9/9/2016 Food Learning Objectives 1.Differentiate among the various microbiological criteria in foods 2.Identify national and international agencies involved in Chapter 6 AN INTRODUCTION establishing microbiological criteria 3. Recognize how indicator organismsare used in Indicator microbiological criteria Microorganisms and 4.Understand why some sampling plans are more stringent than others Microbiological 5.Identify organisms and types of foods for which zero Criteria tolerance has been established 6.ro Microbiological Criteria in Foods Purpose of Microbiological Criteria in Foods Microbiological criteria are tools used in To ensure that a product has been assessing the safety and quality of foods produced under sanitary conditions and A microbiological criterion defines the is microbiologically safe to consume acceptability of a product or a food lot, Microbes are found in most raw and based on the absence or presence,or finished food products number of microorganisms including Certain bacteria,even we're not parasites,and/or quantity of their pathogens,may be safe ALL BAD toxins/metabolites,per unit(s)of mass, volume,area or lot in food,depending on the food product
9/9/2016 1 Chapter 6 Indicator Microorganisms and Microbiological Criteria Learning Objectives 1. Differentiate among the various microbiological criteria in foods 2. Identify national and international agencies involved in establishing microbiological criteria 3. Recognize how indicator organisms are used in microbiological criteria 4. Understand why some sampling plans are more stringent than others 5. Identify organisms and types of foods for which zero tolerance has been established 6. Identify and list steps required to manage microbiological hazards in foods Microbiological Criteria in Foods • Microbiological criteria are tools used in assessing the safety and quality of foods • A microbiological criterion defines the acceptability of a product or a food lot, based on the absence or presence, or number of microorganisms including parasites, and/or quantity of their toxins/metabolites, per unit(s) of mass, volume, area or lot Purpose of Microbiological Criteria in Foods To ensure that a product has been produced under sanitary conditions and is microbiologically safe to consume • Microbes are found in most raw and finished food products • Certain bacteria, even pathogens, may be safe in food, depending on the food product
9/9/2016 Purpose of Microbiological Criteria in Foods Microbiological criteria are used to assess: To distinguish between acceptable and unacceptable 1.Safety of food products or food-processing practices 2.Adherence to good manufacturing Numbers and types of microbes associated with practices (GMPs) foods may be used to judge safety and quality 3.Shelf life of perishable foods Safety-absence,presence,or level of pathogens and their toxins and the expected control or 4.Suitability of a food or ingredient for destruction of them a particular purpose Spoilage-level of spoilage microbes and their control measures reflects food quality Microbiological criteria ensure the safety Indicator organisms may be used to assess and quality of foods microbial quality or safety Assessing a Need for Microbiological Criteria Microbiological Criteria Include 1.Evidence of a health hazard based on 1.A statement identifying the food and the epidemiological data or a hazard analysis microbe and/or toxins of concern 2.Nature of the food's normal microbial makeup 2.Lab methods for detection and 3.Ability of the food to support microbial growth quantification of each microbe of concern 4.Effect of processing on the microflora of the food 3.Sampling plan 5.Potential for microbial contamination and/or 4.Microbiological limits for the food growth during processing,handling,storage,and distribution 5.Number of samples required to confirm these limits 6.Spoilage potential and GMPs 2
9/9/2016 2 To distinguish between acceptable and unacceptable products or food-processing practices • Numbers and types of microbes associated with foods may be used to judge safety and quality • Safety - absence, presence, or level of pathogens and their toxins and the expected control or destruction of them • Spoilage – level of spoilage microbes and their control measures reflects food quality • Indicator organisms may be used to assess microbial quality or safety Purpose of Microbiological Criteria in Foods Microbiological criteria are used to assess: 1. Safety of food 2. Adherence to good manufacturing practices (GMPs) 3. Shelf life of perishable foods 4. Suitability of a food or ingredient for a particular purpose Microbiological criteria ensure the safety and quality of foods Assessing a Need for Microbiological Criteria 1. Evidence of a health hazard based on epidemiological data or a hazard analysis 2. Nature of the food’s normal microbial makeup 3. Ability of the food to support microbial growth 4. Effect of processing on the microflora of the food 5. Potential for microbial contamination and/or growth during processing, handling, storage, and distribution 6. Spoilage potential and GMPs Microbiological Criteria Include 1. A statement identifying the food and the microbe and/or toxins of concern 2. Lab methods for detection and quantification of each microbe of concern 3. Sampling plan 4. Microbiological limits for the food 5. Number of samples required to confirm these limits
