THE BOTTOM FISHERIES 77 



onds; the oil is generally held at temperatures close to 400°F. In such 

 an operation about 2000 pounds of fish sticks can be processed per hour. 



Either a melted hydrogenated fat or a liquid vegetable oil is employed 

 for the cooking, and each possesses some advantages and disadvantages. 

 The liquid vegetable oils, for example, provide a very uniform coating 

 with less tendency for solidifying into irregular patches than may occur 

 with hydrogenated fat. On the other hand, use of liquid vegetable oils 

 results in somewhat shorter storage life than is obtained with hydro- 

 genated oils. There is sometimes a slight flavor preference initially when 

 the liquid vegetable oil is employed. Liquid vegetable oils are used in 

 most installations. 



The oil is heated either indirectly in a heat exchanger or directly by 

 oil or gas flame under the cooking chamber. In a properly designed sys- 

 tem, the oil volume in the cooker is kept low in relation to the input of 

 fish sticks. Oil losses, through adsorption on the sticks, are great enough 

 so that a complete oil change takes place about twice a day. Thus, no 

 significant breakdown of the oil occurs and only rarely is it necessary to 

 discard oil. 



As has been mentioned, the choice of breading compound, in part, 

 determines the color of the cooked stick. Another variable influencing 

 color is the length of the cook — longer cooking time resulting in darker 

 colors. 



During the cooking of fish sticks a loss in moisture content takes place, 

 yet the sticks do not lose as much weight as that of the moisture which 

 is lost. This is caused by a pick-up of some oil during the cooking. The 

 quantity of oil adsorbed depends both upon the length of the cook and 

 upon the characteristics (porosity, size of crumbs, and composition) of 

 the breading compound. Thus, the yield is an empirical matter controlled 

 by several factors which must be worked out for each individual operation. 



Considerable breading may be shaken loose from the sticks as they 

 pass through the cooker. These crumbs soon darken and, unless promptly 

 removed by continuous filtration, will adhere to other sticks, giving an 

 undesirable appearance and, in time, promoting hydrolysis of the oil. 



Packing and Freezing. Before packaging cooked fish sticks, it is neces- 

 sary to cool them to a temperature between 90 and 100°F; otherwise, 

 quality will be impaired. In batch operations the sticks may simply 

 remain on trays in moving currents of air until the desired temperature 

 is reached. Use is made in continuous operations of more elaborate cool- 

 ing involving conveyer belts passing through tunnels through which 

 refrigerated air is circulated. Fish sticks are packaged by hand into car- 

 tons which, if for consumer markets, generally contain eight or ten one- 

 ounce sticks. The cartons are often given an overwrap, and the contents 

 are then promptly sent to the freezer to be refrozen. 



