Modeling the Inactivation of Listeria innocua and Escherichia coli in fresh-cut tomato treated with pulsed light

The effectiveness of pulsed light (PL) treatments to inhibit microorganisms on fresh-cut tomatoes (Lycopersicon esculentum Mill., cv. Daniela) was investigated. Tomato slices inoculated with Escherichia coli or Listeria innocua were exposed to PL treatments (4, 6, or 8 J cm−2 fluence) and kept cold...

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Detalles Bibliográficos
Autores: Valdivia Nájar, Carlos Guillermo, Martín Belloso, Olga, Giner, Joaquim, Soliva-Fortuny, Robert
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2017
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10459.1/59453
Acceso en línea:https://doi.org/10.1007/s11947-016-1806-y
http://hdl.handle.net/10459.1/59453
Access Level:acceso abierto
Palabra clave:Fresh-cut tomato
Pulsed light treatments
Listeria innocua
Escherichia coli
Descripción
Sumario:The effectiveness of pulsed light (PL) treatments to inhibit microorganisms on fresh-cut tomatoes (Lycopersicon esculentum Mill., cv. Daniela) was investigated. Tomato slices inoculated with Escherichia coli or Listeria innocua were exposed to PL treatments (4, 6, or 8 J cm−2 fluence) and kept cold at 4 °C for 20 days. L. innocua and E. coli counts, gases in the headspace of the containers (O2 and CO2), pH, titratable acidity, and soluble solid content were monitored throughout the cold storage. The PL treatments reduced significantly (p < 0.05) initial loads of both microbes. The effect of the PL fluence on the survival number of microoganisms was described by a log-linear model (R2 = 0.849–0.999). At any fixed time within the cold storing, the microbial counts for untreated samples were always higher than those cut tomatoes that had been previously PL-treated. The behavior of L. innocua and E. coli during the storage were well adjusted (R2 > 0.930) by Gompertzian models; the studied microorganisms exhibited different patterns during the storage period. On the other hand, O2 and CO2 partial pressures in containers with fresh-cut tomatoes were also significantly affected by PL treatments (p < 0.05). The highest PL fluence caused the greatest changes of O2 and CO2 contents. In addition, the application of PL triggered an acceleration of the O2 consumption during the cold stage. PL treatments might be used to effectively extend the safety of fresh-cut tomatoes over 12 days of storage against E. coli and L. innocua growth.