9/9/2016 Mandatory or Advisory Criteria 3 Categories of Criteria Mandatory criterion-may not be ·Mandatory exceeded Failure to comply is a violation sub ject to Food that does not meet the specified enforcement policy limit is required to be rejected, Guideline:used by the food industry or regulatory destroyed,reprocessed,or diverted agency to monitor a manufacturing practice Serve as an alert mechanism Advisory criterion-permits acceptable Assess processing efficiency judgments to be made ·Advisory Serves as an alert to deficiencies in Specifications:used as a purchase require processing,distribution,storage,or marketing Mandatory or advisory Who Establishes Microbiological Criteria? .Various scientific organizations develop general 1981-Codex Alimentarius program principles for the application of microbiological criteria formulated General Principles for the Those that have most affected the food industry Establishment and Application of Microbiological Criteria r90 International Food Standards Program .1984-regulatory agencies requested 2.International Commission on Microbiological formulation of general principles for the Specifications for Foods application of microbiological criteria to 3.US National Academy of Sciences food and food ingredients 4.US National Advisory Committee on Microbiological Criteria for Foods
9/9/2016 3 Mandatory or Advisory Criteria Mandatory criterion – may not be exceeded • Food that does not meet the specified limit is required to be rejected, destroyed, reprocessed, or diverted Advisory criterion – permits acceptable judgments to be made • Serves as an alert to deficiencies in processing, distribution, storage, or marketing 3 Categories of Criteria Standard: part of a law, ordinance, or administrative regulation • Mandatory • Failure to comply is a violation subject to enforcement policy Guideline: used by the food industry or regulatory agency to monitor a manufacturing practice • Serve as an alert mechanism • Assess processing efficiency • Advisory Specifications: used as a purchase requirement whereby conformance becomes a condition of purchase between buyer and vendor • Mandatory or advisory Who Establishes Microbiological Criteria? • Various scientific organizations develop general principles for the application of microbiological criteria • Those that have most affected the food industry 1. Joint Food and Agricultural Organization and World Health Organization Codex Alimentarius International Food Standards Program 2. International Commission on Microbiological Specifications for Foods 3. US National Academy of Sciences 4. US National Advisory Committee on Microbiological Criteria for Foods • 1981 – Codex Alimentarius program formulated General Principles for the Establishment and Application of Microbiological Criteria • 1984 – regulatory agencies requested formulation of general principles for the application of microbiological criteria to food and food ingredients
9/9/2016 Codex Alimentarius Sampling Plans Includes both sampling procedure and decision criteria Collection of internationally recognized standards,codes of practice,quidelines, To examine food for microbes a representative sample is examined by defined methods and other recommendations relating to Impractical to examine an entire food lot foods,food production,and food safety (quantity of product produced,handled,and Standards for all foods in the form in stored within a limited time under uniform conditions) which they are delivered to the consumer -Statistical concepts of population probability processed,semi-processed,raw and sampling are used to determine the number WHO recommends its use to make all and size of sample units needed to provide standards similar conclusions Inferior lots are rejected Simple Example Types of Sampling Plans 10 samples tested for a microbe Two categories based on distribution of microbes in food Variables sampling plan The more samples examined,the -used if microbes have an even distribution in the food -analytical sample represents the entire lot(milk) Decision criteria lower the risk of making an incorrect decision about a lot quality maximum Attributes sampling plan (used more frequently) allowable positive Time-consuming and costly -used if microbes are not distributed evenly within the Compromise is made between the food samples is 2 number of samples and the risk -analytical samples may vary greatly -used if the microbe is present at low numbers used for food at ports of entry as little is known on how If >2 samples are If 2 or less is the food was processed positive,then the positive,then the -used to monitor performance relative to GMPs lot is rejected lot is accepted -NOT used if there is no defined lot or when random sampling is not possible 4
