S6 U. S. BUREAU OF FISHERIES 



And, third, toward packing the product so it will present a pleasing 

 appearance when removed from the can. During the conduct of this 

 work, the following aquatic foods have been experimentally canned: 

 Fish flakes; fish cakes; fish chowder; fish balls; fish pastes; mullet, 

 plain, in tomato sauce, and spiced; mackerel, plain, in tomato sauce, 

 spiced, and smoked; amberfish; salmon, plain and spiced; grouper; 

 squeteagues; croaker; eels, plain and pickled; catfish; carp, plain and 

 spiced ; lake trout; whitefish ; shrimp; crab meat; clams, whole, minced, 

 and chowder; oysters; alewives; and shad. 



In canning the crab meat, particular emphasis has been placed on 

 developing a method for commercial application in canning meat taken 

 from the blue crab caught along the Atlantic coast. Attention also 

 has been given to packing fresh crab meat in various ways in cans for 

 shipment to market under ice. 



To date, successful methods have been developed for the home can- 

 ning of salmon, shad, mackerel, lake trout, whitefish, mullet, and for 

 canning certain types of spiced fish and fish chowder. These methods 

 may be adapted with modifications to the commercial or semicom- 

 mercial canning of these species. A report on this work has been 

 recently issued by the Bureau and copies are available on request. 



As regards the canning methods developed, it has been definitely 

 shown that to obtain sterility in the final product, when canned in the 

 home, it should be packed in no container larger than a no. 2 tin can 

 or pint glass jar, and the product while in the container should be 

 cooked in a steam-pressure retort equipped with a thermometer as 

 well as a pressure gage. 



BACTERIOLOGICAL INVESTIGATIONS 



In the development of improved processes and methods for the 

 preservation, storage, and other handling of aquatic products, the 

 investigator is constantly confronted with the problems of bacterial 

 spoilage. Therefore, in various of the investigations discussed 

 previously, bacteriological studies are correlated with chemical and 

 engineering studies. For instance, bacteriological examinations were 

 made of the experimental packs of canned aquatic foods to determine 

 which processes produced sterility, on the keeping qualities of fresh 

 mackerel packed in ice, in determining the preservative value of 

 smoke, on the tests developed for determining the relative freshness 

 of fish, and others. 



During the latter part of the past year, a special cooperative 

 bacteriological study was begun to determine the effect of antiseptics 

 in ice on the keeping quality of fresh haddock when packed in such 

 ice for temporary preservation. This study is still in progress. In 

 addition, a bacteriological investigation is in progress on disinfecting 

 sponges used in the household. This will be discussed in the following 

 section. 



DISINFECTANTS FOR SPONGES 



Sponges used in the household for cleansing purposes may be a 

 possible medium for the spread of infectious diseases among the mem- 

 bers of the family. In view of this situation, the sponge industry has 

 been meeting with consumer resistance in the purchase of sponges. 

 In order to learn whether this resistance was justified, and if so, what 



