Regulation 3.2 AUSTRALIA PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR AN INNOVATION PATENT ORIGINAL Name of Applicant: Fonterra Co-operative Group Linited Name of Inventor: Paul Desmond Signal Address for service in Australia: A J PARK, Level 11, 60 Marcus Clarke Street, Canberra ACT 2601, Australia Invention Title: A Method for Processing a Dairy Powder, such as a Milk Powder, by Compression, such as Roll Compaction, followed by Milling The following statement is a full description of this invention, inducing the best method of performing it known to us. 2203368 LDOC Regulation 3.2 AUSTRALIA PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR AN INNOVATION PATENT ORIGINAL Name of Applicant: Fonterra Co-operative Group Limited Name of Inventor: Paul Desmond Signal Address for service in Australia: A J PARK, Level 11, 60 Marcus Clarke Street, Canberra ACT 2601, Australia Invention Title: A Method for Processing a Dairy Powder, such as a Milk Powder, by Compression, such as Roll Compaction, followed by Milling The following statement is a full description of this invention, including the best method of performing it known to us. 2203368 IDOC I A Method for Processing a Dairy Powder, such as a Milk Powder, by Compression, such as Roll Compaction, followed by Miffing FIELD OF INVENTION 5 [0001] The present invention relates to a method for processing dairy powders, particularly to methods for producing powders having particle sizes within one or more specified ranges. The powders can be processed under conditions that give rise to altered characteristics. 10 BACKGROUND [0002] Spray-drying is a common form of producing powders. Dairy powders for example are typically spray-dried. Spray-drying gives rise to particle characteristics, such as 15 particle shape, size and porosity which are all properties of the concentrate conditions, atomisation conditions and drying conditions. Attempting to control the characteristics of spray-dried powders has been done in the past, and generally relates to altering the concentrate, atomisation or drying conditions under which the powder is processed. Sometimes other ingredients are added, such as solubilising agents to coat the particles and 20 improve solubility. These methods tend to be imprecise, and still result in a broad particle size distribution. The ability of these techniques to control the characteristics of the powder is limited. [0003] It is an object of at least preferred embodiments of the present invention to 25 provide a method that is suitable for controlling the particle size range of a powder, altering at least one characteristic of a powder, or that at least provides the public with a useful choice. SUMMARY OF INVENTION 30 [0004] A first aspect of the present invention relates to a method of processing a dairy powder, the method comprising, consisting of or consisting essentially of 2202096 1.DOC 2 subjecting a dairy powder to a compression step at a treatment pressure to produce a compressed dairy powder, and subjecting the compressed dairy powder to a milling step. 5 [0005] A second aspect of the present invention relates to a method of altering at least one characteristic of a dairy powder, the method comprising, consisting of or consisting essentially of subjecting a dairy powder to a compression step at a treatment pressure to produce a compressed dairy powder, and 10 subjecting the compressed dairy powder to a milling step to produce a powder having at least one altered characteristic selected from bulk density, flowability, dustiness, dispersibility, wettability, hydration viscosity, rate of hydration, rate of dissolution, solubility, sedimentation, suspension stability, blendability or caking properties. 15 [0006] Another aspect of the invention relates to a powder produced by a method of the invention. [0007] All of the following embodiments and preferred statements may relate alone or in 20 combination to the above aspects. [0008] In a preferred embodiment the compressed and milled powder is subjected to a screening step. 25 [0009] Preferably the method produces a powder having particle sizes within one or more specified ranges. Preferably at least about 90%, more preferably at least about 95%, most preferably at least about 99% of the particles of the powder have sizes within the specified range(s). 