Optimization of the color masking and coating unit operations for microencapsulating ferrous fumarate for double fortification of salt.

A new coating formulation was developed to eliminate the factor that caused black spots on the iron premix surface, used for making Double Fortified Salt. The formulation is a suspension of titanium dioxide in soy stearin, prepared with ethanol and dichloromethane and applied with a glass sprayer and pan coater. 0-20% w/w titanium dioxide was suspended in 10% w/w soy stearin/hydroxypropyl methylcellulose. Coating with a suspension of 15% w/w TiO2 in 10% w/w soy stearin ensured that all the TiO2 adheres to the premix surface, giving no chance for the recycling of iron contaminated TiO2, which caused the black spot. The new coating formulation ensured that over 90% iodine in Double Fortified Salt was retained after 6 months at 45 °C, 60-70% RH. The whiteness of the premix (L* = 86.4) matched the Double Fortified Salt whiteness (L* = 86.8). Thus, making the new coating method as effective as the previous in desirable characteristics. More so, the new coating method simplifies the existing method by merging the previous color masking, and double coating steps into one step.

Organoleptic Effects of Salt Fortification with Iron and Iodine: A Review.

This paper reviews the factors governing the addition of iron along with iodine in salt, and the conditions under which the micronutrients remain stable and efficacious with storage and use of salt during cooking. The criteria for assessment include organoleptic changes, iodine and iron stability, and consumer acceptability based on changes to color/taste of food that is prepared with the fortified salt. Double-fortifed salt (DFS) has been provided to some 100 million people, and it has become critical to establish the barriers to full acceptability of this technology. The paper identifies 4 key factors that have an impact on organoleptic and nutrient retention outcomes in DFS: iodine stability and interaction with iron, salt purity, the effect of stabilizers, and the fortification technology used. We can conclude based on different studies on DFS, including outcomes of the studies which were field-tested, a high-quality coating and physical barrier between iron and iodine will significantly affect the effectiveness and sensory attributes of the salt. However, a successful introduction of DFS must be accompanied by consumer education that explains the health benefits of iron and iodine intakes, notwithstanding the change in appearance of the salt and of food made with that salt.

Quadruple fortification of salt for the delivery of iron, iodine, folic acid, and vitamin B12 to vulnerable populations.

A process for simultaneous delivery of iron, iodine, folic acid, and vitamin B12 through salt as a potential and holistic approach to ameliorate anaemia and reduce maternal and infant mortality is presented. Two approaches for adding folic acid and B12 to salt during double fortification with iron and iodine were investigated. Attempts to add both micronutrients through the iodine spray solution were unsuccessful. Hence, folic acid was added through a stabilized iodine solution, and B12 was added through the iron premix. Four approaches used to incorporate B12 into the iron premix were investigated: (1) co-extruding B12 with iron, (2) spraying B12 on the surface of the iron extrudate, (3) adding B12 to the colour masking agent, and (4) adding B12 to the outer coating. Of these approaches, coextrusion (1) was the best, based on the ease of production and stability of fortificants. The salt formulated with the solid iron-B12 premix and sprayed iodine and folic acid solution contained 1000 ppm iron, 50 ppm iodine, 25 ppm folic acid, and 0.25 ppm B12. Over 98% of B12, 93% folic acid, and 94% iodine were retained after 6-month storage in the best formulation. This technology can simultaneously deliver iron, iodine, folic acid, and vitamin B12 in a safe and stable salt enabling public health measures for improved health at a minimal additional cost.

Improving the lives of millions through new double fortification of salt technology.

Micronutrient deficiencies (including iodine and iron deficiency) is a global health problem affecting one third of the world's population. Salt is an ideal carrier for food fortification as it is universally consumed at equal rates, independently of economic status, and it is industrially processed. Addressing iron and iodine deficiencies together is a challenge, due to interaction between iodine and iron, negating the effect of added iodine. This paper explains the development of an improved microencapsulation-based technology to produce iron premix, which, when added to iodized salt, is stable and organoleptically indistinguishable. Ferrous fumarate was extruded, followed by cutting, sieving to achieve a size of 300-710 µm (salt grain size). Agglomerated extrudates were microencapsulated (5% hydroxypropyl methylcellulose and 5% soy stearin) to form iron premix. Microencapsulation ensures that the added micronutrients are stable without interaction or degradation. Double Fortified Salt is formed by blending iron premix with iodized salt (1:200 ratio). This technology was transferred to India for industrial scale-up. The public distribution system was utilized to establish and monitor an efficient distribution network for DFS in a transparent manner. The scale-up process was initially demonstrated in the state of Uttar Pradesh, following its success two more Indian states have started distribution of DFS. At present, the DFS with iron and iodine is reaching 60 million people in India. This important health intervention technology through food fortification has the potential to be scaled globally to ensure a world free from iron deficiency anemia.

