124 American Fisheries Society. 



fried in an oil which is largely fish oil. It can be shown 

 by calculation that under conditions which are frequently 

 paralleled commercially, the oil will be over 90% fish oil 

 after 25 hours of service. 



The use of corn oil or a hydrogenated oil such as Crisco, 

 in addition to cottonseed oil, was found to be feasible for 

 frying purposes. However, under conditions just described 

 it is evident that it makes little difference what oil is used 

 except at the first. 



The presence of varying quantities of fish oil, and the 

 action of air and heat, are largely responsible for the chang- 

 es which take place in fry-bath oil. Under existing condi- 

 tions the fish oil content of fry-bath oil is not open to con- 

 trol, but the bad effects due to air and heat can be lessened 

 by diminishing to a minimum the action of these factors. 

 Fry-baths should be constructed so as to offer minimum 

 exposure of oil to the action of the air. By using the small- 

 est possible amount of oil for the purpose, replacements will 

 be large and this will diminish the effects coming from the 

 action of the air and heat upon the oil. 



Attempts to reclaim used fry-bath oil by chemical treat- 

 ment were unsuccessful. It is not probable that a satisfac- 

 tory cheap method will be developed. 



In concluding, it may be said that although some of the 

 difficulties of frying in oil are inherent much can be accom- 

 plished by attention to the following points : construction of 

 fry-baths which use the minimal possible quantity of oil for 

 the purpose ; maximum protection of the oil from the action 

 of air and heat ; removal of frying oil to as great an extent as 

 possible from the cooked fish before canning; and more 

 frequent oil removal, using cheaper yet high quality oil. 



The second problem taken up was a study of methods of 

 preparing fish for canning as sardines. It is evident from 

 a consideration of the first investigation that some of the 

 difficulties incident with frying in oil can be materially les- 

 sened and that further study, especially upon the design of 

 equipment, offers promise, yet certain troubles undoubtedly 

 will still exist. Elimination of the necessity of frying as a 

 step in the preparaton of sardines for canning presents a 

 most desirable field for investigation. This was and still is 

 especially true in California where, at the time of planning 

 the investigation, considerable interest was evident, yet 

 little known about methods of accomplishing this end, and 

 as to how fish prepared in ways other than frying would 

 withstand storage and shipping. No commercial attempt 

 in this field had yet been satisfactory. Frying in general, 



