Process for demineralizing a milk protein composition and milk protein composition obtained thereby

Abstract

A process for demineralizing a milk protein composition and a milk protein composition obtained by said process, comprising: step (ii) electrodialyzing a milk protein composition (MPC) on an electrodialyzer (5), the unit cell (15) having three compartments (20, 26, 30) for converting at least one cation in the milk protein composition (MPC) into at least one hydrogen ion H + to obtain an at least partially demineralized and acidified milk protein composition (MPC1); and step (iii) of electrodialyzing the milk protein composition (MPC1) obtained in step (ii) in an electrodialysis device (10), the device having a unit cell (35) with three compartments (39, 43, 47) and configured to convert at least one anion in the milk protein composition (MPC1) into at least one hydroxyl ion OH. - and a demineralized milk protein composition (MPC2) obtained by said process.

Description

[Technical field]

[0001] The present invention relates to a process for demineralizing a milk protein composition and to the milk protein composition obtainable by this process, in particular demineralized whey. [Background technology]

[0002] The milk protein composition may be whey, which is the liquid fraction obtained from the coagulation of milk. A distinction is made between two types of whey: whey obtained from the manufacture of casein or fresh cheese in an acid medium (acid whey) and whey obtained from the manufacture of casein with rennet, when cooked or semi-cooked cheese is pressed (sweet whey).

[0003] Whey is composed mainly of water, lactose, proteins (especially serum proteins), and minerals. Separation of both lactose and proteins can increase the value of whey. Whey proteins can also be used as ingredients in infant formulas. Demineralized whey, especially lactose, can be used in the manufacture of confectionery, cakes, ice cream, deli foods, pastries, etc.

[0004] Whey can be demineralized by electrodialysis and / or passage through cation and anion exchange resins, via a nanofiltration step, to achieve demineralization rates of 70 to 90%, and in fact even higher.

[0005] However, ion exchange resins generate a large amount of wastewater containing salts, which makes treatment difficult and costly.

[0006] At the same time, consumers are increasingly demanding raw materials from the food processing industry that retain their initial natural properties and are not altered and / or denatured, or in any case as nearly intact as possible. In addition, there is a demand for dairy demineralization processes that limit or eliminate the presence of exogenous mineral species. In fact, ion exchange resins work by exchanging mineral species in the composition to be treated with exogenous mineral species. However, the elimination of one or more passages of ion exchange resins makes it difficult to produce milk protein compositions that are highly demineralized (e.g. demineralized to 70%, 80% or 90%). If the demineralization is taken over by other processing systems, there is a risk that the membranes of these systems will clog faster due to the high mineral load.

[0007] US Patent No. 4,971,701 describes a process for demineralizing whey that involves the simultaneous extraction of positively and negatively charged ions via electrolysis techniques. This process should not be confused with three-compartment electrodialysis, which is designed to allow for the displacement of cations or anions, rather than the simultaneous extraction of cations and anions. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Pat. No. 4,971,701 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention aims to propose a process for demineralizing milk protein compositions without the use of (anionic and / or cationic) ion exchange resins.

[0010] The present invention also aims to propose a process for demineralizing a milk protein composition, which limits or eliminates the introduction of exogenous mineral compounds into the milk protein composition. [Means for solving the problem]

[0011] DISCLOSURE OF THEINVENTION According to a first aspect, the present invention comprises the steps of: (i) providing a milk protein composition; (ii) electrodialysing the milk protein composition in an electrodialysis device, the unit cell of the device having three compartments and converting at least one cation in the milk protein composition into at least one hydrogen ion H + to obtain an at least partially demineralized and acidified milk protein composition; (iii) electrodialysing the milk protein composition obtained in step (ii) in an electrodialysis device, the unit cell of the device having three compartments and converting at least one anion in the milk protein composition into at least one hydroxyl ion OH - and replacing the (iv) obtaining a demineralized milk protein composition The above problems are overcome by the subject matter of a process for the production of a demineralized milk protein composition, characterized in that it comprises:

[0012] In general, in electrodialysis, dissolved and ionized mineral or organic species, such as salts, acids, and bases, are transported through an ionic membrane under the action of an electric current. The electrodialysis device may comprise parallel and alternating cationic (cation-permeable) membranes (MECs) and / or anionic (anion-permeable) membranes (MEAs). Under the action of an electric field applied by the anode and the cathode, the MECs block the anions and allow the cations to pass, and the MEAs block the cations and allow the anions to pass. In this way, a concentrating compartment (concentration) and a desalting compartment are created. This most common type of electrodialysis is the electrodialysis whose basic unit cell comprises two compartments. This unit cell corresponds to a minimally repeated pattern of concentrating and desalting operations (one compartment corresponds to one concentration or desalting). The solution is renewed in the compartments by circulation parallel to the plane of the membrane. The application of the electric current is carried out by two electrodes, parallel to the plane of the membrane and placed at either end of the electrodialysis device.

[0013] Advantageously, in the present invention, in a novel manner, the electrodialysis device has three compartments and further allows the exchange of ions: the electrodialysis devices of steps ii) and iii) therefore comprise, in addition to the desalting compartment (where ions are lost) and the concentrating compartment (where ions accumulate), a conversion compartment for cations in the case of step ii) and for anions in the case of step iii).

[0014] The milk protein composition (MPC) obtained in step ii) is depleted of cations and acidified (pH decrease), whereas the milk protein composition obtained in step iii) is depleted of anions (pH increase). By combining steps ii) and iii), a cationic demineralization can be followed by an anionic demineralization, these steps ii) and iii) corresponding to cationic and anionic substitution, respectively. The resulting demineralization can be strong, reaching demineralization rates of 70% or more, in particular 75% or more, 80% or more, even 85% or more, in particular 90% or more.

[0015] Advantageously, the process according to the invention is less polluting since it does not generate regeneration effluents to be treated and does not consume exogenous acids and bases or, according to the following different variants, consumes very little of them, making the process eco-efficient.

