Cherry Juice
»Cherry Juice is the liquid expressed from the fresh ripe fruit of Prunus cerasusL.(Fam.Rosaceae).It contains not less than 1.0percent of malic acid (C4H6O5).
Coarsely crush washed,stemmed,unpitted,sour cherries in a grinder so as to break the pits but not mash the kernels.Dissolve 0.1percent of Benzoic Acid in the mixture,and allow to stand at room temperature until a small portion of the filtered Juice,when mixed with one-half of its volume of alcohol,does not become cloudy within 30minutes.Press the Juice from the mixture,and filter it.
Packaging and storage— Preserve in tight,light-resistant containers,and prevent exposure to excessive heat.
Labeling— The label states the Latin binomial name and,following the official name,the part of the plant source from which the article was derived.
Identification— Add lead acetate TSto 5mLof Juice until the mixture,when filtered,gives no further precipitation with the lead acetate solution.Filter,and to the clear filtrate add 5mLof sodium oxalate solution (1in 10)to remove the excess lead.Filter,add 5mLof alkaline cupric tartrate TSto 5mLof the clear filtrate,and warm:a red precipitate is formed.
Specific gravity á841ñ: between 1.045and 1.075.
Refractive index á831ñ: not less than 1.350.
pHá791ñ: between 3.0and 4.0.
Residue on ignition á281ñ: between 0.35%and 0.55%.
Arsenic,Method Iá211ñ: 0.3µg per g,the Test Preparationbeing prepared as follows.
Test Preparation— To 10mLin a Kjeldahl flask add 5mLof nitric acid and 5mLof sulfuric acid,and heat the mixture until the volume is reduced to about 5mLand the color becomes brownish or black.Add a small portion of nitric acid,and continue the heating,adding small portions of nitric acid as often as browning recurs,until the organic matter is destroyed,and dense,white fumes are liberated.Dilute the solution with about 10mLof water,add 200mg of ammonium oxalate,and continue the heating until dense,white fumes again are evolved and the solution is colorless to pale yellow.Cool,cautiously add water to make 20mL,and mix.
Lead á251ñ—
Test Preparation— Add 1.0mLof Juice to 10mLof nitric acid in a 250-mLconical flask,and boil for 5to 10minutes.Cool in an ice bath,and transfer to a separator with the aid of 5mLof lead-free water.
Procedure— Proceed as directed in the chapter,except to use 15mLof Ammonium Citrate Solution,500µLof Hydroxylamine Hydrochloride Solution,and 3mLof Potassium Cyanide Solution:not more than 5µg per mL.
Limit of nonvolatile residue— Evenly spread 5.0mLover the bottom of a tared half Petri dish,and place on a steam bath for 1hour.Dry in a vacuum desiccator over silica gel for 16hours:the weight of the residue is not less than 500mg.Not more than about 9.5%is found.
Limit of volatile acids— Distill 25mLof Juice with steam to obtain 100mLof distillate,add phenolphthalein TS,and titrate with 0.10Nsodium hydroxide:not more than 1.5mLis required.
Assay for malic acid— Place 10.0mLof Juice in a 125-mLflask,and add 1g of calcium carbonate.Heat on a steam bath for 15minutes,mixing occasionally,and pass through a filter.Wash the filter with five 5-mLportions of water,and to the combined filtrate and washings add 1mLof 6Nammonium hydroxide and 15mLof ammonium oxalate TS.Heat on a steam bath for 15minutes,pass through hardened filter paper,and wash the flask and the filter with five 5-mLportions of a solution prepared by mixing 1mLof 6Nammonium hydroxide with 49mLof water.Puncture the filter paper,and wash the precipitate into the same flask by means of hot water,followed by 30mLof 12Nsulfuric acid.Heat the solution to 80,and titrate with 0.1Npotassium permanganate VS.Each mLof 0.1Npotassium permanganate is equivalent to 6.704mg of C4H6O5.
Auxiliary Information— Staff Liaison:Claudia C.Okeke,Ph.D.,Associate Director
Expert Committee:(CRX)Compounding Pharmacy
USP28–NF23Page 2987
Pharmacopeial Forum:Volume No.27(4)Page 2793
Phone Number:1-301-816-8243