Reduction (see there) is a complex chemical process. In winemaking, reductive ageing is understood to mean the complete exclusion of the oxygen required for the metabolism of microorganisms and thus the prevention of undesirable oxidation. This requirement is met by minimising transport routes and processing times for grapes, must and wine with cool ambient conditions during pressing, must treatment, fermentation, ageing in hermetically sealed containers (steel tanks) and bottling. This is also supported by measures such as sulphurisation, fining and filtration.
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Sigi Hiss
freier Autor und Weinberater (Fine, Vinum u.a.), Bad Krozingen