WO2020201908A1

WO2020201908A1 - Encapsulated micronutrient granules for fortification of edible salt compositions

Info

Publication number: WO2020201908A1
Application number: PCT/IB2020/052746
Authority: WO
Inventors: M. N. Shashikala; Satyanarayana Reddy Jaggavarapu
Original assignee: Tata Chemicals Limited
Priority date: 2019-04-01
Filing date: 2020-03-24
Publication date: 2020-10-08

Abstract

The present disclosure relates to substantially encapsulated micronutrient granules for fortification of an edible salt composition. Said substantially encapsulated micronutrient granules comprise of at least one micronutrient having a particle size in a range of 10 to 250 microns, wherein said micronutrient is encapsulated by an outer coating comprising of a fatty acid and a cellulose derivative.

Description

ENCAPSULATED MICRONUTRIENT GRANULES FOR FORTIFICATION OF

EDIBLE SALT COMPOSITIONS

Field of Invention

The present disclosure relates to fortified edible salt compositions. In particular, the present disclosure relates to substantially encapsulated micronutrient granules for fortification of an edible salt composition.

The present application is a patent of addition of pending Indian Patent Application No. IN201821011987.

Background

Iron and iodine are essential elements for the human body. Iron acts as a catalyst in the transport, storage and utilization of oxygen. Iron is found in hemoglobin, myoglobin, cytochrome and in other enzymes and iodine is an essential component of thyroid hormones.

Iron deficiency (anemia) and iodine deficiency disorders often coexist and affects more than one third of the world’s population in the developing as well as industrialized nations, with serious consequences on mental and physical development. A food source fortified with iron and iodine can help to overcome such problems by ensuring a daily supply of these minerals.

Edible salt is an ideal food vehicle for such a fortification owing to its low cost and ubiquitous use. Iron and iodine fortified common salt can be used for the treatment of iron and/or iodine deficiency disorders. However, double fortification of salt with iron and iodine involves various problems. One such problem is catalytic reduction of iodate to iodine in presence of ferrous ions and oxygen which leads to sublimation of iodine and co-oxidation of ferrous to ferric leading to unacceptable color and sensorials in salt matrix. It is known that such problems can be overcome by encapsulating or chelating iron to create a physical barrier for the iodine source. Zimmermann et al (Dual fortification of salt with iodine and microencapsulated iron: a randomized, double-blind, controlled trial in Moroccan schoolchildren. Am J Clin Nutr. 2003;77:425-32.) have conducted randomized, double-blind, controlled trial in Moroccan schoolchildren, with double fortified salt that contained encapsulated ferrous sulphate with partially hydrogenated vege;. oil. There was unacceptable color development in salt with no significant organoleptic changes.

W02002080706 discloses a food additive particle comprising a) an inorganic, porous core in which one or more water-soluble functional ingredients are impregnated, and b) a hydrophobic, water-insoluble outer coating having a melting point of greater than 100°C and comprising one or more multivalent metal salts of fatty acids of chain length not less than 8.

US2017216216A1 provide particles of micronutrients and vitamins encapsulated within heat resistant pH-sensitive water-insoluble polymers, such as EUDRAGIT®, which are packaged within a salt shell.

However, encapsulation formulations developed so far are expensive and hence the price of double fortified salt is significantly higher and unlikely reaching the customers intended i.e lower income groups where both iron and iodine deficiency disorders are common. Further, the stability of both iron and iodine in such formulations is not very promising when it comes to long term storage. Such formulations also do not have good sensorial properties when added to many food matrixes.

Additionally, known formulations have density lower than that of refined salt which have density ranging from 1.2 to 1.5 g/cm³. This causes unacceptable floating of the formulation in the cooking matrix. Further, this difference in density causes separation of the formulation from salt during transportation resulting in non-uniform distribution of formulation in the salt.

Therefore, there is a need for an inexpensive and fortified edible salt composition which not only exhibits improved micronutrient-iodine stability for long term storage, but is also capable of uniform mixing and distribution in salt. Further, there is a need for a simple process for preparing such a composition.

Summary

The present disclosure relates to substantially encapsulated micronutrient granules for fortification of an edible salt composition. Said substantially encapsulated micronutrient granules comprises of at least one micronutrient having a particle size in a range of 10 to 250 microns, wherein said micronutrient is encapsulated by an outer coating comprising of a fatty acid and a cellulose derivative.

