Comparison of the Availability of Various Iron Fortificants in Bread and Milk Using an In Vitro Digestion/Caco-2 Cell Culture Method

ABSTRACT: The availabilities and dialyzabilities of various iron fortificants in bread and milk were compared using an in vitro digestion/Caco-2 cell culture model. In white bread, availability and dialyzability of electrolytic iron were lower than that of ferrous fumarate, Ferrochel®, and FeSO₄. NaFe(III)EDTA was also lower in availability than ferrous fumarate, Ferrochel®, and FeSO₄ but had the highest dialyzability. In 2% fat milk, NaFe(III)EDTA was again the highest in dialyzability but was similar in availability to ferrous fumarate, encapsulated ferrous fumarate, Ferrochel®, and FeSO₄. The results suggest that iron from NaFe(III)EDTA and electrolytic iron does not completely exchange with intrinsic iron in foods.     

Bioavailability of Elemental Iron Powders in Bread Assessed with an In vitro Digestion/Caco-2 Cell Culture Model

ABSTRACT: Iron fortification of staple foods is arguably the most widely used strategy for increasing the iron intake of populations. Although FeSO₄ is a bioavailable form of iron, elemental iron powders are often used to fortify products with a long shelf-life, such as wheat flours, to avoid problems associated with the reactive nature of FeSO₄. Therefore, the objectives of this study were to compare the bioavailabilities of elemental iron powders manufactured with different production methods in wheat flour breads and to determine the effects of added ascorbic acid and baking, using an in vitro digestion/Caco-2 cell culture model. Two types of wheat flour (low-extraction and high-extraction) were fortified with 10 different commercial elemental iron powders and baked into breads. Iron bioavailabilities from the resulting breads, with and without added ascorbic acid, were evaluated using FeSO₄ as the control. Depending on the type of wheat flour, bioavailabilities of several powders were comparable to FeSO₄, but there was no consistent trend as to which production method produced the most bioavailable powder. In general, ascorbic acid enhanced, whereas the baking process reduced iron bioavailability from bread. Our results suggest that some elemental iron powders are potential alternatives to FeSO₄. Human studies are warranted before any of these powders are selected for national fortification programs.     

Sensory Trial to Assess the Acceptability of Zinc Fortificants Added to Iron-fortified Wheat Products

ABSTRACT: We studied the sensory acceptability of products made from iron- and zinc-fortified wheat flour. Subjects tasted bread and noodles fortified with 30 mg of iron as FeSO₄/kg flour or iron and either 60 or 100 mg of zinc/ kg flour as either ZnSO₄ or ZnO. Subjects rated their degree of liking (DOL) for flavor, texture, and overall acceptability, using a 9-point hedonic scale. All products were generally well liked, although noodles fortified with iron and ZnO had slightly lower DOL scores than noodles fortified with iron only or iron and ZnSO₄. We conclude that foods prepared from zinc-fortified wheat flour should be well accepted.     

Effects of Iron Source on Iron Availability from Casein and Casein Phosphopeptides

ABSTRACT: :
Iron availability from FeSO₄ in samples containing sodium caseinate (SC), casein phosphopeptides (CPP) or whey protein concentrate (WPC), and from ferric citrate (Fe-CA) in samples containing SC or CPP was measured using an in vitro digestion/Caco-2 cell culture model. In FeSO₄ spiked samples, relative availability was CPP > SC, CPP = WPC, and CPP = FeSO₄ alone. In samples containing Fe-CA, a soluble iron chelate, relative availability was CPP = SC and CPP < Fe-CA alone. These results suggest that CPP enhances iron availability from foods with low availability but does not improve and may inhibit availability from soluble iron species.     

Iron Bioavailability from Common Raisin-containing Foods Assessed with an In Vitro Digestion/Caco-2 Cell Culture Model: Effects of Raisins

The effects of raisins on iron bioavailability from wheat bran cereal, bread, rice pudding, and granola bars were studied. Iron bioavailability was assessed with an in vitro digestion/Caco‐2 cell culture model. Raisins reduced iron bioavailability from all foods except granola bars. Raisins also reduced iron bioavailability from samples of wheat bran cereal and bread fortified with elemental iron or ferrous sulfate, but this inhibitory effect was less pronounced in samples fortified with sodium iron ethylenediaminetetraacetate (NaFeEDTA). Iron bioavailability was markedly higher for samples fortified with NaFeEDTA, suggesting that iron in the form of NaFeEDTA is more bioavailable than elemental iron or ferrous sulfate in raisin‐containing foods.     

