Impact of pulsed electric fields on fermentation process during yogurt production

Abstract

A study on the effect of pulsed electric fields (PEF) application to the inoculum for natural drinkable yogurt production is presented in this dissertation. This research involves the fermentation time optimization of yogurt production through the application of PEF, as well as the evaluation of the proximal composition, physicochemical characterization, and a discriminatory sensory perception test immediately after processing and during storage of the obtained yogurt treated with PEF, having a control yogurt as a reference. Chapter 1 includes the motivation, problem statement, and context of this study. Chapter 2 is related to the hypothesis and objectives. Chapter 3 comprises the theoretical framework regarding yogurt production, Lacto-fermentation, and PEF principles and applications. Chapter 4 details the materials and methods to conduct the experimental work. Chapter 5 focuses on the results analysis and a discussion. Chapter 6 includes conclusions and recommendations. Finally, it is included a disclosure regarding scientific material and an appendix section containing complementary information collected during data organization and analysis. Overall, this master’s dissertation demonstrated that PEF technology is a potential alternative to optimize yogurt production processes through the reduction of fermentation time without significantly altering its proximal content and physicochemical characteristics and sensory perception, resulting in a final pro are included duct similar to that one obtained by the conventional process.