Gum Arabic is, technically, a polysaccharide and a resin like substance from an Arabic acacia tree. Its use is permitted in winemaker. Nothing particularly strange about that. It is a regular food additive with the code E414.
So what is it good for? It has two primary effects in wine: The first is to stabilise the colour, i.e. to avoid unwanted colour changes of the wine. Generally, it is to keep a darker colour of the wine. the other effect is to give the wine somewhat softer tannins and a rounder mouth-feel. It is normally only used in the making of simpler red wines made to be drunk young.
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