Mineral fortification process and its uses

Abstract

A non-micellar mineral-protein complex including an exogenously added mineral and a protein, where the mineral-protein complex is soluble in a solution at a physiological pH between 6.6 to 6.9 and the complex includes exogenous phosphorus.

Claims

1. A soluble mineral-protein complex comprising: calcium; milk protein comprising casein in the form found in milk; a mineral selected from the group consisting of iron, zinc, copper, manganese, magnesium, selenium and chromium; and orthophosphorus, wherein a ratio of the milk protein to the calcium is at least 45:1, wherein the mineral is bound to the casein in the form found in milk, wherein the mineral bound to the casein in the form found in milk is greater than 1 wt. % of the soluble mineral-protein complex, wherein the casein and the orthophosphorus are in a weight ratio between 32:1 and 6.25:1.

2. The soluble mineral-protein complex of claim 1, wherein the mineral is iron.

3. The soluble mineral-protein complex of claim 2, wherein the iron is ferric iron.

4. The soluble mineral-protein complex milk product of claim 1, wherein the mineral bound to the casein in the form found in milk is between 1 wt. % to 20 wt.% of the soluble mineral-protein complex.

5. The soluble mineral-protein complex of claim 1, wherein the mineral bound to the casein in the form found in milk is between 1 wt. % to 9 wt. % of the soluble mineral-protein complex.

6. A method of manufacturing a soluble mineral-protein complex including: calcium; milk protein comprising casein in the form found in milk; a mineral selected from the group consisting of iron, zinc, copper, manganese, magnesium, selenium and chromium; and orthophosphorus, wherein a ratio of the milk protein to the calcium is at least 45:1, wherein the mineral is bound to the casein in the form found in milk, wherein the mineral bound to the casein in the form found in milk is greater than 1 wt. % of the soluble mineral-protein complex, wherein the casein and the orthophosphorus are in a weight ratio between 32:1 and 6.25:1; wherein the soluble mineral-protein complex is soluble in a solution at a physiological pH between 6.6 to 6.9, the method comprising: a) adding the orthophosphorus to the milk protein; and b) adding the exogenous mineral to the milk protein to form the soluble mineral-protein complex.

7. The method as claimed in claim 6, wherein the casein is provided by at least one compound selected from the group consisting of sodium caseinate, potassium caseinate, ammonium caseinate, lactic casein, derivatives of caseins, and fractions of caseins.

8. The method as claimed in claim 6, wherein the method comprises dissolving the milk protein in water to form a solution.

9. The method as claimed in claim 8, wherein the milk protein concentration in the solution is between 1-12.5% w/v.

10. The method as claimed in claim 8, wherein the orthophosphorus is added to the solution prior to the addition of the mineral.

11. The method as claimed in claim 6, wherein the orthophosphorus is provided by K2H PO4.

12. The method as claimed in claim 8, wherein an amount of orthophosphorus is added to the solution such that the ratio of the milk protein to the orthophosphorus is between 5:1 to 130:1.

13. The method as claimed in claim 6, wherein the ratio of the milk protein to the orthophosphorus is between 7:1 to 90:1.

14. The method as claimed in claim 6, wherein the mineral is added to the mixture resulting from step a).

15. The method as claimed in claim 6, wherein the mineral is iron.

16. The soluble mineral-protein complex of claim 1, wherein the ratio of the milk protein to the calcium is equal to or greater than 58:1.

17. The soluble mineral-protein complex of claim 1, wherein the soluble mineral-protein complex is made by a process comprising removing at least 70 wt. % of the calcium from milk comprising the milk protein.

18. The soluble mineral-protein complex of claim 1, wherein the ratio of the milk protein to the calcium is between 70:1 and 95:1.

