Optimization of key aroma compounds for dog food attractant

Although several investigations devoted to dog food attractants (DFAs) have been conducted, these studies fell short in identifying the key aroma compounds that could improve the palatability performance of pet foods. The aim of this study was to identify the key aroma compounds in the DFA using headspace-solid phase micro-extraction, gas chromatography-mass spectrometry and Partial Least Squares Regression (PLSR) analysis. Seven DFAs with different aroma compounds obtained by Maillard reaction were employed in the study. A total of 53 aromatic compounds were identified categorized as follows: 7 alcohols, 11 aldehydes, 4 ketones, 4 organic acids, 7 esters, 2 ethers, 10 heterocycle compounds, 4 phenols, 2 terpenes and 2 polycyclic aromatic hydrocarbons. Eight adult beagle dogs were used for the preference test (two-pan test) and acceptance test (one-pan test) to rank these seven DFAs. PLSR was performed to correlate the instrumental data with the preference results. Twenty-three aroma compounds of hexanoic acid, acetaldehyde, heptanone, butyl hexanoate, heptyl formate, methyl pyrazine, 2,5-dimethyl pyrazine, 2-heptanone, pentanal, ethyl decanoate, heptanal, octanal, pentanol, acetone, ethyl caprylate, 3-methyl butanal, anisole, 2-ethyl hexanol, 2-pentyl furan, 2,3-butanediol, benzaldehyde, ethyl vanillin and vanillin correlated with the preference data. Benzaldehyde, vanillin and 2, 5-dimethyl pyrazine were added to dry dog foods in order to validate the PLSR results. The presence of three aroma compounds significantly increased the preferences of the samples (dry dog foods). The validation study involving the three compounds suggests that the 23 compounds selected by the PLSR model are aroma compounds which influence palatability. Therefore the manipulation of these flavor compounds could improve the palatability of dog foods.