CANNING SARDINES 167 
TaBLeE 23.—Calculated fish-oil content of fry-bath oil 
{Four-pound units fried; oil content kept at 12 aeareay removing accumulated excess after each 
unit is fried 








Pounds 
sardine 
Baeeds Calculations oil in 12 
pounds of 
fry-bath oil 
(0.180) 12.0 
4 12. 040X x = 0. 177 
12.180 12.040 
(0.177+0.18) 12.0 
8 12. 040X x = . 302 
12. 180 12. 040 
(0. 352+0.18) 12.0 
12 12. 040X x = 524 
12. 180 12. 040 
(0. 524+0.18) 12.0 
16 12. 040X Xx = . 694 
12. 040 12. 040 


The sardine-oil content of the frying oil remaining after 800 pounds of sardines 
had been fried per 12 pounds of oil used (Bath I, second run of frying experiments, 
Tables 15 and 16), was 45 per cent, being calculated from the iodine numbers of 
the remaining oil and the pure constituents. This value is low because oxidation 
changes. took place to a considerable extent, which lowered the iodine number, 
and this in turn lowered the calculated result. This value is half the correspond- 
ing calculated value given in Table 24, but the oil diminished 21 per cent during 
the frying period. Results are not comparable, therefore, but it is shown that the 
increase of sardine-oil content of frying oil is rapid even when the sardines give up 
less oil to the bath than they remove. 
Chemical and physical changes.—Tables 25 to 28 give data on the changes that 
took place in the oils used in the frying and heating tests. 
Chemical treatment.—Chemical treatment of fry-bath oil was tried in an en- 
deavor to develop methods for improving the oil during use and for recovering 
the “old” oil. In undertaking these experiments it was realized that a suitable 
method would have to be rapid and inexpensive. A study was made of the 
various methods used in purifying oils, and the most promising of these was then 
tried on ‘‘old’’ fry-bath oil. This phase of the subject could have been studied to 
much greater extent, but the hopelessness of this line of endeavor was quite 
apparent. 
TABLE 24.—Fish-oil content of oil remaining in Bath I, second run of frying tests, 
after frying, March 10 


’ Iodine 
Oil number 
Sardine? 225225 ee 160. 0 
Pure? Crisco.) 2 ee 74. 2 
Bryne Ouse yes Ser Tee 113.0 

gis e300) (11G0= 7419): av AbhES® 
Calculation: —(160.0—74.2) =45 per cent sardine oil. 
