E353 – Metataric Acid
AntioxidantsDescription
White to yellowish powder, hygroscopic
Notes
Metatartaric acid is a white to yellowish powder that's made from regular tartaric acid through a heating process. Tartaric acid naturally occurs in grapes and is commonly obtained as a byproduct of winemaking, where it crystallizes out during fermentation and aging. When this tartaric acid is heated to high temperatures (around 170°C), it undergoes a chemical change that creates metatartaric acid. The powder is hygroscopic, meaning it readily absorbs moisture from the air. This additive works as a sequestrant specifically in wine production, where it prevents the formation of tartrate crystals – those harmless but unsightly crystals that can appear in wine bottles. Metatartaric acid binds to metal ions and other compounds that would otherwise cause these crystals to form, keeping wines clear and visually appealing. It's almost exclusively used in the wine industry rather than in general food products. Metatartaric acid is derived from natural sources (grapes) but is chemically modified, so it sits somewhere between natural and synthetic. It's suitable for vegetarians and vegans and generally doesn't pose concerns for most religious dietary laws. Wine treated with metatartaric acid is considered safe to drink, and the compound gradually breaks down over time, which is why it's particularly useful for wines meant to be consumed relatively young.