Recent developments in the spray drying of sugar-rich products such as fruit juices, pulp and honey with and without the application of carriers, e.g., carbohydrate carriers (maltodextrin, gum arabic), prebiotic dietary fibers, proteins and natural carriers have been presented in this paper. The effect of the carrier type, carrier concentration and the spray drying process parameters on the product yield and selected final product properties are analyzed and discussed. Recent studies have proved that prebiotic dietary fibers and proteins may substitute conventional carriers, i.e., refined carbohydrates, providing high product yield and additional nutritional value at lower carrier concentration in the final product.

A unique experimental equipment for extensive trials on the spray drying kinetics and particles residence time involving “in situ” analysis of the properties of continuous and dispersed phases was designed, built, and tested. Advanced experimental techniques (including laser techniques) to determine current parameters of spray drying process (temperature, humidity, moisture content) and current structure of spray (particle size distribution, particle velocities, etc.) were employed. Full scale spray drying tests of baker's yeast and maltodextrin enabled identification of the effect of process parameters on drying kinetics and spray residence time in the tower. Quantitative relationship describing spray drying kinetics as a function of atomization ratio and drying agent temperature were determined. The experimental results proved that spray residence time was controlled by atomization ratio and airflow rate. Drying kinetics in spray drying process is presented for the first time in the literature.