A fortified edible salt composition comprising of said substantially encapsulated micronutrient granules is also disclosed. Said fortified edible salt composition comprises of 98% of an edible salt; 0.1 to 5 % of the encapsulated micronutrient granules; and 0.01 to 0.5 % of an additional micronutrient selected from a group consisting of potassium iodate, potassium iodide, and mixtures thereof.

The present disclosure also relates to a process for preparing said substantially encapsulated micronutrient granules. Said process comprises providing at least one micronutrient having a particle size in a range of 10 to 250 microns; and coating said micronutrient with an outer coating comprising of a fatty acid and a cellulose derivative to obtain said granules.

Brief Description of Figures

Figure 1 shows the Microscopic image (at 200 maginification) of uncoated (after sieving) iron granules, in accordance with an embodiment of the present invention.

Figure 2 shows the Microscopic image (at 200 maginification) of substantially encapsulated iron granules obtained in accordance with an embodiment of the present invention. Figure 3 shows the size (in microns) of granules before and after coating, in accordance with an embodiment of the present invention.

Figure 4 shows the release of iron from substantially encapsulated iron granules obtained in accordance with an embodiment of the present invention at pH 6.8 and 1.3 over a period of time.

Figure 5 depicts the stability of iodine in salt fortified with substantially encapsulated iron granules over a period of time at accelerated conditions of 45 °C and 75% RH (100 days equivalent to 300 days).

Detailed Description

For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alterations and further modifications in the disclosed composition and method, and such further applications of the principles of the disclosure therein being contemplated as would normally occur to one skilled in the art to which the disclosure relates.

It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the disclosure and are not intended to be restrictive thereof.

Reference throughout this specification to“one embodiment”“an embodiment” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrase“in one embodiment”,“in an embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. In its broadest scope, the present disclosure relates to fortified edible salt compositions. In particular, the present disclosure relates to substantially encapsulated micronutrient granules for fortification of an edible salt composition. Said substantially encapsulated micronutrient granules comprise of at least one micronutrient having a particle size in a range of 10 to 250 microns, wherein said micronutrient is encapsulated by an outer coating comprising of a fatty acid and a cellulose derivative.

The disclosed substantially encapsulated micronutrient granules have density and size similar to the edible salt composition. This prevents (i) floating of the substantially encapsulated micronutrient granules when fortified edible salt composition is used in water or a food, and (ii) separation of substantially encapsulated micronutrient granules from fortified edible salt composition while transportation or storage.

In accordance with an aspect, the at least one micronutrient has a particle size in a range of 10 to 250 microns, and preferably 100 to 175 microns. In accordance with an embodiment, said substantially encapsulated micronutrient granules comprises 15 to 25% of the at least one micronutrient, and preferably 20 to 24% of the at least one micronutrient. In accordance with an embodiment, the micronutrient is a micronutrient source material selected from a group consisting of Fe source, Zn source and mixtures thereof, and preferably Fe source. In accordance with an embodiment, said Fe source is a food grade iron containing compound selected from a group consisting of ferrous sulphate heptahydrate, ferrous fumarate, ferrous citrate and mixtures thereof, and is preferably ferrous sulphate hepta hydrate. In accordance with an embodiment, said Zn source is selected from a group consisting of zinc sulphate, zinc gluconate, zinc oxide, zinc stearate.

In accordance with an embodiment, said fatty acid is any fatty acid, which has essentially long hydrocarbon chains containing a carboxyl group at one end and a methyl group at the other. Said fatty acids may be obtained from hydrogenated vegetable or animal oils and are around C16-C20 in length. In accordance with an embodiment, fatty acid is selected from a group consisting of stearic acid, palmitic acid, salts of stearic acid, soy sterene and the like. In accordance with a preferred embodiment, fatty acid is stearic acid. In accordance with an embodiment, cellulose derivative is selected from a group consisting of hydroxyl propyl methyl cellulose (HPMC), hydroxyl ethyl cellulose, hydroxyl methyl cellulose, microcrystalline cellulose, ethyl cellulose and family thereof. In accordance with a preferred embodiment, said cellulose derivative is hydroxyl propyl methyl cellulose.

In accordance with an aspect, the outer coating comprises of a fatty acid and cellulose derivative. Fatty acid acts as a moisture barrier and cellulose derivatives improves the wettability and spreadability of fatty acid. In accordance with an embodiment, the outer coating comprises the fatty acid and cellulose derivative in a ratio ranging between 5: 1 to 1:5, and preferably about 3: 1.

