SOPHISTICATION AND SUBSTITUTION 143 



2. Cold-Water Treatment: 



Procedure : — Place sample gently upon surface of cold water in 

 a beaker; or shake sample in test-tube of cold water, and allow 

 to stand aside; in which case, coffee rises to the surface. Allow to 

 remain 15 minutes. 



Test: — Pure coffee, because of its oil content, does not imbibe 

 water, and floats with the exception of a few highly carbonized 

 portions, and gives little or no color to the water. Chicory, 

 caramel, and forms of burnt sugar absorb water, sink, and pro- 

 duce strong brownish-red streaks in descending; and, by diffusion, 

 tint the entire liquid. Chicory possesses 3 times the tinctorial power 

 of coffee. Roasted roots, berries, mineral ingredients, rye, corn, 

 beans, peas, lupines, figs, etc., communicate a similar coloration, 

 but less rapidly and to a less extent than chicory. Caramel gives 

 a deep brown color, and the solution has a bitter taste. Inor- 

 ganic coloring-matters in the sediment may be sought by ordinary 

 qualitative methods. 



Procedure: — Place a sample upon a flat glass plate. Moisten 

 with few drops of water. 



Test: — Pure coffee remains hard when tested with a needle. 

 Adulterants become soft. 



3. Warm or Boiling-Water Treatment: 



Procedure : — Agitate a sample in boiling water. Allow to settle. 



Test: — Genuine coffee gives a clear and limpid solution. Most 

 adulterants — because of the presence of starchy and saccharine 

 matters — yield a thick, brown, turbid, gummy liquor. 



Procedure: — Specific Gravity Infusion Test after Messrs. Gra- 

 ham, Stenhome & Campbell. Boil i part of sample with 10 parts 

 H2O; filter. Determine density of infusion at 15.5° C. 



Test: — Pure coffee-infusions, because of their almost absolute 

 freedom from sugar, as compared with cereal and root adulterants, 

 have sp. grav. of 1.00986. Most infusions of adulterants have a 

 higher value; for example, pure chicory-infusion has sp. grav. of 

 1.0282 1. 



4. Salt Treatment: 



Procedure: — Shake sample in test-tube filled with saturated 

 solution of common salt. 



Test: — Pale amber liquid; sample floats if pure coffee. Dark 



