Enhancing mineral bioavailability from cereals: Current strategies and future perspectives

Abstract

Inadequate intake of essential minerals such as iron and zinc is a public health concern in the UK, particularly for girls and young women. Approximately 30% and 50% of the zinc and iron, respectively, in the UK diet is provided by cereals. In wheat, most of the iron and zinc is contained within the aleurone cell layer; however, aleurone is removed during processing of wheat into white flour. While elemental iron powder is added back into white flour at the milling stage, there is no restoration of zinc. Elemental iron powder has very low bioavailability, and therefore, in our current Biotechnology and Biological Sciences Research Council Diet and Health Research Industry Club-funded project, we are investigating the potential use of aleurone as a bioavailable source of minerals that could be added to wheat-based foods. This work has relevance for the food industry and may establish the use of aleurone as a functional food ingredient for fortification of a range of cereal-based food products.

Keywords: aleurone; bioaccessibility; bioavailability; iron; wheat; zinc.

Figure 1

Structure of the wheat (Triticum aestivum) caryopsis. (a) The structure of the mature wheat grain. (b) The position of the aleurone layer relative to the testa and pericarp, and the starchy endosperm. Graphics are taken from The Seed Biology Place (http://seedbiology.de) and are reproduced with the kind permission of Professor Gerhard Leubner, Royal Holloway, University of London.