In accordance with an embodiment, the outer coating comprises of one or more consecutive layers of fatty acid and cellulose derivative. In accordance with an alternate embodiment, the outer coating comprises of one or more layers of a blend of the fatty acid and cellulose derivative. In accordance with a preferred embodiment, the outer coating comprises of a blend of the fatty acid and cellulose derivative.

In accordance with an embodiment, the outer coating further comprises of an emulsifier. Any known emulsifier can be used. In accordance with a preferred embodiment, said emulsifier is selected from a group consisting of polysorbate and lecithin.

In accordance with an embodiment, the outer coating further comprises of one or more of a pigment, a taste maker and taste enhancer.

In accordance with an embodiment, said substantially encapsulated micronutrient granules have a particle size in a range of 150 to 800 microns, and preferably 100 to 200 microns.

The present disclosure also relates to a process for preparing substantially encapsulated micronutrient granules for fortification of an edible salt composition. Said process comprises: providing at least one micronutrient having a particle size in a range of 10 to 250 microns; and

coating said micronutrient with an outer coating comprising of a fatty acid and a cellulose derivative to obtain said substantially encapsulated micronutrient granules.

In accordance with an embodiment, at least one micronutrient having the particle size in the range of 10 to 250 microns is obtained by separating micronutrient having the said particle size from a micronutrient source material. Said separation of micronutrient is carried out by subjecting the micronutrient source material to a sieving step. Alternatively, said micronutrient having the said particle size are obtained by granulation to required size.

In accordance with an embodiment, micronutrient source material is selected from a group consisting of Fe source, Zn source and mixtures thereof, and preferably Fe source.

In accordance with an embodiment, the outer coating is applied such that it comprises fatty acid and cellulose derivative in a ratio ranging between 5: 1 to 1 :5, and preferably about 3: 1. In accordance with an embodiment, the outer coating is formed by coating the granules with one or more consecutive layers of the fatty acid and cellulose derivative. In accordance with an alternate embodiment, the outer coating is formed by coating one or more layers of a blend of the fatty acid and cellulose derivative. In accordance with a preferred embodiment, the outer coating comprises of a blend of fatty acid and cellulose derivative.

In accordance with an embodiment, fatty acid is selected from a group consisting of stearic acid, palmitic acid, salts of stearic acid, soy sterene, and preferably stearic acid. In accordance with an embodiment, fatty acid is melted or dissolved in an organic solvents. Said organic solvent is preferably ethanol. Fatty acid, in particular, stearic acid for the purposes of present invention may be obtained from any known commercial sources. In accordance with an embodiment, a blend of fatty acid and cellulose derivative is prepared by in aqueous medium or ethanol-water binary mixture. In accordance with an embodiment, said cellulose derivative is selected from a group consisiting of hydroxyl propyl methyl cellulose, hydroxyl ethyl cellulose, hydroxyl methyl cellulose, microcrystalline cellulose, ethyl cellulose and family thereof, and preferably hydroxyl propyl methyl cellulose. Cellulose derivatives, in particular, hydroxyl propyl methyl cellulose for the purpose of present invention may be obtained from any known commercial sources, such as Dow, Ashland or any local manufacturer.

In accordance with an embodiment, encapsulation of separated micronutrient with the outer coating is carried out in fluid bed coating unit. Alternatively, encapsulation of separated micronutrient with the outer coating can be carried out in wurster coating unit. The granules are uniformly coated by adjusting the viscosity, wettability and ratio of the fatty acid and cellulose derivative.

The present disclosure also relates to a fortified edible salt composition. Said fortified edible salt composition comprises:

98% of an edible salt;

0.1 to 5 % of disclosed substantially encapsulated micronutrient granules; and 0.01 to 0.5 % of an additional micronutrient selected from a group consisting of potassium iodate, potassium iodide, and mixtures thereof.

In accordance with an embodiment, said edible salt includes but is not limited to NaCl, KC1 or mixtures thereof. In accordance with an embodiment, both solar dried salt and vacuum evaporated salt can be fortified using the disclosed substantially encapsulated micronutrient granules.

In accordance with an embodiment, the micronutrient is present in a concentration between 100 to 2000 ppm in the fortified edible salt composition.

Any known process of preparing a fortified edible salt composition can be used. In particular, said fortified edible salt composition are prepared by blending the substantially encapsulated micronutrient granules, edible salt and the additional micronutrient. Specific Embodiments are Described Below

Substantially encapsulated micronutrient granules for fortification of an edible salt composition, said substantially encapsulated micronutrient granules comprising of at least one micronutrient having a particle size in a range of 10 to 250 microns, wherein said micronutrient is encapsulated by an outer coating comprising of a fatty acid and a cellulose derivative.

