MASKING UNDESIRABLE FLAVORS IN FISH OILS" 



GiSELA JELLINEK" AND MAURICE E. STANSBY' 



ABSTRACT 



The odor of fish oil used medicinally may require masking by flavoring materials. During a search 

 for suitable masking materials, fresh, specially refined menhaden oil having a minimum of flavor was 

 stored with and without added flavoring materials for 5 days at 75° F and for longer periods at sev- 

 eral lower temperatures. In initial preliminary screening tests with 66 diff'erent flavoring materials, 

 the masking of rancid or other unpalatable flavors developing in the stored oil was evaluated by a 

 small panel. In later tests, a large consumer-type panel consisting of untrained laboratory personnel 

 was used to determine the preference for the flavors of those materials that worked best in the screen- 

 ing test and that were of a type approved by the U.S. Food and Drug Administration for use in foods. 

 Several flavoring materials showed promise, particularly those having the flavor of root beer, lemon, 

 wintergreen (methyl salicylate), and wild cherry. 



When fish oil is used medicinally — for example, 

 as a cholesterol depressant or as a source of 

 vitamins — the presence of "fishy," rancid, or 

 other flavor components may make it unpalat- 

 able. One way of overcoming this problem is 

 to add some flavoring material that will mask 

 the undesirable flavor. It is important that the 

 added flavor be one that is pleasing to most con- 

 sumers so that we do not merely substitute one 

 undesirable flavor for a slightly more undesir- 

 able one. The aim of this work therefore was 

 to find flavoring materials, approved for food 

 use, that would adequately mask the unpleasant 

 flavor components developing in stored men- 

 haden oil (the fish oil produced in largest 

 quantity in the United States) and that would 

 also have a flavor pleasing to most customers. 



We carried out this study in two experiments. 

 In Experiment 1, reasonably palatable men- 

 haden oil refined by a special technique was 

 stored for 5 days at room temperature with and 

 without added flavoring materials. A small 

 trained panel was used to determine the effi- 

 ciency of over 66 different flavoring materials 



' This research was carried out as a cooperative pro- 

 gram between the University of California Food Science 

 and Technology Department, Davis, Calif. 95616, and 

 the Bureau of Commercial Fisheries (now National 

 Marine Fisheries Service) Technological Laboratory, 

 Seattle, Wash. 98102. 



" Mozartstrasse 15, 69 Heidelberg, Germany. 



' National Marine Fisheries Service Pioneer Research 

 Laboratory, Seattle, Wash. 98102. 



in masking the developing undesirable flavor 

 components in the stored oil. Then, in Exper- 

 iment 2, those materials giving the best masking 

 action, excluding any not approved for use with 

 food, were further tested by a larger consumer- 

 type panel for hedonic rating of the different 

 flavors resulting from adding the selected flavor- 

 ing materials to the oil before it was stored. 



EXPERIMENT 1 -MASKING TESTS 



The first series of tests were set up as a rapid 

 screening of many flavoring materials to see 

 which ones best masked the undesirable off fla- 

 vors that develop in stored menhaden oil. At 

 this stage, no consideration was given to indi- 

 vidual preference for the flavor additive, which 

 was investigated in Experiment 2. 



MATERIALS 



Menhaden oil was specially refined by a com- 

 bination of clay bleaching, molecular distillation, 

 and treatment with massive quantities of silica 

 gel (Stansby and Jellinek, 1965). This treat- 

 ment yielded an oil that was free of fishy and 

 rancid flavor components but that still retained 

 some small burnt flavor. 



Sixty-six flavor additives that were screened 

 initially included synthetics and isolates. 



Manuscript received August 1970. 



FISHERY BULLETIN, VOL. 69, NO, 1, 1971. 



215 



