| (Tentative) | |
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Prepared at the 55th JECFA (2000) and published in FNP 52 Add 8 (2000), superseding tentative specifications prepared at the 20th JECFA (1976) and published in FNS 1B (1977) and in FNP 52 (1992). An ADI of 0-25 mg/kg bw was established at the 17th JECFA (1973). Information on the levels of epoxides and suitable methods for the determination of epoxides is requested. Comments on other aspects of the monograph are invited. If no information is forthcoming before 1 May 2001, this monograph will be withdrawn. |
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SYNONYMS |
INS No. 387 |
DEFINITION |
A mixture of glycerides of partially oxidized stearic and other fatty acids; obtained by heating hydrogenated vegetable oil under controlled conditions |
DESCRIPTION |
Tan to light brown, fatty or wax-like substance |
FUNCTIONAL USES |
Crystallization inhibitor, sequestrant, antifoaming agent |
CHARACTERISTICS | |
IDENTIFICATION | |
Solubility (FNP 5) |
Soluble in ether and in hexane |
PURITY | |
Refractive index (FNP 5) |
Between 1.465 and 1.467 at 48o by the following procedure. Melt the sample, filter through filter paper and determine the refractive index at 48o. |
Acid value (FNP 5) |
Not more than 15 Use about 8 g of the sample weighed to the nearest mg. |
Hydroxyl value (FNP 5) |
Between 30 and 45 Use about 5 g of the sample weighed to the nearest mg |
Iodine value (FNP 5) |
Not more than 15 Use about 1 g of the sample weighed to the nearest mg |
Saponification value (FNP 5) |
Between 225 and 240 Use about 3 g of the sample weighed to the nearest mg |
Unsaponifiable matter |
Not more than 0.8% See description under TESTS |
Lead |
Not more than 2 mg/kg Determine using an atomic absorption technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on the principles of the method described in FNP 5, “Instrumental Methods”. |
TESTS | |
PURITY TESTS | |
Unsaponifiable matter |
Accurately weigh about 5 g of the sample into a 250 ml round-bottomed flask. Add a solution of 2 g of potassium hydroxide in 40 ml of ethanol and boil gently under a reflux condenser for 1 h or until saponification is complete. Transfer the contents of the flask to a glass-stoppered extraction cylinder (approximately 30 cm in height, 3.5 cm in diameter, and graduated at 40, 80 and 130 ml). Wash the flask with sufficient ethanol to make a volume of 40 ml in the cylinder, and complete the transfer with warm and then cold water until the total volume is 80 ml. Finally, wash the flask with a few ml of petroleum ether, add the washings to the cylinder, cool the contents of the cylinder to room temperature, and add 50 ml of petroleum ether.
Insert the stopper, shake the cylinder vigorously for at least 1 min, and allow both layers to become clear. Siphon the upper layer as completely as possible without removing any of the lower layer, collecting the ether fraction in a 500-ml separator. Repeat the extraction and siphoning at least six times with 50-ml portions of petroleum ether, shaking vigorously each time. Wash the combined extracts, with vigorous shaking, with 25-ml portions of 10% ethanol until the wash water is neutral to phenolphthalein and discard the washings. Transfer the ether extract to a tared beaker, and rinse the separator with 10 ml of ether, adding the rinsings to the beaker. Evaporate the ether on a steam bath just to dryness, and dry the residue to constant weight, preferably at 75-80o under vacuum of not more than 200 mm of Hg, or at 100o for 30 min. Cool in a desiccator, and weigh to obtain the uncorrected weight of unsaponifiable matter.
Determine the quantity of fatty acids in the residue as follows: Dissolve the residue in 50 ml of warm ethanol (containing phenolphthalein TS and previously neutralized with sodium hydroxide to a faint pink colour), and titrate with 0.02 N sodium hydroxide to the same colour. Each ml of 0.02 N sodium hydroxide is equivalent to 5.659 mg of fatty acids, calculated as oleic acid.
Subtract the calculated weight of fatty acids from the weight of the residue obtained to obtain the corrected weight of unsaponifiable matter in the sample. |