Effects of coating kibble with chicken fat enriched with free fatty acids on digestibility and palatability in...

Complete uncoated extruded kibble was coated with a premium chicken fat spiked with 0%, 5%, 10%, 15%, or 20% free fatty acids (Oleic acid, Millipore Sigma. Burlington, MA), and 3% liquid chicken-based natural flavor. Kibbles were then utilized in oral palatability (20 dogs, 10M/10F), aromatic palatability (20 dogs, 10M/10F), and apparent total tract digestibility (36 dogs, 18M/18F). Kibble odors were analyzed by flash gas chromatography electronic nose (AlphaMOS, Toulouse, France), and SPME GC/q-TOF (MUMC, Columbia, MO). In the aromatic palatability trials, there were no significant differences in first approach (P ≥ 0.21), percent interaction time (P ≥ 0.16), or interaction ratio (P ≥ 0.94). In the oral palatability trials, there were no significant differences in first approach (P ≥ 0.26), first bite (P ≥ 0.50), percent consumed (P ≥ 0.15), or intake ratio (P ≥ 0.59). There was no significant difference in protein, carbohydrate, or dry matter digestibility (P ≥ 0.06), and no significant difference in fat digestibility between coated diets by Tukey's post hoc (P ≥ 0.09). Principle component analysis of e-nose peaks showed minimal odor changes between samples (DI = -3). Volatile analysis identified 16 compounds correlated with oleic acid percentage (r ² ≥ 0.50). Kibble coated with chicken fat containing up to 20% oleic acid did not negatively impact odor profile or palatability in Labrador retrievers.