Quantification of Leuconostoc populations in mixed dairy starter cultures using fluorescence in situ hybridization

Development of a rapid method to identify and quantify Leuconostoc populations in mesophilic starter cultures.

16S rRNA-targeted oligonucleotide probes were used in a whole cell in situ hybridization assay for the identification of the genus Leuconostoc and an undescribed Leuconostoc ribospecies. The probes were fluorescently labelled and used to quantify the Leuconostoc populations in five different mixed starter cultures.

There was a good correlation between the results obtained using fluorescence in situ hybridization (FISH) with that of standard plate counting methods.

To develop a FISH method capable of identifying and quantifying the Leuconostoc population in starter cultures within 1 day.