DIFFERENT KINDS OF CHEESE AND THEIR CLASSIFICATION. 243 



that is, a hot iron having a flat surface is run over them in order to give 

 them a horny surface, or they are smoked in the smoke of firewood. In 

 these operations, the object aimed at is to attempt to improve the appear- 

 ance of the cheeses, and also their keeping qualities. 



Small soft cheeses, with oily surface, which possess a sharp smell, are 

 packed in tinfoil. The covering of tinfoil gives to the cheese not merely 

 a better appearance, but facilitates the keeping of it, and makes its retail 

 sale pleasanter, since it keeps the soft cheeses firm, and retains the pene- 

 trating odour. As, however, the tinfoil used in commerce often contains 

 as much as 20 per cent of lead, the question arises as to whether the packing 

 of cheese in tinfoil containing a large quantity of lead does not threaten 

 the health of the consumer. Experiments carried out on this subject, have 

 proved that cheeses which have been packed in tinfoil, containing a high 

 percentage of lead, only contain lead on the outer portion of their rind, and 

 that the percentage of lead in this portion is only -5 per cent, and that a 

 short distance inwards from the rind no lead can be detected. If, there- 

 fore, the precaution be taken not to eat the rind of cheeses which have 

 been packed in tinfoil, there is no ground for fear on this account. 



A sample of tinfoil has been found to contain 



Tin, 96-21 



Lead, 2'41 



Copper, -95 



. Nickel, -29 



Iron, -09 



99-95 



In Algau, in Bavaria, it is customary, in the case of brick-shaped 

 cheeses, to pack them when they are only a quarter ripe, the cheese being 

 first wrapped up in firm unglazed paper, and then in tinfoil. A skilled 

 cheese-maker can wrap up in an hour 80 to 100 separate brick-cheeses in 

 tinfoil. 



The preparations for hastening the manufacture of sour-milk cheeses, 

 introduced by Trommer in 1846, which consisted in treating the curd with 

 ammonia, carbonate of ammonia or soda, in order to give to the fresh cheese 

 the appearance of old and regularly-ripened cheese, need only be mentioned 

 here as an historical curiosity. 



119. The Different Kinds of Cheese and their Classification. Of 

 the very large number of different cheeses now known, a not incon- 

 siderable portion were known to the nations of antiquity. Fresh 

 whey and fresh watery cheese were partaken of in very early times, 

 several thousand years before the beginning of our era. Certain 