30 [0010] Preferably at least one specified range is about 0.1 micrometers to about 5 millimetres, mote preferably about 10 micrometers to about 1 millimetre. [0011J For some applications the powder may have a substantially uniform particle size 2202096IDOC 3 [0012] The method may produce a powder having particle sizes within one specified range. Alternatively the method may produce a powder having particle sizes within two or more specified ranges. That is, some of the particles of the powder will have a size within a 5 first specified range, and other particles of the powder will have a size within a second specified range, and so on. [0013] The compression step may be achieved by any suitable method, such as compaction or tableting for example. Preferably the compression step is achieved by roll 10 compaction. [0014] The processing conditions during roll compaction may be varied so as to affect the size range of particles in the powder, or the characteristics of the powder, or both. These conditions include: 15 Using or not using feed screws to feed powder between two counter-rotating rollers. " Speed of the feed screws when used. " The choice and level of vacuum applied to any feed screws " Varying the speed of the rollers, preferably anywhere from about 1 rpm to about 20 50rpm. " Varying the pressure of the rollers, preferably anything from about 1 kN/cm to about 50 kN/cm " Varying the gap between the rollers, preferably anywhere from 0.1mm to 1 0mm 25 [0015] The milling is preferably achieved by a rotating mill. Any other suitable milling method known in the art may be used. [0016] Preferably the dairy powder is at least one dairy powder or a mixture of dairy powders. The mixture may be of dairy powders of the same type (e.g. whole milk 30 powders) or powders of different types (e.g. whole milk powders and skim milk powders). The dairy powder may also be a mixture of one or more dairy powders and one or more non-dairy powders for example. 2202096_1.DOC 4 [0017] Preferably the dairy powder is from a cow, sheep, goat, pig, buffalo, camel, yak, horse, donkey, llama or human source or mixtures thereof. [0018] Suitable dairy powders include milk powders, colostrum powders, powders of 5 fractions of milk, or powders of fractions of colostrum, for example. In a preferred embodiment the dairy powder may be selected from whole milk powder, skim milk powder, low fat milk powder, whole milk retentate powder, skim milk retentate powder, low fat milk retentate powder, buttermilk powder, ultrafiltered milk retentate powder, nilk protein concentrate (MPC), milk protein isolate (MPI), calcium depleted milk protein 10 concentrate (MPC), low fat milk protein concentrate (MPC), colostrum powder, a powder of colostrum fraction, colostrum protein concentrate (CPC), colostrum whey powder, a powder of an immunoglobulin fraction from colostrum, whey powder, whey protein isolate (WPI), whey protein concentrate (WPC), sweet whey powder, lactic acid whey powder, mineral acid whey powder, a powder of a composition derived from any milk or colostrum 15 processing stream, a powder of a composition derived from the retentate or permeate obtained by ultrafiltration or microfiltration of any milk or colostrum processing stream, or a powder of a composition derived from the breakthrough or adsorbed fraction obtained by chromatographic separation of any milk or colostrum processing stream, or a powder of a composition comprising a full or partial hydrolysate of any one or more of these 20 ingredients or any combination of two or more thereof. [0019] In a most preferred embodiment the dairy powder may be selected from calcium caseinate, milk protein concentrate, skim milk powder, or whole milk powder. 25 [0020] The term "comprising" as used in this specification means "consisting at least in part of". When interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner. 30 [0021] It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10) also incorporates reference to all rational numbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that 2202096_1 DOC 5 range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, all sub-ranges of all ranges expressly disclosed herein are hereby expressly disclosed. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly 5 stated in this application in a similar manner. [0022] This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or 10 features. Where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth. BRIEF DESCRIPTION OF THE DRAWINGS 15 [0023] Figure 1 is a graph showing the particle size distribution of a number of powders as described in Example 6. DETAILED DESCRIPTION 20 1. Powders [0024] The powder in the method of the present invention is preferably at least one dairy powder or a mixture of dairy powders including those described in the Dairy Processing 25 Handbook (Tetra Pak Processing Systems, Lund, Sweden, 1995). The mixture may be of dairy powders of the same type (e.g. whole milk powders) or powders of different types (e.g. whole milk powders and skim milk powders). The dairy powder may also be a mixture of one or more dairy powders and one or more non-dairy powders for example. 30 [0025] Non-dairy powders may include carbohydrate powders, protein powders, lipid powders or any combination of two or more thereof for example. Non-daliy powders may be from animal, plant or micro-organisms sources including bacteria or yeast for example. 