Bottling, filtration and storage

Shortly before bottling the winemaker decides on filtration and fining. Filtration removes particles and microorganisms such as yeast and bacteria to stabilise the wine. There is a spectrum from coarse filtration (removing large particles) to sterile filtration (removing all yeast and bacteria). Critics argue that intensive filtration can remove texture and depth. Fining involves adding an agent — bentonite, egg white, fish gelatin — that binds to particles and settles out. In the bottle a new phase of maturation begins. Reducing conditions (low oxygen) under cork favour fruit-preserving reductive reactions. Wines with high tannin, acidity and extract can age for decades. Storage at cellar temperature (12–15 °C), dark and vibration-free provides optimal maturation.