Physical properties, morphology and saltiness of salt particles as affected by spray drying conditions and potassium chloride substitution

Abstract

Since excessive intake of sodium increases the risk of an array of diseases, much effort has been made to reduce sodium in food. Here, combined use of spray drying and KCl substitution to modify the physical properties and morphology of KCl/NaCl salt particles was attempted. The effects of inlet air temperature, feed flow rate and KCl substitution level on the moisture content, particle size, surface area, bulk density, hygroscopicity, crystallinity, morphology, N2-sorption characteristics, crystallinity and saltiness of the salt particles were determined. Combined use of KCl and NaCl created surface irregularities and pore interiors of the salt particles. Although higher feed flow rate and KCl substitution level resulted in significantly larger particle size, salt particles with the highest KCl substitution level (30%) exhibited highest hygroscopicity and saltiness because of their lower bulk density and existence of agglomeration, surface roughness and macro pores. All spray-dried salt particles were noted to be crystal-like.