FACTORY EXPERIMENTS IN CUEING. 27 



It would seem, however, that the latter assumption is not well 

 founded, as an excess of salt above that which can be taken up by 

 the fish is used in all cases and as long as the brine is saturated it is 

 as strong for pickling purposes as it is possible to make it, and it 

 does not make any difference whether the excess above saturation in 

 a given volume is an ounce or 10 pounds. The fish handlers in- 

 variably speak of the pickle getting stronger in going from the top 

 to the bottom of the butt, and yet the salinometer will show 100 at 

 all points. It is obvious that the brine can not be stronger, for only 

 a given quantity of salt can be held in solution in a given quantity 

 of water. It is the belief of the writer that the difference in the ap- 

 pearance of the fish supposed to be due to a difference in the strength 

 of the pickle is wholly due to the effect of pressure in the butt. Un- 

 fortunately no samples were taken from the bottom of the kegs 

 to determine the effect of pressure, as its importance in connection 

 with the salting was not known at that time. 



It is the general belief among superintendents at the fish factories 

 that salt onco used in pickle, though not dissolved because of the 

 excess employed, becomes exhausted. Such salt is generally thrown 

 upon the docks to preserve the boards. This assumption is not based 

 upon good evidence. It may not be desirable to use such salt a second 

 time, but when tested by placing it in solution a salinometer will 

 show that it has lost none of its strength. 



The rate at which the abstraction of water and salting takes place 

 shows that this operation is practically completed in twenty days and 

 that three-fourths of the work goes on in the first two days. There 

 is a displacement of about 20 per cent of water in the tissues by the 

 action of the salt, and between 14 and 15 per cent is displaced in the 

 first two days. The changes proceed slowly after the third day, and 

 the custom of allowing the fish to remain from 17 to 20 days in the 

 butts to become full pickle cured is based on long experience and 

 finds full vindication by experiment. One result produced by keep- 

 ing the fish in the pickle is to harden the tissues, for although little 

 salt is taken up after the sixth day, there is a progressive hardening 

 of the tissues, and this is quite noticeable up to the twelfth day; 

 after that time the change is too slow to be measured by appearance 

 alone. 



About half a pound of salt is used to the pound of iced fish in the 

 regular course of curing the full salted fish; for export fish about 

 three-eighths of a pound is used, and for slack salted one-fourth of a 

 pound. As the cured fish contain only from 14 to 20 per cent of salt, 

 it is evident that about 33 per cent of the amount used serves as a 

 preservative while the remainder acts as a drying agent, and it would 

 sec in that improved methods might effect a marked saving in this 

 part of the process. 