[0016] The milk protein composition obtained in step ii) has an acidic pH, in particular below the isoelectric point of the proteins (in particular serum proteins) of the MPC in step i), in particular below 6, preferably below 4.

[0017] This condition helps control the microbiological stability. Furthermore, the dairy protein composition can be heat treated at different temperatures and durations than those applied in a non-acidic environment, limiting protein denaturation and thus advantageously reducing dairy protein degradation.

[0018] Advantageously, in particular by increasing the pH in step iii) so as to be equal to or greater than the pKa of at least one organic acid of the treated composition, it is possible to obtain the anionic form of said organic acid, so that it can be extracted through the anionic membrane in step iii).

[0019] Preferably, the temperature of the milk protein composition in step ii) and / or step iii) is below 40°C, in particular above 0°C.

[0020] After step iii), in particular in step iv), the milk protein composition has a pH of 6 or more, in particular 6.2 or more, more particularly 8 or less.

[0021] (Milk protein composition) Preferably, the milk protein composition is selected from whey, e.g. sweet whey or acid whey, or mixtures thereof; milk ultrafiltration permeate; milk microfiltration permeate; whey ultrafiltration retentate or permeate; ultrafiltration retentate or permeate of milk microfiltration permeate; or mixtures thereof (List I).

[0022] Preferably, the sweet and / or acid whey is raw, i.e. they have not undergone any manipulation to reduce their mineral load. Thus, whey not specifically mentioned may be raw or partially demineralized.

[0023] Sweet whey is preferably obtained by chemically treating milk, in particular with rennet, to recover both the casein and the sweet whey.

[0024] Acid whey is preferably obtained by acid treatment of milk, in particular with lactic acid and / or hydrochloric acid, to recover both the casein and the acid whey.

[0025] The crude or partially demineralized whey may be pre-concentrated mechanically (e.g. by reverse osmosis or nanofiltration or a combination thereof) or thermally (e.g. by evaporation). The crude acid whey and / or crude sweet whey and / or milk microfiltration permeate have a dry extract greater than 0% and not greater than about 6% (±10%). The crude whey and / or milk microfiltration permeate may undergo a concentration step as defined above to result in a dry extract greater than about 18% (±10%) and not greater than about 22% (±10%).

[0026] The milk protein composition according to the invention is liquid when in use. It can be obtained by reconstituting a liquid solution from a powder and / or liquid, in particular selected from list I above.

[0027] Preferably, the milk protein composition in step i) is partially demineralized, which reduces the size, i.e. the active membrane surface, of the three-compartment electrodialysis device in step ii) and / or step iii).

[0028] Preferably, the demineralization rate of the milk protein composition in step i) is at least 30%, more preferably at least 40%, preferentially at least 50%, particularly at least 60% and especially at most 70%.

[0029] Preferably, the milk protein composition obtained in step iv) has a demineralization rate of at least 70%, in particular at least 85%, more particularly at least 90% (DM90).

[0030] In one embodiment, the milk protein composition has a dry extract by mass of more than 1%, preferably equal to or greater than 5% and equal to or less than 10%, e.g., non-concentrated whey.

[0031] In another embodiment, the milk protein composition has a dry extract by mass of 10% or more and 30% or less, preferably 15% or more and 25% or less. It is, for example, concentrated whey. Concentration of the whey to dry matter can be carried out by reverse osmosis, nanofiltration or other thermal concentration methods.

[0032] In general, the milk protein composition may be obtained from any dairy female.

[0033] Preferably, the milk protein composition is obtained from milk selected from cow's milk, goat's milk, sheep's milk, donkey's milk, buffalo's milk, mare's milk or mixtures thereof, more preferably milk selected from cow's milk, goat's milk and sheep's milk or mixtures thereof, in particular cow's milk.

[0034] The protein composition comprises milk proteins, in particular serum proteins.

[0035] The whey contains serum proteins and is free of casein, which remains in the bulk (coagulated) portion during milk processing and / or in the milk microfiltration retentate.

[0036] Preferably, the crude sweet whey has one of the following characteristics, either alone or in combination: · pH must be between 5.8 and 6.5; the ratio of lactose by weight to the weight of the dry extract is greater than or equal to 70%, in particular greater than or equal to 74%; the ratio of protein by mass to the mass of the dry extract is greater than or equal to 10%, in particular greater than or equal to 12% and in particular less than or equal to 30%; The ratio of the mass of ash to the mass of dry matter is at least 8%, in particular at most 10%; and The ratio of the mass of organic acids to the mass of the dry extract is at least 2%, in particular at most 5%.

[0037] Preferably, the crude acid whey has one of the following characteristics, either alone or in combination: · pH below 5, especially below 4.5; In the case of whey obtained from the manufacture of cheese in an acid medium, the ratio of the mass of lactose to the mass of the dry extract is not less than 55%, in particular not more than 65%; In the case of whey obtained from the production of casein in an acid medium, the ratio of the mass of lactose to the mass of dry matter is greater than or equal to 70%, in particular less than or equal to 85%; the ratio of protein mass to dry matter mass is greater than or equal to 4%, in particular less than or equal to 12%; The ratio of the mass of ash to the mass of dry matter is at least 10%, in particular at most 15%; and In the case of whey obtained from the manufacture of cheese in a lactic acid medium, the ratio by weight of organic acids to the weight of the dry extract is greater than or equal to 10%, in particular less than or equal to 20%; In the case of whey obtained from the production of casein in an acid medium, the ratio by weight of organic acids to the weight of dry matter is at least 2% and in particular at most 5%.

[0038] Demineralization essentially consists in removing, in whole or in part, the ash present in the milk protein composition, and in particular in whey.

[0039] The ash content of the milk protein composition may be measured using standardized method NF V04-208 (October 1989), entitled "Milk - Determination of ash - Reference method."

