Preparation and Testing of Food Freshness Indicators: an Application-Oriented Learning Module Integrating Basic Concepts of Microbiology and Chemistry Laboratory

We describe a novel 4-day food microbiology laboratory learning module for a first-year, introductory undergraduate course. In the module, the students test the suitability of four different pH indicator dyes as freshness indicators for dairy products. The concepts of serial dilutions, microbial growth, microbial metabolism, pH as well as pKa, and basic microbial laboratory practices are a part of the designed activity. It is a relatively inexpensive module and can be executed with little infrastructural support. It can be delivered as a stand-alone structured inquiry. The associated variables and applications indicate that the activity can perhaps be developed into a more elaborate course-based undergraduate research experience, or CURE.