Produção de material de referência para o escopo umidade, cinzas, gordura total e acidez titulável em leite em pó integral

Abstract

Considering the importance of the reference materials (RM) in the structuring and maintenance of quality management systems for food analysis laboratories, representing a fundamental tool to ensure the reliability and traceability of analytical results, RM were experimentally produced for the scope moisture, ash, total fat and titratable acidity in whole milk powder bovine. Two types of packaging (sachets stand-up pouch metallized polyethylene terephthalate / low density polyethylene and amber glass bottles with a screw cap) and three storage temperatures (ambient, refrigeration and freezing) were evaluated. The batches produced were homogeneous. The materials packed in sachets, evaluated at different temperatures, and materials packaged in amber glass bottles, stored at room temperature showed no stability for the parameter moisture. However, for the parameters ash, total fat and titratable acidity, all materials were considered stable for six months. The tests of homogeneity and stability were conducted in accordance with the protocol harmonized by International Union of Pure and Applied Chemistry, ISO Guide 35 and ISO 13528, with concordance between the results, despite the different criteria. The contribution of variances due to the homogeneity and stability were estimated for the materials certification.