Sampling

The analysis was performed on samples of food purchased by the participants in supermarkets or other usual points of sale listed. All samples were stored following the recommendations found on their labels and the ready-to-eat takeaway products were stored in the refrigerator and frozen as quickly as possible. If certain sub-samples required any kind of preparation or cooking, they were processed strictly following the manufacturers’ instructions, by usual domestic practices.

For each product, five samples from three different batches were purchased. To allow for thorough homogenization of samples and to obtain representative aliquots 26 of the products analyzed, five samples from the same batch were homogenized to obtain a composite sample. The same was done for the other two batches purchased. Three composite samples (each with 15 sub-samples) were formed and prepared for TFA analysis. A total of 42 samples were analyzed.