Mineral and trace elements in nutritious flours: total contents, in vitro bioaccessibility and its contribution to dietary intake

The consumption of fruits, vegetables and cereals in the form of flour has been an alternative for the intake of nutrients, currently seen in society that seeks a healthier diet. Thus, the assessment of total content and bioaccessibility is important to better understand the actual intake of nutrients or contaminants present in foods. The aim of this study was to determine the total content and estimate the bioaccessible fraction of Cu, Fe, and Zn in nutritious flours by inductively coupled plasma optical emission spectrometry (ICP OES) after microwave acid digestion. Bioaccessibility was assessed using in vitro method that takes into account the entire gastrointestinal tract (Unified Bioaccessibility Method (UBM)). The following concentration ranges, in μg g -1 , were found: Ca (341 - 6275), K (2984 - 13953), P (476 - 6110), Na (<0.39 - 2995), Fe (1.4 - 167), Cu (<0.01 - 59.6) and Zn (<0.07 - 30.3). Application of principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed a tendency to form three groups. The bioaccessible fractions for Cu, Fe and Zn were considered low, ranging from 0.96 to 40% in the gastrointestinal phase and from 4.1 to 100 % in the gastric phase.