Influences of physicochemical stresses on injury and inactivation behaviour of Listeria innocua

Fátima A. Miller Orcid logo ,
Fátima A. Miller
Bárbara Ramos ,
Bárbara Ramos
Maria M. Gil ,
Maria M. Gil
Teresa R.S. Brandão ,
Teresa R.S. Brandão
Paula Teixeira ,
Paula Teixeira
Cristina L.M. Silva
Cristina L.M. Silva

Published: 01.12.2016.

Volume 6, Issue 2 (2017)

https://doi.org/10.7455/ijfs.v6i2.363

Abstract

Many minimally processed foods depend on a combination of inhibitory factors to reduce the hazard of foodborne illness. Therefore, inactivation of Listeria innocua was studied according to a 24 factorial experiment designed to draw conclusions about temperature (52.5 °C and 65.0 °C), pH (4.5 and 7.5), water activity (aw=0.95 and 0.99) and solute type (NaCl and glycerol) effects. Three different recovery media were used to assess injured cells. Survival data were fitted with a Gompertz-based model and kinetic parameters (shoulder, maximum inactivation rate – kmax, and tail) were estimated. Results showed that shoulder was affected by temperature, pH and combined effects; kmax was influenced by all factors and their combinations; and tail was affected by aw, temperature and aw/pH combination. Results demonstrated the potential occurrence of microbial cross-protection survival techniques between the various stresses, e.g. heat and osmolarity. Indeed, this work clearly established that, to avoid hazards, Listeria inactivation must be evaluated with a maximum of environmental factors that undergo alterations. Only thus, appropriate food preservation treatments can be developed and consequently, the safety of food products can be assured.

Citation

Copyright

Article metrics

Google scholar: See link

The statements, opinions and data contained in the journal are solely those of the individual authors and contributors and not of the publisher and the editor(s). We stay neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Most read articles

Indexed by