134 DESCRIPTION OF IMPORTANT FISHERIES AND THEIR PRODUCTS 



sequent operation the fish passes a vacuum apparatus which removes the 

 viscera by suction. The cleaned fish is then flumed into smaller holding 

 tanks. From here the fish finally is conveyed to the packing table where 

 cannery workers place the sardines into their requisite cans. In other 

 instances, the fish is passed from the cutting table directly into fully 

 automatic filling machines. 



After the can is filled with sardines, it is conveyed to the exhaust box. 

 The exhaust box consists of a slowly moving, broad, metallic conveyor 

 belt surrounded by a hood into which live steam is injected. The speed 

 of the conveyor belt is so regulated that the open, filled sardine cans 

 are heated up to a temperature that will expell the trapped air in the 

 can and coagulate and shrink the fish protein, thereby releasing some of 

 the natural juices of the fish. Sometimes smoke is introduced into the 

 exhaust box, thereby imparting a light, smoked flavor to the canned 

 product. This is done, for instance, when the so-called 6-ounce tinapa 

 sardines in tomato sauce are passed through the exhaust box. The tem- 

 perature inside the exhaust box, being open to the atmosphere at both 

 ends, can, of course, not exceed 212°F and often averages from 200 to 

 210°F depending upon circumstances. The speed at which the cans pass 

 through the exhaust box determines their final exit temperature. The 

 speed at which the conveyor takes the various can sizes through the box 

 can, therefore, be regulated so that small cans of fish spend shorter time 

 in the exhaust box than the larger cans do. The final temperature of the 

 open can of fish upon leaving the exhaust box should be around 145°F. 



After a stay of 10 to 25 minutes (depending upon size of cans) in the 

 exhaust box, the cans move out on the line and are tilted to draw off 

 the free natural juices of the fish. After this, brine, tomato sauce, mustard 

 sauce, or oil is added to the can before it goes to the automatic seaming 

 machine for sealing. From the sealing machine the cans move through a 

 mechanical washer that removes any particles of fish or oil or sauce which 

 may cling to the surface of the tin can. From the washer the cans drop 

 into a steel cart of circular cross section made of perforated steel plate 

 in which the sealed, washed cans are carried directly to the retorts for 

 sterilization. 



Styles of Packs. The styles for the processing of the California sardine 

 have undergone many changes and simplifications during the past dec- 

 ades. The several steps used earlier by California sardine canners, involv- 

 ing brining, hot or cold smoking, and oil frying (processes which are still 

 in use in other countries), have either been greatly modified or eliminated 

 altogether. These changes in modes of processing, dictated in part by 

 economic considerations, have resulted in a canned sardine product which 

 naturally differs from imported sardines. At the moment, the California 



