Key Facts

Other Names:

Penta-(m-digalloyl)-glucose; tannin; gallotannin

Formula:

C₇₆H₅₂O₄₆

Elements:

Carbon, hydrogen, oxygen

Compound Type:

Organic

State:

Solid

Molecular Weight:

1701.20 g/mol

Melting Point:

Begins to decompose at 210°C (410°F)

Boiling Point:

Not applicable

Solubility:

Soluble in water, ethyl alcohol, and acetone

Overview

Tannic acid (TAN-ik AS-id) is a pale yellow amorphous powder, shiny scales, or spongy material that gradually darkens when exposed to air. It is odorless but has a strong, bitter taste. It is a derivative of the simple sugar glucose (C₆H₁₂O₆) in which five hydroxyl groups (-OH) have been replaced by large complex side chains known as digalloyl groups. Tannic acid occurs naturally in the bark of hemlock, chestnut, mangrove, and oak trees; in sumac plants; and in plant galls, the hard swellings that develop on trees infested with insect parasites. The name tannic acid comes from...