44 research outputs found
Growth of Listeria monocytogenes as influenced by viscosity and water activity
The effects of osmotic stress on Listeria monocytogenes growth parameters was examined in relation to the viscosity of the
growth media. In low-viscosity systems, growth of L. monocytogenes in glucose-supplemented media was comparable to
growth in sucrose-supplemented media. The relative lag time (RLT: the lag time divided by the generation time) responses were
found to increase in the more restrictive water activity conditions. In high-viscosity systems containing polyvinylpyrrolidone
(PVP), growth rate was reduced, whereas lag time showed no discernible modification. Osmotic stress in medium- and highviscosity
media supplemented with glucose resulted in approximately exponential increasing of the RLT values. Thus, the
biological effects of osmotic stress on L. monocytogenes could be affected by the physical properties of the system, such as
viscosity and diffusivity