In the present study, models to predict the simultaneous growth of
L. monocytogenes and mesophilic LAB in two different types of cottage
cheese were developed and successfully validated. The mesophilic LAB
cultures had an important inhibiting effect on themaximumpopulation
density (Nmax) of L. monocytogenes and the new models were able to
predict this microbial interaction for storage conditions and product
characteristic of relevance for cottage cheese (Table 5, Fig. 5). The
models' range of applicability, as determined from product validation
studies, included cottage cheese with both fresh- and cultured cream
dressing, pH from 5.0 to 5.5, initial concentrations of lactic acid below
2500 ppm and of sorbic acid below 1000 ppm, water phase salt of
1.0–1.25% and storage temperatures from 5 °C to 15 °C. The new
models can be used to conveniently evaluate the growth potential of
L. monocytogenes in cottage cheese depending on product characteristics
and storage conditions.