[0040] In the present specification, dry extract by weight is understood to mean the dry mass of the milk protein composition obtained after evaporating the water, in particular at atmospheric pressure, until a stable total dry mass is obtained based on the total mass of the milk protein composition. Said dry extract by weight can be measured using the standardized method ISO 6731: January 2011, "Milk, cream, and unsweetened condensed milk - Determination of dry matter (Reference method)".

[0041] Preferably, the milk protein composition (or MPC) in step i) has a conductivity of at least 1 mS / cm, more preferably at least 3 mS / cm.

[0042] Preferably the MPC in step iv) has an ash content of not more than 2.5%, preferably not more than 1.5%, on a dry basis.

[0043] Preferably, the milk protein composition comprises the following cations: calcium, magnesium, sodium, potassium, which are in particular the cations that are subject to the demineralization process according to the invention.

[0044] Preferably, the milk protein composition comprises the following anions: chloride, phosphate, sulfate, lactate, acetate, and citrate, which are the anions that are particularly targeted in the demineralization process according to the present invention.

[0045] In one embodiment, the monovalent cations and monovalent anions are at least partially extracted from the MPC prior to step i) in a prior demineralization step comprising a nanofiltration or reverse osmosis step and in particular a two-compartment electrodialysis step applied to the nanofiltration retentate.

[0046] In a variant, the production process includes the step of: the salt obtained directly from the electrodialysis step ii), the salt obtained indirectly from the electrodialysis step ii), the salt obtained directly from the electrodialysis step iii), the salt obtained indirectly from step iii) of electrodialysis, salts from a prior demineralization step carried out on the milk protein composition in step i), A mixture of these (v) treating at least a portion of the salt selected from the group consisting of sodium chloride salts and / or potassium chloride salts (NaCl, KCl), The treating step (v) is configured to generate, on the one hand, one or more acids, preferably hydrochloric acid and / or sulfuric acid, from the salt, and, on the other hand, to generate one or more bases, preferably sodium hydroxide and / or potassium hydroxide, from the salt.

[0047] By said salt being obtained directly from steps ii) and / or iii) and / or i), it is understood that the latter has not undergone steps vi) or vii) defined below, in particular a nanofiltration step.

[0048] By a salt is indirectly obtained from steps ii) and / or iii) and / or i), it is understood that the latter has undergone steps vi) or vii) as defined below, in particular a nanofiltration step.

[0049] Said prior demineralization step consists / consists of a step of electrodialysis, in particular in a two-compartment electrodialysis device equipped with anionic and / or cationic permselective membranes, in which case the salts used in steps ii) and / or iii) are advantageously obtained at least in part from the milk protein composition itself.

[0050] The salts used in the process according to the invention are preferably selected from chlorides of monovalent cations; chlorides of divalent cations; in particular sodium chloride, potassium chloride, calcium chloride; sulfates of monovalent cations, sulfates of divalent cations; in particular sodium sulfate, potassium sulfate, calcium sulfate; phosphates of monovalent cations, phosphates of divalent cations; in particular sodium phosphate, potassium phosphate, calcium phosphate, and mixtures thereof.

[0051] Preferably, step ii) (in particular the cationic displacement) comprises circulating said milk protein composition between two cationic membranes, in particular the compartment through which said milk protein composition circulates is defined between two cationic membranes.

[0052] Preferably, step iii) (in particular the anionic displacement) comprises circulating said milk protein composition between two anionic membranes, in particular the compartment through which said milk protein composition circulates is defined between two anionic membranes.

[0053] In a variant, said treating step (v) consists of an electrodialysis step carried out in a bipolar membrane electrodialysis device.

[0054] A bipolar membrane consists of a cation exchange layer and an anion exchange layer separated by a hydrophilic junction.

[0055] In a variant, in step (v), the bipolar membrane electrodialysis device comprises a unit cell having three compartments A, B and C, compartments A and B being supplied with water and compartment C, located between compartments A and B, being supplied with one or more salts, in particular sodium chloride salts and / or potassium chloride salts (NaCl and / or KCl).

[0056] In one embodiment, each unit cell of the electrodialysis apparatus in step v) comprises a first compartment defined between a bipolar membrane and an anionic membrane, a second compartment defined between an anionic membrane and a cationic membrane, and a third compartment defined between a cationic membrane and a bipolar membrane.

[0057] Preferably, the first compartment and the third compartment are supplied with water and a second compartment disposed between the first and third compartment is supplied with salt.

[0058] Advantageously, in step v), in particular in the bipolar membrane electrodialysis step v), acids (in particular hydrochloric acid and / or sulphuric acid) and bases (in particular sodium hydroxide and / or potassium hydroxide) are produced from the salt flows resulting from steps ii) and / or iii), in particular from the respective first or third compartment (depending on whether in steps ii) and / or iii) a selectively permeable membrane as defined below is used).

[0059] This configuration makes it possible to carry out steps ii) and / or iii) of electrodialysis with acid or basic salts from the milk protein composition itself, a process which makes it possible to eliminate or at least very significantly reduce the introduction of exogenous mineral compounds.

[0060] Said salts, in particular sodium chloride salts, may in part result from a prior demineralisation step, in particular a nanofiltration and / or electrodialysis (two compartment) step, applied to said milk protein composition in step i).

[0061] In a variant, at least a portion of the salts obtained in the treating step (v), in particular hydrochloric acid and / or sulphuric acid, is fed to one of the three compartments of the electrodialysis device in step ii).

[0062] In a variant, at least a portion of the salts obtained in the processing step (v), in particular sodium hydroxide and / or potassium hydroxide, is fed to one of the three compartments of the electrodialysis device in step iii).

[0063] In a variant, in the electrodialysis step ii) a mixture is produced comprising at least one chloride salt of a monovalent cation, such as a sodium chloride salt and / or a potassium chloride salt, and at least one chloride salt of a divalent cation, such as a calcium chloride (CaCl2) salt, said mixture undergoing a separation step (vi) of said chloride salt of a monovalent cation and said chloride salt of a divalent cation, in particular a nanofiltration step.

