ANTICAKING AGENT

Abstract

The present invention refers to the use of a calcium carbonate-based composition as an anticaking agent, wherein the calcium carbonate-based composition comprises a first component being a natural ground calcium carbonate or a precipitated calcium carbonate, and a second component being a surface-reacted calcium carbonate, wherein the surface-reacted calcium carbonate is a reaction product of natural ground calcium carbonate or precipitated calcium carbonate with carbon dioxide and at least one H.sub.3O.sup.+ ion donor, wherein the carbon dioxide is formed in situ by the at least one H.sub.3O.sup.+ ion donor treatment and/or is supplied from an external source. Furthermore, the present invention refers to a particulate composition comprising such an anticaking agent, and to a method for producing such a particulate composition.

Claims

1. A method of producing an anticaking agent composition, said method comprising incorporating a calcium carbonate-based composition into said anticaking agent composition, wherein the calcium carbonate-based composition comprises a first component being a natural ground calcium carbonate or a precipitated calcium carbonate, and a second component being a surface-reacted calcium carbonate, wherein the surface-reacted calcium carbonate is a reaction product of natural ground calcium carbonate or precipitated calcium carbonate with carbon dioxide and at least one H.sub.3O.sup.+ ion donor, wherein the carbon dioxide is formed in situ by the at least one H.sub.3O.sup.+ ion donor treatment and/or is supplied from an external source.

2. The method according to claim 1, wherein the calcium carbonate-based composition consists of the first component and the second component.

3. The method use according to claim 1, wherein the weight ratio of the first component to the second component is in the range of 99:1 to 1:99, preferably in the range of 95:5 to 10:90, even more preferably in the range of 90:10 to 20:80, even more preferably in the range of 85:15 to 30:70, and most preferably in the range of 80:20 to 40:60.

4. The method according to claim 1, wherein the first component is a natural ground calcium carbonate selected from the group consisting of marble, chalk, limestone, and mixtures thereof, or wherein the first component is a precipitated calcium carbonate selected from the group consisting of precipitated calcium carbonates having an aragonitic, vateritic or calcitic crystal form, and mixtures thereof.

5. The method according to claim 1, wherein the surface-reacted calcium carbonate is a reaction product of natural ground calcium carbonate selected from the group consisting of marble, chalk, limestone, and mixtures thereof, with carbon dioxide and at least one H.sub.3O.sup.+ ion donor, wherein the carbon dioxide is formed in situ by the at least one H.sub.3O.sup.+ ion donor treatment and/or is supplied from an external source, or wherein the surface-reacted calcium carbonate is a reaction product of precipitated calcium carbonate selected from the group consisting of precipitated calcium carbonates having an aragonitic, vateritic or calcitic crystal form, and mixtures thereof, with carbon dioxide and at least one H.sub.3O.sup.+ ion donor, wherein the carbon dioxide is formed in situ by the at least one H.sub.3O.sup.+ ion donor treatment and/or is supplied from an external source.

6. The method according to claim 1, wherein the at least one H.sub.3O.sup.+ ion donor is selected from the group consisting of hydrochloric acid, sulphuric acid, sulphurous acid, phosphoric acid, citric acid, oxalic acid, an acidic salt, acetic acid, formic acid, and mixtures thereof, preferably the at least one H.sub.3O.sup.+ ion donor is selected from the group consisting of hydrochloric acid, sulphuric acid, sulphurous acid, phosphoric acid, oxalic acid, H.sub.2PO.sub.4.sup.−, being at least partially neutralised by a cation selected from Li.sup.+, Na.sup.+ and/or K.sup.+, HPO.sub.4.sup.2−, being at least partially neutralised by a cation selected from Li.sup.+, Na.sup.+, K.sup.+, Mg.sup.2+, and/or Ca.sup.2+, and mixtures thereof, more preferably the at least one H.sub.3O.sup.+ ion donor is selected from the group consisting of hydrochloric acid, sulphuric acid, sulphurous acid, phosphoric acid, oxalic acid, or mixtures thereof, and most preferably the at least one H.sub.3O.sup.+ ion donor is phosphoric acid.

