Molecular characterisation of bacterial contamination in semi-final gelatine extracts, using denaturing gradient gel electrophoresis.

Contamination of gelatine may affect the safety and/or quality of its applications. Characterisation of bacterial isolates from semi-final gelatine batches revealed thermotolerant, aerobic, endosporeforming contaminants. In this paper, bacterial contamination in gelatine batches is analysed without previous isolation, by means of denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rDNA sequences. V9 and V6-V8 regions of the 16S rDNA gene were found more suitable for this purpose than V1 or V3 regions. Bacillus fumarioli, Bacillus licheniformis, members of the 'Bacillus cereus group', Bacillus subtilis, Bacillus shackletonii, Brevibacillus borstelensis and Brevibacillus agri were detected.