Packaging and storage— Preserve in tight containers, and avoid exposure to excessive heat.

Rosin, rosin oil, and copaiba— Place 1 g, powdered or crushed if necessary, in a small mortar, and add 10 mL of petroleum benzin. Triturate well for 1 to 2 minutes, filter into a test tube, and to the filtrate so obtained add 10 mL of freshly prepared cupric acetate solution (1 in 200). Shake, and allow the phases to separate: the petroleum benzin layer does not show a green color.

Acid value 401— Dissolve about 1 g, accurately weighed, in 50 mL of neutralized alcohol, add phenolphthalein TS, and titrate with 0.5 N alcoholic potassium hydroxide VS: the acid value is between 112 and 168.

Saponification value 401— Add sufficient 0.5 N alcoholic potassium hydroxide VS to the neutralized liquid obtained in the test for Acid value to make the total volume of the alkali solution added 20.0 mL, heat the liquid on a steam bath for 30 minutes under a reflux condenser, and cool. Add about 200 mL of water, or more if necessary, and titrate the excess potassium hydroxide with 0.5 N hydrochloric acid VS. Perform a blank determination (see Residual Titrations under Titrimetry 541). The total volume of 0.5 N alcoholic potassium hydroxide consumed, including that required to neutralize the free acid in the determination of Acid value, is equivalent to a saponification value of between 154 and 220.

Topic/Question	Contact	Expert Committee
Monograph	Hong Wang, Ph.D. Scientist 1-301-816-8351	(EM205) Excipient Monographs 2

USP32–NF27 Page 3773

TOLU BALSAM

Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.