[0064] In a variant, the process according to the invention comprises a step of electrodialysis of the at least partially demineralized and acidified milk protein composition (MPC1) obtained in step ii) before step iii) in an electrodialysis device comprising a two-compartment unit cell. The electrodialysis device comprises a plurality of cells, for example at least five cells. In a first embodiment, the electrodialysis device comprises at least one unit cell having a first compartment defined between a cationic membrane and an anionic membrane and a second compartment defined between an anionic membrane (particularly that of the first compartment) and a cationic membrane (particularly that of the first compartment). Preferably, the first compartment is supplied with the partially demineralized and acidified milk protein composition (MPC1) obtained in step ii). Preferably, the second compartment is supplied with water.

[0065] This step advantageously makes it possible to extract both the anions and the cations in the MPC1.

[0066] This intermediate electrodialysis step, in particular between ESC (ii) and ESA (iii), makes it possible to reduce the size of the electrodialysis device (i.e. the number of cells) in step iii).

[0067] This intermediate two-compartment electrodialysis step, carried out between steps ii) and iii), also makes it possible to achieve cation and anion rejections of more than 90%.

[0068] An intermediate electrodialysis step in a two-compartment electrodialysis device may be carried out before or after the heat treatment step viii) described herein.

[0069] In a variant, said electrodialysis step iii) produces a mixture comprising at least one sodium salt of a monovalent anion and at least one sodium salt of a divalent anion, in particular sodium chloride (NaCl) and sodium phosphate, which mixture undergoes a separation step (vii) of said sodium salt of the monovalent anion and of said sodium salt of the divalent anion, in particular a nanofiltration step.

[0070] These steps vi) and / or vii) make it possible to complete the bipolar membrane electrodialysis by avoiding the precipitation of divalent cations (in particular calcium and / or magnesium) on the membranes, in particular on the cationic membrane of the bipolar electrodialysis of step v), in particular when steps ii) and iii) are carried out without a selectively permeable membrane.

[0071] In a variant, the salt of the monovalent cation, in particular the chloride salt of the monovalent cation, preferably sodium chloride, collected on completion of separation step (vi) and / or separation step (vii) is fed to the electrodialysis step ii) and / or to the electrodialysis step iii).

[0072] This configuration applies in particular when steps (ii) and (iii) are carried out with a permselective membrane as defined below.

[0073] In a variant, the salt of the monovalent cation, in particular the chloride salt of the monovalent cation, preferably sodium chloride, collected on completion of separation step (vi) and / or separation step (vii) is at least partially subjected to a treatment step (v).

[0074] This configuration applies in particular when steps (ii) and (iii) are carried out without a permselective membrane as defined below.

[0075] In a variant, the electrodialysis device in step ii) comprises at least one membrane having selective permeability for monovalent cations.

[0076] Thus, a membrane that is selectively permeable to monovalent cations (or monovalent anions) will allow only monovalent cations (or monovalent anions) to pass through, but will not allow anions (or cations) and cations (or anions) with a valence greater than one, particularly divalent, to pass through.

[0077] In a variant, the three-compartment unit cell of the electrodialysis device in step ii) comprises at least one unit cell, preferably each of said unit cells comprising: a first compartment defined between a membrane selectively permeable to monovalent cations and a cationic membrane; a second compartment defined between two cationic membranes; and a third compartment defined between the cationic membrane and a membrane having selective permeability to monovalent cations.

[0078] In another variant, the three-compartment unit cell of the electrodialysis device in step ii) comprises at least one unit cell, preferably each unit cell comprising: a first compartment defined between an anionic membrane and a cationic membrane; a second compartment defined between two cationic membranes; and a third compartment defined between the cationic membrane and the anionic membrane.

[0079] The cation exchange step (ii) may thus be carried out with or without a permselective membrane.

[0080] In a sub-variant (of the variant of step ii above), the first compartment is provided with at least one acid salt, preferably a hydrochloride salt, the second compartment is provided with the milk protein composition of step i) and the third compartment is provided with at least one chloride salt of a monovalent cation, preferably sodium.

[0081] In a variant, the electrodialysis device of step iii) comprises at least one membrane having a selective permeability for monovalent anions.

[0082] Thus, a membrane that is selectively permeable to monovalent anions will allow only monovalent anions to pass through, but not cations and anions with a valence higher than one, especially divalent, or cations and anions with a molecular weight of 90 or more (daltons, i.e. the sum of the atomic weights of the various atoms that make up the molecule).

[0083] In a variant, the three-compartment unit cell of the electrodialysis device of step iii) is composed of at least one unit cell, preferably each unit cell comprising: a first compartment defined between a membrane having selective permeability to monovalent anions and an anionic membrane; A second compartment separated between two anionic membranes; a third compartment defined between the anionic membrane and a membrane having selective permeability to monovalent anions;

[0084] In another variant, the three-compartment unit cell of the electrodialysis device in step iii) comprises at least one unit cell, preferably each unit cell comprising: a first compartment defined between a cationic membrane and an anionic membrane; a second compartment defined between two anionic membranes; and a third compartment defined between the anionic membrane and the cationic membrane.

[0085] The anionic displacement step (iii) may thus be carried out with or without a permselective membrane.

[0086] In a sub-variant (of the variant of step iii above), the first compartment is provided with at least one basic salt, preferably a sodium hydroxide salt, the second compartment is provided with the partially demineralized and acidified milk protein composition obtained in step ii) and the third compartment is provided with at least one chloride salt of a monovalent cation, preferably of sodium.

[0087] In a variant, the process comprises a heat treatment step (viii) carried out after step (ii) and before step (iii).

[0088] Preferably, in this step (viii), the milk protein composition has a temperature of at least 70°C and at most 110°C for a period of at least 5 seconds and at most 10 minutes.

