Practical and theoretical considerations for the use of bacteriophages in food systems.

Bacteriophages represent a promising antibacterial technology that may be useful in the control of a wide variety of nuisance and pathogenic bacteria. One area that is garnering increasing interest is the use of phages for the control of bacteria—particularly food-borne pathogens—in food systems. This chapter discusses factors such as the stability of the phages, the state of the bacteria, or the ability of phages to access their hosts, in the context of theory, as well as empirical data from model phage-host systems and from trials of phage biocontrol in foods. The phage adsorption rate constant plays a major role in the rate at which phage adsorb to susceptible bacteria. In the case of the control of food-borne pathogens, phages present a viable option, as the diversity of pathogens requiring control is limited to relatively few bacterial species. In contrast, the use of phages as a general antimicrobial strategy in foods is severely restricted simply by the diversity of potential target bacteria in a given open environment. Biofilms are a topic of perennial concern in the food industry, as they can cause problems in food production facilities ranging from equipment fouling to the shedding of pathogenic microbes into food products. Minimally processed foods which are considered to be at risk from contamination by a narrow spectrum of food-borne pathogens, and which are also intrinsically conducive to bacterial and phage survival, could be the most promising initial candidates for phage-based biocontrol.