AIM: Use of a bacteriocin-producing lactococcal strain to control Listeria monocytogenes in jben. METHODS AND RESULTS: A Lactococcus lactis strain isolated from lben was shown, by the spot technique, to produce a bacteriocin different from nisin. Inhibitory activity of the bacteriocin-producing strain against Listeria monocytogenes was investigated in jben, made from cow's milk fermented with the producer organism and contaminated with 104 or 107 cfu ml-1. Listeria counts were monitored during manufacture, and during conservation at room and at refrigeration temperatures. Results showed that the pathogen was reduced by 2.7 logarithmic units after 30 h of jben processing when the initial inoculum of 107 cfu ml(-1) was used. For the initial inoculum of 104 cfu ml(-1), the bacterium was completely eliminated at 24 h. Furthermore, the use of the bacteriocin-producing starter culture extended the shelf-life of jben by 5 days. CONCLUSIONS: In situ production of the lactococcal bacteriocin is an efficient biological means of controlling L. monocytogenes in jben and of allowing shelf-life extension. SIGNIFICANCE AND IMPACT OF THE STUDY: The proposed technology will essentially benefit minimally processed dairy products and those made with raw milk.
AIM: Use of a bacteriocin-producing lactococcal strain to control Listeria monocytogenes in jben. METHODS AND RESULTS: A Lactococcus lactis strain isolated from lben was shown, by the spot technique, to produce a bacteriocin different from nisin. Inhibitory activity of the bacteriocin-producing strain against Listeria monocytogenes was investigated in jben, made from cow's milk fermented with the producer organism and contaminated with 104 or 107 cfu ml-1. Listeria counts were monitored during manufacture, and during conservation at room and at refrigeration temperatures. Results showed that the pathogen was reduced by 2.7 logarithmic units after 30 h of jben processing when the initial inoculum of 107 cfu ml(-1) was used. For the initial inoculum of 104 cfu ml(-1), the bacterium was completely eliminated at 24 h. Furthermore, the use of the bacteriocin-producing starter culture extended the shelf-life of jben by 5 days. CONCLUSIONS: In situ production of the lactococcal bacteriocin is an efficient biological means of controlling L. monocytogenes in jben and of allowing shelf-life extension. SIGNIFICANCE AND IMPACT OF THE STUDY: The proposed technology will essentially benefit minimally processed dairy products and those made with raw milk.
Authors: Elena R Ramos; Ricardo A Santos; Encarna Velázquez; Carmen E Velezmoro; Doris E Zúñiga Journal: World J Microbiol Biotechnol Date: 2018-09-10 Impact factor: 3.312
Authors: Sofia Cosentino; Maria Elisabetta Fadda; Maura Deplano; Roberta Melis; Rita Pomata; Maria Barbara Pisano Journal: J Biomed Biotechnol Date: 2012-03-27
Authors: Danielle N Furtado; Svetoslav D Todorov; Mariza Landgraf; Maria T Destro; Bernadette D G M Franco Journal: Braz J Microbiol Date: 2015-03-01 Impact factor: 2.476