Abstract

In this research, spray drying was used to produce malt extract powder. The effect of two parameters including inlet air temperature (at levels 160, 170, 180°C) and maltodextrin concentration (at levels 0, 10, 20, 30%) was investigated on malt extract powder properties including particle size, theoretical specific surface area, particle size distribution and span value, scorched particles and solubility index, vitamin B₂ content, glass transition and sticky point temperature. Results indicated that spray drying method produced a malt extract powder with high quality. The drying efficiency depended on inlet air temperature and maltodextrin concentration. Increasing inlet air temperature and maltodextrin concentration enhanced the drying performance. The highest quality factors for the powdered malt extract were obtained at 170°C and 20% maltodextrin, which included disk B for scorched particles, solubility amount=0.05 ml, average particle size= 22 microns, vitamin B₂ content=1.56mg/100g.

Keywords: Inlet air temperature, Maltodextrin, Malt extract, Spray drying, Vitamin B₂.