tno u;;e of 25- or 50-pouiid cartons is prec.Ludod. V/oin:hliif5 and packafjinc 

 of tho ^-pi^i-ind carton.'j requires a f^reat deal of hand labor vnich ifj not 

 alvjays available nb sea. 



Blast freeaing requires less space for I'roeainc compartments. 

 Tlie method, hovjover, has the potential disadvantage that snrimp m-uy b3 

 cjvibjuctod to deliydration, a condition cominonly referred to as 'freaaer 

 bm-ii ' . 



Where blast freezers are used, the freezing process is 

 accumplisned by exposure of the shrimp to x'apidly rroving, intensely 

 cold air ^jnicn is usually obtained from a bloxjer tiirough coils chilled 

 by a rofripei-ant such as armnonia or "Freon". The sl'iriinp ordimirily 

 are packan;ed in 5'Pound cartons placed on racks below deck and frozen. 



In one instance a blast freezer installed in the fall of 

 IS^Sli on board a shrimp vessel cost approximately iii;20,000. Amortization 

 of investmeiit, cost of upkeep, and life of equipment must be considered 

 in determining the economic advantage to be obtained from an Installation 

 of this sort. The approximate savings by the equipment ajnountecl to (1) 

 ^1-2,500 annually on ice otherwise required for chilling, (2) an additional 

 incCiiio of approximately five cents per pound (seven cents premium price 

 loss two cents additional packaging and handling charges) for the siu'imp 

 fivjaen on board vessel. Additional economies resulted from the avoidance 

 of downgrading often applied to fresh shrimp, lower freight costs, and 

 the eliriiination of time normally lost in running to the transport vessel 

 for ti'ansfer of the shrimp at sea, A furtlier advantage TJas tne length- 

 ening of the trips. Trips of the vessel prior to the installation 

 ordinarily xjoro of IS to 50 days' duration. The first two trips after 

 conversion were 88 and 89 days respectively. In addition, tne vessel 

 1,'as able to freese the catch of its sister ship and thorcby increase 

 tiio length of tlia trips of ttot vessel from about h5 to 79 days. 



In the immersion pi*ocos3 the tinriiup are neaded, ^JashGd, and 

 individually frozen in a sugar-salt solution in a deck tanlc, then pack- 

 aged in 2$'or 50-pound cartons, and stored in a holding room boloxj dock. 

 This system has the same Inherent savings as the blast and plate freei^e 

 systems: the problem of quality deterioration of iced slirimp is elxmi- 

 natud, proaact can be sold at a premium price, and longer more efficient 

 trips can bo made. In 1955 the equipment for an limnersion freezer in- 

 stallation sold for $9,5O0 f .o.b. Savannan, Georgia; the installed price 

 vjas in the neighborhood of .Iflli^OOO. The system, because of its cuiapact- 

 neiij and fiuor pi-oblems oncDuntcred in iiiaintenrinca, \na judgod aa probably 

 thcj bost yot devdiloped for sioall vessels, (see figure II - 22) 



Navi?yttioail and Fi5hl n;< Aids 



Electronic in3trimi£.its aboard fishing vessels usually serve 

 botn as navigational and as flslilng aids. Thoy guide the fisncmian 



96 



