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

Abstract

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.

Predicting the Stability of Double Fortified Salt by Determining the Coating Quality of the Encapsulated Iron Premix

“…e fat layer is unaffected at this pH, but ferrous fumarate is soluble [14]. Briefly, 0.1 g of iron premix was carefully weighed into 50-mL glass tubes, and 40 mL of 0.0001 M HCl solution was added and placed in a water bath at 37 °C with constant stirring.…”

“…Previously reported analytical data were used to support this study and are available online and identified with DOI. ese prior studies are cited at relevant places within the text as references [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

“…Additionally, the oxidation of exposed iron can change white salt crystals' colour and reduce their acceptability by consumers [13]. A field-based investigation conducted by Modupe et al [14] detailed on the stability of iodine and iron double fortified salt in Kenya's coastal region. A sample of fortified salt sample developed pink and purple spots.…”

“…Improving the coating quality and developing a moisture-resistant physical barrier can prevent the interaction of added iron and iodine in iodized salt [16]. Moreover, the encapsulation of iron prevents undesirable organoleptic changes in food where exposed iron can contribute to undesirable organoleptic properties and impart metallic taste by iron-mediated chelation-redox reactions [14,17]. Consumer education in ensuring consumer acceptance of double fortified salt for health benefits is also considered essential.…”

Ferrous Pyrophosphate and Mixed Divalent Pyrophosphates as Delivery Systems for Essential Minerals

“…However, these Fe­(II) sources are not ideal for foods that are highly sensitive to color and flavor changes due to their high solubility, which increases iron reactivity with food . On the other hand, encapsulation of these iron sources is often not preferred due to high costs. − …”