22f20S1 Ioc 6 [0026] Preferably the dairy powder is from a cow, sheep, goat, pig, buffalo, camel, yak, horse, donkey, llama or human source or mixtures thereof. [0027] Suitable dairy powders include milk powders, colostrum powders, powders of 5 fractions of milk, or powders of fractions of colostrum, for example. In a preferred embodiment the dairy powder may be selected from whole milk powder, skim milk powder, low fat milk powder, whole milk retentate powder, skim milk retentate powder, low fat milk retentate powder, buttermilk powder, ultrafiltered milk retentate powder, milk protein concentrate (MPC), milk protein isolate (MPI), calcium depleted milk protein 10 concentrate (MPC), low fat milk protein concentrate (MPC), colostrum powder, a powder of colostrum fraction, colostrum protein concentrate (CPC), colostrum whey powder, a powder of an immunoglobulin fraction from colostrum, whey powder, whey protein isolate (WPI), whey protein concentrate (WPC), sweet whey powder, lactic acid whey powder, mineral acid whey powder, a powder of a composition derived from any milk or colostrun 15 processing stream, a powder of a composition derived from the retentate or permeate obtained by ultrafiltration or microfiltration of any milk or colostrum processing stream, or a powder of a composition derived from the breakthrough or adsorbed fraction obtained by chromatographic separation of any milk or colostrum processing stream, or a powder of a composition comprising a full or partial hydrolysate of any one or more of these 20 ingredients. [0028] In a most preferred embodiment the dairy powder may be selected from calcium caseinate, milk protein concentrate, skim milk powder, or whole milk powder. 25 [0029] The powder may have been prepared using any suitable methods known in the art such as by spray-drying, roll-drying and freeze-drying a liquid. 2. Compressing, milling and screening 30 [0030] The compression step in the method of the present invention may be achieved by any suitable method, such as compaction or tableting for example. Tableting of powdered milk is for example described in a Meiji patent WO 2006/004190, the contents of which are hereby incorporated in their entirety by reference. Compaction has been used in other 2202096 .oc 7 industries. For example, battery material is compacted to produce more dense material, so that the battery charge lasts longer than uncompressed material. In the pharmaceutical industry methods involving compaction then milling are used to ensure adequate dosage control in tablets and other medicines. 5 [0031] Preferably the compression step is achieved by toll compaction. The processing conditions during roll compaction may be varied so as to affect the size range of particles m the powder, or the characteristics of the powder, or both. These conditions include: Using or not using feed screws to feed powder between two counter-rotating 10 rollers. " Varying the speed of the feed screws when used. " Varying the speed of the rollers, preferably anywhere from about 1 rpm to about 50rpm. " The choice and level of vacuum applied to any speed screws. 15 - Varying the pressure of the rollers, preferably anything from about I kN/cm to about 50 kN/cm " Varying the gap between the rollers, preferably anywhere from 0.1mm to 10mm Roll compaction has been widely reported in the literature: For example the following online links provide further information on this procedure. 20 http://aiche.confex.com/~aichie/s06/.prelimninaryp2rogram/abstract 38067.htm http: / /www.cababstractsplus.org/abstracts /Ahstract.aspxAcNo=20043148302 25 Suitable roll compaction apparatus are available from Fitzpatrick Company of Elmhurst, Illinois 60126, USA, particularly that supplied under the brand name Chilsonator@, and the Roller Compactors manufactured by Alexanderwerk AG of Remscheld, Germany. [0032] The milling in the methods of the present invention is preferably achieved by a 30 rotating mill. Any other suitable milling method known in the art may be used. [00331 Milling generally results in a 'milled powder' that encompasses a desired particle size range. Various known methods of milling can be conducted by an art skilled worker, 22,096 IDOCC 8 including techniques such as crushing, communition, grinding, pulverising and trituration for example. [00341 Milling is usually followed by screening, also known as size fractionation. Screening 5 is a method of separating particles according to size alone. In this process, the desired size range is selected from the 'milled powder'. Particles which are too large ('overs') and particles which are too small ('fines') are recycled back to either the rollers or the mill. 3. Particle size distribution 10 [0035] There are two standard ways of measuring particle size distribution: 1. Sieving analysis. Powder is placed at the top of a stack of standard sieves. Individual particles which are larger than the sieve size are collected on each sieve. 