Section V, 1922 [101] Trans. R.S.C. 



XVI. The Red Discolouration of Cured Codfish 



By 



F. C. Harrison, D.Sc, F.R.S.C, and Margaret E. Kennedy, M.Sc, 

 Bacteriological Laboratory, Macdonald College, Que. 



(Read May Meeting, 1922) 



CONTENTS 



I. The Codfish Industry " 101 



II. Historical Resume 102 



III. The Present Investigation 114 



1. Description of Colour on Salted Fish 114 



2. Direct Microscopical Examination 115 



3. Isolation of Causal Organism 116 



4. Morphological Characteristics 120 



5. Cultural Characteristics 125 



6. Viability 133 



7. Pathogenicity 134 



8. Other Organisms Isolated from Reddened Codfish and 



Able to Grow in High Percentages of Salt 134 



9. Inspection of Curing Establishments 137 



10. Salt the Cause of the Red Discolouration 141 



11. Remedial Measures 148 



12. References 149 



I. The Codfish Industry. 



The codfish industry provides for the Dominion of Canada a 

 return of no inconsiderable amount — one which surpasses that 

 derived from all other fish enterprises, salmon alone excepted. In 

 figures, the total quantity of cod caught and landed during 1919 was 

 2,606,770 cwts., which, when marketed, yielded a return of $9,987,612. 



The fish is marketed in a variety of forms, such as fresh, green- 

 salted, smoked fillets, smoked, boneless, canned, but by far the 

 greatest amount as dried cod. From the total catch of cod in 1920 

 823,000 cwts. was sold as dried, green-salted, or boneless, and the 

 quantity exported up to the end of the fiscal year ending March 31st, 

 1921, was 713,000 cwts., providing a return of $5,169,266. 



Practically all of the dried fish prepared in Canada is exported. 

 About one-eighth of it finds a market within the British Empire, 