Such substantially encapsulated micronutrient granules, wherein the outer coating comprises the fatty acid and cellulose derivative in a ratio ranging between 5: 1 to 1 :5.

Such substantially encapsulated micronutrient granules, wherein the fatty acid is stearic acid.

Such substantially encapsulated micronutrient granules, wherein the cellulose derivative is hydroxyl propyl methyl cellulose.

Such substantially encapsulated micronutrient granules, having a particle size in a range of 150 to 800 microns.

Such substantially encapsulated micronutrient granules, having density in a range of 0.9 to 1.2g/cm³.

Such substantially encapsulated micronutrient granules, wherein the micronutrient is selected from a group consisting of Fe source, Zn source and mixtures thereof.

A fortified edible salt composition comprising:

98% of an edible salt;

0.1 to 5 % of said substantially encapsulated micronutrient granules; and 0.01 to 0.5 % of an additional micronutrient selected from a group consisting of potassium iodate, potassium iodide, and mixtures thereof. A process for preparing substantially encapsulated micronutrient granules for fortification of an edible salt composition, the process comprising: providing at least one micronutrient having a particle size in a range of 10 to 250 microns; and

coating said micronutrient with an outer coating comprising of a fatty acid and a cellulose derivative to obtain said granules

Such process, wherein the outer coating comprises the fatty acid and cellulose derivative in a ratio of 5: 1 to 1 :5.

Such process, wherein the fatty acid is stearic acid.

Such process, wherein the cellulose derivative is hydroxyl propyl methyl cellulose.

Such process, wherein the at least one micronutrient having the particle size in a range of 10 to 250 microns is obtained by separating said micronutrient having said particle size from a micronutrient source material.

Such process, wherein the micronutrient is selected from a group consisting of Fe source, Zn source and mixtures thereof.

In order that this invention may be better understood, the following examples are set forth. These examples are for the purpose of illustration only and the exact compositions, methods of preparation and embodiments shown are not limiting of the invention, and any obvious modifications will be apparent to one skilled in the art.

Examples

Example 1: Preparation of substantially encapsulated micro nutrient granules

200 grams of Ferrous sulphate hepta hydrate was taken and the powder was sieved. Particles of size 100 to 250 microns were sieved and collected. Aqueous based coating solution was prepared using hydroxyl propyl methyl cellulose (HPMC) and stearic acid. 4 grams of HPMC was dissolved in 83 mililitre water. 13 grams of stearic acid was melted and added to HPMC solution under continuous stirring and at elevated temperatures (70 °C). Tween 80 was added as emulsifier. After 10 minutes, solution was cooled to ambient temperature. Percentage of solids in solution was maintained at 16%. Viscosity of solution was measured to be 27cps. The above said solution was used to coat the particles. Coating was done on lab model Unifluid mini fluid bed dryer of 250 grams capacity. 150 grams of material of specified size was loaded into the fluid bed dryer. Coating was done till the particle size increased by 100 microns.

Observation: Analysis of tap density and iron content was done and noted to be 0.94 and 16%. Color of granules observed to be white to off white.

Figure 1 shows the Microscopic image (at 200 maginification) of uncoated (after sieving) iron granules. Figure 2 shows the Microscopic image (at 200 maginification) of the substantially encapsulted iron granules. The substantially encapsulted iron granules were found to be uniformly encapsulated.

Figure 3 shows the size of granules before and after coating. As shown in Figure 3, there was an increase in particle size of granules after coating.

Example 2: Preparation of substantially encapsulated micronutrient granules

200 grams of Ferrous sulphate hepta hydrate was taken and the powder was sieved. Particles of size 100 to 250 microns were sieved and collected.

Ethanol/water based coating solution was prepared using hydroxyl propyl methyl cellulose (HPMC) and stearic acid. 4 grams of HPMC was dissolved in 63 mililitre water. 13 grams of stearic acid was dissolved in 30 mililitre of ethanol at 70 °C temperatures and added to HPMC solution under continuous stirring and at elevated temperatures (70 °C). Tween 80 was added as emulsifier. After 10 minutes, solution was cooled to ambient temperature. Percentage of solids in solution was maintained at 16%. Viscosity of solution was measured to be 35cps. The above said solution was used to coat the particles. Coating was done on lab model Unifluid mini fluid bed dryer of 250 grams capacity. 150 grams of material of specified size was loaded into the fluid bed dryer. Coating was done till the particle size increased by 100 microns.

