The aim of this work was to study the influence of emulsion characteristics on exergy efficiency and quality of fish oil microencapsulated within skim milk powder (SMP) by spray drying. Response surface method (RSM) and genetic algorithm (GA) were applied to optimize the emulsion preparation procedure for production of fish oil microcapsule. The proposed emulsions were prepared, according to a central composite design and the feeds were dried using a mini spray dryer. Independent variables were: aqueous phase content. oil proportion in total solids, and emulsification time. The encapsulation efficiency and exergy efficiency were considered as dependent variables. The RSM was used to build the mathematical equations and created models were integrated by applying three approaches to determine the fitness value of GA. Finally, the optimal emulsion preparation procedure was determined to simultaneously obtain the highest values for both encapsulation efficiency and exergy efficiency. The results of authentication test for selected emulsion procedure preparation demonstrated the ability of applied approach for designation of sustainable and qualified process in fish oil microencapsulation by spray drying. (C) 2012 Elsevier B.V. All rights reserved.