Quality control materials in food composition databanks

Reference materials (RMs) have emerged with the aim of improving analytical methods performance, in what regards to their validation, calibration, uncertainty, training and internal quality control, and of increasing the comparability of measurements between laboratories. Due to their unquestionable importance, but still low availability and high cost, the present work has determined the suitability of infant formula, powdered garlic, tea and infusion as quality control materials for phosphorus analysis. Phosphorous was determined using a spectrometric method. Homogeneity and stability were determined within and between samples according with ISO guidelines. The results show that quality control materials prepared under rigorous procedures are valuable tools in the food composition analysis.