Detection and Control of Food Borne Bacterial Pathogens 2024 PDF

Detection and Control of food borne bacterial pathogens Dr. Muhammad CERTIFIED FOOD PhD, MBA, MSc Naseem Khan SAFETY PROFESSIONAL  2 MICROBIOLOGICAL CRITERIA FOR FO...

Detection and Control of food borne bacterial pathogens Dr. Muhammad CERTIFIED FOOD PhD, MBA, MSc Naseem Khan SAFETY PROFESSIONAL  2 MICROBIOLOGICAL CRITERIA FOR FOODSTUFFS April 18, Food Microbiology 2024  3 Codex Standards of Meat and Poultry Products April 18, Food Microbiology 2024  4 Standards According to ISO, standards are documented agreements containing technical specifications or other precise criteria to be used consistently as rules, guidelines or definitions, to ensure that materials, products, processes and services are fit for their purpose (ISO) Standard is a part of a law or regulation that is enforceable by the regulatory agency having jurisdiction (ICMSF) ICMSF : International Commission on Microbiological Specifications for Foods ISO : International Organization for Standardization April 18, Food Microbiology 2024  5 Product Standards Product standards are specifications and criteria for the characteristics of products e.g., Meat April 18, Food Microbiology 2024  6 The Codex definition of a microbiological criterion (1) A statement of the organisms of concern and/or their toxins (2) The analytical methods for their detection and quantitation, (3) Sampling plan, including when and where samples are to be taken (4) Microbiological limits considered appropriate to the food (5) The number of sample units that should conform to these limits.  These five components are embodied in a sampling plan. April 18, Food Microbiology 2024  7 Testing Microorganism for Meat  Indicator tests Indicator organisms are groups of bacteria that indicate the possible presence of organisms of concern, and may point to the origins of microbial contamination.  Organisms of concern or Pathogens: Pathogens causing food borne infection: Salmonella, Listeria monocytogenes, Shiga toxin-producing Escherichia coli (STEC). Pathogens causing food borne intoxication: Bacillus cereus, Staphylococcus aureus and Clostridium perfringens cause illness through intoxication. April 18, Food Microbiology 2024  8 Microbiological criteria for Meat  Food safety criteria: If exceeded, indicate that the batch tested is unsatisfactory and should be removed from or not placed on the market.  Process hygiene criteria: The results provide an indication of performance and control of the slaughter, dressing and production process at the time of sampling, and must be used accordingly. Failure to meet either class of criteria should always result in an investigation to find the cause of contamination and action taken to prevent contamination of future production. April 18, Food Microbiology 2024  9 Demonstration of compliance Demonstration of compliance with process hygiene criteria for meat and processed meat is required as follows: Aerobic Plate Count Yeast and Mold Count Escherichia coli Staphylococcus aureus (Coagulase +ve) April 18, Food Microbiology 2024  10 Demonstration of compliance Demonstration of compliance with food safety criteria for meat and processed meat is required as follows: Salmonella Listeria monocytogenes Sulphite Reducing Clostridia Clostridium botulinum Campylobacter Spp* April 18, Food Microbiology 2024  11 Sampling plan  The sampling plan summarizes the requirements (limits) and defines their stringency. It is the basis for the decision on release / acceptance of tested lots.  Sampling plans are expressed by 3 or 4 parameters  ICMSF has suggested 2 and 3 class sampling plans ICMSF : International Commission on Microbiological Specifications for Foods April 18, Food Microbiology 2024  12 Sampling plan 1. Two class plan/two attribute scheme:  Two attributes, i.e., presence or absence of an organism in a given sampling unit.  Applied for more hazardous organisms. e.g. Clostridium botulinum. 2. Three class plan: are frequently used to examine for hygiene indicator where enumeration of microbes in a unit volume or mass is possible. Such plans can be used to separate the quality of a lot into acceptable, marginally acceptable and unacceptable April 18, Food Microbiology 2024  13 Sampling plan The terms n, c, m and M used in this standard have the following meaning: n = number of samples or units analyzed. c = maximum allowable number of sample units yielding marginal results, i.e. results between m and M. m = microbiological level that separates good quality from defective, or in a three-class plan good from marginally acceptable quality. M = microbiological level in a three class plan that separates marginally acceptable from unacceptable (defective) quality. April 18, Food Microbiology 2024  14 Sampling plan 2-Class Sampling Plan 3-Class Sampling Plan (where n, c and m are specified) (where n, c, m and M are specified) 1. Satisfactory, if all the values 1. Satisfactory, if all the values observed are ≤ observed are ≤ m m 2.Unsatisfactory, if one or more of 2. Acceptable, if a maximum of c values are the values observed are >m or more between m and M and the rest of the values than c values are > m are observed as ≤ m 3. Unsatisfactory, if one or more of the values observed are >M or more than c values are > m April 18, Food Microbiology 2024  15 The stringency of microbiological specifications  The choice of n and c varies with the desired stringency.  