Observation: Analysis of tap density and iron content was done and noted to be 0.90 and 16%. Color of granules observed to be white to off white.

Example 3: Preparation of substantially encapsulated micronutrient granules

Ethanol/water based coating solution was prepared using hydroxyl propyl methyl cellulose (HPMC) and stearic acid. 4 grams of HPMC was dissolved in 63 mililitre water. 17 grams of stearic acid was dissolved in 40 mililitre of ethanol at 70 °C temperatures and added to HPMC solution under continuous stirring and at elevated temperatures (70 °C). Lecithin was added as emulsifier. After 10 minutes, solution was cooled to ambient temperature. Percentage of solids in solution was maintained at 16%. Viscosity of solution was measured to be 50cps. The above said solution was used to coat the particles. Coating was done on lab model Unifluid mini fluid bed dryer of 250 grams capacity. 150 grams of material of specified size was loaded into the fluid bed dryer. Coating was done till the particle size increased by 100 microns.

Observation: Analysis of tap density and iron content was done and noted to be 0.91 and 16%. Color of granules observed to be white to off white.

Example 4: Preparation of substantially encapsulated micronutrient granules

Ethanol/water based coating solution was prepared using hydroxyl propyl methyl cellulose (HPMC) and stearic acid. 4 grams of HPMC was dissolved in 63 mililitre water. 13 grams of stearic acid was melted and added to HPMC solution under continuous stirring and at elevated temperatures (70 °C). Tween 80 and lecithin were added as emulsifier. After 10 minutes, solution was cooled to ambient temperature. Percentage of solids in solution was maintained at 16%. Viscosity of solution was measured to be 27cps. The above said solution was used to coat the particles. Coating was done on lab model Unifluid mini fluid bed dryer of 250 grams capacity. 150 grams of material of specified size was loaded into the fluid bed dryer. Coating was done till the particle size increased by 100 microns.

Observation: Analysis of tap density and iron content was done and noted to be 1.1 and 22%. Color of granules was observed to be white to off white.

Example 5: Preparation of substantially encapsulated micronutrient granules

20 Kg of Ferrous sulphate mono hydrate was taken and the powder was sieved. Particles of size 100 to 250 microns were sieved and collected.

Ethanol/water based coating solution was prepared with HPMC. 4 Kg of HPMC was dissolved in 83 Litre water. 13 Kg of stearic acid was melted at 80 °C temperatures and added to HPMC solution under continuous stirring and at elevated temperatures (70 °C). Tween 80 was added as emulsifier. After 30 minutes, solution was cooled to ambient temperature under continuous stirring for further 2 hours. Percentage of solids in solution was maintained at 16%. Viscosity of solution was measured to be 35cps. The above said solution was used to coat the particles. Coating was done on Wruster technology based bottom spray coating unit of capacity 60 Kg. 15Kg of material of specified size was loaded into the fluid bed dryer. Coating was done till the particle size increased by 100 microns.

Observation: Analysis of tap density and iron content was done and noted to be 1.1 and 20%. Color of granules was observed to be white to off white.

Example 6: Preparation of fortified edible salt composition

1 kg Non-iodized salt was blended with KIO3 to give 40ppm of iodine. To this mixture, silica was added as anticaking agent. To this iodised salt, substantially encapsulated micronutrient granules (with iron content 19 to 20%) prepared in Example 5 was added to fortify salt with lOOOppm of iron.

Figure 4 shows the release of iron from substantially encapsulated iron granules at pH 6.8 and 1.3 over a period of time. Iodine stability and color of salt was monitored under accelerated conditions of 45°C and 75% Relative humidity over a period of 3.5 months. Figure 5 depicts the iodine stability in salt fortified with substantially encapsulated iron granules over a period of time at accelerated conditions of 45 °C and 75% RH (100 days equivalent to 300 days). Iodine was found to be stable during this period.

Industrial Applicability

The present disclosure provides substantially encapsulated micronutrient granules for fortification of an edible salt composition. The disclosed substantially encapsulated micronutrient granules provides for effective fortification of edible salt with iron and zinc. The process can further be extended to encapsulate minerals such as copper, selenium etc.

