Sorption Behavior, Glass Transition and Flowability of Powdered Orange Co-product

Abstract

The aim of this study was to contribute 100% to the circular economy models of the agri-food industry through the valorization of the whole orange juice co-product in order to offer it as a natural, versatile, high quality, and stable powdered food ingredient for human nutrition. Turning it into a cost-effective innovative product, with added value due to its high content of bioactive compounds, would lead to an increased competitiveness of the industrial sectors working with natural fibers. To ensure its efficient use for this purpose, co-product powder was characterized from a technological point of view in terms of the physicochemical aspects related to the presence of water and its ability to remain free-flowing and non-agglomerated, allowing for easy handling. The results of this study ensure the flowability of the freeze-dried orange co-product powder according to both the angle of repose (40°) and porosity (83%) values. However, it was also characterized as a hygroscopic product; therefore, specified conditions for a proper storage of the powdered co-product should be defined. In this case, both the refrigeration temperature and a relative humidity of under 35% should be established in order to avoid glass transition, thus remaining a free-flowing powder.