Modelling Bacillus cereus adhesion on stainless steel surface as affected by temperature, pH and time

The adhesion of Bacillus cereus to stainless steel was modelled as a function of pH (4.0-8.0), time (2-24h) and temperature (4.0-36.0°C) using response surface methodology. Based on the initial inoculum (3 or 6 log cfumL^-1), two equations describing B.cereus adhesion to stainless steel were obtained. The results indicated that B.cereus was able to reach up to 5.5cfucm^-2 and 6.4cfucm^-2 when the initial inocula were 3 log cfumL^-1 and 6 log cfumL^-1, respectively. The significance of the factors varied with the model; i.e., inoculum of 3 or 6 log cfumL^-1. Bias and accuracy factors showed that the models are adequate to predict B.cereus adhesion to stainless steel surface under conditions assessed and to assess the adhesion of B.cereus under a range of conditions to which this microorganism can be exposed during either milk processing or cleaning procedures.