Abstract
The presence of biofilms on food processing surfaces is a constant concern and can cause economic damage and impacts on public health. The aim of this work was to evaluate the development of P. fluorescens on the stainless steel surface, to analyze the CIP (clean in place) hygiene considering different geometries, to investigate the flow fluid dynamics and to determine the consumption of the inputs in this process. A circulation line with the characteristics of a dairy was used. The surface sampling was done using the swab technique and the performance of the process was evaluated based on decimal reductions considering the initial population adhered. The fluid dynamics study was carried out with FLUENT software and the consumption was determined by means of flow and electric current sensors. The results showed that P. fluorescens adhered to the surface reaching an average of 4.31 ± 0.26 log CFU∙cm-2, with the production of exopolysaccharides during usual time of industry operation. The decimal reduction was not significantly different among the pipe geometries in straight section, elbow, expansion and reduction. The stretch with branching in tee was statistically different from the others due to a zone of stagnation and fluid recirculation. The rinses were the stages that consumed the most water and the alkaline cleaning demanded more energy to execute the CIP. The geometries showed microbiological safety after CIP process, except tee. In addition, the expressive demand for water and energy for the execution of the process was evident.
Highlights
Biofilms are a community of microorganisms, adhered to the surface and embedded by a protective slime
The objective of this work was to investigate the contamination caused by P. fluorescens on the surface of stainless steel pipes in contact with milk, to evaluate the CIP hygiene procedure considering five different geometries commonly found in industrial processing units
After the P. fluorescens incubation period in the studied geometries, the contamination produced on the stainless steel surface was 4.31 ± 0.26 log CFU∙cm-2
Summary
Biofilms are a community of microorganisms, adhered to the surface and embedded by a protective slime. This system consists of cells, exopolymers and residual food. Pseudomonas fluorescens stands out with the potential for deterioration and loss of food produced (Ge et al, 2017). This species is able to grow at low temperatures, produce exopolysaccharides and cause changes in the structure and color of foods due to the production of lecithinase (phospholipase C), proteolytic enzymes and pigmented molecules (Rossi et al, 2016)
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call