Fortification of soy sauce using various iron sources: sensory acceptability and shelf stability

BACKGROUND: Soy sauces are available in different types and grades, which allows them to reach consumers of all socioeconomic groups. Ferric sodium ethylenediaminetetraacetic acid (NaFeEDTA) has been used for iron fortification of soy sauces in some countries, however, its high cost may make it unattractive to policymakers and industry. OBJECTIVE: We evaluated the feasibility of using more economical iron sources for iron fortification, with soy sauce of various types and grades used as a vehicle. METHODS: Seven iron sources were tested for their feasibility for fortification of four types of soy sauce: naturally fermented in the traditional style, naturally fermented according to large-scale industrial formulas 1 and 5, and chemically hydrolyzed at 5 mg per serving (15 mL, per Thailand's food labeling regulations). Either citric acid or sodium citrate was added at 0.1% as a chelator. RESULTS: Five iron sources--ferrous sulfate, NaFeEDTA, ferric ammonium citrate, ferrous lactate, and ferrous gluconate--did not significantly affect the sensory qualities of the product over a period of 3 months (p > .05). Ferrous fumarate and ferrous bisglycinate caused unacceptable precipitation. Less than 3% of 260 and 306 commonly cooked foods out of 871 and 772 preparations using soy sauces fortified with NaFeEDTA and ferrous sulfate, respectively, were found to be different from normal with regard to sensory qualities. The cost of fortification was US 0.22 cents to US 3.28 cents per bottle (700 mL). CONCLUSIONS: Both naturally fermented and chemically hydrolyzed soy sauces could be fortified with all five iron sources. Ferrous sulfate is the most appropriate source because of its low cost and acceptable sensory characteristics. Soy sauce is a promising vehicle for iron fortification, however, the bioavailability of iron in the products examined here needs to be evaluated under normal use conditions.     

Development and Evaluation of Iron-fortified Extruded Rice Grains

ABSTRACT: Although rice can be fortified with iron by producing fortified extruded grains, achieving good sensory properties and high iron bioavailability is difficult. Our study aim was to develop iron-fortified rice with comparable sensory characteristics to natural rice using iron compounds of high bioavailability. We tested ferrous sulfate, NaFeEDTA, ferric pyrophosphate of different particle sizes (mean particle sizes: 20 (j,m, 2.5 μm, 0.5 μ-m) and electrolytic iron, as well as encapsulated forms of iron. Extruded rice grains containing 0.5 and 1 g Fe/ 100 g were produced using a single screw extruder and blended, respectively, with natural rice at a 1:100 or 1:200 ratio. Extruded rice grains were evaluated by color measurements and texture profile analysis, and iron loss during rinsing was measured. The sensory comparison between fortified and unfortified rice was performed using triangle tests. Color scores in a similar range to natural rice were obtained using ferric pyrophosphate as an iron fortification compound. The cooked extruded grains had comparable texture to cooked natural grains, and losses during rinsing were <3%. Fortification with all other compounds resulted in strong color changes. In the triangle tests, rice grains fortified with either of the 2 forms of micronized ferric pyrophosphate closely resembled unfortified rice in both uncooked and cooked form. Iron-fortified extruded rice grains with excellent sensory characteristics and potential high bioavailability can be produced using micronized ferric pyrophosphate.     

Effect of Iron on the Color of Barley and Other Cereal Porridges

ABSTRACT: Iron added as ferrous sulfate at 500 mg*kg⁻¹ to rice, oats, whole grain wheat, or proanthocyanidin-free barley porridge caused significant changes in the Hunter "L", "a", and "b" values but the visual appearance of these porridges remained satisfactory. Porridge made with normal barley flour fortified with 500 mg*kg⁻¹ of iron developed an unappealing gray color with ferrous sulfate, ferrous fumarate, or electrolytic iron, 3 salts differing in solubility. At 100 and 250 mg*kg⁻¹ of iron, the discoloration of normal barley porridge was less pronounced, but still objectionable. When fortified with 50 mg*kg⁻¹ of iron, normal barley porridge had a slight color change but was not noticeably gray. Thus barley-containing foods can be fortified with a soluble iron compound at the level of iron used in enriched flour and similar cereal-grain foods for the general population without developing an unattractive color.     

