Hydrogenated Cottonseed Oil
» Hydrogenated Cottonseed Oil is the product obtained by refining and hydrogenating oil obtained from seeds of cultivated plants of various varieties of Gossypium hirsutum Linné or of other species of Gossypium (Fam. Malvaceae). 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 complies with the test for Fatty acid composition.
B: It complies with the test for Melting range.
Melting range, Class II 741: between 57 and 70.
Acid value 401 Dissolve about 10 g of Hydrogenated Cottonseed 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 titrate 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 Hydrogenated Cottonseed Oil exhibits the following composition profile of fatty acids, as determined in the section Fatty Acid Composition under Fats and Fixed Oils 401:
Alkaline impurities Dissolve by gentle heating 2.0 g of Hydrogenated Cottonseed 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 to a yellow endpoint: 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 Cottonseed 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, 2.0, 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. Extrapolate the line joining the points on the graph 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.