[0089] The acidic medium of the dairy protein composition aids in the elimination of bacteria, including those that are more difficult to destroy, such as spore germs.

[0090] In a variant, said milk protein composition in step i) is whey, in particular originating from organic agriculture.

[0091] In a variant, the milk protein composition in step i) is partially demineralized whey, in particular having undergone at least one step selected from an electrodialysis step, a nanofiltration step, a reverse osmosis step, an evaporation step, and combinations thereof.

[0092] These steps also concentrate the MPC, i.e. increase the mass of its dry extract.

[0093] The subject of the present invention relates, according to a second aspect, to a demineralized milk protein composition obtainable by a production process according to any of the embodiment variants defined with reference to the first aspect of the invention. [Brief description of the drawings]

[0094] [Figure 1] FIG. 1 is a schematic representation of the various steps of a first example process for producing a demineralized milk protein composition. [Diagram 2] FIG. 4 is a schematic representation of a unit cell of a bipolar membrane electrodialysis device implemented in an example of the process step v) according to the invention, in particular in the first and second example processes shown in FIGS. 1 and 3. [Diagram 3] FIG. 1 is a schematic representation of the various steps of a second example process for producing a demineralized milk protein composition. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0095] (Description of the embodiment) A first example of a process for producing a demineralized milk protein composition, shown in Figure 1, comprises two electrodialysis devices 5, 10, whose unit cells 15, 35 have three compartments. In Figure 1, a single unit cell 15 of the electrodialysis device 5 is shown. This unit cell 15 comprises a first compartment 20 defined between the cationic permselective membrane 22 and the cationic membrane 24, a second compartment 26 defined between the cationic membrane 24 and the cationic membrane 28, and a third compartment 30 defined between the cationic membrane 28 and the cationic permselective membrane 32. In Figure 1, a single unit cell 35 of the electrodialysis device 10 is shown. The unit cell 35 comprises a first compartment 39 defined between the anionic permselective membrane 37 and the anionic membrane 41, a second compartment 43 defined between the anionic membrane 41 and the anionic membrane 45, and a third compartment 47 defined between the anionic membrane 45 and the anionic permselective membrane 49. The cationic permselective membranes 22 and 32 allow only monovalent cations to pass, and the permselective membranes 37 and 49 allow only monovalent anions to pass. The electrodialysis devices 5 and 10 each comprise a cathode (80, 88) and an anode (78, 90) for generating an electric current through a conductive solution passing through the compartments of the unit cells 15 and 35. The process also comprises a first nanofiltration device 50 for carrying out step vi), a second nanofiltration device 60 for carrying out step vii), and a three-compartment bipolar membrane electrodialysis device 70 for carrying out step v), as detailed in FIG. 2. This first example process also includes a heat treatment device 75 for carrying out the heat treatment step viii).

[0096] In operation, a milk protein composition MPC, in particular whey demineralized to at least 50%, is fed in step i) and then fed to the second compartment 26 of the electrodialysis device 5. At the same time, an acidified salt, in particular a hydrochloric acid solution, is fed to the first compartment 20 and a brine, in particular a sodium chloride salt, is fed to the third compartment 30. +The ions pass through the cationic membrane 24 and enter the third compartment 30, + ions and pass through the selectively permeable membrane 32 or the selectively permeable membrane 22 under the influence of an electric field. + ions and Ca 2+ The ions pass through the cationic membrane 28 in the direction of the cathode 80 under the influence of an electric field, and the H + ions. In this way, the milk protein composition of MPC1 obtained in step i) is partially demineralized and the cations are replaced by H + The pH of MPC1 is below 4. The third compartment 30 contains a mixture of chloride salts, in particular calcium chloride salt (CaCl2) and sodium chloride salt (NaCl), derived from the milk protein composition MPC. In this way, monovalent ions (e.g., Na + ;K + ) is supplied to the first compartment 20 through the cationic permselective membrane 22 or the cationic permselective membrane 32, while divalent ions (e.g., Ca 2+ ) remains in the third compartment 30.

[0097] The acidified milk protein composition MPC1 is subjected to a heat treatment in step viii) (90°C for a few minutes) in order to improve its bacteriological stability. Advantageously, since composition MPC1 is acidified, the heat treatment conditions can be specified to be more severe than usual so as not to alter the proteins.

[0098] The mixture of salts originating from the third compartment 30 may be subjected to a nanofiltration step vi) in a nanofiltration unit 50 in order to increase the purity of the sodium chloride salt originating from the third compartment 30 by retention of divalent salts such as calcium chloride CaCl2. The sodium chloride salt thus purified is fed to the third compartment 30.

[0099] In particular, the pasteurized composition MPC1 undergoes a second electrodialysis step iii) in the electrodialysis device 10. The first compartment 39 is provided with a basic salt, such as sodium hydroxide, from step v). OH - The mobility of the ions is Cl - The mobility of the ions is larger than that of the OH - The ions pass through the anionic membrane 41 and are separated from the Cl ions which originate from the first compartment 39 and pass through the anionic permselective membrane 49 or 37 under the influence of the electric field. - In the second compartment 43, which is supplied with the heat-treated and acidified composition MPC1, the remaining anions (chloride, sulfate, phosphate) pass through the anionic membrane 45 under the influence of an electric field in the direction of the anode 90, replacing the OH ions from the first compartment 39. - ions. Thus, the composition MPC2 obtained in step iv) is demineralized and deacidified. In the third compartment 47, a mixture of sodium and potassium chloride salts (NaCl, KCl) and phosphate is obtained from MPC1. The chloride ions pass through the anion-selective membrane 49 and are provided in the first compartment 39, while the divalent ions, in particular the phosphate ions, are blocked in the third compartment 47 by the anion-selective membrane 49.

