Mathematical modeling and simulation of refractance window drying of whole milk and yoghurt

Abstract

Dairy products as milk and yoghurt are widely consumed in the world due to their high nutritional content and health benefits. However, these products can be deteriorated over time and require high operational costs due to their moisture content. Drying is a technology that reduces the moisture content, preserves the quality, and increases the shelf life of the foods without greatly affecting the nutritional properties. Refractance window (RW) drying is a novel method that allows the development of new foods with high quality and nutritional value and has advantages over other techniques, using shorter operation times, lower consumption energy, and lower operational costs. On the other hand, mathematical models allow the study of different processes in the industry and minimize problems such as excessive energy consumption and equipment wear. To date, research has been carried out focused on the study of the properties of products drying main by Spray and Convective drying. However, there are few studies related to the RW drying and the study of effects on dairy powders. Besides, there is no evidence of the development of models for the drying of whole milk and semi skimmed yoghurt. In this work, a two-dimensional mathematical model for coupled heat and mass transfer during RW drying of whole milk and semi skimmed yoghurt was implemented. Also, the present study aimed to determine the effect of RW drying on the physicochemical properties as reconstitution properties, denaturation protein, and color of whole milk and yoghurt.