Hydrogenated Palm Oil
R1COOCH2–CH(OOCR2)–CH2OOCR3
where R1, R2, and R3 are mainly C15 and C17.

Hydrogenated palm oil [68514-74-9].
» Hydrogenated Palm Oil is the product obtained by refining and hydrogenating the oil obtained from the pulp of the fruit of the oil palm Elaeis guineensis Jacq. (Fam. Aracaceae). The product consists mainly of triglycerides of palmitic and stearic acids.
Packaging and storage— Preserve in tight, light-resistant containers. No storage requirement specified.
Identification—
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 741: between 58 and 62.
Acid value, Method II 401: not more than 2.0.
Peroxide value 401: not more than 5.0.
Unsaponifiable matter 401: not more than 0.8%.
Fatty acid composition— Hydrogenated Palm Oil exhibits the following composition profile of fatty acids, as determined using the procedure in the section Fatty Acid Composition under Fats and Fixed Oils 401:
Carbon-Chain Length Number of Double Bonds Percentage (%)
12 0 2.5
14 0 0.5–5.9
16 0 32.0–47.0
18 0 49.0–57.0
20 0 1.0
22 0 1.0
16 1 2.5
18 1 2.5
18 2 0.5
18 3 0.5
Loss on drying 731 Dry it at 105 for 4 hours: it loses not more than 0.1% of its weight.
Residue on ignition 281: not more than 0.1%, 5 g of Hydrogenated Palm Oil being used.
Heavy metals, Method II 231: not more than 0.001%.
Alkaline impurities— Prepare a mixture of 2.0 g of Hydrogenated Palm Oil, 1.5 mL of alcohol, and 3.0 mL of toluene. Dissolve by gentle heating. Add 0.05 mL of bromophenol blue TS, and titrate with 0.01 N hydrochloric acid VS until the mixture turns yellow: not more than 0.4 mL of 0.01 N hydrochloric acid is required.
Limit of nickel—
Test solution— Weigh 5.0 g of Hydrogenated Palm Oil into a previously tared platinum or silica crucible. Cautiously heat the substance, and introduce into it 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 a white ash is obtained. After cooling, with the aid of two 2-mL portions of diluted hydrochloric acid, transfer the residue 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 mL.
Standard solutions— Into four separate identical 10-mL volumetric flasks, introduce respectively 0 mL, 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 to obtain four Standard solutions containing added quantities of 0 µg, 0.2 µg, 0.4 µg, and 0.8 µg of nickel, respectively.
Procedure— Concomitantly determine the absorbances of the Standard solutions 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. Plot the absorbances of the Standard solutions versus the added quantity, in µg, of nickel. Extrapolate the line joining the points on the graph until it meets the quantity axis. The distance between this point and the intersection of the axes represents the quantity of nickel, A, in µg, in the 2-mL portion of Test solution. Calculate the content of nickel in the portion of Hydrogenated Palm Oil taken by the formula:
25(A / 2) / W
in which 25 is the volume, in mL, of the Test solution; A is as determined above; 2 is the volume, in mL, of the Test solution added to the Standard solutions; and W is the weight, in g, of Hydrogenated Palm Oil taken to prepare the Test solution: not more than 1 µg per g is found.
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(EXC2010) Monographs - Excipients
USP35–NF30 Page 1883
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