[0100] The salt emerging from the third compartment 47 may undergo a nanofiltration step vii) in order to increase the purity of the sodium chloride salt emerging from the third compartment 47 by retention of the phosphate ions.

[0101] This first example process also comprises a step v) of treating sodium chloride salts in a three-compartment bipolar membrane electrodialysis unit 70, allowing the regeneration of acids (mainly HCl) and bases (mainly sodium hydroxide) from the NaCl streams originating from the first compartments 20 and 39 of the cation and anion electrodialysis steps ii) and iii) and optionally from NaCl originating from a prior demineralization step carried out upstream on the composition MPC of step i) and / or from food-grade NaCl. Said prior demineralization step preferably consists of a nanofiltration step followed by a two-compartment electrodialysis step applied to the nanofiltration retentate. With the exception of the salts used at the start of step v), the acid and base salts used to carry out the electrodialysis steps ii) and iii) originate from the milk protein composition MPC1, thereby avoiding the introduction of exogenous mineral compounds.

[0102] 2 shows an electrodialysis device 70 and its unit cell 105, which comprises a first compartment 110 defined between a bipolar membrane 112 and an anionic membrane 114, a second compartment 116 defined between an anionic membrane 114 and a cationic membrane 118, and a third compartment 120 defined between a cationic membrane 118 and a bipolar membrane 122. The second compartment 116 is supplied with a salt, in particular sodium chloride or potassium chloride. Chloride ions pass through the anionic membrane 114 under the effect of an electric field towards the anode 125, while Na + , K + The ions pass under the effect of an electric field through the cationic membrane towards the cathode 127. This step v) makes it possible to regenerate acid and base salts, in particular hydrochloric acid and sodium hydroxide, of which the acid salts are fed to the first compartment of the unit cell 15 of step ii) and the base salts to the first compartment of the unit cell 35 of step iii).

[0103] The second example process for producing a demineralized milk protein composition shown in Figure 3 includes two electrodialysis devices 200 and 205, whose unit cells (215, 235) have three compartments. In Figure 3, a single unit cell 215 of the electrodialysis device 200 is shown. The unit cell 215 includes a first compartment 220 defined between an anionic membrane 222 and a cationic membrane 224, a second compartment 226 defined between a cationic membrane 224 and a cationic membrane 228, and a third compartment 230 defined between a cationic membrane 228 and an anionic membrane 232. Also shown in Figure 3 is a single unit cell 235 of the electrodialysis device 205. The unit cell 235 comprises a first compartment 239 defined between a cationic membrane 237 and an anionic membrane 241, a second compartment 243 defined between an anionic membrane 241 and an anionic membrane 245, and a third compartment 247 defined between an anionic membrane 245 and a cationic membrane 249. The electrodialysis devices 200 and 205 each comprise an anode (278, 290) and a cathode (280, 288) for generating an electric current via a conductive solution passing through the compartments of the unit cells 215 and 235. The process also comprises a first nanofiltration device 250 for performing step vi), a second nanofiltration device 260 for performing step vii), and a three-compartment bipolar membrane electrodialysis device 70, detailed in FIG. 2, for performing step v). The process further comprises a heat treatment device 275 for performing a heat treatment step viii).

[0104] In operation, a milk protein composition MPC, in particular whey that has been demineralized to at least 50%, is fed to the second compartment 226 of the electrodialysis device 200. At the same time, an acidifying salt, in particular a hydrochloric acid solution, is fed to the first compartment 220 and a brine, in particular a sodium chloride salt and a potassium chloride salt, is fed to the third compartment 230. +Only the cationic ions pass through the cationic membrane 224 into the second compartment 226 towards the cathode 280, and the chloride ions pass through the anionic membrane 232 into the third compartment 230 towards the anode 278. In the second compartment 226, Na + and Ca 2+ Under the influence of an electric field, monovalent or divalent cations such as H + ions. In this way, the milk protein composition of MPC1 obtained in step ii) is partially demineralized and the cations are replaced with H + ions and acidification. The pH of MPC1 is below 4. The third compartment 230 contains a mixture of CaCl2 and NaCl resulting from the milk protein composition MPC. Chloride ions from the first compartment 220 are provided to the third compartment 230 through the anion membrane 222 or 232.

[0105] The acidified milk protein composition MPC1 undergoes a heat treatment in step viii) in particular a heat treatment step (90°C for a few minutes) in order to improve its bacteriological stability. Advantageously, since the composition MPC1 is acidified, the conditions of the heat treatment can be defined in such a way that the proteins are not altered.

[0106] The salt mixture emerging from the third compartment 230 may undergo a nanofiltration step vi) in a nanofiltration unit 250 to increase the purity of the sodium chloride salt emerging from the third compartment 230 by removing divalent salts such as calcium chloride CaCl2. This step may optionally be followed by a chelating resin operation to achieve the input specification of 3-5 ppm in step v).

[0107] In particular, the heat-treated composition MPC1 undergoes a second electrodialysis step iii) in an electrodialysis device 205. The first compartment 239 is provided with a basic salt, such as sodium hydroxide, from step v). OH -The ions pass through the anionic membrane 241 to the second compartment 243, forming Na + The ions pass through the cationic membrane 249 towards the third compartment 247. In the second compartment 243, residual anions from the acidified and heat-treated MPC1, such as chloride and phosphate, pass through the anionic membrane 245 towards the anode 290 under the influence of an electric field, combining with the hydroxyl ions OH - The resulting composition of MPC2 is demineralized and deacidified in step iv). In the third compartment 247, a mixture of chloride salts of monovalent cations, including potassium and sodium chloride salts, phosphates, sulfates, is obtained from MPC1. Monovalent or divalent anions, such as chloride, phosphate, sulfate, etc., pass through the anion membrane 245 and are provided to the third compartment 247.

[0108] The salt from the third compartment 247 may undergo a nanofiltration step vii) to increase the purity of the sodium chloride salt emerging from the third compartment 247 by extracting phosphate ions.