A rapid method for iron determination in fortified foods

The objective of this study was to develop and evaluate a rapid method for iron determination in fortified and unfortified foods. Method: samples were mixed with an iron-extracting solution (1.2 M HCl, 0.6 M trichloroacetic acid, and 0.7 M hydroxylamine hydrochloride) and heated in a boiling water bath for 15 min. The mixtures were cooled and filtered. The filtrate was mixed with a chromogen reagent (0.03% bathophenanthroline disulfonic acid in 3 M sodium acetate). Iron concentration was determined by measuring absorbance at 535 nm. The accuracy of the rapid method was validated by comparing results to a standard laboratory method for iron determination. Results: the rapid method produced accurate results for the majority of the food samples tested, including wheat flour fortified with FeSO₄, electrolytic iron, NaFeEDTA, Ferrochel® or ferrous fumarate; powdered drink mixes, and enriched rice. However, results obtained using the rapid method were significantly lower than results obtained using the standard method for the enriched cornmeal (30.04 vs. 33.16 μg Fe/g; P=0.0118) and the enriched flour (41.90 vs. 47.28 μg Fe/g; P<0.0001). Conclusion: The rapid method is simple, inexpensive, and suitable for monitoring iron concentrations in fortified foods.     

Acceptability of complementary foods and breads prepared from zinc-fortified cereal flours among young children and adults in Senegal

We completed a series of studies to assess the acceptability of zinc-fortified, cereal-based complementary foods and zinc-fortified wheat breads. Young children and their caregivers completed acceptability tests with complementary foods fortified with iron only (60 mg iron as ferrous fumarate per kilogram cereal flour), or the same level of iron and zinc (240 mg zinc as zinc oxide per kilogram cereal flour), and the caregivers completed triangle taste tests to compare the same products. A separate group of adult participants completed acceptability tests with wheat breads fortified with iron and folic acid (15 mg iron as ferrous fumarate per kilogram flour and 1.5 mg folic acid per kilogram flour) or the same levels of iron-folic acid and 2 levels of zinc (63 mg zinc or 126 mg zinc as zinc oxide per kilogram flour). Finally, a threshold test was administered to another group of adult participants to compare nonfortified wheat bread to breads fortified with zinc in 80 mg increments ranging from 80 to 400 mg zinc as zinc oxide per kilogram flour. All products were acceptable when compared to non-zinc-fortified equivalents, and were well liked by the respective participants. For the triangle tests, caregivers were not able to detect significant differences between products. For threshold tests, adult participants detected differences in breads prepared from fortified wheat flour at 80 mg, 160 mg, and 320 mg zinc per kilogram flour, but not at 240 mg and 400 mg zinc per kilogram flour, respectively, when compared to nonfortified bread equivalents. Zinc fortification of cereal flours in the ranges of fortification that were tested does not adversely affect the acceptability of complementary foods and breads prepared from these flours. Practical Application: Fortification of staple food products is a low-cost approach to deliver additional micronutrients (including zinc) to large segments of a population. Determining the acceptability of products fortified with zinc is an important step in the development of zinc fortification programs.     

Development of fortified biscuit using NaFeEDTA

BACKGROUND: Sodium iron ethylenediaminetetraacetic acetate (NaFeEDTA) is a promising iron fortificant for populations consuming high‐phytate diets. It produces fewer organoleptic effects than other fortificants do, especially when the matrix of the food vehicle contains fat, and has a bioavailability two to four times higher than that of ferrous sulfate. This study investigated the effects of varying levels of NaFeEDTA (576–1152 mg kg^?1) on the physicochemical and sensory characteristics of Petit Beurre biscuits. RESULTS: There were no significant differences in pH, ash, moisture and breaking strength values among all formulae. The iron content (7.2–14.4 mg per 100 g) of the biscuits increased with increasing fortificant level. During a 60 day storage period the peroxide value increased in both fortified and non‐fortified formulae, especially after 28 days. The addition of NaFeEDTA had a significant (P < 0.05) effect on the colour, texture and flavour of fortified biscuits. CONCLUSION: Based on the range proposed for the use of NaFeEDTA as a fortification agent (10 mg iron and 67 mg EDTA per person per day), the results of this study reveal that 720 mg kg^?1 NaFeEDTA (9 mg iron per 100 g) is the optimum level for iron fortification in Petit Beurre biscuits. Copyright © 2011 Society of Chemical Industry     

Iron‐encapsulated cold‐set whey protein isolate gel powder ‐ Part 2: Effect of iron fortification on sensory and storage qualities of Yoghurt

Iron was incorporated at 20–60 mg/kg of yoghurt using iron‐encapsulated cold‐set whey protein isolate gel powder (WPI‐Fe) and by direct addition of ferrous sulphate solution. The changes in physicochemical and sensory qualities of the yoghurt samples were determined over 14 days of storage. Quality attributes of the yoghurt fortified using WPI‐Fe particles at up to 60 mg iron/kg were similar to those of unfortified control samples, especially in terms of colour and flavour, while the samples fortified by direct addition of ferrous sulphate exhibited noticeable adverse effects even at 20 mg iron/kg.     

