FISHERY BULLETIN: VOL. 72, NO. 4 



Table 4. — Methyl ester fatty acid composition of lipids extracted 

 from the cooked breast of turkeys' fed to 8 wk of age diets 

 containing varying levels of beef fat and tuna oil writh and with- 

 out vitamin E (c?/ -a -tocopherol acetate) supplementation. 



'All groups of turkeys were fed a basal diet plus an oil supplement for 8 

 wk. Group 1 = 4% beef fat (BF), Group 5 = 2% BF + 2'7r tuna oil. Group 6 = 

 (same as 5) + 200 mga-tocopfierol acetate per kilogram. 



C22:6uj 3 increase as the amount of tuna oil in- 

 creases in the diet. Safflower oil added to Diets 7 

 and 8 seemed to reduce the uptake of these fatty 

 acids. Tocopherol acetate supplementation did not 

 seem to have any effect on the uptake of cj3 fatty 

 acids. Fatty acid distribution analyses (Table 4) on 

 lipids extracted from cooked turkey breast from 

 Groups 1, 5, and 6 show thata -tocopherol did not 

 have an effect on the relative stability of the long- 

 chain fatty acids during cooking. 

 The results of taste panel evaluations (Table 5) 



show that, while « -tocopherol supplementation 

 did not change thecjS fatty acid distribution, it 

 greatly reduced fishy flavor as judged by the taste 

 panel. Opstvedt, Nyard, and Olsen (1970) also re- 

 ported these findings. On the other hand, safflower 

 oil (used to achieve isocaloric balance) reduced the 

 uptake of Gj3 fatty acids, but there were no differ- 

 ences in flavor when compared to the flavor of 

 turkeys fed the same amount of tuna oil but using 

 beef fat for isocaloric balance. There was a strong 

 relationship between the amount ofC20:5cj3 

 and/or C22:6cxj3 and fishy flavor when no 

 a-tocopherol or safflower oil supplementation was 

 present in the diets. This agrees with the findings 

 of Neudoerffer and Lea ( 1966, 1967), Miller et al. 

 (1967a), Miller and Robish (1969), and Dreosti 

 (1970). However, a comparison of the fatty acid 

 distributions and lipid contents found by these 

 investigators with those in this experiment and 

 Experiment I, shows that the levels of C20:5u;3 

 and C22:6cd3 present when fishy flavors are de- 

 tected are higher in these experiments. We should 

 also note that the fish oils used by other investi- 

 gators contained about 2-129^ C22:6u)3,while the 

 tuna oil used in these experiments contained 32% 

 C22:6w3. 



Experiment III 



These 16-wk-old turkeys had been fed diets con- 

 taining 3^f beef fat plus Yk tuna oil and 29f beef 

 fat plus Ific tuna oil for the 2 wk prior to slaughter. 

 The control diet contained 4*^ beef fat. All turkeys 

 apparently enjoyed good nutritional health and 

 the mean dressed weight was 3,585 g. 



Table 5. — Mean' taste panel scores* and Duncan's multiple range test of mean scores on thigh and 

 breast meat and skin of turkeys fed to 8 wk of age diets containing varying levels of tuna fish oil and 

 beef fat or safflower oil with and without vitamin E {dl a -tocopherol acetate) supplementation. 



'Means connected by a common line are not significantly different at the 0.05 probability level 



^1 = no fishy flavor, 5 = very fishy. 



MM groups of turkeys were fed a basal diet plus an oil supplement for 8 wk. Group 1 = 4% beef fat (BF), Group 2 

 = 0.5% tuna oil (TO) + 3.5% BF, Group 3- 1% TO + 3% BF, Group 4 =^ (same as 3) + 200 mg/kg vitamin E(e) Group 

 5 = 2% TO + 2% BF,Group6 = (sameas5) + 200mg/kg vitamin E, Group 7 = 1%^ TO + 3% safflower oil (SO), Group 

 8 = 2% TO -^ 2% SO. 



1036 



