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of volatile acids of the fatty series, and forms readily in all milk 

 products, especially those which are prepared with the aid of flour. 



Taste : More or less sweet, mainly derived from the admixed 

 condensed milk. 



External normal appearance : Most foods appear as a more 

 or less flne powder of a whitish to yellow color ; lately they have 

 also been brought into the shape of tablets, obtained by the appli- 

 cation of high pressure. 



Abnortnal appearances : Vegetable mould and animalculse 

 are met with only in very old and carelessly exposed articles, 

 especially when it had been packed in defective boxes, or when it 

 had been kept in damp places. 



Microscopical Examination. 



This aims to recognize : 



1. The general structure of the powder. 



2. The butter globules of the milk. 



3. Probable abnormal qualities. 



The bulk of these milk-foods consists of carbohydrates which 

 appear differently, according to their preparation previous to the 

 admixture of the milk. They are either used in the crude state, or 

 after being diastasized or baked. 



Without going into the details of the questions of physiology 

 and chemistry of starch, it will be well to give a few facts relating 

 to this substance. 



Starch heated with much water loses, already at a temperature 

 of from 60 to 70° C, its peculiar characteristics by which it can, 

 otherwise, easily be recognized under the microscope. Some kinds 

 of starch show after careful roasting plainer and more easily recog- 

 nizable properties than they possess when they are in the raw state. 

 In examining a starch we can, therefore, use this process for the 

 determination of their origin. The starch granules in bread gener- 

 ally retain their characteristics. 



Careful heating to 100° 0. increases the size of the granules. 

 The structure and the navel become more distinct, and the shape 

 becomes more round. Under the influence of a temperature of 

 150° C, most granules burst, and then the characteristic structure 



