Predictive model for the behavior of Listeria monocytogenes Scott A in Shrikhand, prepared with a biopreservative, pediocin K7 Original Research Article

The limited facilities of hygiene and sanitation during production of traditional dairy foods combined with lack of refrigerated storage throughout the cold chain pose a serious challenge to their microbial safety. The application of biopreservatives like pediocin is promising in controlling the growth of L. monocytogenes in food systems. In the present study, polynomial equations were derived using multivariate analysis, for predicting the survival of L. monocytogenes Scott A, in Shrikhand, a traditional sweetened lactic-fermented milk product with varying parameters of initial Listeria inoculum (3·3, 4·3, 5·3, 6·3 & 7·3 log10cfu g−1), storage temperature (4, 10, 16, 22 & 28°C), storage period (24–120 h) and pediocin K7 levels (11, 14, 17, 20 & 23%). The model predictions indicated the effectiveness of higher pediocin levels, higher storage temperatures and extended periods of storage in inhibiting the growth of L. monocytogenes Scott A in Shrikhand. Further, the comparison of experimental and predicted values of the survival of L. monocytogenes Scott A in Shrikhand, using bias factor, established the adequacy of the derived model to describe the behavioral pattern of L. monocytogenes Scott A in Shrikhand.