INTRODUCTIONIT IS well known that turkey fat is much less stable than chicken fat. This difference in stability assumes economic importance to the extent that it is reflected in the seriously shorter frozen storage life of turkeys, and in the relative unacceptability in foods of rendered turkey fat compared to chicken fat. Investigations on the fundamental causes for this difference in stability have been made at this laboratory in order to provide a basis for the development of methods to increase shelf life of frozen poultry, particularly turkeys.Of the two recognized chemical factors governing the resistance of natural fats to rancidification, i.e., content of fatty acids of varying degrees of unsaturation and content of natural antioxidants, fatty acids have received more attention than antioxidants in most of the previous studies on poultry fat. Studies by Hilditch et al. (1934), Cruickshank (1934), Kummerow et al. (1950), Chu and Kummerow …