19. The soluble mineral-protein complex of claim 1, wherein the mineral bound to the casein is 4 wt. % to 8 wt. % of the soluble mineral-protein complex.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which:

(2) FIG. 1 A preferred method for manufacture of complex I;

(3) FIG. 2 A preferred method for manufacture of complex II;

(4) FIG. 3 Effect of iron addition on the levels of soluble protein;

(5) FIG. 4 Effect of iron addition on the levels of soluble iron;

(6) FIG. 5 Effect of iron addition on the turbidity of sodium caseinate solution;

(7) FIG. 6 Photograph 1 to illustrate the advantages of complex II;

(8) FIG. 7 Photograph 2 to illustrate the advantages of complex II;

(9) FIG. 8 Effect on protein solubility upon iron fortification using complex I;

(10) FIG. 9 Effect on iron solubility upon iron fortification using complex I; and

(11) FIG. 10 Effect of protein solubility upon exogeneous phosphorus addition.

DETAILED DESCRIPTION

Example 1: Physico-Chemical Properties and Composition of 70% Calcium Removed Milk (Used for Complex I)

(12) TABLE-US-00001 Parameters Specification Colour Greenish translucent liquid pH 6.80 Total solids 10% w/w Viscosity (20° C.) 1.28 Pascal seconds (50 shear) % Ca removed 70% w/w Heat stability Heat Stable (90° C. for 30 min or 140° C. for 5 seconds) Protein 3.12% w/w Soluble protein 96% w/w Zeta potential (100 X −45.58 dilution) Z-avg diameter value 173 nm Ca 300-350 mg/kg Mg 40.7 mg/kg K 2500 mg/kg P 940 mg/kg Na 642 mg/kg

Example 2: Physico-Chemical Properties and Composition of an Exemplary Soluble Mineral Protein Complex from a Milk-Derived Liquid Source

(13) TABLE-US-00002 Parameters Specification Colour Yellowish liquid pH 6.80 Total solids 10% w/w Viscosity (20° C.) 1.33 Pascal seconds (50 shear) % Ca removed 70% w/w Heat stability Heat Stable (90° C. for 30 min or 140° C. for 5 seconds) Protein 3.10% w/w Soluble protein 93% w/w Zeta potential (100 X −48 dilution) Z-avg diameter value 120 nm Ca 300-350 mg/kg Mg 40.7 mg/kg Fe 1675 mg/kg Fe/Protein Ratio % 3.3% K 2500 mg/kg P 2000 mg/kg Na 1400 mg/kg

Example 3: Examples to Illustrate the Amount of Each Complex Needed to Achieve Maximum Iron Fortification Levels According to RDI's

(14) The table below outlines existing permission for iron fortification in different foods.

(15) TABLE-US-00003 Quantity of Iron-protein Maximum claim complex 1 or 2 powder Reference per reference to be added Food quantity quantity (% RDI) Complex 1 Complex 2 Amount of Iron in — — 1.8% 7.5% powder Biscuits containing  35 g 3.0 mg (25%) 166 mg 40 mg not more than 200 g/kg fat & 50 g/kg sugar Cereal Flours  35 g 3.0 mg (25%) 166 mg 40 mg Bread  50 g 3.0 mg (25%) 166 mg 40 mg Pasta  35 g 3.0 mg (25%) 166 mg 40 mg uncooked Extracts of meat,  5 g 1.8 mg (15%) 100 mg 24 mg vegetables or yeast Analogues of meat 100 g 3.5 mg (30%) 194 mg 100 mg  derived from legumes Formulated 600 ml 3.0 mg (25%) 166 mg 47 mg Beverages Formulated meal One meal 4.8 mg (40%) 266 mg 64 mg replacements servings Formulated One serving 6.0 mg (50%) 333 mg 80 mg supplementary foods Formulated One day  12 mg (100%) 666 mg 160 mg  supplementary quantity sports foods

(16) The recommended daily intake (RDI) for iron is 12 mg.

(17) The table also illustrates the amount of each complex which is required to be added (in powder form) to the food to achieve the maximum iron fortification for each product. This exemplified the versatility of the complexes and their use. It also shows the advantage of being able to load higher amounts of iron into the complexes, as less powder is needed to achieve high iron fortification in the food.

