Effect of microbial sanitizers for reducing biofilm formation of Staphylococcus aureus and Pseudomonas aeruginosa on stainless steel by cultivation with UHT milk

Biofilm is a serious issue in the dairy factory due to it increases the opportunity for microbial contamination. Staphylococcus aureus and Pseudomonas aeruginosa are the bacteria capable to construct the biofilm on materials and equipments. Therefore, the bacterial growth and efficiency of sanitizing agents to solve the problems were evaluated. These bacteria grew well in UHT milk when they were cultivated at 37 degrees C, especially S. aureus. The exponential growth phase and biofilm on stainless steel were discovered by short contact time at 2h. The mature stage of biofilm cycle was found at 4h during bacteria growth and it was continuously constructed until 48h. The 10, 24, and 48h-old biofilm adhering on stainless steel were established with oxisan and chlorine used as microbial sanitizers. The 4% of sanitizing agents was the efficiency concentration to reduce biofilm on stainless steel up to 82% when these bacteria grew in UHT milk.