7. The method according to claim 1, wherein the first component has a volume median particle size d.sub.50 from 0.1 to 50 μm, preferably from 0.5 to 40 μm, more preferably from 0.5 to 20 μm, even more preferably from 0.5 to 10 μm, and most preferably from 0.8 to 8 μm, and/or wherein the first component has a specific surface area of from 0.5 m.sup.2/g to 30 m.sup.2/g, preferably from 1 m.sup.2/g to 20 m.sup.2/g, and more preferably from 1 m.sup.2/g to 10 m.sup.2/g, measured using nitrogen and the BET method.

8. The method according to claim 1, wherein the second component has a volume median particle size d.sub.50 from 0.5 to 50 μm, preferably from 1 to 40 μm, more preferably from 1.2 to 30 μm, and even more preferably from 1.5 to 15 μm, and most preferably from 3 to 10 μm, and/or wherein the second component has a specific surface area of from 15 m.sup.2/g to 200 m.sup.2/g, preferably from 20 m.sup.2/g to 180 m.sup.2/g, more preferably from 25 m.sup.2/g to 160 m.sup.2/g, and most preferably from 70 m.sup.2/g to 120 m.sup.2/g, measured using nitrogen and the BET method.

9. The method according to claim 1, wherein the calcium carbonate-based composition has a residual moisture of less than 10.0 wt. %, preferably less than 7.5 wt. %, and more preferably less than 5.0 wt. %, based on the total weight of the calcium carbonate-based composition.

10. A method of using the anticaking agent composition of to claim 1, said method comprising adding the anticaking agent composition to a base component selected from the group consisting of a food composition, a feed composition, a nutraceutical composition, a pharmaceutical composition and a cosmetic composition.

11. A particulate composition comprising a calcium carbonate-based anticaking composition and a base component, wherein the calcium carbonate-based anticaking composition comprises a first component being a natural ground calcium carbonate or a precipitated calcium carbonate, and a second component being a surface-reacted calcium carbonate, wherein the surface-reacted calcium carbonate is a reaction product of natural ground calcium carbonate or precipitated calcium carbonate with carbon dioxide and at least one H.sub.3O.sup.+ ion donor, wherein the carbon dioxide is formed in situ by the at least one H.sub.3O.sup.+ ion donor treatment and/or is supplied from an external source, wherein the particulate composition comprises the calcium carbonate-based anticaking composition in an amount of from 0.1 to 50 wt. %, preferably in an amount from 0.1 to 20 wt. %, more preferably in an amount from 0.1 to 10 wt. %, even more preferably in an amount from 0.2 to 5 wt. %, and most preferably in an amount from 0.3 to 2.5 wt. %, based on the total weight of the particulate composition.

12. The particulate composition according to claim 11, wherein the calcium carbonate-based anticaking composition consists of the first component and the second component, and/or wherein the weight ratio of the first component to the second component in the calcium carbonate-based anticaking composition is in the range of 99:1 to 1:99, preferably in the range of 95:5 to 20:80, even more preferably in the range of 90:10 to 30:70, even more preferably in the range of 85:15 to 40:60, and most preferably in the range of 80:20 to 50:50.

13. The particulate composition according to claim 11, wherein the base component is selected from the group consisting of a food composition, a feed composition, a nutraceutical composition, a pharmaceutical composition and a cosmetic composition, and preferably is a food composition or a feed composition.

14. The particulate composition according to claim 13, wherein the food composition is food salt, curing salt, salt substitute, milk powder, skimmed milk powder, cream powder, egg powder, whey fat powder, protein powder, vending machine powder, grated cheese, sugar, powdered food flavour, spice, seasoning, packet soup mixture, baking mixture, pudding powder, mousse powder, or sauce powder, or wherein the feed composition is pet food, milk replacer for animals, or mineral salt for animals.