Example 4: Effect of Phosphorus Addition to the Complex

(18) FIGS. 3 to 5 illustrate the effect of adding phosphorus to the complex.

(19) FIG. 3 shows how the protein solubility is affected as iron levels increase from 1 to 20 mM (equivalent to 6.9% iron). As illustrated, as phosphorus levels are increased from 0 mg/kg through to 2000 mg/kg, the protein solubility is significantly improved, regardless of the increase in iron loading.

(20) FIG. 4 similarly shows the effect on solubility of the iron in a sodium caseinate solution. Again, as phosphorus levels are increased, the solubility of iron is improved significantly.

(21) FIG. 5 illustrates the advantages of the invention, wherein an increase in turbidity indicates a reduction in stability due to the formation of small particulates/precipitates. As the amount of phosphorus is increased, the turbidity can be reduced close to baseline even upon loading up to 25 mM (6.9%) iron, indicating that all the protein is remaining in a soluble and stable form.

(22) Based on these preliminary results, the inventors foresee that a particularly optimal level of mineral loading (e.g. iron) may be about 15 mM (4%). This may provide the best balance between stability and loading for many commercial applications. However, increases beyond 15 mM (4%) are clearly possible and may be viable for particular applications as discussed in Example 3 above.

Example 5: Visual Representation of Effect of Phosphorus Addition to Sodium Caseinate

(23) FIGS. 6 and 7 visually illustrate how addition of phosphorus improves the solubility and stability of the complex. Even when the iron is loaded up to 25 mM, the composition remains in solution. Without the phosphorus, the protein and/or iron precipitates even at lower levels of iron (5-10 mM).

(24) Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope of the appended claims.

Example 6: Testing of Other Minerals

(25) Zinc

(26) We have compared the effect of zinc sulphate addition on the precipitation of proteins in sodium caseinate using our technology.

(27) Upon addition of zinc sulphate to sodium caseinate solution (2% protein), not more than 5 mM of zinc could be added without gross precipitation of proteins at pH 6.8.

(28) However, as exemplified with the concept of complex II, we could add 18 mM of zinc to the sodium caseinate (2% protein solution) without any precipitation of proteins.

(29) Copper

(30) The sodium caseinate solution (2% protein) precipitated upon addition of 1.5 mM copper as copper sulphate. Again using the concept of complex II, we could add 4 mM without noticeable precipitation at pH 6.8.

Example 7: Heat Stability and Sensory Analysis of Complex I

(31) An iron-protein complex according to “Complex I” was added to whole milk powder (WMP) at a level equivalent to 37.5 mg iron per 100 g WMP. This was then reconstituted to 12% solids using water, equivalent to natural milk. This provided a final iron concentration of 4.5 mg per 100 ml serving, equivalent to 25% of the RDA for menstruating women or 56% of the RDA for adult males and postmenopausal women.

(32) The reconstituted WMP was then pasteurized at 75° C. for 15 seconds, filled into plastic bottles (1 litre) and stored at 4° C. for 7 days. It was then assessed for functional and sensory characteristics as follows: Fortified milk and un-fortified control milk had no difference in colour as measured by Minolta. Sensory assessment found no difference in colour or taste between the fortified and control products. Tea: a tea bag was brewed for 4 min in 180 ml boiling water. 20 ml cold milk was added and stirred. Sensory assessment found no difference in colour or taste between the tea made with the fortified or un-fortified control milk. Dark coffee: 2 scoops ground plunger coffee was brewed for 2 min in 300 g boiling water. 20 g of this brewed coffee was then added to 50 g boiling milk. Sensory assessment found no difference in taste between the dark coffee made with the fortified or un-fortified control milk. However, there was a significant change in colour between the two milks, with the fortified milk causing the coffee to turn a dark grey. Milky coffee: 2 scoops ground plunger coffee was brewed for 2 min in 300 g boiling water. 20 g of this brewed coffee was then added to 100 g boiling milk. Sensory assessment found no difference in taste between the milky coffee made with the fortified or un-fortified control milk. However, there was a significant change in colour between the two milks, with the fortified milk causing the coffee to turn a dark grey.