2. Laser diffraction (typically 'Malvern' brand instrument or similar) which gives a 15 more discretised size analysis. [0036] Preferably the method of the present invention produces a powder having particle sizes within one or more specified ranges. Preferably at least about 9 0 /, more preferably at least about 95%, most preferably at least about 99 % of the particles of the powder have 20 sizes within the specified range(s). [0037] Preferably at least one specified range is about 0.1 micrometers to about 5 millimetres, more preferably about 10 micrometers to about 1 millimetre. 25 [0038] The difference between the lowest value in at least one specified range and the highest value in the particle size range is preferably about 200 micrometers, more preferably about 100 micrometers, most preferably about 50 micrometers. [0039] For some applications the powder may have a substantially uniform particle size. 30 [0040] The method may produce a powder having particle sizes within one specified range. Alternatively the method may produce a powder having particle sizes within two or more specified ranges. That is, some of the particles of the powder will have a size within a 2202096_IDOC 9 first specified range, and other particles of the powder will have a size within a second specified range, and so on. 4. Powder characteristics 5 [00411 The methods of the present invention can be used to alter at least one characteristic of a dairy powder selected from bulk density, flowability, dustiness, dispersibility, wettability, hydration viscosity, rate of hydration, rate of dissolution, solubility, sedimentation, suspension stability, blendability or caking properties. 10 [0042] Preferably the at least one characteristic is altered by about at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 50, 90, 95, 99,100, 150, 200, 250, 300, 350, 400, 450, 490, 495, 499, or 5000/o compared to a powder that has not been subjected to a method of the invention. 15 [0043] Altering the bulk density can be beneficial in a number of ways. Increased bulk density for example can mean less packaging and transport costs. [0044] Altering characteristics such as flowability and dustiness provide many benefits including cost and time. For example, altered (improved) flowability can mean reduced 20 reconstitution time, and altered (reduced) dustiness can mean improved health, safety and hygiene, less wasted powder during processing, less effort and handling required to process the powder. [0045] Altering hydration characteristics such as dispersibility, wettability, hydration 25 viscosity, rate of hydration, rate of dissolution, solubility, sedimentation or suspension stability for example can also improve cost and time. [0046] The inventor of this application has discovered that the characteristics of a powder may be altered by subjecting the powder to both compression and milling. Without 30 wanting to be bound by theory, the inventor believes that there is a link between the particle size distribution of a compressed and milled powder and the characteristics of that compressed and milled powder. 22020961.DOC 10 [00471 Therefore at least some characteristics of a powder may be altered by: 1. providing an unprocessed powder (such as a typical spray-dried dairy powder) 2. roll compacting and milling the powder using processing conditions so as to obtain a processed powder having a broad particle size range 5 3. screening the processed powder into smaller subsets of powders with different particle size ranges 4. testing each subset powder for the desired characteristic. [00481 Once the desired particle size range has been determined, further batches of 10 powder may be processed so that substantially all of the powder falls within the desired particle size range and thus possesses the desired characteristics. [0049] The compacting and milling conditions may be varied as discussed above to ensure consistent production of powder with he desired particle size range and therefore desired 15 characteristics. [0050] The invention consists in the foregoing and also envisages constructions of which the following gives examples only. 20 Examples Example 1 - Calcium caseinate [00511 Three calcium caseinate samples were produced using the methods described 25 below: (1) Control, (2) Test sample 1 and (2) Test sample 2. [0052] Production of control sample [0053] The control sample was provided by Fonterra Co-Operative Group Limited, New 30 Zealand and consists of spray-dried calcium caseinate made using standard manufacturing techniques known in the art. [0054] Production of test samples 1 and 2 2202096 .moc 11 [0055] Part of the control sample was taken and roll compacted, milled and screened under different conditions in accordance with the method of the invention. 5 100561 Testing methods [0057J Each sample was tested using the tests described below. Due to quarantine restrictions, test sample 2 could not be fully tested. 