15. A method for the production of a particulate composition, the method comprising the step of mixing a calcium carbonate-based anticaking composition with a base component, wherein the calcium carbonate-based anticaking composition comprises a first component being a natural ground calcium carbonate or a precipitated calcium carbonate, and a second component being a surface-reacted calcium carbonate, wherein the surface-reacted calcium carbonate is a reaction product of natural ground calcium carbonate or precipitated calcium carbonate with carbon dioxide and at least one H.sub.3O.sup.+ ion donor, wherein the carbon dioxide is formed in situ by the at least one H.sub.3O.sup.+ ion donor treatment and/or is supplied from an external source, and wherein the calcium carbonate-based anticaking composition is admixed into the base component in an amount of from 0.1 to 50 wt. %, preferably in an amount from 0.1 to 20 wt. %, more preferably in an amount from 0.1 to 10 wt. %, even more preferably in an amount from 0.2 to 5 wt. %, and most preferably in an amount from 0.3 to 2.5 wt. %, based on the total weight of the particulate composition.

Description

FIGURES

[0283] FIG. 1: Normalized basic flow energy (BFEnorm) measured for milk protein containing no additives, milk powder containing ground calcium carbonate or surface-reacted calcium carbonate and milk powder containing the inventive anticaking agent.

[0284] FIG. 2: Normalized basic flow energy (BFEnorm) measured for milk powder containing no additives, milk powder containing ground calcium carbonate or surface-reacted calcium carbonate and milk powder containing the inventive anticaking agent.

[0285] FIG. 3: Areation ratio measured for milk protein containing no additives, milk powder containing ground calcium carbonate or surface-reacted calcium carbonate and milk powder containing the inventive anticaking agent.

[0286] FIG. 4: Areation ratio measured for milk powder containing no additives, milk powder containing ground calcium carbonate or surface-reacted calcium carbonate and milk powder containing the inventive anticaking agent.

[0287] FIG. 5: Caking crust analysis for a spice mix containing no additives, a spice mix containing ground calcium carbonate or surface-reacted calcium carbonate and a spice mix containing the inventive anticaking agent. The values on the y-axis correspond to the width of a peak in the total energy plot recorded by a rheometer, which is connected to the caking crust of the mix.

[0288] FIG. 6: Caking crust analysis measured for milk powder containing no additives, milk powder containing ground calcium carbonate or surface-reacted calcium carbonate and milk powder containing the inventive anticaking agent. The values on the y-axis correspond to the width of a peak in the total energy plot recorded by a rheometer, which connected to the caking crust of the powder.

EXAMPLES

1. Materials

[0289] Calcium Carbonate Materials:

[0290] GCC 1: Natural ground calcium carbonate; marble, from Kemalpasa, Turkey; volume-based particle size distribution d50=2.2 μm, d98=10 μm; specific surface area=1.4 m2/g.

[0291] GCC 2: Natural ground calcium carbonate; marble from Arizona, USA; volume-based particle size distribution d50=2.2 μm, d98=9 μm; specific surface area=1.3 m2/g.

[0292] SRCC: Surface-reacted calcium carbonate (SRCC) (d50 (vol)=5.1 μm, d98 (vol)=9.2 μm, specific surface area=96.1 m2/g with an intra-particle intruded specific pore volume of 1.588 cm3/g (for the pore diameter range of 0.004 to 0.4 μm).

[0293] Preparation of the SRCC:

[0294] In a mixing vessel, 10 liters of an aqueous suspension of ground limestone calcium carbonate was prepared by adjusting the solids of a ground limestone calcium carbonate having a particle size distribution of 90 wt.-% below 2 μm, based on the total weight of the ground calcium carbonate, such that a solids content of 15 wt.-%, based on the total weight of the aqueous suspension, is obtained. Whilst mixing the slurry, 2.8 kg phosphoric acid was added in form of an aqueous solution containing 30 wt.-% phosphoric acid to said suspension over a period of 10 minutes. Throughout the whole experiment the temperature of the suspension was maintained at 70° C. After the addition of the acid, the suspension was stirred for additional 5 minutes before removing it from the vessel and drying.

[0295] Inventive Calcium Carbonate-Based Composition (CCC):

[0296] Mixture of ground calcium carbonate and surface-reacted calcium carbonate in a ratio of 70:30.

[0297] The ground calcium carbonate used for the inventive calcium carbonate-based composition was GCC2 having a volume-based particle size distribution d50=2.2 μm, d98=9 μm; specific surface area=1.3 m2/g.

