Combined Continuous Machine to Condition Olive Paste: Rheological Characterization of Olive Paste

Abstract

Food matrix structures are becoming more and more investigated from a rheological characterization point of view because this influences their behavior in the food process phases. In this study, a brief characterization of olive paste is attempted according to their rheological profile. Moreover, the influence of new technologies to prepare the olive paste on the rheological characteristics of olive paste is presented. The small olive oil droplet size, solid volume fraction, and the strong interactions of droplet interfaces are significant factors that change the rheological profile of the olive paste during the olive oil extraction process. The process involved, in fact, favors a decrease of viscosity of the initial matrix used which occurs mainly with the passage of the oil paste in the malaxer reaching an adequate viscosity. However, the viscosity of processed olive paste depends on the raw material, according to various factors such as the pedo-climatic conditions, agronomic techniques, the ripening index of the drupes, cultivars used, processing technologies that have a strong influence on the solid/liquid ratio. Therefore, the objective of the present study is to investigate the rheological properties of the olive paste when a combined heat-exchange and microwave machine are used.