Metatartaric acid
Metatartaric acid a polymeric lactone of variable composition obtained by heating tartaric acid.
It is used to prevent precipitation in wine and is listed as E number E353 as a food additive.
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Wikipedia
Metatartaric acid a polymeric lactone of variable composition obtained by heating tartaric acid.
It is used to prevent precipitation in wine and is listed as E number E353 as a food additive.