Characterization of antioxidant and antimicrobial properties of spray-dried extracts from peanut skins

[Display omitted] •Peanut skin extracts were dried by spray-drying using maltodextrin as carrier.•Extract encapsulated at 170° with 30% maltodextrin had highest activity.•Powders were inhibitory to Staphylococcus aureus and Listeria monocytogenes.•Antioxidant activity of powders was stable for 120 days.•These powders have potential to be applied as natural additives to improve food quality. This study aimed to produce dried extracts from peanut skin using spray-drying technology for application as a natural antioxidant and antimicrobial in foods. The extracts were spray-dried with 10, 20, or 30% of maltodextrin (carrier) at different temperatures (130, 150, and 170°C), to establish the best conditions to produce the powders. The powders were characterized with regards to moisture, hygroscopicity, particle size, and solubility, and the stability of phenolic compounds was evaluated throughout 120days at 25°C. The antimicrobial and antioxidant activities of powders were also evaluated. Powders produced at higher temperatures and 30% of maltodextrin presented the best results for hygroscopicity, solubility, and particle size, and the powder produced at 150°C with 30% of maltodextrin showed the high stability of phenolic compounds during storage. All powders presented remarkable antioxidant activity and showed bacteriostatic activity against Listeria monocytogenes, and bactericidal activity against Staphylococcus aureus. Taken together, these results indicate that the best conditions (of those tested) for spray drying peanut skin extracts were at 150°C and with 30% of maltodextrin. The resultant powders have technological potential due to the high stability, good physical properties, and remarkable antioxidant/antimicrobial activities, which could be applied as natural additives to improve food quality.