This stringency is guided by the level of risk associated with the material is to be used/processed/consumed.  For high stringency n is high and c is low.  Choice of n is usually a compromise between what is an ideal probability of acceptance and the work load the laboratory can handle as sampling plans should be administratively and economically feasible. April 18, Food Microbiology 2024  16 Dairy Products GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  17 Meat, Poultry and its Products GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  18 Fish and Shellfish their Products GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  19 Egg and Egg Products GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  20 Tomato Concentrates, Sauces, Vinegar, Spices and Herbs GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  21 Cereals; Legumes and their Products GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  22 Fruit and Vegetables GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  23 Jelly, Jam and Marmalade GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  24 Chocolate, Sweets and their Ingredients GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  25 Ready to Eat Foods GSO STANDARD GCC Standardization Organization Microbiological criteria for foods and food ingredients Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) April 18, Food Microbiology 2024  26 Control of food borne bacterial pathogens April 18, Food Microbiology 2024  27 Control of food borne bacterial pathogens  Pathogens and microbial toxins  Hygiene indicators  Aerobic colony counts April 18, Food Microbiology 2024  28 Ready-to-Eat Food  Cooking before consumption  Reheating before consumption  Washing before consumption April 18, Food Microbiology 2024  29 Single Samples  Taking single samples is considered a practical approach for official sampling because multiple samples from the same batch of food may not be available, particularly when food is sampled at retail level.  Sampling by food business operators April 18, Food Microbiology 2024  30 Analytical Method  It is important that the analytical method used is able to detect the microorganism of concern in the food being tested. Where possible, laboratories should use methods which have been validated for the food commodity concerned by international organizations April 18, Food Microbiology 2024  31 Analytical Method  ISO www.iso.org  AFNOR www.afnor.org  MICROVAL www.microval.org  NORDVAL www.nmkl.org  FDA BAM www.fda.gov April 18, Food Microbiology 2024  32 Interpreting Results  Satisfactory means the test results indicate the food sample meets with the guideline limit.  Borderline means that the test results indicate the food sample meets the guideline limit, but that it may be approaching unsatisfactory.  Unsatisfactory means that the test results indicate the sample of food exceeds the guideline limit. If the result of a pathogen or microbial toxin test is unsatisfactory, the ready-to-eat food is considered unsafe to eat. April 18, Food Microbiology 2024  33 Interpreting Results  For some test parameters, test results will either be ‘satisfactory’ or ‘unsatisfactory’, with no ‘borderline’ result. For example, Salmonella test results are either satisfactory (Salmonella not detected) or unsatisfactory (Salmonella detected). There is no ‘borderline’ result for a Salmonella test. April 18, Food Microbiology 2024  34 Sample Designation Samples are designated according to the complete set of microbiological test results associated with each sample for each parameter  If the results for all microbiological parameters tested for a sample are satisfactory, the overall designation for that sample is Satisfactory  If the result for one or more microbiological parameters tested for a sample is borderline, the overall designation for that sample is Borderline April 18, Food Microbiology 2024  35 Sample Designation Samples are designated according to the complete set of microbiological test results associated with each sample for each parameter  If the result of one or more microbiological parameters tested for a sample is unsatisfactory, the overall designation for that sample is Unsatisfactory. If the result of a pathogen or microbial toxin test is unsatisfactory, the ready-to-eat food is considered unsafe to eat  If the result of one or more microbiological parameters tested for a sample is borderline, and the result of one or more microbiological parameters tested for that same sample is unsatisfactory, the overall designation for that sample is Unsatisfactory. If the result of a pathogen or microbial toxin test is unsatisfactory, the ready-to-eat food is considered unsafe to eat April 18, Food Microbiology 2024  36 PATHOGENS AND MICROBIAL TOXINS Guideline limits for certain pathogens and microbial toxins in ready-to-eat food placed on the market April 18, Food Microbiology 2024  37  Borderline results are applicable to four PATHOGENS AND pathogens listed in this Guidance Note: MICROBIAL TOXINS Borderline Results 1. Bacillus cereus and other pathogenic Bacillus species 2. Clostridium