Fish Microbiology and Quality Assurance

Unit 9 - Assurance and management quality of fish

9.1.5. Statistical methods
Assessing the quality of the product involves drawing representative samples for analysis and decision making. For this purpose statistical principles are to be followed which help in sampling correct number, size and kind of samples for analysis as it is not possible to examine every item in a batch of product. Further, making decision as to whether to accept or reject a batch or to place a batch in a particular grade is determined by following statistical principles.

End product inspection of fish products uses the practices of acceptance sampling by attributes. A sample of 'n' items is taken from the lot and tested according to the product specification. After examination, each item is declared as having passed or failed. The lot is accepted if 'c' (maximum acceptable number) or fewer items in the sample fail. The sampling plan generally specifies values of 'n' and 'c'.