THE SHRIMP FISHERY 



169 



black banding on the shell and produces an unsightly appearance which 

 may cause customer resistance to the fresh or frozen product. Black spot 

 is caused by an oxidation-reduction enzyme system and is thus aggra- 

 vated by exposure of the shrimp to air^. It can be kept to a minimum 

 by rapid handling of the shrimp. Some fishermen dip the shrimp in dilute 

 solutions (13^^ per cent or less) of sodium bisulphite before packing them 

 in ice^. This serves to inhibit the formation of the black spot. This prac- 

 tice is not universally popular with buyers, however, since it removes 



Figure 12.2. With catch nearly sorted from one drag, the worker is surrounded by 

 carpet of shrimp. {"Fish Boat," H. L. Peace Publications.) 



SL danger signal which some of them use to warn of shrimp which have 

 been mishandled and which may be partly spoiled. Black spot can be 

 reduced by short drags, beheading on the boat, thorough washing, and 

 rapid icing^^ 



At the dock the shrimp are unloaded into wash tanks which serve to 

 clean them and separate them from the crushed ice. If they were not 

 beheaded on the boat, this operation is now performed. Sometimes the 

 shrimp are graded for size at this point. The shrimp are packed with 

 crushed ice, 100 pounds of tails to the box, or iced in bins in refrigerator 

 trucks. 



