Soybean Oil
(soi' been oyl).
» Soybean Oil is the refined fixed oil obtained from the seeds of the soya plant Glycine max Merr. (Fabaceae). It may contain suitable antioxidants.
Packaging and storage— Preserve in tight, light-resistant containers, and avoid exposure to excessive heat.
Labeling— Label it to indicate the name and quantity of any added antioxidant. Where Soybean Oil is intended for use in the manufacture of injectable dosage forms, it is so labeled.
Identification— It meets the requirements of the test for Fatty acid composition.
Heavy metals, Method II 231: not more than 0.001%.
Acid value 401: not more than 0.3.
Fatty acid composition— Soybean Oil exhibits the following composition profile of fatty acids, as determined in the section Fatty Acid Composition under Fats and Fixed Oils 401:
Carbon-Chain Length Number of Double Bonds Percentage (%)
<14 0 0.1
14 0 0.2
16 0 9.0–13.0
16 1 0.3
18 0 2.5–5.0
18 1 17.0–30.0
18 2 48.0–58.0
18 3 5.0–11.0
20 0 1.0
20 1 1.0
22 0 1.0
22 1 0.3
24 0 0.5
Unsaponifiable matter 401: not more than 1.5%.
Peroxide value 401
Mixed solvent— Mix 60 mL of glacial acetic acid with 40 mL of chloroform.
Potassium iodide solution— Prepare a saturated solution of potassium iodide in freshly boiled and cooled water, and store it protected from light. Discard it if it gives a color on addition of Mixed solvent and starch TS.
Procedure— Transfer about 10 g of Oil, accurately weighed, to a conical flask, add 30 mL of Mixed solvent, swirl to dissolve, add 0.5 mL of Potassium iodide solution, swirl the flask for 1 minute, accurately timed, add 30 mL of water, and titrate with 0.01 N sodium thiosulfate VS, with vigorous agitation, to a light yellow color. Add 0.5 mL of starch TS, and continue the titration until the blue color has disappeared. Perform a blank test, and make any necessary correction. Calculate the peroxide content, in mEq per kg, taken by the formula:
in which V is the volume, in mL, of sodium thiosulfate required and N is its normality; and W is the weight, in g, of Oil taken. The limit is 10.0.
Water, Method Ic 921: not more than 0.1%.
Alkaline impurities— Mix 10 mL of acetone and 0.3 mL of water, and add 0.05 mL of bromophenol blue TS. If necessary, neutralize the solution to a green color with 0.01 N hydrochloric acid or 0.01 N sodium hydroxide. Add 10 mL of Soybean Oil, shake, and allow to stand. Titrate with 0.01 N hydrochloric acid VS to change the color of the upper layer to yellow: not more than 0.1 mL of 0.01 N hydrochloric acid is required.
Sterol composition— Proceed as directed in the section Sterol Composition under Fats and Fixed Oils 401: the sterol fraction of the Oil contains not more than 0.3% of brassicasterol.
Other requirements— For Soybean Oil intended for use in injectable dosage forms, which is specified in the Labeling, the requirements for Acid Value, Peroxide Value, Unsaponifiable Matter, and Water in the subsection Other Vehicles of the section Ingredients under Injections 1 must be met.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Robert H. Lafaver, M.S.
Scientific Liaison
(EXC2010) Monographs - Excipients
USP35–NF30 Page 4678
Pharmacopeial Forum: Volume No. 34(4) Page 989