Eucalyptus globulusEssential Oil as a Natural Food Preservative: Antioxidant, Antibacterial and Antifungal PropertiesIn Vitroand in a Real Food Matrix (Orangina Fruit Juice)

The potential application ofEucalyptus globulusessential oil (EGEO) as a natural beverage preservative is described in this research. The chemical composition of EGEO was determined using gas chromatography analyses and revealed that the major constituent is 1,8-cineole (94.03% +/- 0.23%). Thein vitroantioxidant property of EGEO was assessed using different tests. Percentage inhibitions of EGEO were dose-dependent. In addition, EGEO had a better metal ion chelating effect with an IC(50)value of 8.43 +/- 0.03 mg/mL, compared to ascorbic acid (140.99 +/- 3.13 mg/mL). Thein vitroantimicrobial effect of EGEO was assessed against 17 food spoilage microorganisms. The diameter of the inhibitory zone (DIZ) ranged from 15 to 85 mm for Gram-positive bacteria and from 10 to 49 mm for yeast strains.Candida albicans,C.parapsilosisandSaccharomyces cerevisiaewere the most sensitive fungal species to the EGEO vapor with DIZ varying from 59 to 85 mm. The anti-yeast effectiveness of EGEO alone and in association with heat processing was estimated in a real juice matrix (Orangina fruit juices) in a time-dependent manner. The combination of EGEO-heat treatment (70 degrees C for 2 min) at different concentrations (0.8 to 4 mu L/mL) was effective at reducingS. cerevisiaegrowth in the fruit juice of Orangina, compared to juice preserved with synthetic preservatives. Current findings suggest EGEO as an effective and potent inhibitor of food spoilage fungi in a real Orangina juice, and might be a potential natural source of preservative for the food industry.