Iron fortification of skim milk: Minerals and 57Fe Mössbauer study

Reconstituted skim milk was fortified at 2, 5, 10 and 20 mmol Fe kg^?1 with ferric and ferrous chloride iron with or without reversible acidification by injection of CO₂ under pressure. Carbonation improved transfer of iron from the soluble to the colloidal phase and accelerated ferrous iron oxidation. ⁵⁷Fe Mössbauer spectra of the freeze-dried casein micelles collected by centrifugation demonstrated that iron is present in a distorted octahedral coordination and is chelated by phosphate rather than citrate. Milk iron fortification induced several changes in the mineral component of the casein micelles, which are explained by the formation of a ternary complex: inorganic phosphate–iron–organic phosphate.     

2种铁营养强化剂对强化酱油感官影响的比较

该实验分别用乙二胺四乙酸铁钠(NaFeEDTA)和硫酸亚铁(FeSO4)与柠檬酸的混合物对低盐固态发酵酱油(虎王酱油)和高盐稀态发酵酱油(宽牌酱油)进行强化，强化剂量均为5mg铁／15mL酱油。室温静置ld后，对强化后酱油的色泽、香气、味道、体态、金属味等指标进行评价。结果表明，2种不同生产工艺的强化酱油中，NaFeEDTA强化酱油的感官评价得分较高，与空白酱油得分相似，明显高于FeSO4强化酱油，说明NaFeEDTA对2种工艺酱油的感官影响均低于FeSO4。     

Sensory characteristics and iron dialyzability of gluten-free bread fortified with iron

The objectives of the present study were (a) to produce gluten-free bread, fortified with iron (GFB-Fe), using selected iron compounds (ferric pyrophosphate, ferric pyrophosphate with emulsifiers, NaFeEDTA, electrolytic iron, ferrous gluconate, ferrous lactate and ferrous sulphate) (b) to test sensory characteristics of the GFB-Fe (feel-mouth texture, crumb colour, aroma and taste) (c) to compare iron dialyzability of various iron compounds in GFB-Fe. The most acceptable products were those fortified with ferric pyrophosphate with emulsifiers and ferric pyrophosphate. Ferrous dialyzable iron (ferrous iron with molecular weight lower than 8000 Da, an index for prediction of iron bioavailability) was measured under simulated gastrointestinal conditions. Ferrous dialyzable iron in GFB-Fe fortified with ferric pyrophosphate with emulsifiers, NaFeEDTA, ferrous bis-glycinate, ferrous gluconate or ferrous sulphate was higher than that in GFB-Fe fortified with electrolytic iron, ferrous lactate or ferric pyrophosphate (P < 0.05). These results are promising for the development of GFB-Fe products in the future.     

Iron fortification of finger millet (Eleucine coracana) flour with EDTA and folic acid as co-fortificants

Fortification of staple foods with iron is a feasible strategy to enhance the intake of this mineral. In the present investigation, finger millet flour was explored for its suitability as a vehicle for fortification with iron. Ferrous fumarate and ferric pyrophosphate were added at levels that provided 6 mg of iron per 100 g of the flour, and both were found to be equally effective. Inclusion of EDTA and folic acid, along with the iron salts, significantly increased the bioaccessibility of iron from the fortified flours. The fortified flours were stable up to a period of 60 days. There was a decline in the bioaccessible iron content in the flour fortified with ferric pyrophosphate after 30 days of storage. Heat processing of the flours improved the bioaccessibility of iron from the unfortified and fortified flours. Fortification with iron did not affect the bioaccessibility of the native zinc from the flours.     

Iron fortification and parboiled rice quality: appearance,cooking quality and sensory attributes