10 [0058] Particle size distribution: The particle size distribution of each sample was measured using a Malvern Mastersize and the standard Malvern particle size distribution test for caseinates and results reported for D (v, 0.5), D (v, 0.1), D (v, 0.9). [0059] Flowability: This test measures the time 50 grams of powder takes to get through a 15 vibrating funnel, having a 21mm diameter orifice. [0060] Blendability: This test assessed the powders visually by blending 10 g of sample with 20 g of fluro casein in a beaker with a teaspoon and visually observing the uniformity of blending. 20 [0061] Static electricity / bag empty: This test involves visually assessing 20 grams of powder in a small bag after shaking. The size and density of powder particles affect the tendency of a powder to form static electricity. This test also indicates the powder's dustiness, flowability and bag emptying characteristics. 25 [0062] Bulk density: A sample is compacted into a graduated cylinder using a mechanical tap density tester and then weighed to determine the bulk density. In this case 35 taps was used. 30 [0063] Dispersability rate: This test looked at the dispersability rate of each sample when added to water. 2202096_I.DOC 12 [0064] Suspension stability: Powder was added to water and the suspension stability measured. [0065] Viscosity: The viscosity of each powder was tested at 1 5 % total solids and at 20'C. 5 The calcium caseinate was first dispersed at 40'C water first and then the viscosity tested at 20"C. [0066] Hydration Viscosity: Hydration viscosity was tested using standard testing methods. 10 [0067] Heat Stability: Each powder was heated at varying temperatures and the change in the powder observed. [0068] Results and discussion 15 [0069] The table outlines the main results of the evaluations. 22020% DOC 13 Samples Test sample 1 Test sample 2 Control Tests Malvern Dry D(v,0.1) m 21 16 Malvern Dry D(v, 0.5) pm 272 41 Malvern Dry D (v, 0.9) pn 1167 105 Bulk Density g/ml (35 taps) 0.56 0.61 0.35 Flow (seconds) 6 23 Blendability Good Good (big particles) Powder retained in bag empty 1.5% 8.6% test (%) Dispersability Excellent Excellent Excellent Suspension stability (ml/50ml) 1.6 0.3 0.6 Viscosity (cp) 62-5 --- 87.5 Hydration viscosity (ep) 43 (1 min) 30 (1 min) 139 (1 mimn) 13 (3 min) 10 (3 min) 77 (3 min) 8 (5 min) 12 (5 min) 16 (5 inin) 8 (10 min) 12 (10 min) 9 (10 min) Heat stability Good Good Good [0070] In general the two test samples performed much better from a powder handling perspective compared to the control. The improved suspension stability may result in 22020961.DOC 14 advantages in that the product works better in formulations requiring stability (i.e. the powder does not all sink to the bottom). The lower hydration viscosity means that the powder has a faster reconstitution rate. 5 [0071] During the trials, it was noted that the reconstitution characteristics of a powder varied with particle size range of the powder. There appeared to be different properties associated with a 'fine' powder compared to a 'coarse' granular powder. [0072j Four batches of the calcium caseinate having the following particle size range were 10 selected: (1) Milling size 0.8 millimeters, no fractionation (2) Miling size 3.15 millimeters, no fractionation (3) Milling size 3.15 millimeters, size fractionation less than 1 millimeter (4) Milling size 3.15 millimeters, size fractionation of 0.5 millimeters to 1.0 15 millimeter [0073] Each batch was Mixed with water. Batch 4 exhibited the best reconstitution characteristics, followed by batch 3. Batches 2 and 1 exhibited heavy clumping and therefore poor reconstitution characteristics. 20 Example 2 - Other dairy powders [0074] Processing milk powders 25 [00751 Six dairy products were subjected to roll compaction followed by milling using the method of the invention. The following results were obtained: 2202096_ LDOC (-ICU)~' lcc)P- cc)J() C=) CD (s) D.S7 1'4qrfl-i r4 -4 A A A 3 0 9Z dGIS DOSt bArscT r ,I4TqcwiS norstndsnLsqI I C= (A',/A, %/) s 1 /09 4 pqnljoS I00 i I .TnloTD putioij3rq 0 0 (D~ov) miw x -pu l Aqrnjsuj b~c 666) xauSoulL Cl-) u opxopuso(uj 24 CLq Ca~~~~C spoP (n-4ma~xi .L.I~ t C- Cl Ic) C C -16 [0077] Dispersibility was measured on a scale from 1 to 7, 1 being excellent dispersibility and 7 being poor dispersibility. These results are similar to those expected with standard spray-dried skim milk powder and whole milk powder, as without agglomeration powders to not disperse in water very well. 5 [0078] Standard spray-dried powders would likely perform similarly to the powders in the wettability test. [0079] The SDP measurement at 25 0 C showed that powders in this test were within the 10 range that would be expected for standard spray-dried powders. A typical skim milk powder tests in the range B-C and a typical whole milk powder tests in the range C-E. [0080] The coffee sedimentation and hot sedimentation results were slightly higher than what expected for standard whole milk powder or skim milk powder (skim milk powder is 15 normally lower than whole milk powder). However, it would not be unusual to see results at this level. Example 3 - Other dairy powders 20 [0081] Processing milk powders [0082] Eight dairy products were subjected to roll compaction followed by milling following the method of the invention. 