USE OF ANTIBODY-LINKED PROBES FOR IMMUNO-LOCATION OF MICROORGANISMS IN FOOD SYSTEMS

The growth of microorganisms in foods is different from that in axenic liquid culture in laboratory media. In natural environments, includin g food, microorganisms generally grow in mixed culture and in close pr oximity to each other, as a result of which antagonistic or synergisti c interactions can occur. In addition, most foods are solids, with the consequence that organisms are spatially fixed and will only grow at sites that provide the correct growth conditions. At different sites w ithin foods there are differences in pH, oxygen concentration, nutrien t level, water activity and also, in some foods, preservatives. This r esults in the establishment of a series of micro-environments, only so me of which will provide appropriate conditions for growth. Antibody-l inked probes can be used for the immune-location of microorganisms or their products in natural food systems to demonstrate the sites at whi ch growth has occurred, and thereby suggest methods of reducing microb ially produced spoilage. In this study, the use of antibodies raised a gainst species of Pseudomonas, Brochothrix thermosphacta, and nisin pr oduced by Lactococcus lactis are discussed.