# Modification of Mineral Content in Bread with the Addition of Buckwheat Husk
## 3 Results and Discussion  
### Mineral Contents in the Tested Bread Samples  
The results showed that potassium and phosphorus were the most abundant minerals in both the enriched and non-enriched breads (Figure 1a,b). Their contents ranged, depending on the addition of buckwheat husk, from 175.3 to 197.2 mg/100 g and from 122.4 to 129.7 mg/100 g in toasted bread, while in wholemeal bread, they ranged from 253.0 to 266.6 mg/100 g and from 212.0 to 209.6 mg/100 g, respectively. Copper and manganese were found in the lowest amounts ranging from 0.10 to 0.12 mg/100 g and from 0.56 to 0.79 mg/100 g in toasted bread and from 0.19 to 0.21 mg/100 g and from 1.39 to 1.55 mg/100 g in wholemeal bread (Figure 1c,d), respectively. The calcium content in both types of analyzed breads ranged from approx. 67 to 88 mg/100 g (Figure 1e), while the sodium and magnesium levels (Figure 1f,g) were several times lower and ranged from approx. 20 to 59 mg/100 g. The iron and zinc contents were detected in significantly lower amounts, from approximately 1 to 2.5 mg/100 g (Figure 1h,i). Similar contents of mineral components, especially a high level of potassium and phosphorus and low amounts of copper and manganese in various types of breads, were indicated by [PERSON] et al. [18] and [PERSON] et al. [19]. Their studies confirmed that the levels of minerals in bread depend not only on the type of grain from which the flour was obtained but also on the method applied for grain milling, the flour extract, and other ingredients used in the baking process. In our study, for almost all elements that were tested, the quantities present in the wholemeal breads were superior to the quantities measured in the toasted breads with and without the addition of buckwheat husk. Wholemeal bread without buckwheat husk contained higher levels of chromium (Cu), manganese (Mn), iron (Fe), zinc (Zn), magnesium (Mg), and potassium (K) in comparison with nonenriched toasted bread. This is largely due to the retention of the bran and germ, which are naturally rich in minerals in wholemeal flour during its processing. In comparison with wholemeal flour, white wheat flour (used in toasted bread preparation) undergoes milling processes that remove these nutrient-dense components. Analyzing the effect of husk addition on the levels of elements determined in the toasted bread showed that it caused a systematic increase in the levels of potassium, manganese, zinc, and magnesium (Figure 1a,d,g,i). The potassium content increased from the level of 175.3 mg/100 g in the control sample to 197.2 mg/100 g in the sample with the highest, 4.5%, husk addition; the manganese, zinc, and magnesium contents increased from 0.56 to 0.79 mg/100 g, from 0.96 to 1.12 mg/100 g, and from 20.9 to 24.0 mg/100 g, respectively (Figure 1a,d,g,i). The addition of 3% and 4.5% husk also caused an increase in the sodium content, while the lowest addition of husk resulted in a decrease in this element's level (Figure 1f). The calcium level was significantly (\(p<0.05\)) affected by husk addition at all levels of enrichment, increasing from 67.6 mg/100 g in the control sample to the highest content of 87.7 mg/100 g in TB 3.0% (Figure 1e). On the contrary, the addition of buckwheat husk did not significantly increase (\(p<0.05\)) the copper and phosphorus levels, which were slightly reduced by the 1.5% husk addition (Figure 1c,b). Also, no significant (\(p<0.05\)) difference in the content of iron was observed after husk addition in the tested toasted breads (Figure 1h). Figure 1: Effects of different buckwheat hull additions on individual mineral contents in toasted and wholemeal breads. Values are expressed as means (n = 3) \(\pm\) standard deviations. Mean values for the individual mineral contents of tested toasted and wholemeal breads with different lowercase letters  
are statistically different (_p_ < 0.05) according to the Duncan's test.