perfringens 3. Coagulase positive staphylococci 4. Vibrio parahaemolyticus April 18, Food Microbiology 2024  38 PATHOGENS AND MICROBIAL  For most pathogens and microbial toxins, TOXINS their presence in a ready-to-eat food is unsatisfactory and presents risk to health. Unsatisfactory The result of testing being categorized Results as: 1. Satisfactory (not detected) 2. Unsatisfactory (detected) April 18, Food Microbiology 2024  39 PATHOGENS AND MICROBIAL TOXINS Action required when results of pathogen or microbial toxin tests are borderline April 18, Food Microbiology 2024  40 PATHOGENS AND MICROBIAL TOXINS Action required when results of pathogen or microbial toxin tests are borderline April 18, Food Microbiology 2024  41 PATHOGENS AND MICROBIAL  For most pathogens and microbial toxins, TOXINS their presence in a ready-to-eat food is unsatisfactory and presents risk to health. Unsatisfactory The result of testing being categorized Results as: 1. Satisfactory (not detected) 2. Unsatisfactory (detected) April 18, Food Microbiology 2024  42 PATHOGENS AND MICROBIAL TOXINS Action required when results of pathogen or microbial toxin tests are borderline AND Unsatisfactory April 18, Food Microbiology 2024  43 Reference Laboratory Testing Specialist or reference tests are available which help provide extra information on foodborne pathogens. These tests are usually performed in specialist or national reference laboratories in order to:  Verify the results from a primary laboratory  Detect more unusual pathogens, viruses and parasites  Detect toxins, or the genes for toxin production  Perform typing of isolates, e.g. serotyping, phage typing, antimicrobial resistance typing or genetic fingerprinting  Assess the pathogenic potential of an isolate April 18, Food Microbiology 2024  44  An unsatisfactory result for a hygiene indicator test does not mean that the batch of food is considered HYGIENE unsafe. INDICATORS  However, unsatisfactory results represent unsatisfactory levels of microbial contamination and indicate that pathogens may be present. Unsatisfactory Results  The food business operator should investigate the cause of the elevated levels and take measures as part of their HACCP-based procedures and GHP to in order to ensure levels in subsequent batches of food are satisfactory.  For borderline results, the action carried out should be proportional to the levels detected. April 18, Food Microbiology 2024  45 HYGIENE INDICATORS Guideline limits for certain indicator microorganisms in ready-to-eat foods sampled when placed on the market April 18, Food Microbiology 2024  46 HYGIENE INDICATORS Table 5. Action required when results of hygiene indicator tests are unsatisfactory or borderline April 18, Food Microbiology 2024  47 The aerobic colony count (ACC) limits for various AEROBIC COLONY COUNTS categories of ready-to-eat food. The ACC test is a generic test that counts organisms which grow under aerobic conditions at mesophilic temperatures on a particular growth medium. The counts provide useful information to assess a food’s quality or its remaining shelf-life. April 18, Food Microbiology 2024  48 The ACC test cannot be used to assess the safety of food. An unsatisfactory result for the ACC AEROBIC test does not mean that the batch of food is COLONY COUNTS considered unsafe. However, an unsatisfactory result represents Action unsatisfactory levels of microbial contamination. required for The food business operator should investigate the Borderline or cause of the elevated levels and take measures Unsatisfactory as part of their procedures based on HACCP and GHP Results in order to return levels in subsequent batches of food to satisfactory levels. April 18, Food Microbiology 2024  49 1. Review cooking times/temp. to ensure adequate heat treatment AEROBIC 2. Review refrigeration times/temp. to ensure adequate refrigeration COLONY COUNTS 3. Review the shelf-life they set to check that it is appropriate 4. Review selection and origin of raw materials Action 5. Review cleaning and sanitizing procedures to ensure they are required for effective Borderline or 6. Review staff hygiene practices to ensure they are adequate 7. Review staff training to ensure that staff are appropriately trained Unsatisfactory 8. Review and update their procedures based on HACCP and GHP Results 9. Test further samples of food and samples from the food preparation environment April 18, Food Microbiology 2024  50 AEROBIC COLONY COUNTS Guidance on the interpretation of results for ACC in ready-to-eat foods when placed on the market April 18, Food Microbiology 2024  51 AEROBIC COLONY COUNTS Guidance on the interpretation of results for ACC in ready-to-eat foods when placed on the market April 18, Food Microbiology 2024  52 AEROBIC COLONY COUNTS Guidance on the interpretation of results for ACC in ready-to-eat foods when placed on the market April 18, Food Microbiology 2024  53 AEROBIC COLONY COUNTS Guidance on the interpretation of results for ACC in ready-to-eat foods when placed on the market April 18, Food Microbiology 2024  54 AEROBIC COLONY COUNTS Guidance on the interpretation of results for ACC in ready-to-eat foods when placed on the market April 18, Food Microbiology 2024  55 THANK YOU April 18, Food Microbiology 2024