Application Note – Food N.1 – Sampling Plan according Codex Alimentarius
Sampling Plan according Codex Alimentarius
Codex Methods of Sampling are designed to ensure that fair and valid sampling procedures are used when food is being tested for compliance with a particular Codex commodity standard.
The sampIing methods are intended for use as international methods designed to avoid or remove difficulties which may be created by diverging legal, administrative and technical approaches to sampling and by diverging interpretation of results of analysis in relation to lots or consignments of foods, in the light of the relevant provision(s) of the applicable Codex standard.
Type of Sampling Plans and Procedures
(a) Sampling Plans for Commodity Defects:
These are normally applied to visual defects (e.g. loss of colour, mis-graded for size, etc.) and extraneous matter. They will normally be attribute plans, and plans such as those included in CAC/R1M 42-1969 may be applied.
(b) SampIing Plans for Net Contents:
These are sampling plans which apply to prepackaged foods generally and are intended to serve to check compliance of lots or consignments with provisions for net contents.
(c) Sampling Plans for Compositional Criteria:
Such plans are normally applied to analytically determined compositional criteria (e.g., loss on drying in white sugar, etc.). They are predominantly based on variable procedures with unknown standard deviation.
(d) Specific Sampling Plans for Health-related Properties:
Such plans are generally applied to heterogeneous conditions, e.g., in the assessment of microbiological spoilage, microbial by-products or sporadically occuring chemical contaminants.
General Instructions for the Selection of Methods of Sampling
(a) Official methods of sampling as elaborated by international organisations occupying themselves with a food or a group of foods are preferred. Such methods, when attracted to Codex standards, may be revised using Codex recommended sampling terms (to be elaborated).
(i) the basis on which the criteria in the Codex Commodity standards have been drawn up (e.g. whether on the basis that every item a lot, or a specified high proportion, shall comply with the provision in the standard or whether the average of a set of samples extracted from a lot must comply and, if so, whether a minimum or maximum tolerance, as appropriate, is to be given);
(ii) whether there is to be any differentiation in the relative importance of the criteria in the standards and, if so, what is the appropriate statistical parameter each criterion should attract, and hence, the basis for judgement when a lot is in conformity with a standard.
(b) Instructions on the procedure for the taking of samples should indicate the following:
(i) the measures necessary in order to ensure that the sample taken is representative of the consignment or of the lot;
(ii) the size and the number of individual items forming the sample taken from the lot or consignment;
(iii) the administrative measures for taking and handling the sample.
(c) The sampling protocol may include the following information:
(i) the statistical criteria to be used for acceptance or rejection of the lot on the basis of the sample;
(ii) the procedures to be adopted in cases of dispute.
Selection of Specific Sampling Procedures which are in EC Legislation and Guidelines
- PRESERVATIVES
- CASEIN AND CASEINATES
- PRESERVED MILK PRODUCTS
- PESTICIDES
- NITRATES
- AFLATOXINS (UK)
Types of Codex Sampling Plans
TYPE OF CHARACTERISTIC
3.1 Commodity defects (e.g. as applied to visual defects such as loss of colour, mid-grading, extraneous matter etc.)
3.2 Compositional characteristics: these may be normally distributed (e. g. most analytically determined compositional characteristics such as loss on drying in white sugar) or they may be non-normally distributed (e.g. analytically determined compositional characteristics in some commodities).
3.3 Net contents (as applied to prepackaged foods).
3.4 Health-related properties (e.g. in the assessment of microbiological spoilage, microbial hazards, sporadically occurring chemical contaminants etc.).
TYPE OF SAMPLING PLAN
“Attribute” (e.g. as in Codex Sampling Plans for Pre-packaged Foods, CAC/RM 42-1969)
“Variables with unknown standard deviation” for normally distributed characteristics and “attribute” for characteristics whose distributions deviate significantly from normal.
Sampling plan to be in agreement with the recommendations included in Section 7.
Specified sampling plans to be propose appropriate to each individual situation (e.g. the IDF 113 and the ICMSF Standards). Plans to detect incidence rates in a population may be used.
References
Roger Wood, Food Labelling & Standard Division, MAFF – Survey of EC and Codex Regulations and Directives. Sampling for Food Analysis Training Course – Nov 27, 1996 – FOOD RA – Leatherhead – UK.
