122 BULLETIN 908, U. S. DEPARTMENT OF AGRICULTURE. 



from four to six hours. Some method of refrigeration should be in- 

 stalled on all boats used to haul the fish over long distances, thus 

 greatly extending the fishing area and bringing the fish to the can- 

 neries in a condition far superior to that of fish carried in salt. The 

 boats, both the refrigerator and the ordinary type, should be pro- 

 vided with small compartments, permitting circulation of cold air, so 

 that the fish are carried in small bulk, thus preventing the rise in 

 temperature which occurs when fish are carried in bulk, as is now 

 customary. 



Salting and pickling the fish. — An appreciable amount of nitro- 

 genous matter is extracted from fish held in salt, and an even greater 

 quantity from those held in pickle. To insure a minimum extraction 

 of material, consistent with the proper degree of salting, uneviscerated 

 fish should remain in salt or pickle not more than two hours, while 

 from 15 to 20 minutes is long enough for cut and eviscerated fish to 

 remain in strong pickle. Fish which are excessively salted or are 

 kept in brine an unduly long time lose the characteristics of fresh 

 fish. Sardines with a salt content of 3 per cent were received with 

 the most favor. The greater part of the salt remains in the skin of 

 the fish, which explains why it is so readily lost during the ste amin g 

 process. 



Drying the fish. — More attention should be paid to the drying 

 process than is now customary. Before being packed, from 5 to 8 

 per cent of the water they contain should be driven from the fish. 

 Either too little or excessive drying ruins the appearance of the 

 pack. An even, thin flaking of the fish, proper control of the volume 

 and temperature of the air in the tunnel dryers, and drying for 

 exactly the requisite period are essential for securing a high-grade 

 product. 



Packing the ^TL— Special skill and technique are necessary in 

 packing sardines. Great care must be exercised in placing the 

 small fish in the can and also in cleaning the cans. Rough treat- 

 ment of the filled cans not only tends to disarrange the contents, but 

 may dent the seams, causing leaks. 



Oiling. — Three quarts of oil to the case should be added to fat 

 fish, and 3| quarts to the case for lean fish. Time should be allowed 

 for the absorption of this amount of oil before sealing the cans. Corn 

 oil appears to fulfill all the requirements for a good pack and its 

 flavor does not mask that of the fish. Baked fish packed in corn 

 oil and fish fried in corn oil proved to be superior to fish which were 

 steamed. 



Storing the sardines. — The desirability of storing sardines at low, 

 even temperatures was demonstrated by a series of experiments on 

 the freezing and thawing of sardines. Weak solutions of ammonia 



