104 MADRAS FISHERIES BULLETIN VOL. XIII, 



or frying, negligent and ugly, irregular packing, insufficient or 

 excessive exhaustion and processing ; to which may be added 

 rusty and coarsely soldered cans and ugly or dirty labels. 



144. Bacterial or chemical action within the can. — This malady 

 refers to cans that have been well packed with good material and 

 with apparently correct results as regards hermetical sealing, and 

 yet go bad mysteriously, sometimes quickly but more often after 

 a considerable period, as in the store room. These are probably 

 due to some occult bacterial or chemical action which cannot be 

 detected without the aid of the bacteriologist and chemist, and in 

 India this is seldom available ; the canning bacteriologist is 

 somewhat of a specialist, and, if available, the facilities for 

 submitting cans and obtaining a useful opinion are few. Defects 

 such as the discoloration of fish, especially prawns, may be due 

 not to bad cannery treatment, but to inherent causes such as the 

 constituents of the fish (e.g., possibly sulphur) affecting or affected 

 by the material of the container. This is dealt with elsewhere; 

 see ' container ' and ' prawns. ' 



