A case study on minerals accumulation in grains and flours of bread wheat fertilized with ZnSO₄ and Tecnifol Zinc

Nowadays there is an increasing demand for foods capable of fulfilling the nutritional needs of consumers, leading to a search for food products with a nutrient content able to promote a healthier lifestyle. In this study an agronomic biofortification itinerary of Triticum aestivum L. (cv. Paiva) was conducted in an experimental field, located in Beja, Portugal, comprising a foliar fertilization with ZnSO₄ and with Tecnifol Zinc, in three different concentrations for each fertilizer, along the plant cycle. A mineral quantification (S, K, Ca and Zn) of whole bread wheat flours and refined bread wheat flours was measured by using a XRF analyzer, whereas the µ-EDXRF was used to quantify the minerals within the different regions of the wheat grain (embryo, endosperm and vascular bundle). All the minerals presented lower values in the refined flour relatively to the whole bread wheat flour, in which K had higher values followed by S and finally Ca with the lower values in both types of flours. The different minerals were spread around the various regions of the grain however, they were more concentrated in the embryo and vascular bundle. The values are similar for both fertilizers, with a slight difference regarding Zn values, namely increasing with ZnSO₄. To sum up, as the different minerals tend to accumulate in the embryo and vascular bundle, the whole bread wheat flour presents a richest option, promoting a healthier diet for the consumers.