The fortified edible salt composition obtained in accordance with an embodiment of the present invention does not impart any perceivable color and organoleptic changes such as metallic taste. The disclosed fortified edible salt composition when fortified with iron and iodine, retains iodine at satisfactory levels over a period of minimum 9 months while avoiding the problem of discolouration of said substantially encapsulated micronutrient granules.

The present invention is an improvement of the invention claimed in the complete specification of the main Indian Patent application no. IN201821011987. Specifically, the present process eliminates the requirement of extrusion and spheronization, and particles can be encapsulated by suitable coating with coating solution of a fatty acid and a cellulose derivative. Also, the percentage of micronutrient in substantially encapsulated micronutrient granules of present process is at least 15 to 25% higher than the granules disclosed in the main application. This helps in reduction of the amount of substantially encapsulated micronutrient granules required for fortification of edible salt composition. The present process thus provides an economic advantage over that disclosed in the main application. Additionally, the disclosed substantially encapsulated micronutrient granules have density and size similar to the edible salt composition. In accordance with an exemplary embodiment, the micronutrient is iron. Ferrous sulphate heptahydrate and dried ferrous sulphate were taken as iron source material. Density of ferrous sulphate heptahydrate and dried ferrous sulphate is 1.93 and 3g/cm³. When substantially encapsulated micronutrient granules comprising of iron is formed in accordance with the present disclosure, the density of resultant granules reduce by 40 to 50%. Density of coated particles was found to be in a range of 0.90 to 1.2 g/cm³ with particle size of 200 to 400 microns, similar to the size of salt crystals of vacuum salt. In accordance with yet another exemplary embodiment, said substantially encapsulated micronutrient granules have a density of 0.90 to 1.2 g/cm³ and particle size of 200 to 750 microns, similar to the size of salt crystals of refined salt. This prevents floating of the substantially encapsulated micronutrient granules when fortified edible salt composition is used in water or a food; and separation of substantially encapsulated micronutrient granules from fortified edible salt composition while transportation or storage.

The disclosed process of preparing said substantially encapsulated micronutrient granules is simple and inexpensive to perform.

Claims

We Claim:

1. Substantially encapsulated micronutrient granules for fortification of an edible salt composition, said substantially encapsulated micronutrient granules comprising: at least one micronutrient having a particle size in a range of 10 to 250 microns, wherein said micronutrient is encapsulated by an outer coating comprising of a fatty acid and a cellulose derivative.

2. The substantially encapsulated micronutrient granules as claimed in claim 1, wherein the outer coating comprises the fatty acid and cellulose derivative in a ratio ranging between 5: 1 to 1 :5.

3. The substantially encapsulated micronutrient granules as claimed in claim 1 or 2, wherein the fatty acid is stearic acid.

4. The substantially encapsulated micronutrient granules as claimed in claim 1 or 2, wherein the cellulose derivative is hydroxyl propyl methyl cellulose.

5. The substantially encapsulated micronutrient granules as claimed in claim 1, having a particle size in a range of 150 to 800 microns.

6. The substantially encapsulated micronutrient granules as claimed in claim 1, having density in a range of 0.9 to 1.2g/cm³.

7. The substantially encapsulated micronutrient granules as claimed in claim 1, wherein the micronutrient is selected from a group consisting of Fe source, Zn source and mixtures thereof.

8. A fortified edible salt composition comprising:

98% of an edible salt;

0.1 to 5 % of the substantially encapsulated micronutrient granules as claimed in any one of the preceding claims; and

0.01 to 0.5 % of an additional micronutrient selected from a group consisting of potassium iodate, potassium iodide, and mixtures thereof.

9. A process for preparing substantially encapsulated micronutrient granules for fortification of an edible salt composition, the process comprising:

providing at least one micronutrient having a particle size in a range of 10 to 250 microns; and

coating said micronutrient with an outer coating comprising of a fatty acid and a cellulose derivative to obtain said granules.

10. The process as claimed in claim 9, wherein the outer coating comprises the fatty acid and cellulose derivative in a ratio of 5: 1 to 1 :5.

11. The process as claimed in claim 9 or 10, wherein the fatty acid is stearic acid.

12. The process as claimed in claim 9 or 10, wherein the cellulose derivative is hydroxyl propyl methyl cellulose.

13. The process as claimed in claim 9, wherein the at least one micronutrient having the particle size in a range of 10 to 250 microns is obtained by separating said micronutrient having said particle size from a micronutrient source material.

14. The process as claimed in claim 9 or 13, wherein the micronutrient is selected from a group consisting of Fe source, Zn source and mixtures thereof.