Details

Autor(en) / Beteiligte

• Dreux, N
• Albagnac, C
• Carlin, F
• Morris, C.E
• Nguyen-The, C

Titel

Fate of Listeria spp. on parsley leaves grown in laboratory and field cultures

Ist Teil von

• Journal of applied microbiology, 2007-11, Vol.103 (5), p.1821-1827

Ort / Verlag

Oxford, UK: Oxford, UK : Blackwell Publishing Ltd

Erscheinungsjahr

2007

Quelle

MEDLINE

Beschreibungen/Notizen

• To investigate the population dynamics of Listeria monocytogenes and Listeria innocua on the aerial surfaces of parsley. Under 100% relative humidity (RH) in laboratory and regardless of the inoculum tested (10³-10⁸ CFU per leaf), counts of L. monocytogenes EGDe, LO28, LmP60 and L. innocua CIP 80-12 tended towards approx. 10⁵ CFU per leaf. Under low RH, Listeria spp. populations declined regardless to the inoculum size (10⁴-10⁸ CFU per leaf). L. innocua CIP 80-12 survived slightly better than L. monocytogenes in the laboratory and was used in field cultures. Under field cultures, counts of L. innocua decreased more rapidly than in the laboratory, representing a decrease of 9 log₁₀ in 2 days in field conditions compared to a decrease of 4·5 log₁₀ in 8 days in the laboratory. Counts of L. innocua on tunnel parsley cultures were always higher (at least by 100 times) than those on unprotected parsley culture. Even with a high inoculum and under protected conditions (i.e. plastic tunnels), population of L. monocytogenes on the surface of parsley on the field would decrease by several log₁₀ scales within 2 days. Direct contamination of aerial surfaces of parsley with L. monocytogenes (i.e. through contaminated irrigation water) will not lead to contaminated produce unless it occurs very shortly before harvest.