 Samples collected during the incubation will be analysed by centrifuging the sample to create a pellet containing bacteria and a supernatant containing a wide range of metabolites. The bacteria will be analysed by extracting their DNA for genomic analysis or using RNA based approaches. On occasion, conventional microbiological techniques might be used. The supernatant will be filter sterilised prior to analysis of its chemical composition by techniques such as mass spectrometry, gel electrophoresis, or chromatography. Alternatively the supernatant may be added to cell lines to model the interaction between the bacterial ecosystem and the cells lining the colon. 