[0109] This second example process also includes a step v) of treating sodium chloride salts in a three-compartment bipolar membrane electrodialysis unit 70 that allows the regeneration of acids (mainly HCl) and bases (mainly sodium hydroxide) from a NaCl stream obtained indirectly from the third compartments 230 and 247 of steps ii) and iii) of the cation and anion electrodialysis, since the NaCl stream has previously undergone a nanofiltration step of steps vi) and vii). Said NaCl stream may be obtained from NaCl from a prior demineralization step carried out upstream on the MPC composition of step i), whether or not mixed with the one obtained from steps ii) and iii), and / or from food-grade NaCl. Said prior demineralization step preferably consists of a nanofiltration step followed by a two-compartment electrodialysis step applied to the nanofiltration retentate. With the exception of the salts used at the start of steps ii) and iii), thanks to step v), the acid and basic salts used in carrying out the electrodialysis steps ii) and iii) originate from the milk protein composition MPC1, thereby avoiding the introduction of exogenous mineral compounds.

[0110] The process of the second example differs from the first example in that steps ii) and iii) do not involve a selectively permeable membrane and in that the NaCl stream treated by bipolar membrane electrodialysis is not obtained directly from electrodialysis devices 200 and 205 but goes through an intermediate nanofiltration step corresponding to steps vi) or vii).

[0111] The cation exchange step ii) can be carried out in either electrodialysis device 5 (FIG. 1) or 200 (FIG. 3).

[0112] The anionic displacement step iii) can be carried out in either electrodialysis device 10 (FIG. 1) or 205 (FIG. 3). EXAMPLES

[0113] To carry out the tests described below, a milk protein composition MPC was prepared by preparing a dispersion of 16% dry mass of sweet whey powder (crude) in demineralized water. The dispersion was mechanically stirred until a homogeneous mixture was obtained. The parameters of the MPC thus obtained were: mass proportion in dry matter: 15.9% (powder mass / total mass), pH=5.95, initial conductivity=10.95mS / cm, ash content by mass=8.1%, lactose content by mass=73.5%, cation content by mass (in particular Na, NH4, K, Ca, Mg)=3.79%, anion content by mass (in particular Cl, NO3, PO4, SO4): 3.64%, the various mass proportions (except those in the dry matter) being calculated by combining the total mass of one or more compounds with the total mass of the dry matter.

[0114] 1-Cation exchange in electrodialysis device 200 (Figure 3) The electrodialysis device 200 is composed of, for example, 5 to 15 cells 215. The first compartment 220 is supplied with an HCl solution having a conductivity of at least 100 mS / cm, in particular at least 150 mS / cm. The second compartment 226 is supplied with the MPC as exemplified above. The third compartment is supplied with a NaCl solution having a conductivity of at most 50 mS / cm, in particular at most 25 mS / cm, in this embodiment at most 15 mS / cm. A current (I) of at least 1 Ampere, in particular at most 2 Amperes, is applied to the electrodialysis device 200, the voltage being preferably free. During electrodialysis ii), the conductivity of the MPC decreases, indicating its demineralization, after which its constituent cations become H + ions are replaced, increasing. The pH of the resulting MPC1 is of the order of 1 and the conductivity of MPC1 is about 12 mS / cm. The conductivity of the acidic solution, i.e. HCl, at the outlet of the first compartment 220 decreases by about 74% and the conductivity of the brine, i.e. NaCl, obtained at the outlet of the third compartment 230 increases by about 234%. The cation removal is about 84%.

[0115] 2- Cation replacement in the electrodialysis device 5 (Fig. 1) The electrodialysis device 5 is composed of, for example, 5 to 15 cells 15. The first compartment 20 is supplied with an HCl solution having a conductivity of 100 mS / cm or more, in particular 150 mS / cm or more. The second compartment 26 is supplied with the MPC exemplified above. The third compartment is supplied with a NaCl solution having a conductivity of 50 mS / cm or less, in particular 25 mS / cm or less, in this example 15 mS / cm or less. A current (I) of 1 ampere or more, in particular 2 amperes or less, is applied to the electrodialysis device 5, and the voltage is preferably free. At the start of electrodialysis ii), the conductivity of the MPC decreases, indicating its demineralization, and then its constituent cations change to H + ions, increasing in the acidic compartment 20. + The conductivity decreases as ions are depleted and less conductive NaCl is produced. The cations extracted from the MPC are transferred to the brine compartment 30, which is enriched in multivalent cations that are more conductive than NaCl. The pH of the resulting MPC1 is of the order of 1 and the conductivity of the MPC1 is about 12 mS / cm. The conductivity of the acid solution at the outlet of the first compartment 220 has decreased by about 35% and the conductivity of the brine obtained at the outlet of the third compartment 30 has increased by about 25%. The cation removal is about 82%.

[0116] For the implementation of step iii), the MPC1 used may be either the one from electrodialysis device 5 or 200, since they have the same performance in terms of cation rejection.

[0117] 3- Anion replacement in electrodialysis device 205 (Figure 3) The electrodialysis device 205 is composed of, for example, 5 to 15 cells 235. The first compartment 239 is supplied with a NaOH solution having a conductivity of 30 mS / cm or more, in particular 50 mS / cm or more. The second compartment 243 is supplied with the MPC1 obtained above. The third compartment 247 is supplied with a NaCl solution having a conductivity of 50 mS / cm or less, in particular 25 mS / cm or less, in this embodiment 15 mS / cm or less. A current (I) of 1 ampere or more, in particular 2 amperes or less, is applied to the electrodialysis device 205, the voltage being preferably free. During the electrodialysis iii), the conductivity of MPC1 decreases, indicating its demineralization. The pH of the obtained MPC2 is greater than 6, in this embodiment of the order of 7.7, and the conductivity of MPC2 is about 1 mS / cm. The conductivity of the basic solution, i.e. NaOH, at the outlet of the first compartment 239 decreases by about 120% and the conductivity of the brine obtained at the outlet of the third compartment 247 increases by about 126%. The anion rejection is about 98%. The decrease in conductivity of the MPC until MPC2 is reached is 85%.

