Description of a simple detection assay for in situ production of bacteriocin on meat

Using a modification of the agar diffusion assay, in situ bacteriocin production on meat was analyzed using cooked meat medium (CMM) and sterile pork tissue (lean and fat) with Carnobacterium piscicola LV17 as the producer and Carnobacterium divergens LV13 as the indicator strains. Contrary to what is observed in APT broth, bacteriocin production by C. piscicola LV17 occurred with growth at low inoculum levels (< or =10(4) CFU/cm2 or g of meat) on disks (10 cm2) of pork fat tissue (pH 6.58) and on CMM particles (pH 7.0) but not on disks of lean tissue (pH 5.61). The assays described in this study do not required sophisticated equipment and would be useful to study bacteriocin production on meat products stored under various conditions.