Packaging and storage
Preserve in tight containers.
Solubility and reaction
Dissolve 1g in 2mLof water;the resulting solution flows readily and is acid to litmus.
Botanic characteristics
Acacia
Spheroidal tears up to 32mm in diameter or in angular fragments of white to yellowish white color.Is translucent or somewhat opaque from the presence of numerous minute fissures;very brittle,the fractured surface glassy and occasionally iridescent.Is almost odorless and produces a mucilaginous sensation on the tongue.
Flake Acacia
White to yellowish white,thin flakes,appearing under the microscope as colorless,striated fragments.
Powdered Acacia
White to yellowish white,angular microscopic fragments with only traces of starch or vegetable tissues present.
Granular Acacia
White to pale yellowish white,fine granules.Under the microscope it appears as colorless,glassy,irregularly angular fragments up to 100µm in thickness,some of which exhibit parallel linear streaks.
Spray-dried Acacia
White to off-white compacted microscopic fragments or whole spheres.
Identification
To 10mLof a cold solution (1in 50)add 0.2mLof diluted lead subacetate TS:a flocculent,or curdy,white precipitate is formed immediately.
Water,Method IIIá921ñ
Dry it at 105

for 5hours:it loses not more than 15.0%of its weight.For unground Acacia,crush it in a mortar until it passes through a No.40sieve,and mix the ground material before weighing the test specimen.
Insoluble residue
Dissolve 5.0g of powdered or finely ground Acacia in about 100mLof water in a 250-mLconical flask,add 10mLof 3Nhydrochloric acid,and boil gently for 15minutes.Filter by suction,while hot,through a tared filtering crucible,wash thoroughly with hot water,dry at 105

for 1hour,and weigh.The weight of the residue thus obtained does not exceed 50mg.
Starch or dextrin
Boil a solution (1in 50),cool,and add iodine TS:no bluish or reddish color is produced.
Tannin-bearing gums
To 10mLof a solution (1in 50)add 0.1mLof ferric chloride TS:no blackish coloration or blackish precipitate is produced.