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Several essential oils (EO) are efficient inhibitors of foodborne pathogen growth. However, their direct incorporation into food presents technological challenges, because of the possibility of extreme changes to their sensory properties. Such drawbacks can be overcome by encapsulation techniques, such as nanoemulsification. This study produced nanoemulsions encapsulating different amounts of oregano (Origanum vulgare) EO, using the phase inversion temperature method, and their physicochemical stability and antibacterial activity were evaluated. The average droplet diameters of the nanoemulsions were in the range of 35–55 nm, and nanoemulsions containing 5 g EO/100 g nanoemulsion were the most stable over the storage period of 45 days. The nanoemulsions exhibited good antibacterial action demonstrated by the low values in vitro for minimum inhibitory concentration (0.56 and 0.60 mg oregano EO/mL for Staphylococcus aureus and Escherichia coli, respectively, and for minimum bactericidal concentration, 0.90 and 3.32 mg oregano EO/mL for Staphylococcus aureus and Escherichia coli, respectively). The nanodispersions also had a higher antibacterial effect against E. coli than for S. aureus. The incorporation of nanoemulsions in chicken pâte did not change the physicochemical characteristics of the meat product. Therefore, the results obtained indicated that nanoemulsions encapsulating oregano EO are suitable to be incorporated into food formulations, such as chicken pâte, to prevent and control microbial growth and to extend their shelf life.

Quercetin is a flavonoid with high antioxidant capacity that provides beneficial biological effects. However, the absorption rate of quercetin in the gastrointestinal tract is low but encapsulated lipid matrices, such as liposomes, can be useful to enhance its bioavailability. In this study, quercetin-loaded liposome dispersions were produced by ethanol injection and 12 mM of phospholipid encapsulating 0.3% molar quercetin was suitable to evaluate physicochemical stability. The Langmuir monolayer technique indicated that it was possible to encapsulate a maximum of 0.3% molar quercetin in liposomes. Quercetin-loaded liposome dispersions presented a mean hydrodynamic diameter of 264 nm and a zeta potential of −17 mV, which is typical for small unilamellar vesicles produced by ethanol injection. Sucrose was used as the lyoprotectant (mass sucrose: phospholipid ratio, 4:1), and the encapsulated quercetin had not degraded after 100 days of storage. In addition, the lyophilized liposomes presented a low propensity for water adsorption and low hygroscopicity. Such behavior is considered highly suitable for stability in dried foods.