Cyclodextrins and their potential applications for delivering vitamins, iron, and iodine for improving micronutrient status.

Cyclodextrins (CDs) have been investigated as potential biopolymeric carriers that can form inclusion complexes with numerous bioactive ingredients. The inclusion of micronutrients (e.g. vitamins or minerals) into cyclodextrins can enhance their solubility and provide oxidative or thermal stability. It also enables the formulation of products with extended shelf-life. The designed delivery systems with CDs and their inclusion complexes including electrospun nanofibers, emulsions, liposomes, and hydrogels, show potential in enhancing the solubility and oxidative stability of micronutrients while enabling their controlled and sustained release in applications including food packaging, fortified foods and dietary supplements. Nano or micrometer-sized delivery systems capable of controlling burst release and permeation, or moderating skin hydration have been reported, which can facilitate the formulation of several personal and skin care products for topical or transdermal delivery of micronutrients. This review highlights recent developments in the application of CDs for the delivery of micronutrients, i.e. vitamins, iron, and iodine, which play key roles in the human body, emphasizing their existing and potential applications in the food, pharmaceuticals, and cosmeceuticals industries.

Enhancing vitamin A stability using saponin-chitosan polyelectrolytes coating: Optimization, characterization, and controlled release.

Microencapsulation has the potential to address the stability issues associated with vitamin A. This study examined the effectiveness of emulsifying a saponin-chitosan polyelectrolyte complex to encapsulate vitamin A. Utilizing response surface methodology (RSM), the effects of the chitosan, saponin, and vitamin A contents on various response variables were measured to optimize the formulation. The optimized emulsion was characterized through fluorescence microscopy, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), storage stability, and release profile. Fluorescence microscopy showed that vitamin A was evenly distributed throughout the optimized emulsion. The polyelectrolyte complex and vitamin A were shown to interact hydrophobically and electrostatically by FTIR analysis. The DSC results verified the effective encapsulation and showed that vitamin A heat stability had been enhanced. Study on storage stability demonstrated that during a 2-month storage period, the encapsulated vitamin A remained stable. Moreover, vitamin A was significantly released from the encapsulated form at pH 1.2, based on release assays. In conclusion, saponin-chitosan polyelectrolyte coating proved to be a potentially useful new material for the stability and applications of vitamin A in a range of formulations.

Evaluating the potential of Hibiscus sabdariffa beverage to address the prevalence of iron deficiency in sub-Saharan Africa.

The potential of Hibiscus sabdariffa L. beverage as a dietary iron source for sub-Saharan Africans was investigated. The target was to provide 6 mg of iron through 250 mL of the beverage daily. However, the iron content of the dried hibiscus calyces was determined to be 9.73 ± 0.31 mg/100 g and from that only ∼30% was extractable, resulting in 0.93 ± 0.19 mg Fe/250 mL of the selected beverage formulation. Therefore, ferrous sulfate was explored as a fortificant. The beverage contains polyphenols which could form non-absorbable chelation complexes with iron during digestion. Subsequently, the effect of polyphenols on the bioaccessibility of native and added iron was assessed using spectrophotometric methods. The presence of iron-polyphenol complexes in samples of the unfortified and fortified beverages, adjusted to pH 6.5 (pH at site of iron absorption in the gut) was established. However, only ∼25% of the added iron was found to be bound in the complex. It was shown that the viability of H. sabdariffa L. beverage as an iron source is impacted by extraction losses and the inhibitory effect of polyphenols. Nonetheless, if iron-polyphenol complexation was reduced/prevented then, a fortified hibiscus beverage could be a useful iron source.

Preparation and characterization of an iron-ß-cyclodextrin inclusion complex: factors influencing the host-guest interaction.

