SEA-FISHERIES LABORATORY. 99 



perhaps increase the actual percentage of fat, but more in- 

 formation is required with respect to this. It also renders the 

 flesh more digestible in that it allows a certain degree of 

 autolysis, that is self -digestion of the muscle substance by 

 the action of the intra-cellular enzymes contained in the tissue. 

 It is possible that the proteid substance so altered sets free 

 fat in some form. The natural process of autolysis, which 

 would go on independently of decomposition due to bacteria, 

 would end in the production of ptomaines, but the salting 

 controls this. The flesh becomes " pasty," and savoury 

 " extractive " substances are formed. This is the rationale 

 of curing a fat-rich fish in oil as in the process of preparing a 

 sardine, and much the same thing occurs in the curing in 

 brine of herrings. It is to be noted that the curing of fat-poor 

 fish, such as cod and ling, by salting and drying differs materially 

 from the process above indicated. 



The most successful (both commercially and economically) 

 exploitation of such a fishery as the summer-herring one in 

 the Manx waters is undoubtedly the curing, in various ways, 

 of the great bulk of the fish caught. The processes of distribu- 

 tion can thus best be controlled, the product becomes a better 

 one from the food point of view, and local industries are 

 established. A clamant need of the present time, and indeed 

 of normal times, is the curing of summer-caught herrings for 

 consumption in the winter months, when fat-rich foods are 

 more useful than in the warmer months. 



It will be seen from Mr. Scott's report, that young 

 herrings and sprats, caught in the winter, have a much smaller 

 proportion of fat than these summer-caught herrings. Many 

 of these fish are cured in the sardine form, but it is to be noted 

 that the lean winter- caught sprat is not so suitable for this 

 purpose as the fat summer herring. A very great advance 

 in the progress of the local fisheries would be made if it could 

 be discovered where these sprats, that are so abundant off 



