INABILITY OF HEAT-STRESS TO AFFECT SENSITIVITY OF LISTERIA-MONOCYTOGENES TO PEDIOCIN IN PORK

Citation
A. Khojasteh et Ea. Murano, INABILITY OF HEAT-STRESS TO AFFECT SENSITIVITY OF LISTERIA-MONOCYTOGENES TO PEDIOCIN IN PORK, Journal of food safety, 16(3), 1996, pp. 201-208
Citations number
14
Categorie Soggetti
Food Science & Tenology","Biothechnology & Applied Migrobiology
Journal title
ISSN journal
01496085
Volume
16
Issue
3
Year of publication
1996
Pages
201 - 208
Database
ISI
SICI code
0149-6085(1996)16:3<201:IOHTAS>2.0.ZU;2-X
Abstract
The effect of heat-shock (48C for 20 min) on sensitivity of Listeria m onocytogenes Scott A to bacteriocin produced by Pediococcus acidilacti ci was evaluated. Exposure of Listeria to pediocin (68, 267AU/mL) resu lted in lower number of survivors in the first 2 h of incubation in Tr ypticase soy broth at 37C compared with samples without pediocin, rega rdless of whether the cells were heat-shocked or not. Further incubati on for 24 h resulted in resumption of growth by L. monocytogenes, with counts reaching the same level as samples without pediocin. Cold stor age of Listeria in pork in the presence of pediocin (8, 192 AU/g) resu lted in a 2.0 log(10) reduction after 24 h, when compared with control s not exposed to pediocin, regardless of whether the samples were stor ed under air, vacuum, or a modified atmosphere. Prior heat-shocking di d not have an effect on sensitivity of Listeria to pediocin during sto rage. Thus, storage atmosphere and exposure to heat shock, which are k nown to induce thermotolerance in L. monocytogenes, had no effect in s ensitivity of this organism to pediocin.