Free Fatty Acids and Rancidity in Relation to Animal By-Product Protein Concentrates

Abstract

ACCURATE and trustworthy chemical methods for the evaluation of the nutritive worth of any concentrate material are eagerly sought by the producers and users of farm animal and poultry feeds.Based on experiments on poultry growth using meatscraps of high and low free fatty acid content, Schroeder, Redding, and Huber (1936) have stated that although a low free acidity of the fat gives no assurance that a meatscrap is desirable in every respect, a high acidity at once indicates an inferior product. These authors attributed the inferior results obtained with meatscraps high in free fatty acids to an inactivation of vitamins A and D rather than to the free fatty acids per se. The meatscraps termed low free fatty acid by these investigators contained 9.60 percent and 10.56 percent of fat with free fatty acid percentages of the respective fats of 5.44 and 7.46. The high free fatty acid products .