Indicadores de resultados inmediatos

1. Viable cell counts will still be used. It is the firm belief of the author that viable cell counts (total aerobic count, anaerobic count, coliform/E. coli count, differential count, and pathogenic count) will remain an important parameter to assess the potential safety and hygiene quality of food supplies.

2. Real-time monitoring of hygiene will be in place. Several exciting developments in this area have occurred, such as ATP bioluminescence, catalase measurement,

and instant protein detection kits. Recently, BioControl (Bellevue, WA) introduced a protein testing kit called FLASH, which can detect the presence of protein on food contact surfaces almost instantaneously. Positive surfaces change the color of the swab from yellow to green/blue in 5 s. This system has been validated in the author’s labo- ratory (Olds et al. 2005). This type of real-time monitoring system will be developed for other compounds in the future.

3. PCR, ribotyping, and genetic tests will become a reality in food laboratories. 4. ELISA and immunological tests will be completely automated and widely used.

After pre-enrichment of food samples (overnight incubation or 8 h incubation), an analyst can place the sample into an automated system and monitor the presence of the target pathogen in a matter of 1 to 2 h. Automated systems will continue to be developed and used in the future.

5. Dip stick technology will provide rapid answers. Many forms of dip sticks are available for screening of pathogens by “lateral” migration of an antigen-antibody complex. These kits can detect target organisms in about 10 min after enrichment of the cultures overnight. This type of technology will continue to be developed and used in the future.

6. Biosensors will be in place for HACCP programs. A variety of biosensors are now available on the market to monitor microbes, but they are not yet suitable to use in routine monitoring of pathogens in the food industry. More research and development will be needed to have this technology in place for the food industry.

7. Instant detection of target pathogens will be possible by a computer-generated matrix in response to particular characteristics of pathogens. Microarrays, micro- chips, and nano technology will be gaining importance in food microbiology in the near future.

8. Effective separation and concentration of target cells will greatly assist in rapid identification. A variety of approaches have been mentioned in this chapter. These developments will continue to improve detection sensitivity and speed of detection of target pathogens

9. A microbiological alert system will be in food packages. It is conceivable that a series of reagents in the form of “bar codes” will be placed inside packaging materi- als and will change color due to the development of gas (ammonia, hydrogen sulfide, hydrogen, carbon dioxide, etc.), acid, or extremes in temperature to indicate a potential spoilage problem.

10. Consumers will have rapid alert kits for pathogens at home. Nowadays there are urine, blood glucose, pregnancy, and even AIDS test kits available for the consumer to use at home. It is possible that rapid alert kits for food spoilage and even food pathogen detection will be developed for home use (Fung 2002b).

In conclusion, the future looks very bright for the field of rapid methods and automation in microbiology. The potential is great, and many exciting developments will certainly unfold in the near and far future.

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Acknowledgments

This material is based upon work supported by the Cooperative State Research, Education, and Extension Service, U.S. Department of Agriculture, under agreement No. 93-34211- 8362. Contribution No. 06-2-14, Kansas Agricultural Experimental Station, Manhattan, Kansas.

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Molecular Technologies for Detecting and