(185g) Spry Drying System Modelation for Orange (Citrus sinensis) Juice Drying Using Open Foam

Drying is a method for food preservation that consists in extracting the water to decrease the water activity and delay degradation reactions. Conventional drying processes involve high temperatures and long residence time, this can decrease the quality of the food in terms of its appearance and organoleptic properties, also, it can lose much of its nutritional value. Spray drying is a method that uses moderate pressure and temperature conditions. It is used to dry thermally sensitive foods, with a solids content lower than 50%. The product obtained is a powder material with a low moisture content and a uniform particle size.

There are 6 variables that control the spray drying phenomenon of mass and heat transfer: 1) air and feedstock flow ratio 2) temperature of the air stream 3) temperature of the feedstock stream 4) atomizer speed 5) type of carryer agent and 6) concentration of the carryer agent. This amount of variables complicate the search of an optimal point of operation, doing the experimental work arduous and expensive. For this reason, the popularity of computational tools like computational fluid dynamics (CFD) has grown in past years, as this tool allows system behavior evaluation for diverse operating conditions with low investment in resources

In this work the drying of a Colombian native orange variety (Citrus sinensis) is evaluated using spray drying at laboratory scale. The operational variables of the process were obtained and validated through computer models for the design of an industrial scale spray drying process, in order to obtain a powder that conserves more than 90% of the nutrients and good organoleptic properties that allow new market opportunities (mainly exportations) to the farmers who grow the fruit.