. When these two criteria contradict, the factor of vintage year prevails.
Always take a sniff at the cork. It sometimes happens to be defective and the wine therefore deteriorated or compromised - the smell of the cork will reveal this. Simply have the bottle replaced and you will have the wine justfully evaluated.