[0298] The surface-reacted calcium carbonate used for the inventive calcium carbonate-based composition was SRCC having a volume-based particle size distribution d50=5.1 μm, d98=9.2 μm; specific surface area=96.1 m2/g.

[0299] Base Component:

[0300] Milk powder: obtained from Hochdorf, Switzerland with volume-based particle size d50 of 61 μm.

[0301] Milk protein: obtained from Hochdorf, Switzerland with volume-based particle size d50 of 46 μm.

2. Methods

[0302] Basic Flowability Energy (BFE) and Normalized Basic Flowability Energy (BFE.sub.norm):

[0303] The basic flowability energy (BFE) is calculated from the work done in moving the blade through the tested powder composition from the top of a vessel to its bottom, i.e. during the downward traverse. To minimize the effect of the bulk density the BFE is normalized to the mass of the powder in a given volume. The instrument which was used to determine the BFE and BFEnorm was an FT4 Powder Rheometer (Freeman Technology Ltd). The accessories of the instrument such as blades can be rotated and simultaneously moved axially into a powder sample whilst axial force and rotational force are measured. A number of control modes are available on both axis including velocity, force and torque. In the standard dynamic tests, aeration testing are automated with no operator involvement apart from sample preparation. Dynamic testing used a 48 mm dia blade and a 160 ml powder sample contained in a 50 mm borosilicate test vessel. All samples for dynamic testing were pre-conditioned using the instruments ‘conditioning’ methodology. The ‘conditioning’ blade action gently disturbs the powder bed and creates a uniform, lightly packed test sample that can be readily and consistently reproduced. The force and torque measured during the downward movement of blade gives the Basic flow energy of powder. The BFE was measured with the standard program of the FT4 powder rheometer with the following conditioning cycle and test cycle. Down traverse conditioning: 5° (helix angle), −60 mm/s (tip speed); up traverse conditioning: −5° (helix angle), 60 mm/s (tip speed). Test: −5° (helix angle), −100 mm/s (tip speed).

[0304] Areation Testing and Aeration Ratio:

[0305] For the aeration testing the aeration program of Freeman FT4 powder rheometer was used. For the aeration testing, air is introduced into the base of the powder column. It is subsequently determined how the introduction of air changes the flow properties by measuring the reduction in basic flow energy. The aeration testing is performed with an air velocity of 18 mm/sec. The areation ratio is the ratio of BFE (in absence of air) to BFE with the 18 mm/sec of air flow in the powder composition. The areation ratio is inversely proportional to cohesivity of the powder composition. The aeration ratio was calculated using a method of the FT4 powder rheometer the following conditioning cycle and test cycle. Down traverse conditioning: 5° (helix angle), −60 mm/s (tip speed); up traverse conditioning: 20° (helix angle), 60 mm/s (tip speed). Test: −5° (helix angle), −100 mm/s (tip speed).

[0306] Caking Tests:

[0307] An FT4 Powder Rheometer® (Freeman Technology) was used to evaluate the rheological behavior of powder compositions by measuring the flow energy of the samples before and after caking to quantify the resistance to flow. All samples were conditioned prior to being subjected to a relative humidity of RH 75%. Samples were placed in a 25 mm×25 ml cylindrical vessel and conditioned, using a powder rheometer, by passing a specially shaped blade through the powder in a prescribed manner. This creates a stable, uniform and a repeatable stress state within the sample. Excess material was removed to generate a 25 ml test sample which was then stored in a constant 75% RH environment for 48 hours (for milk powder) or 144 hours (for a spice mix) to induce caking of the powder. The fixed relative humidity of 75% was maintained in the desiccator by use of a saturated sodium chloride solution. The caking creates a crust on top of the samples which results in the appearance of a peak in the total energy plot recorded by the rheometer. The powder caking was quantified by analyzing the peaks width which correspond to the depth of the caking crust. The more caking is occurring in the powder the broader the peak becomes. Thus, a higher value of peak width indicates more caking, whereas a lower value of peak width indicates less caking.

[0308] The caking tests were performed using a method of the FT4 powder rheometer with the following conditioning cycle and test cycle. Down traverse conditioning: 5° (helix angle), −40 mm/s (tip speed); up traverse conditioning: 5° (helix angle), 40 mm/s (tip speed). Test: −5° (helix angle), −100 mm/s (tip speed).

