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Colloidal Oatmeal
» Colloidal Oatmeal is the powder resulting from the grinding and further processing of whole oat grain meeting U.S. Standards for Number 1 or Number 2 oats (7 CFR 810.1001).
Packaging and storage— Preserve in well-closed containers.
A: Prepare a smooth mixture of 10 g of Colloidal Oatmeal and 100 mL of warm water. After stirring for 10 minutes, the resulting slurry has a characteristic slippery feel and shows the development of slimy, viscous strands.
B: A water slurry is colored reddish violet to deep blue by iodine TS.
Viscosity 911
Sample preparation— Transfer 25 g of Colloidal Oatmeal in small portions, with stirring at 1000 rpm over a 1 minute period, to 500 mL of water contained in a beaker, maintained at 45 and equipped with a variable speed mixer. Stir for 5 minutes after the addition of the last portion of oatmeal. Allow the suspension to stand for 90 minutes, and equilibrate to ambient temperature. Stir the suspension at 800 rpm for 1 minute.
Apparatus— Equip a suitable rotational viscosimeter with a spindle having a cylinder 1.88 cm in diameter and 6.25 cm high attached to a shaft 0.32 cm in diameter, the distance from the top of the cylinder to the lower tip of the shaft being 0.75 cm, and the immersion depth being 8.15 cm (No. 1 spindle).
Procedure— Determine and record the viscosity of the suspension, with the spindle rotating at 60 rpm. Convert to centipoise by multiplying the reading by the constant for the viscosimeter spindle and speed employed. The average of three viscosities obtained is greater than 1 and less than 100 centipoises.
Microbial limits 61 The total aerobic microbial count does not exceed 10,000 cfu per g. The total combined molds and yeasts count does not exceed 150 cfu per g.
Loss on drying 731 Dry it at 120 for 4 hours; it loses not more than 10% of its weight.
Particle size 786: not more than 3% of the total particles exceed 150 µm in size and not more than 20% of the total particles exceed 75 µm in size.
Total ash 561: not more than 2.5%, calculated on the dried basis.
Fat content— Dry about 4 g, accurately weighed, in vacuum at 100 for about 5 hours. Extract the fat from it with the anhydrous ethyl ether, using a continuous extraction apparatus, the extraction period being about 4 hours at a condensation rate of 5 to 6 drops per second. Evaporate the ether from the extract, transfer it to a tared beaker, and dry at 100 to constant weight. Perform a blank determination. The percentage of fat found, corrected for the blank, is not less than 0.2%.
Nitrogen content, Method I 461: not less than 2.0%.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Auxiliary Information— Staff Liaison : Feiwen Mao, M.S., Senior Scientific Associate
Expert Committee : (MDOOD05) Monograph Development-Ophthalmics Oncologics and Dermatologicals
USP29–NF24 Page 591
Phone Number : 1-301-816-8320