162 FOODS AND FOOD ADULTERANTS. 



Maize, or corn as it is commonly known, is a common adulterant. By 

 selecting particles from the ground material and crushing them the 

 character of the starch may be recognized, but in a cursory examina- 

 tion the first sign of the presence of this cereal is the discovery of one 

 of the thin outer coats of the grain which becomes detached in milling 

 and, being tough, is not readily reduced. In yello^ corn it has a pecul- 

 iar pinkish color and simple structure of longitudinal cells. One should 

 learn to recognize it from a specimen ground for the purpose. 



Rice, which in its broken unmarketable form is sometimes used as a 

 diluent, may be recognized by the brilliant appearance of the hard white 

 particles which must be picked out of the spice under a hand lens, 

 crushed, and examined as usual. Rice bran has not been met with. 



The two cereals named are the only ones which are commonly met 

 with which introduce starch. Barely clean wheat bran is added, which 

 can be recognized by its distinctive structural character, illustrated in 

 many hand-books, but which can be learned much better from an authen- 

 tic specimen, which should be soaked in chloral hydrate. 



As modified cereals, we find refuse bread, cracker-dust, and ship-bread 

 in which the wheat starch is much changed from its original form by 

 the heat and moisture of the cooking process so that at times it might 

 be confused with a leguminous starch. The softness of the particles 

 and the ease with which they fall to pieces in water reveals the nature 

 of the material. It is a common diluent. 



Oil-seed, oil-cake, and husks are very commonly used in many parts of 

 the country for purposes of sophistication. They are most readily recog- 

 nized by the peculiar structure of the outer coats of the seed. The 

 particles which can usually be found and selected with a dissecting mi- 

 croscope should be examined in alcohol or glycerine, or a mixture of 

 the two, as the outer coats of some seeds, such as mustard, are swollen 

 by water and become indistinct. The appearance of mustard hulls is 

 given on page 172, and the many varieties of the cruciferous seeds re- 

 semble it much, so that it is difficult to distinguish them, which is, how- 

 ever, not important. They are generally distinguished by the outer 

 layer of hexagonal cells, and a middle and an inner coating which con- 

 sist of peculiar angular cells, the latter much larger than the former, 

 which are the most characteristic, and should be compared with speci- 

 mens of seed of known origin. The structure of some of them is dia- 

 gramatically presented in fig. 6, from Schimper. After soaking in chlo- 

 ral hydrate the remaining interior layers are perhaps more easily made 

 out, and in some cases after moderate bleaching with nitric acid and 

 chlorate. The interior of these seeds is not blued by iodine. 



Peanut or groundnut cake is recognized by the characteristic struct- 

 ure of the red-brown coat which surrounds the seed, which consists of 

 polygonal cells with peculiar saw-toothed thickening of the walls. The 

 seed itself consists of polygonal cells, full of oil and starch granules, 

 which are globular in form and not easily confused with pepper starch. 