(33) In an additional study, the reconstituted WMP was UHT processed at 140° C. for 5 seconds, filled into plastic bottles (1 litre) and stored at 4° C. for 7 days. Sensory testing on the milk showed a small difference in taste between the fortified and un-fortified control products, but this was not rated as an unpleasant difference. There was no difference in colour. The fortified product could also be added to tea and dark coffee without any differences in taste, although there was a small negative effect on the taste of milky coffee. There were significant colour differences in the coffee products.

(34) Separately, chocolate mix (Nestle Nesquik) was added to the reconstituted WMP at a concentration of 6 g Nesquik in 100 g milk. The chocolate-flavored milks were then pasteurized at 75° C. for 15 seconds, filled into plastic bottles (1 litre) and stored at 4° C. for 2 days. Sensory assessment showed a small but acceptable change in colour and no difference in flavor between the fortified and un-fortified control milks. In addition, the chocolate-flavored milks were UHT processed at 140° C. for 5 seconds, filled into plastic bottles (1 litre) and stored at 4° C. for 2 days. Sensory assessment showed a noticeable but acceptable change in colour and no significant difference in flavor between the fortified and un-fortified control milks.

Example 8: Heat Stability and Sensory Analysis of Complex II

(35) An iron-protein complex according to “Complex II” was added to whole milk powder (WMP) at a level equivalent to 37.5 mg iron per 100 g WMP. This was then reconstituted to 12% solids using water, equivalent to natural milk. This provided a final iron concentration of 4.5 mg per 100 ml serving, equivalent to 25% of the RDA for menstruating women or 56% of the RDA for adult males and postmenopausal women.

(36) The reconstituted WMP was then pasteurized at 75° C. for 15 seconds, filled into plastic bottles (1 litre) and stored at 4° C. for 7 days. It was then assessed for functional and sensory characteristics as follows: Fortified milk and un-fortified control milk had no difference in colour as measured by Minolta. Sensory assessment found no difference in colour or taste between the fortified and control products. Tea: a tea bag was brewed for 4 min in 180 ml boiling water. 20 ml cold milk was added and stirred. Sensory assessment found no difference in colour or taste between the tea made with the fortified or un-fortified control milk. Dark coffee: 2 scoops ground plunger coffee was brewed for 2 min in 300 g boiling water. 20 g of this brewed coffee was then added to 50 g boiling milk. Sensory assessment found no difference in colour or taste between the dark coffee made with the fortified or un-fortified control milk. Milky coffee: 2 scoops ground plunger coffee was brewed for 2 min in 300 g boiling water. 20 g of this brewed coffee was then added to 100 g boiling milk. Sensory assessment found no difference in taste between the milky coffee made with the fortified or un-fortified control milk. There was only a very slight difference in colour between the products, but this was not noticeable unless they were directly compared.

(37) In an additional study, the reconstituted WMP was UHT processed at 140° C. for 5 seconds, filled into plastic bottles (1 litre) and stored at 4° C. for 7 days. Sensory testing on the milk showed a small difference in taste between the fortified and un-fortified control products, but this was not rated as an unpleasant difference. There was no difference in colour. The fortified product could also be added to tea, milky coffee and dark coffee without any differences in taste, although there were significant colour differences in the coffee products.

(38) Separately, chocolate mix (Nestle Nesquik) was added to the reconstituted WMP at a concentration of 6 g Nesquik in 100 g milk. The chocolate-flavored milks were then pasteurized at 75° C. for 15 seconds, filled into plastic bottles (1 litre) and stored at 4° C. for 2 days. Sensory assessment showed a small but acceptable change in colour and no difference in flavor between the fortified and un-fortified control milks. In addition, the chocolate-flavored milks were UHT processed at 140° C. for 5 seconds, filled into plastic bottles (1 litre) and stored at 4° C. for 2 days. Sensory assessment showed a noticeable but acceptable change in colour and no significant difference in flavor between the fortified and un-fortified control milks.