A molecular method to detect Bacillus cereus from a coffee concentrate sample used in industrial preparations.

ABSTRACT

AIMS: The aim of this work was to develop specific primers which are able to detect Bacillus cereus in a coffee concentrate sample. METHODS AND RESULTS: A pre-PCR step to clean the DNA, used for PCR, was developed to avoid PCR inhibition by Maillard products. The combination of centrifugation and washing the pellet, employing EDTA and water, before DNA extraction improved the detection of low numbers of B. cereus cells (10 cells ml-1). The development of specific primers enabled to detect low numbers of B. cereus without the need of a pre-enrichment step. CONCLUSIONS: The data obtained demonstrated the specificity and the sensitivity of the primers that could be used to check the presence of B. cereus in different food products, avoiding the need for labourious and time-consuming culture-based techniques. SIGNIFICANCE AND IMPACT OF THE STUDY The method could help food microbiologists to check food samples quickly for the presence of B. cereus.