Biofouling in food processing: Biofilm or biotransfer potential?

Abstract

The presence of viable microorganisms on a surface presents a 'biotransfer potential'. These microorganisms may be actively multiplying and colonizing the surface, or may be merely surviving, retaining viability but being unable to multiply due to adverse environmental conditions. Attached microorganisms may be retained in surface features, mixed with organic material (food debris/soil) or detergent debris. Microorganisms which are multiplying on a surface may be termed a 'biofilm' - although the most well-recognized definition of a biofilm indicates the presence of a matrix of extracellular polymeric substances, a flowing aqueous environment and a solid-liquid interface, and hence may not be entirely applicable to all microorganisms on surfaces. It is therefore perhaps preferable to consider a given environment in terms of biotransfer potential, then to consider the mode in which microorganisms are present in order to develop appropriate models for monitoring and control procedures. The focus of this paper is on the diversity of forms in which the biotransfer potential may be presented, the aim being to recognize the limitations of the definition of the term biofilm, and the problems which might arise as a result of this misnomer.