As indicated earlier, control of pathogen requires adherence to GMPs, compliance with valid HACCP plans, and perhaps use of specific antimicrobial agents. The need for and effectiveness of these programs is assessed through microbiological information (criteria). Therefore, microbiological testing, while not a control measure per se, is an essential com- ponent of a processor’s overall pathogen control strategy. Microbiological testing involves assessment of product and the processing environment. Product testing allows an assess- ment of the overall microbiological load, incidence of pathogens, effects of processing pro- cedures on pathogen load, adherence to regulatory performance standards or criteria, etc. Through these types of microbiological assessments, processors can more reliably identify and assess the microbial hazards in their products and processes, as well as validate their measures used for pathogen control. Environmental testing is used primarily to assess the effectiveness of sanitation programs and other facility-wide programs designed for micro- bial control.
Depending on the objective of the microbiological analysis, there are specific sampling plans and methods that can be used. Sampling is a key issue. Because it is not possible to analyze 100% of a given production lot of final product or the entire processing environ- ment, samples that are representative of the entire lot must be obtained and analyzed. Sampling plans are based on statistical probability, and therefore provide confidence when interpreting results. Furthermore, the part of the sample that is actually subjected to the analytical procedure, referred to as an analytical unit, must also be representative of the whole sample. Whole carcass rinse samples are used for broilers, swab samples are collected for turkeys, and a sample of defined volume is collected for ground or portioned product. Both qualitative and quantitative methods are utilized in poultry processing to analyze samples. Qualitative methods provide a “yes/no” answer regarding the presence of specific bacterial types in the sample, while quantitative methods provide an estimate of the number of specific bacterial types. Again, defined procedures are to be followed when microbiologically evaluating product or environmental samples.
With the establishment of USDA-FSIS performance standards and criteria for poultry products, microbiological testing has taken on more importance in the processing of safe poultry products. At present, raw whole and ground products must meet Salmonella per- formance standards, carcasses must meet Biotype I E. coli criteria, and cooked poultry products must meet lethality, stabilization, and L. monocytogenes performance standards. Salmonella performance standards are used by USDA-FSIS as a means to determine the validity of a processor’s HACCP plan. The E. coli criteria are used as an indicator of control of fecal contamination (a primary source of pathogenic bacteria) in slaughter operations. Lethality, stabilization, and L. monoctyogenes performance standards are used to establish that the processor’s cooking, cooling, and post-process handling procedures are valid for producing a safe product.
To remain in compliance with current regulatory requirements and to ensure produc- tion of safe products, poultry processors must establish an ongoing microbiological testing program. The testing program should be integrated into the plant’s normal operations so
that trends can be detected such that preventive measures can be taken in a timely manner. The nature of the microbiological testing program will be a function of the processor’s overall food safety objectives. These objectives should reflect the demands of the proces- sor’s customers as well as regulatory compliance.
Conclusion
Live poultry arriving at the processing plant harbor a heavy load of microorganisms. Most of these microorganisms are not harmful; however, poultry are known to harbor a number of bacteria that are pathogenic to humans. Typically, these occur in low levels, and only pose a threat to the consumer if the product is not handled in a safe manner. Regardless, it is the goal of the poultry processor to produce product with as low a level of pathogens as possible, which represents the acceptable level of safety based on product type. A compre- hensive approach to food safety, which encompasses adherence to GMPs, HACCP, the use of specific antimicrobial treatments, and a microbiological testing program, is required to produce final products that are safe for the consuming public.
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