Silica Gel / Silicon Dioxide — Hidden Processing Agent — Is It Vegan?
Also known as: Amorphous silicon dioxide, E551, Diatomite silica, Kieselgel
Vegan
No animals or animal-derived substances are involved in producing this agent.
Not required on labels
E551 must be declared in powdered food ingredients where it is used as an anti-caking agent.
Source
Produced synthetically from sodium silicate (water glass) or naturally from diatomaceous earth. Both synthetic and natural forms are entirely inorganic.
Used In
Wine fining and clarification (removes proteins, tannins, and heat-unstable compounds), beer clarification, food anti-caking agent (E551 in powdered foods, spices, salt), moisture absorption packets.
How to Avoid
No need to avoid — silica gel is vegan.
Editorial Notes
Silica fining is one of the most common wine clarification methods — often used in combination with bentonite or other fining agents. The 'do not eat' packets found in shoe boxes and electronics are silica gel (silicon dioxide) — entirely vegan and non-toxic (though indigestible and unpleasant). Not to be confused with diatomaceous earth, which is mechanically similar but different in structure.