Concentrations of macro and microelement in Brazilian white cheeses: Evaluating sample preparation procedures and estimation of dietary intake.

Two sample preparation procedures, microwave-assisted and closed digestion block, were developed to establish the nutritional content of white cheeses. A two-level full factorial design was performed to optimize the decomposition parameters. Under optimum conditions, both procedures led to low dissolved carbon content (< 11% w.w-1) employing 2 mol. L-1 HNO 3. Nevertheless, the closed block presented smaller analytical throughput with approximately 11 digested samples h-1 against 20 samples h-1 for MW. Both procedures showed accuracy for Ca, K, P, Na, and Zn and precision with RSD < 10%. The limits of detection ranged from 2.2 (P) to 16 μg g-1 (Ca) (microwave) and 0.8 (K) to 14 μg g-1 (Na) (closed block). The validated procedures were employed to analyze buffalo mozzarella, minas frescal, Ricotta, Coalho, and cottage cheeses. Based on the nutritional analysis, the type of cheese influenced the variation in nutrient content. Furthermore, for all types of cheese, a discrepancy (p < 0.05) was observed between concentrations for at least one analyte, confirming the lack of uniformity in nutritional composition. The recommended daily intake evaluation demonstrated that all samples of buffalo mozzarella and minas frescal cheese analyzed could be considered sources of Ca and P. [Display omitted] • Two closed-vessel digestion procedures using diluted HNO 3 were developed for five white cheeses. • A closed digestion block with diluted acid was evaluated for the first time for protein food samples. • Low-fat cheeses were analyzed for nutrient elements Ca, K, P, Na, and Zn determination. • Buffalo mozzarella and minas frescal are sources of Ca and P with > 15% of the RDI per 30 g of cheese. [ABSTRACT FROM AUTHOR]