Kimchi: Spicy Science for the Undergraduate Microbiology Laboratory

Abstract

Undergraduate microbiology courses offer a perfect opportunity to introduce students to historical food preservation processes that are still in use today. The fermentation of vegetables, as occurs in the preparation of sauerkraut and kimchi, uses an enrichment step to select for the growth of naturally occurring lactic acid bacteria (LAB). This is an active learning exercise in which students learn a food preparation skill and basic microbiological terms such as selection and enrichment. When performed in conjunction with cultured fermentations, such as yogurt making, students can see the difference between fermentations by naturally occurring microorganisms versus inoculated microorganisms. Additionally, this exercise introduces students to concepts of food safety, intrinsic factors influencing microbial growth such as pH, and cultural uses of fermentation to preserve locally available foods.