Cyclodextrins have received attention recently due to their superior binding with countless hydrophobic molecules. The host-guest interaction between the cyclodextrin cavity and the hydrophobic component not only facilitates the formation of a strong inclusion complex (IC), but also improves its stability against thermal degradation. The functionality of cyclodextrins for the delivery of hydrophilic components is less explored in comparison. This study discusses the application of ß-cyclodextrin (ßCD) for the delivery of highly bioavailable and hydrophilic iron, ferric sodium EDTA, which exhibits great functionality in the presence of polyphenols and phytates with potential application in food fortification. The formation of IC was dependent on the cyclodextrin amount and alcoholic co-solvent and was influenced by the stirring duration. For ferric sodium EDTA, the highest inclusion rate (IR) of ∼77% was obtained after 72 hours of mixing in 25.4% (v/v) alcohol at a ratio of iron : ßCD of 1 : 6. A higher IR (∼96%) was obtained after 6 hours of stirring with less soluble ferrous ammonium phosphate in comparison. The melting temperature (Tm) of the ferrous ammonium phosphate complex increased from ∼172 to ∼294 °C. The high IR and enhanced thermal resistance of the complex make ßCDs potential carriers for ferrous ammonium phosphate delivery and fortification of foods processed at high temperatures.

Optimisation of polymer coating process for microencapsulating ferrous fumarate for salt double fortification with iodine and iron.

An extrusion-based encapsulation process has been developed for making salt grain-sized iron premix for salt fortification. The first step of extrusion agglomeration process has been studied and reported previously. The focus of this study is on the optimisation of the colour-masking and polymer coating steps. Several colour-masking techniques and polymer encapsulants were investigated at various encapsulation levels. Salt samples prepared by blending the resulting iron premixes with iodised salt retained more than 90% of the original iodine and more than 93% of the ferrous iron after 3 months storage at 35°C and 60% relative humidity (RH). Hydrophilic coatings such as hydroxypropyl methyl cellulose (HPMC) offered more protection at the 10% encapsulation level compared to other coating materials studied. All iron premix formulations exhibited high particle density, good bioavailability and acceptable organoleptic properties. The process using the most effective formulations and optimised operation parameters is ready for pilot scale testing and field studies.

Curcumin, a potent therapeutic nutraceutical and its enhanced delivery and bioaccessibility by pickering emulsions.

Curcumin is a biomolecule with functional moieties, which contribute to its anti-inflammatory, anticancer, and antioxidant properties. It has shown several therapeutic effects on treating inflammatory and neurodegenerative diseases and contributes to the reduction of oxidative stress and damage to body tissues. However, its low solubility and fast metabolism limit its absorption in the gastrointestinal (GI) tract and lead to its low bioavailability. Preparation of Pickering emulsions stabilized with mineral or biopolymer-based nanoparticles can be an effective strategy for enhancing the stability of curcumin against degradation, increasing its bioaccessibility in the GI tract, and achieving its controlled release at various locations based on changes in environmental conditions. Various nanoparticles prepared from minerals, proteins, and polysaccharides show potential for stabilizing the curcumin-loaded emulsions, and their wettability can be altered through complexation and formation of hybrid nanoparticles. Stabilization of Pickering emulsions with polysaccharide-based nanoparticles and their complexes can enhance the stability of the curcumin against degradation. Moreover, various protein-based nanoparticles and their conjugated forms with other proteins or polysaccharides can enable the preparation of high internal phase Pickering emulsions (HIPEs) with concomitant higher loading and bioaccessibility of the curcumin molecule. In light of the several therapeutic properties of curcumin, this review article aims to highlight recent studies and the strategies used for the preparation of curcumin Pickering emulsions stabilized by various nanoparticles for enhancing its bioaccessibility during metabolism. These may be useful in pharmaceutical and food industries for drug development and delivery and fortification of food products with this nutraceutical component.

Sensory Trial of Quintuple Fortified Salt-Salt Fortified With Iodine, Iron, Folic Acid, Vitamin B12, and Zinc-Among Consumers in New Delhi, India.

