78 U. S. BUREAU OF FISHERIES 
90 to 120° * and a velocity of 500 to 1,500 feet per minute, losing 
about 3 to 6 per cent in weight in the process. 
The warm air moving about the fish removes the water and 
toughens the skins so that they will not break when placed in hot 
oil or when handled during packing. Although probably it is neces- 
sary for some water to be ‘Temoved from the fish, the actual amount 
is of secondary importance. The drying conditions and the amount 
of water removed vary so greatly among canneries that it is evident 
that these factors are secondary to skin toughening.” 
Frying in oil.—This step consists of submerging the dried fish 
(held in flat wire baskets) in a vat of cottonseed or other oil kept at a 
temperature of 220 to 260° (usually about 230°) for 7 to 15 minutes 

Fic. 6.—Brining the fish. On the left are shown the tanks in which the ‘‘cut”’ fish are placed. Part 
of the dryer is shown on the right 
for large pound-oval and 3 to 10 minutes for quarter-oil fish. Frying 
usually is considered complete when the backbone can be pulled out 
easily and shows no redness. Considerable water is cooked from 
the fish. Much of this is vaporized, but some settles and mixes with 
the water under the steam coils, carrying with it soluble extractives 
from the fish. The heat also renders some oil from the fish, which 
mixes with the cooking oil. 
The following figures show the losses in weight that took place in 
one cannery that ‘prepared small oval-sized fish for canning. The 
calculations were made on the weight (371 ounces) of ‘‘cut, * brined 
fish used for the experiment: 

12 All temperatures are given in °F. 
13 This and other matters discussed in this paragraph are considered in detail, pp.116and117. Table 9, 
p. 125, gives details on drying conditions in several plants, 
