Department of Food Science, College of Agricuulture, University of Tabriz , peighambardoust@tabrizu.ac.ir
Abstract: (7902 Views)
Background and Objective: Flowability is one of the most important physical characteristics of powders, and under given circumstances, affects a large number of industrial applications. Environmental conditions during the processing or transport including temperature, humidity, electrostatic charge and time can critically affect the flowability of powders. The aim of this study was to investigate the spray drying parameters such as inlet air temperature, maltodextrin concentration and storage time on the physical and flowability characteristics of spray-dried malt extract.
Materials and Methods: In this study, a pilot-scale spray dryer was employed for drying the produced products. Process variables were inlet air temperature and maltodextrin concentration (DE=18-20). Maltodextrin as drying aid was used in 20, 30 and 40% (w/w) concentrations based on the wet weight of malt extract. Inlet air temperatures of 140, 160 and 180˚C in a co-current regime with feed were used. The effect of production conditions and particle size on the flowability indices (Hausner ratio, static angle of repose and compressibility index) during storage of the samples was investigated in a closed environment (RH= 44% using a saturated solution of magnesium nitrate) (p<0.05).
Results: Flowability of the powders was drastically reduced during the storage time due to the hygroscopicity. Furthermore, the results showed that by increasing the inlet air temperature and maltodextrin concentration, the particle size was increased, while stickiness and hygroscopicity significantly (p<0.05) were reduced leading to an increase in the powders’ flowability.
Conclusion: An inlet air temperature of 180˚C and a maltodextrin concentration of 40% had the most contribution on the physic-chemical characteristics and flowability of the powders during the storage time.
Keywords: Angle of repose Compressibility index Flowability Hausner ratio Malt extract powder Spray drying
Sarabandi K, Peighambardoust S H. Effect of Some Production Parameters and Storage Time on the Flowability Characteristics of Spray-dried Malt Extract Powder. Iranian J Nutr Sci Food Technol 2015; 10 (1) :51-60 URL: http://nsft.sbmu.ac.ir/article-1-1583-en.html