220 COAL-TAR COLORS USED IN FOOD PRODUCTS. 



AMARANTH. 

 MOISTURE. 



Determine as given under Ponceau 3R, page 215. 



TOTAL INSOLUBLE MATTER. 



Determine as given under Naphthol Yellow S, page 211. 



NONVOLATILE OR INORGANIC INSOLUBLE MATTER. 



Determine as given under Naphthol Yellow S, page 211. 



SODIUM CHLORID. 



Determine as given under Ponceau 3R, page 215. 



SODIUM SULPHATE. 



Dissolve 2 grams of dye in 100 cc of warm water in a 200-cc grad- 

 uated flask, and add 36 grams of pure sodium chlorid. Allow the 

 mixture to stand with frequent shaking for one hour, and after cooling 

 make up to the mark with a saturated salt solution. Shake the 

 mixture and filter through a diy paper; dilute 100 cc of the nitrate 

 (representing 1 gram) with water, acidify with hydrochloric acid, and 

 precipitate the sulphates with barium chlorid. The precipitate is 

 separated, washed, and ignited upon a tared platinum gooch crucible. 



HEAVY METALS. 



Determine as given under Naphthol Yellow S, page 212. 



ARSENIC. 

 Determine as given under Naphthol Yellow S, page 212. 



ETHER EXTRACTIVES. 



Determine as given under Naphthol Yellow S, page 214. 



SULPHATED ASH. 



Determine as given under Naphthol Yellow S, page 214. 



CALCIUM. 

 Determine as given under Naphthol Yellow S, page 215. 



SULPHUR. 

 Determine as given under Naphthol Yellow S, page 215. 



