BACTERIOLOGY OF SARDINES 183 



SESSIONAL PAPER No. 38a 



PRESENT INVESTIGATION. 



The investigation herein described of the " Bacteriology of Swelled Canned Sar- 

 dines " has been undertaken on behalf of the Biological Board of Canada. The work was 

 commenced in the summer of 1916 at the Marine Biological Station, St. Andrews, 

 N.B., and has since been continued in the laboratories at the college. To the canners 

 the appearance of " swells," as they are termed, in the cases of canned fish sent out 

 from the factories is a matter of considerable concern. The desirability of under- 

 taking experimental work in the hope of eliminating any risk of cans developing the 

 swelled condition, occurred to the principal of Macdonald College, Dr. E. C. Harrison, 

 in the summer of 1915. At that time Dr. Harrison was engaged at the marine station, 

 St. Andrews, in the examination of haddock attacked by a bacterial disease, and it was 

 while conducting this investigation that the problem discussed herein came under 

 his notice. 



The matter was brought to the attention of Dr. A. B. Macallum, secretary of the 

 Board, and in due course it was my good fortune, on the recommendation of Dr. 

 Harrison, to be asked to take up the work. The procedure to be .adopted was left 

 entirely in my own hands. Dr. Macallum, and Dr. A. G. Huntsman, curator of the 

 marine station at St. Andrews, have throughout given me every encouragement, and 

 the greatest possible help in every way which seemed likely to assist in the elucidation 

 of the problem. 



On arriving at the station in July, the necessary arrangements were made by Dr. 

 Huntsman enabling me to visit a number of the New Brunswick canning factories. 

 Later it was made possible for us to visit several of the largest plants operating in the 

 State of Maine. I was thus brought into close touch with the industry of canning as 

 a commercial undertaking, had exceptional opportunities of seeing the methods of 

 packing as generally adopted, and accumulated a store of information as a result of 

 discussions with the canners themselves. Eactories were visited which were engaged 

 in the canning of herring, sardines, haddock, and c^ams, respectively. It is hardly 

 necessary to say that the sardines of New Brunswick and the State of Maine are small 

 herrings. It was apparent that the canning factories were principally concerned in 

 the packing of sardines; and while both during the summer and since returning to the 

 college, swelled cans of sardines, herring, haddock, lobster, and shrimps have been 

 gradually accumulating, the work has up to the present been confined entirely to sar- 

 dines and possible influences affecting the same. After nine months' work, I find 

 that I have been able to do little more than touch the fringe of the problem, considered 

 as a whole. The report here presented therefore is principally concerned in recording 

 the work accomplished up to the present, such conclusions as it is legitimate to draw 

 at this early stage, and such information as to methods and media used in the labora- 

 tory as will make the work of some service to the continuance of the investigation. 



Under the circumstances I do not propose to enter into a detailed description of 

 the equipment, methods of treatment and system of packing of the fish, and general 

 procedure of the factories engaged in the canned fish industry; such will be more 

 appropriate when the work has progressed to a more advanced stage. The one phase 

 of the canning process of which brief mention must be made at this point is the tem- 

 perature employed in the so-called sterilization of the cans when packed and finished. 

 As the most common size of can produced from all the factories is one weighing from 

 3 to 4 ounces, the temperatures given shall be those applied to cans of this size. 



In the majority of the factories visited, the cans are immersed in baths of boiling- 

 water for a period of l-|-2 hours. That completes the heating process. Briefly the essen- 

 tials of the treatment of the fish — which have been salted in the boats as taken from 

 the weirs, — on arrival at the factory is as follows : immersed in a mixture of sea-water 

 and salt for 1 to 1| hours; spread on racks, termed flakes, in thin layers, and for 10 



