# Magnetic Properties of Commercial Cornflakes
## 4 Discussion  
It is not easy to determine the origin of the high concentration of Ba in the cornflakes, as determined by XRF, which is 32.8 mg/100 g. Using this spectrometry, we cannot determine the presence of anions, cations, or pure Ba in the cornflakes. Nevertheless, in this context, several scientific reports have analyzed the fatal toxic effects of Ba compounds [28; 29; 30]. Probably, the origin of this element in cornflakes could be associated with the cultivation process of corn, the nutrients in the soil, and the use of pesticides [31].  
On the other hand, according to the XRF and Table 1, the concentration of Fe was 7% lower than the content specified in the corresponding packaging. After analyzing the DIFs using XRD, no traces of any magnetic crystalline material other than iron were found. The type of iron crystals corresponds to a BCC structure, which is associated with \(\alpha\)-iron, and no crystals of any iron oxide were found.  
Using the FTIR spectra, the presence of iron oxides (crystal or amorphous materials) can also be discarded because of the absence of Fe-O bonds. Regarding our RBIFs, a significant fraction of alpha iron was probably oxidized during the first extraction procedure and subsequent storage. This would also explain the color differences between the DIFs and RBIFs. When the first extraction method was employed, the elemental iron was highly oxidized, resulting in the probable formation of hematite in RBIFs. This hypothesis is reinforced because the water solubilizes the content of NaCl and/or KCl, which work as electrolytes and promote the reaction of Equation (1) [32], on the surface of the metallic  
Figure 5: (**a**) Magneto-thermograms of both types of DIFs and pure iron samples, and (**b**) the corresponding derivatives of the relative magnetic forces.  
iron in the presence of O\({}_{2}\). Probably, the concentration of NaCl or KCl in the cornflakes analyzed in [17] was not sufficient to reach a fast oxidation of the iron extracted.  
\[4\text{Fe}+6\text{H}_{2}\text{O}+3\text{O}_{2}\to 4\text{Fe}(\text{OH})_{3} \to 2\text{Fe}_{2}\text{O}_{3}+6\text{H}_{2}\text{O} \tag{1}\]  
When the second method to extract the DIFs was applied, exhaustive washing of the iron filings in a controlled inert atmosphere allowed us to avoid oxidation of the iron and remove 99% of the organic and inorganic material attached to its surface. This is confirmed with the lack of resonances in the interval of 600 to 400 cm\({}^{-1}\) observed in the FTIR spectra [33]. Nevertheless, the RML and decomposition temperatures observed in the TGA measurements suggest the presence of 1% starch attached to the DIFs.  
The XRD and FTIR analyses using the respective reference samples suggest that the DIFs are composed principally of pure \(\alpha\)-iron. Additionally, the magnetic hysteresis loops confirm the ferromagnetic behavior with magnetic saturation very close to the reference sample of iron with 99.9% purity. For example, the magnetic saturation of the DIFs extracted from the brand 1 is 1% lower than that of the reference sample. Additionally, the Curie temperatures reached very close to 771 \({}^{\circ}\)C, together with the lack of other magnetic critical points associated with iron oxides, support this statement.  
It is crucial to discard the presence of ion oxides in fortified foods. For example, for decades, the cornflakes have been a leading source of fast food on the American continent. Millions of people, mainly children, eat breakfast of fortified cereal with milk every morning, unaware that the cereals contain a non-standardized type of iron, which must be widely studied for its interactions within the human body. It is well known that iron oxide particles can induce a high production of ROS in vitro experiments. It was observed using cell lines of the digestive tract, such as CACO-2 [34] or HT29 [35]. The ROS are directly related to apoptotic activity in cells, but uncontrolled oxidation can induce noxious effects on health.