Application of Taguchi method to optimize garlic essential oil nanoemulsions

Essential oils have been recognised from both swine and poultry industries as an alternative to antimicrobial growth promoters as they pose a threat to animals and human health. Hence, the aim of this study was to develop garlic essential oil nanoemulsions (GEON) using Taguchi experimental design and emulsification method. Surfactant concentrations, mixing ratio, type of surfactant and stirring speed were selected as important factors influencing the droplet size and polydispersity index (PDI). The type of surfactant showed a greater effect on the droplet size and PDI during GEON preparation. The optimised nanoemulsion showed a droplet size, polydispersity index, good zeta potentials at 28.4 nm, 0.315 and 28.15 ± 1.1 mV, respectively. The compatibility of the garlic essential oil and Tween® 80 was ascertained by Fourier transform infrared spectroscopy. The presence of the important compounds of garlic in garlic essential oil nanoemulsions showed by gas chromatography-mass spectroscopy. Taguchi L-9 approach revealed to be an easy and useful tool to optimize various parameters investigated. Furthermore, the GEON was able to show antimicrobial activity improvement as an estimate to the garlic essential oil. The results of the study can be used further as a potential replacement for broiler growth performance in the near future.