Changes in mineral and protein content of wheat flour due to fertilizers

Monday, March 24, 2014

Authors: Zita Kata Burján, Dávid András1, Zoltán Gy




In this study the effect of different NPK doses on the contents of K, P, S, Mg, Ca, Fe, Mn, Zn, Cu, Sr and protein were investigated in the flour of winter wheat. Samples were collected from Nagyhörcsök which is one of the experimental stations of the Hungarian National Long-term Fertilization Trials. The elements content of samples were measured using inductively coupled plasma optical emission spectrometer followed by digestion with HNO3-H2O2 solution. The protein content was determined using Khjeldal method.

The statistical analysis of the effect of NPK treatments was made using statistical method of independent samples T-test. It was proved that N treatments caused significant difference in the amount of Ca, Cu and Sr (P<0,05) and there were strong significant correlation between N fertilizer and S, Mn and protein content of flours. The superphosphat had strong positive significant effect (P<0,01) on the P, Mn, and Sr content and positive significant effect (P<0,05) on the Sr concentration but strong negative significant influence (P<0,01) on the amount of Zn and Cu in the flour. K fertilization reduced the accumulation of Ca and Sr.




The fruits of cereal crops are important sources of minerals and nutrients for humans (McKevith, 2004). However, distribution of mineral elements in wheat grain is uneven. Most of them are contained in the aleurone layer (Shi, 2010), but in many countries it is the endosperm, lowest in mineral components, that is consumed the most (Kutman, 2011). At the samoe time, insufficient mineral intake is a growimg problem in human nutrition (White and Broadley, 2005).


It is an important requirement for wheat berry to have as high protein content as possible. The reason for this is that protein content has a beneficial effect on the baking quality of wheat flour, and also the digestability of the bread made of it (Loch, 1999). Protein can be found in all parts of wheat grains, but the highest concentrations are in the aleurone layer and the germ, so the whole grain is more valuable than products made of the endosperm – even in terms of protein content (Lásztity, 1981). Taking into consideration that application of fertilizers is one of the most important, most critical factors in the production technology of fall wheat (Pepó, 2004), the aim of our research was to answer the question whether it is possible to increase the element and protein content of wheat flour by the use of suitable configured nitrogen and NPK fertilizing strategies, and to find out how different levels of NPK treatments influence the element content of wheat flour.

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