Propyl Gallate
The most effective naturally derived antioxidant for the food industry. Propyl Gallate is made from natural Gallic Acid, which is obtained by the hydrolysis of tannins from Tara pods. It exhibits excellent antioxidant activity in food and vegetable oils, especially in combination with Ascorbyl Palmitate.
Propyl Gallate
Gallic Acid, Propyl Ester
C10H12O5
Formula wt 180.20
INS: 310
CAS: [121-79-9]
Description
A fine, white to nearly white, odorless powder having a slightly bitter taste. It is slightly soluble in water and freely soluble in alcohol and in either.
Functional Use in Foods: Antioxidant.
Requirements
Identification: Place about 5 g of the sample and several boiling chips in 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 reaction 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 110o for 2 h. The gallic acid so obtained melts at about 240o with decomposition.
Assay: Not less than 98.0% and not more than 102.0% of C10H12O5 after drying.
Heavy Metals (as Pb): Not more than 10 mg/kg.
Loss on Drying: Not more than 0.5%.
Melting Range: Between 146o and 150o.
Residue on Ignition: Not more than 0.1%.
Tests
Assay: Transfer about 200 mg, previously dried at 110o for 4 h and accurately weighed, to a 400-mL beaker, dissolve it in 150 mL of water, and heat to boiling. With constant and vigorous stirring, add 50 mL of bismuth nitrate TS, continue stirring and heating until precipitation is complete, and cool. Filter the yellow precipitate on a tared sintered-glass crucible, wash it with cold dilute nitric acid (1 in 300), and dry at 110o to constant weight. The weight of the precipitate so obtained, multiplied by 0.4866, represents its equivalent of C10H12O5.
Heavy Metals: Prepare and test a 2-g sample as directed in Method II under the Heavy Metals Test, (Appendix IIIB) using 20 µg of lead ion (Pb) in the control (Solution A).
Loss on Drying: Appendix IIC - Dry at 110o for 4 h.
Melting Range: Determine as directed for Melting Range or Temperature, Appendix IIB, after drying at 110o for 4 h.
Residue on Ignition: Appendix IIC - Ignite 2 g as directed in the general method.
Packaging and storage Store in well-closed containers.
Reference: FCC IV
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