9/9/2016 4 Codex Alimentarius • Collection of internationally recognized standards, codes of practice, guidelines, and other recommendations relating to foods, food production, and food safety • Standards for all foods in the form in which they are delivered to the consumer – processed, semi-processed, raw • WHO recommends its use to make all standards similar Sampling Plans • Includes both sampling procedure and decision criteria • To examine food for microbes a representative sample is examined by defined methods - Impractical to examine an entire food lot (quantity of product produced, handled, and stored within a limited time under uniform conditions) - Statistical concepts of population probability and sampling are used to determine the number and size of sample units needed to provide conclusions - Inferior lots are rejected 10 samples tested for a microbe If >2 samples are positive, then the lot is rejected If 2 or less is positive, then the lot is accepted Decision criteria maximum allowable positive samples is 2 Simple Example - The more samples examined, the lower the risk of making an incorrect decision about a lot quality - Time-consuming and costly - Compromise is made between the number of samples and the risk Types of Sampling Plans Two categories based on distribution of microbes in food • Variables sampling plan - used if microbes have an even distribution in the food - analytical sample represents the entire lot (milk) • Attributes sampling plan (used more frequently) - used if microbes are not distributed evenly within the food - analytical samples may vary greatly - used if the microbe is present at low numbers - used for food at ports of entry as little is known on how the food was processed - used to monitor performance relative to GMPs - NOT used if there is no defined lot or when random sampling is not possible
9/9/2016 Two-Class Sampling Plan Two-Class Sampling Plan Almost exclusively used for pathogens-preferred when the organism of concern is not permitted in Decision criterion is based on food sample number of sample units-n Assigns the microbial concentration in the food to an -maximum allowable units with attribute class depending on whether it is above or unsatisfactory results-c below a preset concentration limit of the microbe(m) -microbiological limit-m c=max number of allowable unsatisfactory units accept all samples are sm accept all samples are s m lot lot eioteiese sc of n samples are >m s 2 of 5 samples are>m >c ofn samples are >m reject lot >2 of 5 samples are>m reject lot Three Class Sampling Plan Two microbiological limits are considered ·Hygiene indicators Attributes Plans m reflects the upper limit of GMP Two-class and Three-class ·2 marks the beyond which the level of contamination is hazar is or unacceptable Separates acceptable lots from marginally acceptable lots between m and M limits all samples are sm accept lot accept lo reject lot any sample is≥M eject lot Log countig 5
9/9/2016 5 n samples from the lot are tested all samples are ≤ m accept lot ≤ c of n samples are > m accept lot > c of n samples are > m reject lot Two-Class Sampling Plan • Almost exclusively used for pathogens - preferred when the organism of concern is not permitted in food sample • Assigns the microbial concentration in the food to an attribute class depending on whether it is above or below a preset concentration limit of the microbe (m) • c = max number of allowable unsatisfactory units 5 samples from the lot are tested all samples are ≤ m accept lot ≤ 2 of 5 samples are > m accept lot > 2 of 5 samples are > m reject lot Two-Class Sampling Plan • Decision criterion is based on - number of sample units – n - maximum allowable units with unsatisfactory results – c - microbiological limit - m Stringency is adjusted by changing the value(s) of c and/or n Three Class Sampling Plan Two microbiological limits are considered • Hygiene indicators • m reflects the upper limit of GMP • M marks the limit beyond which the level of contamination is hazardous or unacceptable • Separates acceptable lots from marginally acceptable lots between m and M limits n samples from the lot are tested all samples are ≤m accept lot ≤ c of n samples are within > m and ≤ M accept lot > c of n samples are within > m and ≤ M reject lot any sample is ≥ M reject lot Stringency is adjusted by changing the value(s) of c and/or n acceptable unacceptable acceptable marginally acceptable unacceptable Attributes Plans Two-class and Three-class