Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) fingerprinting was recently introduced into food microbiology. This paper describes the technique and reports on the state-of-the-art application of this technique to food and food-related ecosystems. Applications of PCR-DGGE in several fields of food microbiology are reviewed: the identification of microorganisms isolated from food, the evaluation of microbial diversity during food fermentation, and microbiological and commercial food quality assessment. Potentials and limitations of this culture-independent approach in food microbiology are indicated and future perspectives are discussed.