BACKGROUND: Iron (Fe) fortification of parboiled rice increases both Fe concentration and bioavailability in milled grains (i.e. white rice). The aim of the present study was to evaluate parboiled rice fortified with 250 and 450 mg Fe kg^?1 paddy rice for its pre‐cooking appearance, cooking quality, basic sensory attributes and overall acceptance in comparison with unfortified parboiled rice in Thailand and local parboiled rice in Bangladesh. RESULTS: Fe fortification at 250 mg Fe kg^?1 paddy rice significantly elevated Fe concentration in white rice to as high as 19.1 mg Fe kg^?1 white rice, compared with 6.2 mg Fe kg^?1 white rice for unfortified parboiled rice, without any adverse impact on consumer acceptance based on the current preliminary assessment. The added Fe was well retained in the cooked rice, with significant residual value for human intake. Panellists in Thailand and Bangladesh did not detect significant differences in the acceptability of parboiled rice fortified at 250 mg Fe kg^?1 paddy rice compared with unfortified and local parboiled rice respectively. However, Fe fortification of parboiled rice at the higher level of 450 mg Fe kg^?1 paddy rice significantly intensified the yellow colour of the grain and changed the off‐flavour, chewiness and flakiness of the cooked Fe‐fortified parboiled rice. This resulted in a low acceptability ranking of parboiled rice fortified at 450 mg Fe kg^?1 paddy rice by panellists in both Thailand and Bangladesh. CONCLUSION: Fe fortification of parboiled rice at an appropriate level (e.g. 250 mg Fe kg^?1 paddy rice) is dosage‐effective and acceptable to rice consumers. Consumer acceptability of Fe‐fortified parboiled rice is closely related to pre‐cooking appearance, cooking quality and sensory attributes. Copyright © 2009 Society of Chemical Industry     

EFFECT OF PACKAGING MATERIALS ON THE QUALITY OF IRON-FORTIFIED WHOLEMEAL FLOUR DURING STORAGE

ABSTRACT

The effect of packaging materials on the physicochemical and rheological characteristics of iron‐fortified wholemeal flour (WMF) during storage was determined. WMF was fortified with three fortificants, namely ferrous sulfate (30 ppm), ferrous sulfate + ethylenediamine tetraacetic acid (EDTA) (20 + 20 ppm) and elemental iron (60 ppm). Each flour was also fortified with 1.5 ppm folic acid. Moisture, flour acidity and peroxide value increased during storage, while protein and fat contents decreased. Highest conversion of Fe²⁺ into Fe³⁺was observed in flour fortified with ferrous sulfate (2.72%), followed by that fortified with ferrous sulfate + EDTA (1.49%) and elemental iron (1.06%). Water absorption and dough viscosity of iron‐fortified flours increased during storage. The flour containing ferrous sulfate was most acceptable regarding sensory characteristics, followed by samples containing ferrous sulfate + EDTA. Fortified flours were more stable during storage than unfortified. Addition of EDTA increased the stability of flours and fortificants. The fortified flours stored in polypropylene bags proved more stable than those stored in the tin boxes.

PRACTICAL APPLICATIONS

The main role of packaging is to protect the product during handling, distribution and storage against environmental and mechanical hazards. The success of a fortification program depends on the stability of micronutrients and food to which these are added. Chemical changes during storage badly affect chapatti making and sensory properties. Exposure of the fortificant to any factor including heat, moisture, air or light, and acid or alkaline environments during processing, packaging, distribution, or storage affects its stability. Flour containing elemental iron and ferrous sulfate with EDTA remained stable up to 42 days. The unfortified flour and flour containing ferrous sulfate remained stable for 21 days in tin boxes and 28 days in the polypropylene bags. Wheat flour milling industry would be benefited from this research if government is keen to launch iron fortification program in the country to curb iron deficiency anemia among population.

     

Bioavailability of iron-milk-protein complexes and fortified cheddar cheese

Iron fortification is used to increase dietary iron intake. Dairy products are widely consumed but contain almost no iron. Cheddar cheese was fortified with ferric chloride or iron-casein, ferripolyphosphate-whey protein, and iron-whey protein complexes. Hemoglobin regeneration efficiency was determined to evaluate iron bioavailability. Maximal and basal iron bioavailabilities were measured in anemic weanling rats fed low iron diets (about 22 mg iron/kg) and normal adult rats fed high iron diets (about 145 mg iron/kg) of iron density (32 mg iron/1000 kcal) found in some high iron human diets. Maximal iron bioavailabilities for ferric chloride or iron-casein, ferripolyphosphate-whey protein, and iron-whey protein complexes were 85, 71, 73, and 72%, respectively, and for the respective iron-fortified cheeses they were 75, 66, 74, and 67%. Differences were not significant in maximal iron bioavailabilities among iron sources and between fortified cheeses and fortification iron sources. Basal iron bioavailabilities for 10-d feeding of the respective fortification iron sources were 5, 8, 6 and 7%, respectively, and 4, 4, 3, and 3% for 14 d feeding; the differences among the iron sources were not significant. Maximal and basal iron bioavailabilities of ferrous sulfate were 85 and 5%, respectively. Practical implications of these observations are discussed.