BACKGROUND: Micronutrient deficiencies are a cause of significant public health burden and loss of gross domestic product, especially in developing countries. Multiple fortified salt can potentially address this challenge at scale and in a cost-effective manner. OBJECTIVE: This laboratory-based sensory trial evaluated the acceptability of quintuple fortified salt (Q5FS), that is, iodized salt (IS) fortified with additional 4 micronutrients: iron, folic acid, vitamin B12, and zinc. Iodized salt and double fortified salt (DFS), that is, IS fortified with iron, are used for comparison. METHODS: Forty-five respondents were recruited by open invitations to the university staff and their families. Each study participant rated 10 food items each in a set of 3 identical preparations differing only in the salt used. A 5-point hedonic scale was used to rate each dish on 6 sensory attributes: appearance, color, aroma, taste, texture, and aftertaste. Finally, the dish was rated on the attribute of overall acceptability-a subjective combined score based on all sensory attributes considered together. RESULTS: Among the 3 salt types, there was no difference in scores for the sensory attributes of appearance, aroma, taste, texture, and aftertaste, and the attribute of overall acceptability. Color in IS scored significantly higher than in Q5FS and DFS, but there was no difference between the scores of DFS and Q5FS. CONCLUSIONS: The 3 salts IS, DFS, and Q5FS are comparable to each other in all sensory properties, except for color. This study concludes that Q5FS is organoleptically acceptable under ideal conditions.

Folic acid fortification through existing fortified foods: iodized salt and vitamin A-fortified sugar.

BACKGROUND: Folic acid fortification of cereal-grain products has markedly improved folate status and reduced the risks of neural tube defects and other chronic diseases in the populations participating in fortification programs. To more broadly extend its benefit to affected populations in developing countries, it would seem logical to incorporate folic acid fortification into existing or planned programs to minimize the incremental cost of this intervention. OBJECTIVE: To examine the feasibility of providing folic acid through ongoing programs for salt iodization and vitamin A fortification of sugar. METHODS: Folic acid was added to iodized salt and vitamin A-fortified sugar by various methods--direct blending as a powder, spraying onto the carriers as aqueous solution or suspension, or blending as a microencapsulated premix. The multiple fortified samples were subjected to a prolonged storage stability test, and the retentions of the added micronutrients were followed. RESULTS: Folic acid was generally stable when incorporated into Guatemalan iodized salt and vitamin A-fortified sugar. Even in the presence of encapsulated ferrous fumarate as an iron fortificant, samples retained > 80% in salt and approximately 70% in sugar samples respectively, after 9 months of storage at 40 degrees C and 60% relative humidity. The addition of folic acid as a dry premix made by extrusion was most effective in retaining both folic acid and the other added micronutrients. CONCLUSIONS: The fortification method had a pronounced impact on the stability of both folic acid and the other added micronutrients. Proper encapsulation may be required to ensure the stability of multiple fortified foods.

Feasibility and optimization study of using cold-forming extrusion process for agglomerating and microencapsulating ferrous fumarate for salt double fortification with iodine and iron.

A microencapsulation-based technology platform has been developed for salt double fortification with iron and iodine, aiming to address two globally prevalent micronutrient deficiencies simultaneously. Specifically, ferrous fumarate was microencapsulated into a form of salt grain-sized premix, and then added into iodised salt. The earlier process involved fluidised-bed agglomeration followed by lipid coating. To improve physico-chemical properties of the iron premix, the use of cold-forming extrusion for agglomerating and microencapsulating ferrous fumarate was investigated and optimized in this study, leading to optimal formulations and operation parameters. Grain flours were suitable for forming an extrudable dough incorporating high percentages of ferrous fumarate. All extruded iron particles, regardless of binders used, were rich in iron and had excellent iron in vitro digestibility. The extruded iron particles formed the basis of the final, microencapsulated iron premixes with desired particle size (300-700 µm), and other physical, chemical, nutritional, and organoleptic properties suitable for salt fortification.

Folic acid fortification of double fortified salt.

The addition of folic acid to Double Fortified Salt (with iron and iodine) aims to simultaneously ameliorate three major micronutrient deficiencies in vulnerable populations. To make Triple Fortified Salt, we added folic acid to the iodine solution (first method) and the iron premix (second method) that are used to fortify salt with iron and iodine. When added through the solution, sodium carbonate was needed to dissolve folic acid and to adjust pH. Alternately, folic acid was added either to the iron core or sandwiched between the core and TiO2 layer of the iron premix. Folic acid and iodine were stable in all cases, retaining more than 70% of the added micronutrients after six months at 45 °C/60-70% relative hu. Adding folic acid to the premix's iron core is preferred as folic acid retention was slightly higher, and the added folic acid did not impact the salt's colour. The additional cost for adding the micronutrients to salt is about 27¢/person per year. Folic acid in the fortified salt made with the preferred method was stable in cooking and did not affect selected cooked foods' sensory properties. The technology is a cost-effective approach for simultaneously combating iron, iodine, and folic acid deficiencies.

