Hydrogenated Soybean Oil
» Hydrogenated Soybean Oil is the product obtained by refining, bleaching, hydrogenation, and deodorization of oil obtained from seeds of the soya plant Glycine max Merr. (Fabaceae). The product consists mainly of triglycerides of palmitic and stearic acids.
Packaging and storage— Preserve in tight, light-resistant containers. No storage requirements specified.
A: It meets the requirements of the test for Fatty acid composition.
B: It meets the requirements of the test for Melting range.
Melting range, Class II 741: between 66 and 72.
Acid value 401 Dissolve about 10 g of Hydrogenated Soybean Oil, accurately weighed, in 50 mL of a hot mixture of neutralized alcohol and toluene (1:1), add 0.5 mL of phenolphthalein TS, and immediately titrate, while still hot, with 0.1 N potassium hydroxide VS to produce a permanent, faint pink color: the acid value so obtained is not more than 0.5.
Peroxide value 401: not more than 5.0.
Unsaponifiable matter 401: not more than 1.0%, determined on 5.0 g.
Fatty acid composition 401 Hydrogenated Soybean Oil exhibits the following composition profile of fatty acids, as determined in the section Fatty Acid Composition.
No. of Double
Percentage (%)
<14 0 0.1
14 0 0.5
16 0 9–16
18 0 79–89
20 0 1.0
22 0 1.0
18 1 4.0
18 2 1.0
18 3 0.2
Alkaline impurities— Dissolve by gently heating 2.0 g of Hydrogenated Soybean Oil in a mixture of 1.5 mL of alcohol and 3.0 mL of toluene. Add 0.05 mL of bromophenol blue TS, and titrate with 0.01 N hydrochloric acid VS to a yellow endpoint: not more than 0.4 mL of 0.01 N hydrochloric acid is required.
Water, Method I 921: not more than 0.3%.
Limit of nickel—
Test solution— Weigh 5.0 g of Hydrogenated Soybean Oil into a previously tared platinum or silica crucible. Cautiously heat, and introduce into the substance a wick formed from twisted ashless filter paper. Ignite the wick. When the substance ignites, stop heating. After combustion, ignite in a muffle furnace at about 600. Continue the incineration until white ash is obtained. After cooling, transfer the residue, with the aid of two 2-mL portions of diluted hydrochloric acid, to a 25-mL volumetric flask, add 0.3 mL of nitric acid, and dilute with water to volume.
Nickel standard solution— Immediately before use, dilute 10 mL of nickel standard solution TS with water to 500 mL. This solution contains the equivalent of 0.2 µg of nickel per g.
Standard solutions— Into three identical 10-mL volumetric flasks, introduce respectively 1.0 mL, 2.0 mL, and 4.0 mL of Nickel standard solution. To each flask, add a 2.0-mL portion of the Test solution, and dilute with water to volume.
Procedure— Concomitantly determine the absorbances of the Standard solutions and the Test solution at least three times each, at the wavelength of maximum absorbance at 232.0 nm, with a suitable atomic absorption spectrophotometer (see Spectrophotometry and Light-Scattering 851) equipped with a graphite furnace and a nickel hollow-cathode lamp. Record the average of the steady readings for each of the Standard solutions and the Test solution. Plot the absorbances of the Standard solutions and the Test solution versus the added quantity of nickel, and draw the straight line best fitting the three plotted points. Extrapolate the line until it meets the concentration axis. The distance between this point and the intersection of the axes represents the concentration of nickel in the Test solution. Not more than 1 µg per g is found.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Hong Wang, Ph.D.
(EM205) Excipient Monographs 2
USP32–NF27 Page 1353
Pharmacopeial Forum: Volume No. 30(3) Page 995