Cocoa Butter
»Cocoa Butter is the fat obtained from the seed of Theobroma cacaoLinné(Fam.Sterculiaceae).
Packaging and storage—
Preserve in well-closed containers.
Melting range—
Melt the material to be tested at a temperature between 50
and 60.Place about 50g of the melted material in a beaker,and cool in a water bath at 25.Stir continuously until it assumes a pasty consistency,taking care to avoid the inclusion of air bubbles.Place the beaker in a water bath maintained at a temperature between 32and 33.Continue stirring until the specimen reaches the temperature of the water bath and changes to a liquid cream (about 30minutes).Pour the contents into another beaker,and allow it to solidify at room temperature for at least 2hours.Press one side of a U-shaped capillary tube,1.5mm in diameter and about 80mm in length with a distance of about 10mm between both capillaries,into the solidified specimen.Using a very fine metal rod,push the column down to 10mm before the bend of the U-tube.Then attach the other arm of the U-tube to a precision thermometer (having 0.1graduations)by suitable means,with the U-tube bend at the level of the thermometer bulb.Insert the thermometer into a water bath so that the upper edge of the material is at least 20mm below the surface,and heat as directed for Class Iunder Melting Range or Temperature á741ñexcept,within 5of the expected melting temperature,to regulate the rate of the temperature rise so that it does not exceed 0.2per minute.The slip point (temperature at which the column visibly flows towards the bend in the tube)is between 30and 34.The clear melting point (clarity via magnifying glass)is between 31and 35.
and 60.Place about 50g of the melted material in a beaker,and cool in a water bath at 25.Stir continuously until it assumes a pasty consistency,taking care to avoid the inclusion of air bubbles.Place the beaker in a water bath maintained at a temperature between 32and 33.Continue stirring until the specimen reaches the temperature of the water bath and changes to a liquid cream (about 30minutes).Pour the contents into another beaker,and allow it to solidify at room temperature for at least 2hours.Press one side of a U-shaped capillary tube,1.5mm in diameter and about 80mm in length with a distance of about 10mm between both capillaries,into the solidified specimen.Using a very fine metal rod,push the column down to 10mm before the bend of the U-tube.Then attach the other arm of the U-tube to a precision thermometer (having 0.1graduations)by suitable means,with the U-tube bend at the level of the thermometer bulb.Insert the thermometer into a water bath so that the upper edge of the material is at least 20mm below the surface,and heat as directed for Class Iunder Melting Range or Temperature á741ñexcept,within 5of the expected melting temperature,to regulate the rate of the temperature rise so that it does not exceed 0.2per minute.The slip point (temperature at which the column visibly flows towards the bend in the tube)is between 30and 34.The clear melting point (clarity via magnifying glass)is between 31and 35.
Free fatty acids á401ñ—
The free fatty acids in 10.0g of it require for neutralization not more than 5.0mLof 0.10Nsodium hydroxide (1.4%as oleic acid).
Refractive index á831ñ:
between 1.454and 1.459at 40.
.
Change to read:
Fatty acid composition—
Test solution—
Place about 100to 150mg of Cocoa Butter in a 50-mLround-bottom flask,and add 4mLof 0.5Nsodium hydroxide solution,prepared in methanol.Add a few boiling chips to the flask,connect the round-bottom flask to a condenser,and boil the mixture under total reflux until the fat globules go into solution.Add 5.0mLof a 2.0Mborontrifluoride in methanol solution to the boiling mixture via the condenser,and continue boiling for 2minutes.Add 2to 5mLof chromatographic n-heptane to the boiling mixture via the condenser,and boil for another minute.Remove the flask from the source of heat,and remove the reflux condenser.Add saturated sodium chloride solution,and swirl the flask gently.Add more of the saturated sodium chloride solution to bring the liquid level into the neck of the round-bottom flask.Transfer about 1mLof the organic layer into a glass-stoppered test tube,add some anhydrous sodium sulfate to remove the last traces of water,and filter.Use the filtrate.
System suitability solution—
Dissolve suitable quantities of methyl stearate and methyl oleate in n-heptane to obtain a solution having a known concentration of about 1mg per mLfor each component.
Chromatographic system(see Chromatography á621ñ)—
The gas chromatograph is equipped with a flame-ionization detector maintained at a temperature of about 250,a 0.25-mm ×15-m fused-silica capillary column coated with 0.25-µm stationary phase G19,and a split injection system with a split ratio of about 60:1,maintained at a temperature of about 250.The carrier gas is helium flowing at a linear velocity of about 48cm per second.The column temperature is programmed to increase linearly from 180to 240at a rate of 10per minute,and is maintained at 240for 5minutes.[NOTE—The components of interest elute during the temperature program.The final hold at a temperature of 240serves only to facilitate elution of higher boiling components.]Inject about 0.1µLof the System suitability solutioninto the chromatograph,record the chromatogram,and measure the responses for the major peaks:the relative retention times are about 0.97for stearate and 1.0for oleate;the resolution,R,between the stearate and oleate peaks is not less than 1.5;and the relative standard deviation for replicate injections is not more than 
5.0%.NF23
,a 0.25-mm ×15-m fused-silica capillary column coated with 0.25-µm stationary phase G19,and a split injection system with a split ratio of about 60:1,maintained at a temperature of about 250.The carrier gas is helium flowing at a linear velocity of about 48cm per second.The column temperature is programmed to increase linearly from 180to 240at a rate of 10per minute,and is maintained at 240for 5minutes.[NOTE—The components of interest elute during the temperature program.The final hold at a temperature of 240serves only to facilitate elution of higher boiling components.]Inject about 0.1µLof the System suitability solutioninto the chromatograph,record the chromatogram,and measure the responses for the major peaks:the relative retention times are about 0.97for stearate and 1.0for oleate;the resolution,R,between the stearate and oleate peaks is not less than 1.5;and the relative standard deviation for replicate injections is not more than 5.0%.NF23
Procedure—
Inject about 0.1µLof the Test solutioninto the chromatograph,record the chromatogram,and measure the areas for the peaks of the methyl esters of the fatty acids.[NOTE—The relative retention times for palmitate,stearate,oleate,linoleate,linolenate (if present),and arachidate are about 1.0,1.55,1.60,1.72,1.89,and 2.30,respectively.]Calculate the percentage of each fatty acid methyl ester in the specimen of Cocoa Butter taken by the formula:
100(ri/rs),
in which riis the response of each peak;and rsis the sum of the responses of all of the peaks:the percentages of palmitate,stearate,oleate,linoleate,linolenate (if present),and arachidate are in the ranges of 23to 30,31to 37,31to 38,1.6to 4.8,0to 1.5,and 0to 1.5,respectively.
Iodine value á401ñ:
between 33and 42.
Saponification value á401ñ:
between 188and 198.
Organic volatile impurities,Method IVá467ñ:
meets the requirements.
Auxiliary Information—
Staff Liaison:Catherine Sheehan,B.Sc.,Scientist
Expert Committee:(EMC)Excipients:Monograph Content
USP28–NF23Page 2990
Pharmacopeial Forum:Volume No.30(1)Page 207
Phone Number:1-301-816-8262