Growth modelling of Listeria monocytogenes in packaged fresh green asparagus

Growth of Listeria monocytogenes in packaged fresh green asparagus was inve stigated at different temperatures The present study monitored the growth o f L. monocytogenes in packaged fresh green asparagus stored at 2, 4, 8, 12 and 20 degrees C. Changes in carbon dioxide, oxygen concentrations and pH w ere determined. Growth data were fitted to the Baranyi equation The influen ce of storage temperature was very apparent, at higher temperatures (8, 12 and 20 degrees C) an increase of two logarithmic units of L. monocytogenes took place, criteria used for the determination of the sanitary risk. The r ecommended storage temperatures for the optimal and safe conservation of as paragus are the lower ones studied (2 and 4 degrees C), because growth of L . monocytogenes is not allowed, although it can survive, so in cases of a h igh contamination of this micro-organism it could be a sanitary risk. Predi ctive modelling appears to be a useful tool in estimating growth rates of L . monocytogenes in these products. (C) 2000 Academic Press.