Effect of spray drying on physicochemical characteristics and quality of peppermint powder

Peppermint is a very aromatic herbal plant with mouth cooling effect, having pungent mint and menthol flavor. It has many phenolic compounds (flavonoids, tannins, anthocyanin) which are considered as natural antioxidants. The aim of this study was to investigate the influence of different concentrations of maltodextrin and inlet air temperature on some properties of encapsulated peppermint extract. Spray drying is the most common and economical method of microencapsulation. In the current project, the impact of three different inlet air temperatures (140, 160 and 180 °C) and maltodextrin (DE=20-18) concentrations (10, 20 and 30%) on production efficiency, moisture content, water activity, solubility, hygroscopicity, wettability and color parameters of spray dried peppermint extract powder were investigated. The results showed that increasing inlet air temperature and maltodextrin concentration led to increase in the production yield, powder solubility, L* and Hue parameters. While moisture content, water activity, hygroscopicity, wettability, chroma, a* and b* parameters were decreased. In conclusion, inlet temperature of 160 °C and maltodextrin concentration of 20% considered as optimum conditions maintaining desirable properties of peppermint extract powder during spray drying process