. 2022 Jun 10;7(24):20441–20456. doi: 10.1021/acsomega.2c01833

Table 3. Recent in Vitro Studies on Improving Iron Bioavailability.

technique	compound	food	results	reference
encapsulation	iron encapsulated in thermo-resistant modified starch with or without vitamin C	conventionally and sourdough fermented breads	The bioavailability and bioaccessibility of iron from conventially fermented bread were higher in general.	(136)
			Iron transport efficiency represented a wide range (1.16–13.78%).
			Fortified breads showed bioaccessibility values changing from 41.45 to 99.31%.
			Type of fermentation affected the degree of iron oxidation during digestion.
			Iron source, either ferrous sulfate or ferrous lactate, showed an effect on tested parameters but not statistically significant.
	microencapsulated iron coated by whey protein isolate and a starch-based aqueous coating	tea	Cellular absorption or iron from microcapsules was increased by 73%.	(140)
		tea	Within 30 min of tea brewing, microcapsules reduced the formation of the iron–polyphenol complex in the tea by 60%.	(140)
chelation	iron–casein complex with ascorbic acid	water and milk	Ascorbic acid addition at the molar ratio of 2:1 improved the iron absorption from ICCs and FeSO₄ to close levels, and absorption levels were significantly higher than ferric pyrophosphate (FePP) with and without ascorbic acid.	(153)
	lentil-derived hydrolyzed protein–iron complex	-	A significant decrease in the anemic condition in caco-2 cells was observed by looking at the mRNA levels of marker genes (divalent metal transporter-1 (DMT1), transferrin receptor (TFR), and ankyrin repeat domain 37 (ANKRD37)) that were induced by iron deficiency anemia.	(157)
	iron–red tilapia viscera hydrolysate complex	-	The highest iron binding ability was obtained by hydrolysate with 42.5% of hydrolyzation degree.	(158)
	iron–red tilapia viscera hydrolysate complex	-	4.7 times higher bioavailability compared to free iron salts was obtained in the complex of red tilapia viscera hydrolysate with 42.5% of hydrolyzation degree and iron.	(158)
	whey protein–iron complex	-	Both mineral uptake and ferritin synthesis were better in the case of WP–mineral complexes.	(160)
	whey protein–iron complex	-	Minerals (iron and zinc) complexed with whey protein showed a significantly lower pro-oxidant activity but had higher bioaccessibility (76%) compared to iron salts alone (68%).	(160)
	whey protein–iron FeCl₂ and FeSO₄) complex	-	Complexes prepared with low molecular mass peptides and FeCl₂ enhanced the iron bioavailability by approximately 70% compared to FeSO₄.	(159)
	whey protein–iron FeCl₂ and FeSO₄) complex	-	Complexes except for those synthesized with low molecular mass peptides (<5 kDa) increased bioaccessibility value to a level higher than 85%.	(159)