4 U. S. BUREAU OF FISHERIES. 



chloride and 95.3 parts of pure salt required five days to penetrate 

 fish to the exteijt that pure salt did in three daj'S ; and the same salt 

 required nine days to penetrate as far as pure salt did in four and 

 one-half days. It was found that salt applied dry to fish penetrated 

 fish as deeply in five days as saturated brine did in eight days. It 

 was found that blood spoiled at a lower temperature than fish flesh, 

 and that fish containing blood, roe, and milt spoiled at about 65° F., 

 while thoroughly cleaned fish could be salted successfully at 90° or 

 even 100° F. It remained, therefore, only to take advantage of these 

 principles and to apply certain facts already known from other 

 sources to hasten penetration of salt and retard decomposition of 

 fish until they are preserved, 



PRINCIPLES OF IMPROVED PROCESS. 



The principles will now be taken up and discussed in such a way 

 that by following in detail the method outlined it is believed any 

 person can carry them successfully into practice. The principles 

 are: 



1. Careful handling of fish before salting. 



2. Thorougli cleaning, especially removal of all blood. 



3. Use of salt of a high degree of purity. 



4. Application of salt in the dry condition. 



To these should be added — if the fish are to be stored for any 

 considerable length of time — storage of fish in lirine. (There is 

 considerable doubt of the feasibility of storing salt fish in veiy warm 

 climates ; until this subject is investigated it seems advisable to hold 

 only in cool storage.) 



These principles are known, at least in part, to many experienced 

 salters of fish, yet the combination of them all is rarely or never fol- 

 lowed. The great difference that is made in the quality of salt fish 

 by following them will l)e readily observed upon comparing the 

 product with that of ordinary processes. 



1. Careful handling or fish before salting. — Two precautions 

 are j^articularly important under this head, namely, to avoid bruises 

 and to avoid waranth. Bruises promote decomposition of fish in the 

 same way that they cause fruits to rot. Therefore, fish should not 

 be forked, walked on, squeezed when taken from nets, nor packed deep 

 in boats, boxes, or barrels, and c;ire should be exercised to see that 

 they are not crushed or bruised by large chunks of ice. Warmth, as 

 every fisherman knows, hastens decomposition. It is best to put the 

 fish in finely crushed ice immediately after capture, but if not so 

 treated they should be kept as cool as possil)le and should be salted 

 with tlie least possible delay. It is well to remember that fish are of 

 about tlie same temperature as that of tlie water from which they 

 come, and therefore fish taken from warm water should be handled 

 more expeditiously than those from cold water. Fish should be 

 shielded from direct sunlight and should not be allowed to dry, 

 as the skin shrinks and loses its luster if dried. 



2. Thorough cleaning, especially removal of all blood. — It has 

 been found in the case of river herring that blood spoils at a much 

 lower temperature than flesh. These fish can be salted at from 90° to 

 100^ F. or higher if the blood is all removed, while those containing 



