A proportionate stratified sampling scheme is used for the coordinated monitoring programme whereby the samples are allocated to every Member State proportionally to the size of the human population in that Member State.
the first level is composed of the major cities/towns to be sampled;
the second level is composed of the retail outlets to be sampled;
the third level is composed of the different food products within the three ready-to-eat food categories to be sampled.
the cities/towns included in the coordinated monitoring programme;
the types of retail outlets covered and the percentage of samples taken from each category;
the timing of the sampling throughout the year.
the types of products to be sampled within each of the three ready-to-eat food categories;
the number of samples to be taken from each type of product referred to in (a).
The competent authorities shall choose the retail outlets from which samples are to be taken. Typical types of retail outlets that shall be included for sampling are: supermarkets, small shops, speciality delis, and street markets (such as farmers’ or country markets).
If the biggest category of outlets (for example supermarkets) supply at least 80 % of the market of a ready-to-eat food category then samples only need to be taken from those outlets. Where that is not the case, the second largest outlet category shall be added until at least 80 % of the market is covered.
When sampling is performed according to a sampling plan, the number of samples that shall be taken for each category of ready-to-eat food from each retail outlet type shall be proportionate to the market share of that outlet type within the targeted outlet types.
The sampling shall take place in large cities/towns. At least two large cities/towns in each Member State must be sampled.
The cities/towns in which sampling is performed must, taken together, cover at least 30 % of the human population in the Member State. However, if the eight largest cities/towns are included in the plan, the human population coverage may be less than 30 %.
The contamination level of Listeria monocytogenes in ready-to-eat food may vary over the year. In order to ensure accurate results of the coordinated monitoring programme, its duration is divided in 12 periods of 1 month during which equal numbers of samples must be taken.
The ready-to-eat foods within the three ready-to-eat food categories to be sampled shall be selected based on the marketing data and detailed in the sampling plan.
The competent authorities may choose to instruct samplers to select cheeses for sampling based upon an estimated contribution to market share, according to the national sampling plan. The competent authorities should also provide some direction on approximate market share of major types of food within categories to best approach a sample representative of market, e.g. raw/pasteurised milk cheeses.