Roasted coffee oil microencapsulation by spray drying and complex coacervation techniques: Characteristics of the particles and sensory effect

Abstract

The objective of this research was to microencapsulate roasted coffee oil using spray drying (SD) and complex coacervation (CC) techniques and to compare the microparticles properties and their sensory impact on the perception of soluble coffee brew aroma. Starch was used as wall material for spray dried microparticles (MSD), and gelatin and gum Arabic for that produced by complex coacervation (MCC). Ultrasound stable emulsions were obtained. Both microparticles presented a continuous wall and similar glass transition temperature (49.3 °C). MSD had 10.2% oil content and low surface oil content, and high solubility and wettability. MCC stood out for its high oil content (42.8%) and larger diameter (125 μm). Sensory evaluation showed that, when dissolved in hot water, microparticles provided a coffee aroma. Despite the MCC brew was preferred by assessors, the perception of coffee aroma intensity during the preparation of a soluble coffee brew containing MSD or MCC were similar.