Food Protection Trends - August 2009 - 499

on available heat resistance data, then additional studies or process re-design would be warranted. – Available scientific guidance, such as the naCmCF guidance on parameters for performing an inoculated pack/challenge study (45), should be used for validation of control measures through microbiological challenge testing. – Microbiological expertise is necessary to determine the relevance and validity of applying published data to a specific product and process. an experienced microbiologist or process authority should assist in the use and interpretation of published data. ❏ Consider both thermal and nonthermal control measures, with validation, to eliminate Salmonella. – Thermal processing can be used under dry or moist conditions. moist heat treatment is followed by a drying step in the manufacturing of many low-moisture products. Where appropriate (e.g., for some spices and seeds) a combination of steam treatment (pressurized or non-pressurized) and drying may be used to inactivate Salmonella. in such cases, validation should focus on determining the lethality of the steam process alone as a conservative scenario or, if heating after the steam process is included in lethality calculations, the combined effects of the multiple processing steps should be validated. – Validation should focus on the CCp used to deliver the target log reduction, when one of multiple steps effecting lethality is chosen as the CCp. Cumulative effect from multiple inactivation steps may be used to achieve the target log reduction, even though individual steps alone are not sufficient to achieve the target lethality, as long as the individual processing steps and the combined lethality are validated. be aware that not all heating steps in a process will provide Salmonella inactivation. For example, spray drying is an evaporative cooling process that usually does not result in appreciable inactivation. another example of minimal to no Salmonella inactivation may be a finishing dryer following the heat extrusion process. – For a low-moisture product (e.g., spray-dried milk) that starts with high-moisture ingredients (e.g., milk), the heat treatment process prior to drying should be readily verifiable, and efforts should be concentrated on preventing post-lethality contamination during drying and the subsequent steps through finished product packaging. – Examples of non-thermal control measures are treatment with an approved chemical for fumigation, such as propylene oxide or ethylene oxide, and treatment with irradiation. ❏ once the lethality of the process is validated by scientific data, it should be ensured that the operation can deliver the critical limits and that the parameters are consistently met, through in-plant validation, which is an integral part of the validation process. Subsequently, verification of process control may include activities such as records review, calibration of instruments, and periodic finished product testing or other type of independent checks. ❏ it should also be ensured that raw material/ingredient suppliers validate their processes and the control measures. SALMONELLA CONTROL ELEMENT 7: ESTABLISH PROCEDURES FOR VERIFICATION OF SALMONELLA CONTROLS AND CORRECTIVE ACTIONS the adequacy of the Salmonella control program should be verified on an ongoing basis to assure effectiveness and to drive continuous improvement. Verification should focus on implementing a robust environmental monitoring program that has been designed to identify transient and/or resident Salmonella in the processing areas. appropriate corrective action procedures must be developed to address positive Salmonella findings with the intent of containing the contamination, identifying the potential source, and eliminating the problem. this section focuses on environmental monitoring and corrective actions to be taken when Salmonella is found in the environment, since this is one of the most important verification activities in low-moisture product manufacturing. other verification activities, such as those for critical control points in a haCCp system, are well covered elsewhere (9, 33, 43, 51). environmental monitoring is an essential component for Salmonella control, as it provides a microbiological assessment of a plant’s environment and an assessment of the effectiveness of sanitation and the overall Salmonella control program (27, 40, 59). environmental monitoring is not, in itself, a control measure. rather, it is a tool to verify the effectiveness of the overall Salmonella control program. monitoring results provide critical information to improve Salmonella control in the plant environment; this information should be used to correct problem areas before they pose a risk to finished product. With this understanding, it is critical that the program be designed and implemented so as to maximize detection of Salmonella. a robust environmental monitoring program is one of many prerequisite programs that together provide a firm foundation for effective food safety management. the target organism for environmental monitoring for low-moisture foods should be Salmonella. Scientific literature suggests that the pathogen is more persistent in the environment than other organisms such as coliforms and enterobacteriaceae. a suitable indicator for Salmonella has not been identified (19). testing with enumeration of enterobacteriaceae, however, may help assess moisture control in areas in the processing environment intended to remain dry (30). enterobacteriaceae is a useful indicator of process hygiene and may be monitored in parallel as a hygiene indicator for verification of general sanitation effectiveness. however, it cannot be a substitute for the direct monitoring of Salmonella because, while high levels of enterobacteriaceae suggest an increased risk for the presence of Salmonella, low levels of enterobacteriaceae do not guarantee absence of the pathogen (15, 19). environmental monitoring for Salmonella is generally conducted on nonproduct contact surfaces (non-pCSs). non-pCSs in the primary Salmonella Control area (pSCa) should be the main focus of routine monitoring for Salmonella. however, environmental monitoring for Salmonella should also be conducted in other areas of the facility (e.g., wet processing or handling of raw materials). AUGUST 2009 | FOOD PROTECTION TRENDS 499

Food Protection Trends - August 2009

Table of Contents for the Digital Edition of Food Protection Trends - August 2009