New compounds for iron fortification of foods

Iron deficiency is one of the most common nutritional problems in the world. PhD candidate at Utrecht University Neshat Moslehi, under the supervision of Willem Kegel and Krassimir Velikov, has designed compounds that could potentially be used for iron fortification of foods. This would be an efficient and cost-effective approach to overcome iron deficiency. The research, which was funded by NWO, took place in close collaboration with Wageningen University and Research, and Unilever Foods Innovation Centre. The invented compounds have recently been patented, and Moslehi will defend her thesis on Wednesday, 15 March 2023.

When visited at her office for an interview, Neshat Moslehi proudly presents her thesis. The cover immediately catches the eye: it shows a close-up picture of a sparkling rock. “It is photographed by my friend Joren Vos, and quite rare”, Moslehi says mysteriously. “It’s called Vivianite, a naturally-occurring multi-mineral containing iron, but also manganese, magnesium, and calcium. I knew it existed, but it took me a while to find it. Ultimately, I bought it from a mineral shop in Heerle.” However, it’s pretty appearance wasn’t by any means the only reason to make the rock the star of her PhD. In fact, it played an indispensable role in her research, because it was the source of inspiration from the very beginning.

Hiding iron

During her PhD, Moslehi’s goal was to design a compound which can be used to fortify food products with iron. Iron fortification of food is challenging, because iron tends to interact with the chemicals present in foods, leading to undesirable changes in, for example colour and flavour. The main idea of this project was to ‘hide’ iron by embedding it in a less reactive compound, to reduce iron reactivity in foods. And then reveal it once the food is consumed, so that the iron can be absorbed by the body. In her words: “We needed an iron-containing compound with minimum dissolution in the food-relevant pH, and maximum dissolution in gastric and intestinal pH.”

We all have heard of Popeye, the famous sailorman who boosts his strength by eating a can of spinach

Global health risk

Why go through all the trouble to fortify food with iron? When asked, Moslehi brings up the cartoon character Popeye. “Most of us have heard of him”, she says. “The famous sailorman who boosts his strength by eating a can of spinach. However, it would have been much more efficient for Popeye to knock back a can of meat. Both spinach and meat contain iron, but the non-heme iron in green leafy vegetables, beans, and nuts is much less absorbed in the body than the heme iron in meat.” The growing number of vegetarians and vegans on the one hand, and the lower meat consumption in developing countries on the other, have therefore resulted in iron deficiency being one of the biggest global health risks.

Innovative salts

Moslehi indeed succeeded in synthesizing such compounds. Inspired by natural minerals, such as the aforementioned Vivianite, she synthesized multi-mineral pyrophosphate-based salts, which contain iron and a second mineral such as calcium, zinc, or manganese that follows the necessary solubility balances. This means that an advantage of these compounds is the possibility to deliver of a second mineral, along iron at the same time.

After synthesizing, the salts were tested for their reactivity in the presence of selected phenolic compounds, such as quercetin, apigenin, and curcumin. These are present in citrus fruits, parsley, and turmeric. The results showed that the salts indeed reacted less with the compounds, because there were only limited changes in colour. In addition, tests in gastric-mimicked conditions were promising: they showed early indications that the iron would be effectively absorbed once it enters the body.

Actual invention

The salts were patented in early 2022. It’s a big family-patent, that Moslehi is really excited about: “By patenting it, these particles became an actual invention, which made my research one step closer to a sensible reality!”, she continues. “This doesn’t happen so often, at least not since I started working here.” It is exciting news, but we are not there yet: “Next steps would be to reproduce these compounds with food grade instead of lab grade chemicals, since the latter are not food approved. Also, we need to test the salts for their impact on characteristics of real food products, toxicity, and how well the body absorbs the iron, on a clinical scale.”

Flour, bread, soy sauce, and bouillon cubes

Should these particles indeed be suitable for iron fortification of foods, they would present an efficient and cheap approach to the global problem of iron deficiency. The preparation method of these salts is inexpensive and sustainable. Moslehi used a common technique (co-precipitation), which is green, cheap, fast, and easy, since it doesn’t require heating or usage of chemical solvents. Moreover, the designed salts can be added to products, such as flour, bread, soy sauce, or bouillon cubes. All in all, these innovative salts present a promising opportunity for introducing iron into our daily diet.