The Antimicrobial and Organoleptic Effects of Mentha aquatica Essential Oil on Kluyveromyces marxianus in Iranian Yoghurt Drink

Mentha aquatica is one of the species of mint family. The essential oil of this plant has shown effective antimicrobial properties on various kinds of microorganisms in the culture. This study aims to investigate the preventive influence of Mentha aquatic essential oil on viability of Kluyveromyces marxianus in Iranian yoghurt drink.
Mentha aquatic essential oil was obtained by distillation method employing Clevenger apparatus. The effective composition of the essential oil was identified by Gas Chromatography equipped with Mass Spectrometer (GC/MS). The inhibitory effect of Mentha aquatic essential oil on kluyveromyces marxianus was examined on Muller Hinton agar culture using diffusion disk method. After assurance of its antimicrobial properties, the Inhibitory influence of Mentha aquatic essential oil was studied on Kluyveromyces marxianus at 0.05, 0.1, 0.125 and 0.25% concentrations in Iranian drinking yoghurt during 28 days of storage.
The results showed that Mentha aquatica essential oil has the highest inhibitory effect on Kluyveromyces marxianus growth at high concentrations. Concerning the antimicrobial property and organoleptic characteristics, it might be concluded that 0.1% concentration of the essential oil might be regarded as the optimum concentration.
It can be concluded that Mentha aquatic essential oil, caused a declining effect on the viability of microorganism studied.