A spectrophotometric method for determining the amount of folic acid in fortified salt.

Analytical methods for quantifying and monitoring the degradation of micronutrients added to food are crucial to food fortification programs. In the case of folic acid in fortified salts, there are difficulties in developing an effective analytical method due to interference of salt in the standard HPLC methods, as salt precipitates in the HPLC column. To circumvent the problem, a spectrophotometric method was developed to quantify folic acid and monitor its degradation in salt. A distinct absorption wavelength was selected for folic acid in sodium carbonate solution. Of the three wavelengths where maximum absorption was observed for folic acid, 285 nm was selected as being selective for folic acid in the presence of pteroic acid, glutamic acid, aminobenzoic acid, and other products of degradation of folic acid. The method was calibrated for 1-25 µg/mL folic acid (R2 = 1). The recovery was 100 ±â€¯1.2% and 100 ±â€¯1.8% for folic acid in salt and solution, respectively. The limit of detection and quantification for this method is 0.011 µg/mL and 0.033 µg/mL, respectively. The method is accurate, precise, and selective for folic acid in the presence of potential products of folic acid degradation, and is suitable for monitoring folic acid degradation in fortified salt.

Antioxidant system for the preservation of vitamin A in Ultra Rice.

BACKGROUND: Ultra Rice grains are micronutrient-fortified, extruded rice grains designed to address specific nutritional deficiencies in populations where rice is a staple food. Vitamin A and some of the B vitamins, as well as iron and zinc, are target nutrients for fortification through Ultra Rice technology. Vitamin A is sensitive to degradation. Therefore, the original Ultra Rice formulations included stabilizers, some of which were not approved as food additives in all of the receiving markets. OBJECTIVE: To develop a new antioxidant system for improving vitamin A storage stability in Ultra Rice grains, while complying with international food regulations. METHODS: Ten formulations were prepared containing various combinations of hydrophilic and hydrophobic antioxidants, as well as moisture stabilizers. Accelerated vitamin A storage stability tests were conducted at 25 degrees, 35 degrees, and 45 degrees C with 70% to 100% relative humidity. RESULTS: The most stable samples contained one or more phenolic antioxidants, a water-soluble antioxidant, and stabilizing agents. The best results were obtained by using butylated hydroxyanisole (BHA) in combination with butylated hydroxytoluene (BHT) as the hydrophobic antioxidants and ascorbic acid as the hydrophilic antioxidant. Citric acid and sodium tripolyphosphate (STPP) were used to chelate metal ions and to stabilize moisture, respectively. The best formulations retained more than 85% and approximately 70% of the added vitamin A at 25 degrees and 45 degrees C, respectively, after 24 weeks storage. CONCLUSIONS: The best antioxidant system, composed of generally accepted food additives, improved vitamin A stability while reducing the price, thus greatly improving the commercial viability of Ultra Rice grains for use as a ricefortificant.

Iron in vitro bioavailability and iodine storage stability in double-fortified salt.

BACKGROUND: Ferrous fumarate is useful in iron fortification because of its high bioavailability, mild taste, and relatively low cost. A ferrous fumarate premix for incorporation into salt has been developed by agglomerating ferrous fumarate with appropriate binder materials into salt-size particles followed by microencapsulation. OBJECTIVE: The bioavailability of iron is critical for the usefulness of double-fortified salt. This study examined the in vitro bioavailability of various iron forms in double-fortified salt and microencapsulated ferrous fumarate premixes prepared by various techniques in an effort to identify key processing factors affecting iron bioavailability. METHODS: Iron in vitro bioavailability was approximated through the rate of dissolution of iron in 0.1 N HCl, which closely approximates the acid in gastric juice. Iron in vivo bioavailability was tested using the hemoglobin repletion assay in rats. RESULTS: The materials and techniques used in microencapsulating ferrous fumarate had little effect on iron in vitro bioavailability: more than 90% of iron in the premixes was released during 2 hours of digestion in the simulated gastric fluid. By incorporating titanium dioxide in the coating materials, the dark reddish-brown color of ferrous fumarate was effectively masked, resulting in acceptable sensory qualities, while maintaining the stability of iodine in the salt. Iron in vivo tests in rats have confirmed that the ferrous fumarate microencapsulated in a lipid is highly bioavailable, with a bioavailability of 95% relative to ferrous sulfate. CONCLUSIONS: These findings were corroborated by field tests in southern India which demonstrated that double-fortified salt containing microencapsulated ferrous fumarate was effective in reducing the prevalence of iron-deficiency anemia and iodine-deficiency disorders.

