studies have been conducted using sev- 

 eral devices. A special xicon television- 

 type tube and various photocells have 

 been used with little success to meas- 

 ure the change in intensity of X-rays 

 emanating from the product when it is 

 exposed to a gamma ray source. Un- 

 fortunately when using these methods, 

 it was not possible to electrically de- 

 fine what little resolution was obtained. 



sanitary care exercised in the com- 

 mercial handling and production of the 

 product. There are very fewdataonthe 

 bacteriology of commercially prepared 

 fishery products. To obtain such data, 

 which may provide a basis for Federal 

 or State bacteriological standards, this 

 laboratory conducted a survey of the 

 various fishery products produced and 

 marketed in the local area. 



Figure 13.--X-ray picture showing bony structure of fish. 



Another method, that of using certain 

 photocells to scan the image appearing 

 on the fluorescent screen of an X-ray 

 unit, shows considerable promise. Re- 

 sults show that it is possible to obtain 

 re solution between medium -sized bones 

 and fish flesh. The bones in fish flesh 

 and portion samples moving at simu- 

 lated production-line speeds were 

 picked up in the form of a readily 

 discernible and reproducible electrical 

 signal on a cathode ray oscilloscope. 

 As a result of these tests, a prototype 

 X-ray bone detection unit will be de- 

 signed and constructed. This unit will 

 be used in simulated plant tests to 

 statistically define the resolution be- 

 tween fish flesh and both small and 

 large bones. 



Bacteriological Evaluation of 

 Commercially Produced Fishery 

 Food Products 



The number of bacteria in fishery 

 food products is often an indication of 

 the quality of the product and of the 



Preliminary results indicate that 

 frozen fish fillets and precooked frozen 

 fried fish products such as fish sticks, 

 portions, and scallops usually have a 

 relatively low bacterial content (aver- 

 age plate counts of approximately 

 100,000). In general, fish products pur- 

 chased by the consumer are of ac- 

 ceptably low bacterial content. 



Improved Handling of Fish on 

 Massachusetts Fishing Vessels 



The objective of this project was to 

 improve the quality of the fish being 

 landed in Massachusetts ports. This 

 work was carried out under contract 

 by the Massachusetts Division of Ma- 

 rine Fisheries and consisted of having 

 an experienced commercial fisherman, 

 referred to as a principal investigator , 

 make trips on commercial fishing ves- 

 sels in order to provide instructions 

 in the icing and handling of the fish and 

 in the maintenance of proper sanitary 

 conditions. 



Figure 14. --Haddock in ice aboard the vessel. 



