Effect of Processing on Some Quality Parameters of Flour and Bread Made from Wheat Grain Biofortified with Zn and Se

Abstract

Millions of people have inadequate Se and Zn intakes, but agronomic biofortification could prevent this. This study evaluated the effect of the combined Zn and Se biofortification on the quality parameters of grain, and on the composition of minerals (Zn, Se, Mg, Ca and Fe) and their availability in bread-making wheat (Triticum aestivum L.) products, white flour, wholemeal bread and white bread were evaluated. The studied treatments were soil Zn (no Zn, and 50 kg Zn ha−1) and foliar applications (0, 10 g Se ha−1, 8 kg Zn ha−1, and 10 g Se ha−1 + 8 kg Zn ha−1) and were tested in a two-year field experiment (2017–2018, 2018–2019). The foliar combined biofortification increased the concentration of both minerals in white flour, wholemeal bread and white bread by about 33%, 24% and 51%, respectively for Zn, and 3.3-fold, 3.4-fold and 2.7-fold for Se, showing a synergistic effect on Se concentration with the Se and Zn combination. While the loss of Zn and Se during the milling process was41% and 18%, respectively, baking caused a loss of 15% and 19%, respectively, for wholemeal bread, and up to 61% and 29% for Zn and Se for white bread. Hence, although the consumption of wholemeal bread instead of white bread may enhance Zn and Se intake more than biofortification, until consumption habits change, the biofortification of wheat can help to mitigate inadequate Zn and Se intakes in the general population.

Keywords

• sodium selenate
• zinc sulfate
• cereal
• rainfed conditions
• bread