Technology for Triple Fortification of Salt with Folic Acid, Iron, and Iodine.

As many of the maternal and child health complications result from folic acid, iron, and iodine deficiencies; it makes sense to combat these simultaneously. We have developed cost-effective technology to deliver these three micronutrients simultaneously through salt. Our goal was to retain at least 70% of the micronutrients during 6 months of storage. The fortified salt was formulated by spraying a solution that contained 2% iodine and 0.5% or 1% folic acid onto salt and adding encapsulated ferrous fumarate. The formulated triple fortified salt contained 1,000 ppm iron, 50 ppm iodine, and 12.5 or 25 ppm folic acid. The spray solution and the salt were stored for 2 and 6 months respectively at 25, 35, and 45 °C 60 to 70% relative humidity. Even at 45 °C, over 70% of both iodine and folic acid were retained in the salt. The best formulation based on the color of the salt and stability of iodine and folic acid contained 12.5 ppm folic acid, 50 ppm iodine, and 1,000 ppm iron. These results indicate that iron, iodine, and folic acid can be simultaneously delivered to a vulnerable population through salt using the technology described. Also, the quality control of the process can be developed around pteroic acid that was detected as a primary degradation product of folic acid. PRACTICAL APPLICATION: The technology developed is already transferred to India for industrial scale up. When fully operational, the technology will simultaneously solve iron, iodine, and folic acid deficiencies in vulnerable populations at a very low cost.

Recovery of phenolic compounds from the by-products of yellow mustard protein isolation.

Nanofiltration (NF) (MWCO 150-300 Da) was evaluated for the recovery of phenolic compounds from the wastewater from the production of yellow mustard protein isolates. Rejection coefficients of 0.70 and 0.87 and transmembrane fluxes of 51.3 L/hm2 and 28.8 L/hm2 were observed under alkaline and acidic conditions, respectively. At low pH, 77% of the phenolic compounds fed to the process were recovered in the retentate. Combination of diafiltration (DF) with NF was beneficial only when processing at low pH. The permeate from the NF process a contained <100 ppm total phenolics, which suggests the possibility of recycling these effluents in the production of yellow mustard protein isolates. p-Hydroxybenzoic acid was the major phenolic compound found both in the waste effluent and in the products of NF processing. Sinapic acid constituted a secondary fraction, and derivatives of quercetin and kaempferol were also detected.

Development of field test kits for determination of microencapsulated iron in double-fortified salt.

BACKGROUND: Efficacy studies have shown that salt double-fortified with iodine and iron can significantly reduce the incidence rates of iron-deficiency anemia and iodine-deficiency disorders. Double-fortified salt can be prepared by mixing microencapsulated iron compounds into conventionally iodated salt. Effective implementation of a double fortification program requires field-based analytical methods to ensure iron levels in double-fortified salt. OBJECTIVE: To develop semiquantitative and qualitative field test kits by adopting standard analytical methods for iron determination to the analysis of iron in double-fortified salt. METHODS: Thermal, mechanical, and chemical strategies were assessed to enable contact between analytical reagents and the encapsulated iron compounds during the analysis. A chemical approach using nonpolar solvents was adopted in semiquantitative and qualitative field tests. The fat coating of the iron premix was removed by solvents, releasing the iron for subsequent colorimetric determination. RESULTS: Both semiquantitative and qualitative field tests were based on initial removal of the microencapsulant, followed by iron quantitation. Solvent dissolution of the coating layer was most useful for rapid release of iron. A semiquantitative field test kit was developed using a mixture of 5% heptane and 95% tetrachloroethylene to free the iron, which was then determined by the 1,10-phenanthroline method. The field test had a useful detection range of 0 to 2,000 ppm of iron. Statistical analyses revealed that the results obtained with the kit correlated well with those obtained by standard laboratory methods (p < .001). A qualitative field test kit was developed to identify the presence of iron. Microencapsulated iron was freed with the use of tetrachloroethylene and then reacted with phenanthroline to form a visually observable coloration on the salt sample. CONCLUSION: Semiquantitative and qualitative field test kits for iron determination in double-fortified salt have been developed and tested. These kits could be useful in quality control of double fortification of salt in small salt-production facilities and in the field, particularly in developing countries.