Experiential Learning of Lactic Fermentation Through Yogurt Production Using the Semi-Direct Method

Abstract

This study addresses the teaching of lactic acid fermentation through an experiential approach based on yogurt production, aiming to enhance the understanding of biochemical processes and their application in the food industry. To achieve this, a laboratory experience was conducted with 45 students from the Faculties of Health Sciences and Engineering Sciences at the Universidad Tecnológica Empresarial de Guayaquil, who produced natural and strawberry-flavored yogurt. Physicochemical parameters such as pH and titratable acidity were analyzed, and a sensory evaluation was performed using a tasting panel. Additionally, a validated questionnaire was applied to measure students' perception of their learning experience. The results showed a reduction in pH to values of 4.8 and 4.7 for natural and strawberry yogurt, respectively, within the expected commercial range, as well as an increase in titratable acidity, indicating effective fermentation. The sensory analysis revealed high product acceptance, highlighting its creamy texture and balanced acid-sweet flavor. More than 80% of students recognized the influence of variables such as temperature and incubation time on yogurt quality, reinforcing their understanding of the fermentation process. In conclusion, experimentation-based teaching strengthened students' practical learning, facilitating knowledge acquisition and increasing their interest in biotechnology applied to the food industry.