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