---
kind: "section"
citation: "27 C.F.R. § 21.124"
title: "27"
number: "21.124"
heading: "Quassin."
url: "https://uscodex.org/cfr/27/21.124"
---

# §21.124. Quassin.

- (a) **Quassin is the bitter principle of quassia wood (occurring as a mixture of two isomeric forms).** It shall be a good commercial grade of purified amorphous quassin, standardized as to bitterness.
- (b) **Bitterness.** An aqueous solution of quassin shall be distinctly bitter at a 1 to 250,000 dilution. To test: Dissolve 0.1 gram of quassin in 100 mL of 95 percent alcohol, then dilute 4 mL of the solution to 1,000 mL with distilled water, mix well and taste.
- (c) **Identification test.** Dissolve about 0.5 gram of quassin in 10 mL of 95 percent alcohol and filter. To 5 mL of the filtrate, add 5 mL of concentrated hydrochloric acid and 1 mg of phloroglucinol and mix well. A red color develops.
- (d) **Optical assay.** When 1 gram of quassin (in solution in a small amount of 95 percent alcohol) is dissolved in 10,000 mL of water, the absorbance of the solution in a 1 cm cell at a wavelength of 258 millimicrons shall not be less than 0.400.
- (e) **Solubility.** When 0.5 gram of quassin is added to 25 mL of 190 proof alcohol, it shall dissolve completely.

## Notes

### Amendments

[T.D. ATF-133, 48 FR 24673, June 2, 1983. Redesignated by T.D. ATF-442, 66 FR 12854, Mar. 1, 2001]

### Authority

Authority: 5 U.S.C. 552(a); 26 U.S.C. 5242, 7805.

### Source

Source: T.D. ATF-133, 48 FR 24673, June 2, 1983, unless otherwise noted.

### Amendments

[T.D. ATF-133, 48 FR 24673, June 2, 1983. Redesignated by T.D. ATF-442, 66 FR 12854, Mar. 1, 2001]