Drying of aqueous lactose solutions in a single stream dryer

Spray-dried lactose is a useful ingredient in many food and drug preparations. In the literature, many articles have attempted to mathematically characterize the drying kinetics and the product quality during spray drying of various dairy products using a number of approaches. As far as lactose is concerned, little mathematical analysis is available regarding its detailed drying kinetics. Recently, the reaction engineering approach (REA) was found to be useful to formulate a drying kinetics model for drying of aqueous lactose droplets. The main objective of this work is to determine the sensitivity of the REA in order to assess its performance over different drying and feed conditions, which may be relevant to an industrial scenario. A single stream drying ((SD)-D-2) approach was used for modeling the air-drying of aqueous lactose droplets, as this technique is simple to be used and reduces the computation time. Some laboratory results on the physical characteristics of the air-dried lactose particles are also reported using the (SD)-D-2 approach. (C) 2007 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.