3. Results

[0309] FIG. 1 shows BFEnorm values measured with milk protein as a base component. The BFEnorm was measured for milk protein, which 1) does not contain an anticaking agent, 2) contains 1.0 wt % of GGC2 based on the total weight of the particulate composition, 3) contains 1.0 wt % of SRCC based on the total weight of the particulate composition, and 4) contains 1.0 wt % of the inventive calcium carbonate-based composition, based on the total weight of the particulate composition.

[0310] FIG. 2 shows the BFEnorm values measured with milk powder as base component. In this series of experiments 1.0 wt % of GCC1, based on the total weight of the particulate composition, was used as a comparative example instead of GCC2.

[0311] It can be gathered from FIGS. 1 and 2 that the inventive calcium carbonate-based composition significantly lowers the BFEnorm value of a base component, i.e. the milk powder or milk protein, when added to the base component. Thus, the inventive composition has a strong anticaking effect and/or flow improvement effect on the base component. Furthermore, FIGS. 1 and 2 show that the inventive calcium carbonate-based composition has a better anticaking effect and/or flow improvement effect than ground calcium carbonate or surface-reacted calcium carbonate alone as indicated by the lower BFEnorm value for the composition including the inventive anticaking agent and the base component. Thus, there is a synergistic effect for the mixture of GCC/SRCC compared to GCC or SRCC alone, which is particularly remarkable and surprising.

[0312] FIG. 3 shows aeration ratio values measured with milk protein as a base component. The aeration ratio was measured for milk protein, which 1) does not contain an anticaking agent, 2) contains 1.0 wt % of GGC1 based on the total weight of the particulate composition, 3) contains 1.0 wt % of SRCC based on the total weight of the particulate composition, and 4) contains 1.0 wt % of the inventive calcium carbonate-based composition, based on the total weight of the particulate composition.

[0313] FIG. 4 shows aeration values measured in the same way, but with milk powder as base component. In this series of experiments 1.0 wt % of GCC2, based on the total weight of the particulate composition, was used as a comparative example instead of GCC1.

[0314] It can be gathered from FIGS. 3 and 4 that the inventive calcium carbonate-based composition significantly increases the aeration ratio of a base component, i.e. the milk powder or milk protein, when added to the base component. Thus, the inventive composition has a strong anticaking effect and/or flow improvement effect on the base component. Furthermore, FIGS. 3 and 4 show that the inventive calcium carbonate-based composition has a better anticaking effect and/or flow improvement effect than ground calcium carbonate or surface-reacted calcium carbonate alone as indicated by the higher aeration ratio value for the composition including the inventive anticaking agent and the base component. Thus, there is a synergistic effect for the mixture of GCC/SRCC compared to GCC or SRCC alone, which is particularly remarkable and surprising.

[0315] FIG. 5 shows peak width values measured as described above with a spice mix as a base component. The peak width was measured for a spice mix, which 1) does not contain an anticaking agent, 2) contains 1 wt % of GGC1 based on the total weight of the particulate composition, 3) contains 1 wt % of SRCC based on the total weight of the particulate composition, and 4) contains 1 wt % of the inventive calcium carbonate-based composition, based on the total weight of the particulate composition. As described above, the peak width measured for a sample correlates with the caking crust depth.

[0316] FIG. 6 shows peak width values measured in the same way, but with milk powder as base component.

[0317] It can be gathered from FIGS. 5 and 6 that the inventive calcium carbonate-based composition significantly decrease the peak width values of a base component, i.e. the milk powder or spice mix, when added to the base component. Thus, the inventive composition has a strong anticaking effect and/or flow improvement effect on the base component. Furthermore, FIGS. 5 and 6 show that the inventive calcium carbonate-based composition has a better anticaking effect and/or flow improvement effect than ground calcium carbonate or surface-reacted calcium carbonate alone as indicated by the lower peak depth values for the composition including the inventive anticaking agent and the base component. Thus, there is a synergistic effect for the mixture of GCC/SRCC compared to GCC or SRCC alone, which is particularly remarkable and surprising.