2202096 1.DOC (6) \0 rn C)en : ON DO (S.0)P aCIIS N- Do CN- Ln O 0N 04L 04 - e n en) C14 Cq (I -6666 oxpAT c sx r- 00 'C\ N N CD C) C> CNC '10 0D en C) Nl n C% 0ON Z4su-( lyp' "I CO C2' 0 N- 0 0 Cq 0= LO en sdu 01 4IRsUoI( 3anf "J n \0'00Z ' 000 oq 606-1 00 1- Cl ON e - e enr '0 e 0 n N-, 0 ~ ~ ~ ~ t 04 e n N ncu Ajisu ~ ~ ~ c OIpL n e n 04 V4 4 C CC CD Cq kr)
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(rILtn) D.S3 4UZ"'fPQ'S 00 00 0000 N N CllC1 (s) D.5 L2 Tq'
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4aM.NClC A A A A A DoSZ dCOS Tqui uojsindsng S A, %) £/o9 ApTqnlo5 InoloD pnnoi24cn3a Iq I;PU IOU % ~ q x~ p ~ ~ sujin CD C:) CD ~ spuooos (oxrpc AqTFqolJJ l ~ ~ U rt 19 [0084] Dispersibility was measured on a scale from 1 to 7, 1 being excellent dispersibility and 7 being poor dispersibility. These results are similar to those you would expect with standard spray-dried skin milk powder and whole milk powder, as without agglomeration powders do not disperse in water very well. 5 [00851 Standard spray-dried powders would likely perform similarly to the powders in the wettability test. [0086] The SDP measurement at 25'C showed that powders in this test were within the 10 range that would be expected for standard spray-dried powders. A typical skim milk powder tests in the range B-C and a typical whole milk powder tests in the range C-E. [0087] The coffee sedimentation and hot sedimentation results were slightly higher than that expected for standard whole milk powder or skim milk powder (skli milk powder is 15 normally lower than whole milk powder). However, it would not be unusual to see results at this level. Example 4 20 [0088] Skim milk powder Ihe following example provides details of one combination of equipment variables and operating parameters for use in the method of the invention: Equipment Variables Roll Speed (rpm) 9 Roll Pressure (psig) / Pounds / linear inch 1100 10,225 Vertical Screw Speed (rpm) 325 Horizontal Screw Speed (rpm) 23 Roll Gap: Idle | work load (rmm) 0.028 0.07 Vacuum Press. (inch of Hg) / ports used 7.5 1 Operating Parameters Rotor Speed (rpm) 1750 2202096 I.DOC 20 Blade Type 225 Knife Screen Size I Type 0.109 Round Example 5 - Other dairy powders 5 [0089] Control milk powders [0090] Seven dairy products were selected. These powders were produced using standard techniques known in the art. They were not subjected to roll compaction or 10 milling: (1) Calcium caseinate 1 from example 2 (without roll compaction or milling) (2) Protein concentrate from example 2 (without roll compaction or milling) (3) Skim milk powder from example 2 (without roll compaction or milling) (4) Second skim milk powder 15 (5) Whole milk powder from example 2 (without roll compaction or milling) (6) Second whole milk powder (7) F-WMP from example 2 (without roll compaction or milling) [0091] These powders had the following characteristics: 20 o a -S 4f4 r0 1 - Powder (4) 0.1 4.9 1 2202096 1.DOC 21 Powder (5) 0.1 - 1 - Powder (6) 0.1 - Powder (7) 0.1 - 1 Example 6 - Bulk density [0092] Comparison of powders from examples 2 and 3 5 Bulk density Example 2 Example 3 Original Final Inc.% Final Inc.% Ca Cste 0.35 0.61 74% 0.56 60% MPC85 0.43 0.62 44% 0.58 35% SMP 0.72 0.86 19% 0.82 14% WMP 0.57 0.7 23% 0.69 21% F-WMP 0.6 0.71 18% 0.68 13% Example7 - Particle size distribution 10 [0093] Malvern tests [0094] Five dairy powders were roll compacted and milled according to the method of the invention 15 10095] Powder characteristics [0096] Spray dried control samples are in brackets. Tests Calcium caseimate Calcium Sodium Sodium caseinate Caseinate 2202096 DOC 22 Sieve retained on 600 Sieve retained on 0 <0.1% (0.1) <0.1 () <0.1% (0.1) Sieve retained on 150 45% (2.1%) 27.9% (3.39%) 42% (6/,) Bulk density g/mL (35 0.58 (0.34) 0.59 (0.42) 0.625 (0.56) taps) Flow (seconds) 9 (30) 9 (11) 2 (4) Blendability Good Good Good Dispersibility Excellent Excellent Not tested Suspension stability 1.9 (0.8) 1.8 (4.0) Not tested [0097] The particle size distribution of each sample was measured and is shown in Figure 1. 5 INDUSTRIAL APPLICATION [0098] The powders produced by the method of the present invention may be used in any commercial application of dairy powders including the dairy and food industries. 10 [0099] Those persons skilled in the art will understand that the above description is provided by way of illustration only and that the invention is not limited thereto. 22020961,DOC