Rheological behavior of o/w emulsions formulated with orange seed proteins treated by high-intensity ultrasound

Abstract

There is a current demand for new sources of plant-based proteins with the aim of promoting sustainability associated with healthy nutritional habits. In addition to the nutritional issues, these macromolecules have an important technological role in the formulation of foods such as emulsions, specifically. The byproducts of the orange juice processing industry are abundant in northwest São Paulo and, due to their composition, they are renewable sources of compounds of interest. Orange seeds, in particular, have a noticeable protein content with emulsifying potential. In order to enhance the obtaining functional properties, its modification through high-intensity ultrasound (US) treatment has been highlighted as a clean and efficient technology. On the other hand, few researches have been reported on the effect of these modified proteins on the rheological behavior of emulsions. In this sense, the general objective of this proposal will be to evaluate the efficiency of protein extraction from orange seeds and the effect of ultrasound treatment on the rheological behavior of resulting o/w emulsions. The dried and defatted seeds will be chemically characterized and subsequently extracted in an alkaline medium followed by isoelectric precipitation. The protein fraction will be treated with ultrasound at different intensity levels. As responses, the extraction yield and the water and oil retention capacity of the protein extract will be firstly evaluated. Oil in water emulsions will be prepared and their rheological behavior will be determined through stationary and oscillatory tests. Mathematical modeling will be used to characterize and compare the results.