We offer Gallic Acid, , Methyl Gallate, Ethyl Gallate, Butyl Gallate, Propyl Gallate, Octyl Gallate and other antioxidants.

General Specifications of Propyl Gallate:

Description: White to almost white crystalline   powder, odorless or almost odorless.
Solubility: Very slightly soluble in water, freely soluble in ethanol (90 per cent). It dissolve in dilute solutions of alkali hydroxides.
Melting Point: 148C to151C
Appearance of Solution: The solution is clear and not  more intensely colored than reference solution.
Gallic Acid: Maximum 0.50%
Total Chloride: Maximum 200 ppm
Chloride: Maximum 100 ppm
Sulphate: Maximum 12%
Zinc: Maximum 25ppm
Heavy Metals: Maximum 10 ppm
Sulphated Ash: Maximum 0.1%
Loss on Drying at 150C: Maximum 0.5%
Assay: Minimum 99.00%.

Propyl Gallate BP Grade

Ph Eur --- C10H12O5 --- 212.2 --- 121-79-9
Action and use: Antioxidant.

DEFINITION
Propyl gallate contains not less than 97.0 per cent and not more than the equivalent of 103.0 per cent of propyl 3,4,5-trihydroxybenzoate, calculated with reference to the dried substance.

CHARACTERS
A white or almost white, crystalline powder, very slightly soluble in water, freely soluble in ethanol (96 per cent). It dissolves in dilute solutions of alkali hydroxides.

IDENTIFICATION
First identificationiB.
Second identificationiA, C, D.
A. Melting point: 148C to 151C.
B. Examine by infrared absorption spectrophotometry.
C. Examine the chromatograms obtained in the test for gallic acid.
D. Dissolve about 10 mg in 10 ml of water by heating to about 70C. Cool and add 1 ml of bismuth subnitrate solution. A bright yellow precipitate is formed.

TESTS
Appearance of solution: Dissolve 1.0 g in ethanol (96 per cent) and dilute to 20 ml with the same solvent. The solution is clear and not more intensely coloured than reference solution.
Gallic acid: Examine by thin-layer chromatography.
Total chlorine: Mix 0.5 g with 2 g of calcium carbonate. Dry and ignite at 700 ± 50C. Take up the residue with 20 ml of dilute nitric acid and dilute to 30 ml with water. 15 ml of the solution, without further addition of dilute nitric acid, complies with the limit test for chlorides (200 ppm).
Chlorides: To 1.65 g add 50 ml of water. Shake for 5 min. Filter. 15 ml of the filtrate complies with the limit test for chlorides (100 ppm).
Zinc: Not more than 25.0 ppm of Zn, determined by atomic absorption spectrometry
Heavy metals: 2.0 g complies with limit test C for heavy metals (10 ppm). Prepare the reference solution using 2 ml of lead standard solution (10 ppm Pb).
Loss on drying: Not more than 0.5 per cent, determined on 1.000 g by drying in an oven at 105C.
Sulphated ash: Not more than 0.1 per cent, determined on 1.0 g.

ASSAY
Dissolve 0.100 g in methanol and dilute to 250.0 ml with the same solvent. Dilute 5.0 ml of the solution to 200.0 ml with methanol. Measure the absorbance at the absorption maximum at 275 nm.
Calculate the content of C10H12O5 taking the specific absorbance to be 503.

STORAGE
Protected from light.

IMPURITIES
Specified impurities 3,4,5-trihydroxybenzoic acid (gallic acid).

Propyl Gallate USP Grade

C10H12O5 --- 212.20 --- [121-79-9].
Benzoic acid, 3,4,5-trihydroxy-, propyl ester.
Propyl Gallate contains not less than 98.0 percent and not more than 102.0 percent of C10H12O5, calculated on the dried basis.

Packaging and storage: Preserve in tight containers, protected from light, and avoid contact with metals.

Identification:
A: Infrared Absorption 197M .
B: Ultraviolet Absorption 197U
Solution: 10 3g per mL.
Medium: methanol.
Melting range: between 146 and 150 .
Loss on drying: Dry it at 105 for 4 hours: it loses not more than 0.5% of its weight.
Residue on ignition: not more than 0.1%.
Heavy metals: 0.001%.
Assay: Transfer about 100 mg of Propyl Gallate, accurately weighed, to a 250-mL volumetric flask, dissolve in about 100 mL of methanol, dilute with methanol to volume, and mix. Transfer 5.0 mL of this solution to a 200-mL volumetric flask, dilute with methanol to volume, and mix. Concomitantly determine the absorbances of this solution and a Standard solution of USP Propyl Gallate RS in methanol having a known concentration of about 10 micro gm per mL, in 1-cm cells at the wavelength of maximum absorbance at about 273 nm, with a suitable spectrophotometer, using methanol as the blank. Calculate the quantity, in mg, of C10H12O5 in the portion of Propyl Gallate taken by the formula:
10C(AU / AS)
in which C is the concentration, in microgm per mL, of USP Propyl Gallate in the Standard solution, and AU and AS are the absorbances of the solution of Propyl Gallate and the Standard solution, respectively.

Propyl Gallate FCC Food Grade

Gallic Acid, Propyl Ester
C10H12O5 Formula wt 212.20
INS: 310 CAS: [121-79-9]

DESCRIPTION
Propyl Gallate occurs as a fine, white to nearly white powder. It is slightly soluble in water and freely soluble in alcohol and in ether.
Function: Antioxidant.

REQUIREMENTS
Identification: Place about 5 g of sample and several boiling chips into a 500-mL round-bottom flask, connect a water-cooled condenser to the flask, and introduce a steady stream of nitrogen into the flask, maintaining the flow of nitrogen at all times during the remainder of the procedure. Pour 100 mL of 1 N sodium hydroxide through the top of the condenser, heat the solution to boiling, boil for 30 min, and cool. Place the round-bottom flask in an ice bath, and slowly, with occasional swirling, add dilute sulfuric acid (10%) until a pH of 2 to 3 is obtained (using pH paper). Filter the precipitate through a sintered-glass crucible, wash with a minimum amount of water, and dry at 110C for 2 h. The gallic acid so obtained melts at about 240C with decomposition.
Assay: Not less than 98.0% and not more than 102.0% of C10H12O5 after drying.
Lead: Not more than 1 mg/kg.
Loss on Drying: Not more than 0.5%.
Melting Range: Between 146C and 150C.
Residue on Ignition: Not more than 0.1%.