Today we would like to comment about how would affect the characteristics of two bottles of 750 ml of the same wine, if they blend in a decanter with capacity for 1.5 litres.
First of all, it is important to remember some essential concepts about decanting, as for example the different motives that advise the decanting of different wines. We decant young wines mainly to to soften harsh tannins and enhance primary fruit aromas. We also decant aged wines in order to remove possible sediments which might have formed during the period of aging in the bottle.
That said, for young wines it is fully accepted the action of blending two bottles in the same decanter, the important thing here would be tasting both wines previously for no defects. For aged-wines, variations during the period of aging in the bottle can occur, for that reason it is not recommended to mix two different bottles in the same decanter.
With reference to this last point, there are several factors that can cause variation in the characteristics of the wine. Among them it is worth mentioning the amount of oxygen that has passed through the Cork during the years of cellaring, which makes the wines evolve in a different way. For this reason, it is quite common to find two bottles of the same brand and year, displaying slightly different characteristics.