These bacteriocins, isolated from fermented foods such as ‘burong kanin’ and ‘balao-balao,’ are antimicrobial to Listeria monocytogenes but not to Lactobacillus casei and other beneficial lactic acid bacteria. They have been purified and characterized as similar to pediocin by polymerase chain reaction. The pure proteinaceous form of the bacteriocins, containing common amino acids, makes them safe in the gut, as they will be digested like an ordinary protein. The bacteriocins’ heat tolerance (up to 121 ºC) and tolerance to acidic and neutral pH makes them ideal for food processing applications. Because it inhibits the growth of psychrophilic food pathogens such Listeria monocytogens, the bacteriocins can be used as antimicrobial additives for various food products being stored at refrigerated conditions.