372 DETECTION OF ADULTERATIONS 



Kinds of Adulterants Commonly Employed. — In seeking 

 out the fact and source of adulteration under the microscope it 

 will be of great assistance to know what kinds of adulterants 

 have already been found most commonly in use. A list of these 

 will now^ be given. 



Adulterants of Ground Coffee. — Roasted rye, barley, and 

 barley malt, ground peas, beans, and other legumes, pea hulls, 

 and cereals made into pulp with molasses; ground grape seeds, 

 dried, roasted, and ground figs, ground date stones, and coffee 

 already used in making coffee extract. 



Adulterants of Ground Spices. — The list of adulterants here 

 is a long one. Both inorganic and organic substances are employed. 

 The inorganic adulterants are: brick dust, coal ashes, calcium 

 sulphate and carbonate, sand and clay, chrome yellow, and 

 Venetian red. And the organic adulterants are: hulls and bran 

 of buckwheat, bran and chaff of cereals, flour, mill screenings, 

 peas, beans, and other legumes, cottonseed and linseed meal, 

 ground cocoanut cake, and other oil cakes, ground shells of the 

 cocoanut, almond, and other nuts, ground olive stones, saw- 

 dust of red sandalwood and of other woods, and dyestuffs. 



Black pepper has been adulterated more than any other spice. 

 In it has been found almost any variety of waste material capable 

 of being reduced to powder. Sometimes when the amount of 

 adulteration has been so great as to remove the natural pungency 

 very perceptibly 'cayenne pepper has been added. 



The study of adulteration in spices should h,e undertaken as 

 suggested above for ground cinnamon. When the source of 

 the spice is in seeds, as in the case of mustard and black pepper, 

 sections of seeds can be obtained by soaking the seeds in water and 

 embedding them in glycerine gum, as described on page 306. 

 The seeds can then be sectioned free-hand or in a sliding 

 microtome. 



Adulterants of Wheat Flour. — Corn flour and gypsum. 

 The starch of the corn flour is quickly detected by the angular 

 shape of the grains and the central cracks which are seen with 

 especial clearness in alcohol. For the detection of gypsum 