[0118] 4- Anion replacement in the electrodialysis device 10 (Fig. 1) The electrodialysis device 10 is composed of, for example, 5 to 15 cells 35. The first compartment 39 is supplied with a NaOH solution having a conductivity of 30 mS / cm or more, in particular 50 mS / cm or more, in this embodiment 80 mS / cm or more. The second compartment 43 is supplied with the above-mentioned MPC1. The third compartment 47 is supplied with a NaCl solution having a conductivity of 50 mS / cm or less, in particular 25 mS / cm or less, in this embodiment 15 mS / cm or less. A current (I) of 1 ampere or more, in particular 2 amperes or less, is applied to the electrodialysis device 10, the voltage being preferably free. During the electrodialysis iii), the conductivity of MPC1 decreases, indicating its demineralization. The pH of the resulting MPC2 is above 6, in the order of 7, and the conductivity of MPC2 is about 2 mS / cm. The conductivity of the basic solution at the outlet of the first compartment 39 is reduced by about 21%, and the conductivity of the brine obtained at the outlet of the third compartment 47 is reduced by 25%. The anion removal rate is about 84%. The conductivity reduction rate of the MPC until reaching MPC2 is 77%.

[0119] Depending on the desired demineralization rate, for example by combining cationic substitution according to points 1 or 2 exemplified above with anionic substitution according to point 3 exemplified above, it is possible to reach a demineralization rate of 90% at an ash content of less than 1.5% on dry matter (DM) starting from the MPC exemplified above.

[0120] It is possible that the starting MPC is already partially demineralized, which allows for the combination of the exemplary anionic substitution according to item 4 above with the cationic substitution according to the present invention.

[0121] For the tests described below, a milk protein composition MPC″ was prepared by preparing a dispersion of 17% dry weight of sweet whey powder (crude) in demineralized water. This dispersion is mechanically stirred until a homogeneous mixture is obtained. The parameters of the MPC″ thus obtained are: mass percentage of dry matter: 17% (powder mass / total mass), pH=5, initial conductivity: 12 mS / cm, mass percentage of ash: 8%, mass percentage of lactose: 74%, mass percentage of cations (in particular Na, NH4, K, Ca, Mg): 5%, mass percentage of anions (in particular Cl, NO3, PO4, SO4): 3%, the various mass percentages (except the mass percentages of dry matter) being calculated by linking the total mass of one or more compounds to the total mass of dry matter.

[0122] 5. Cation Exchange (ESC) in Electrodialysis Device 200 (FIG. 3) The electrodialysis device 200 is composed of, for example, 5 to 15 cells 215. The first compartment 220 is supplied with an HCl solution having a conductivity of 100 mS / cm or more, in particular 150 mS / cm or more. The second compartment 226 is supplied with the above-mentioned exemplary MPC″. The third compartment is supplied with a NaCl solution having a conductivity of 50 mS / cm or less, in particular 25 mS / cm or less, in this embodiment 15 mS / cm or less. A current (I) of 2 Amperes or more, in particular 3 Amperes or less, is applied to the electrodialysis device 200, the voltage being preferably free. During the electrodialysis ii), the conductivity of the MPC″ decreases, indicating its demineralization, after which its constituent cations become H + ions are replaced by ions, increasing. The pH of the resulting MPC1″ is about 2 and the conductivity is about 12 mS / cm. The conductivity of the acid solution obtained at the outlet of the first compartment 220, i.e. HCl, is reduced by about 53%, while the conductivity of the brine obtained at the outlet of the third compartment 230, i.e. NaCl, is increased by about 292%. The cation removal (or replacement) rate is about 77%. The anion rate is substantially similar between MPC″ and MPC1″.

[0123] 6. Conventional two-compartment electrodialysis (ED) (anionic membrane / cationic membrane) The electrodialysis device (not shown in the drawing) comprises, for example, 5 to 15 cells. The first compartment is separated by a cationic and an anionic membrane, the second compartment by an anionic and a cationic membrane. The first compartment is supplied with the above-mentioned MPC1″, the second compartment with a salt having a conductivity between 5ms / cm and 15ms / cm, in particular sodium chloride. During the test, a voltage between 10V and 20V, in particular 15V, is applied to the two-compartment electrodialysis device and the current (I) is freed. During the test, the conductivity of MPC1″ decreases, indicating its demineralization. H + Some of the ions are extracted into the brine compartment and therefore the pH of the MPC1″(ESC+ED) at the outlet increases, especially to a pH above 2.5, especially above 3. Thanks to this conventional electrodialysis, the final conductivity of the MPC1″(ESC+ED) is reduced by about 90% compared to the MPC. The cation (Na, NH4, K, Ca, Mg) removal rate in the MPC1″(ESC+ED) is more than 90% (comparison with MPC1″ obtained at the outlet of the cation-exchanged ED, Fig. 3). The anion (Cl, NO3, PO4, SO4) removal rate in the MPC1″(ESC+ED) is more than 80% (comparison with MPC1″ obtained at the outlet of the cation-exchanged ED, Fig. 3).

[0124] 7. Anion substitution (ESA) in electrodialysis device 205 (FIG. 3) The electrodialysis device 205 is composed, for example, of 5 to 10 cells 235. The first compartment 239 is supplied with a NaOH solution having a conductivity of 20 to 35 mS / cm. The second compartment 243 is supplied with the MPC1″(ESC+ED) obtained above. The third compartment 247 is supplied with a NaCl solution having a conductivity of less than 50 mS / cm, in particular less than 25 mS / cm, in this embodiment less than 15 mS / cm. A voltage between 10 V and 15 V is applied, the current (I) being preferably free. During the electrodialysis iii), the conductivity of the MPC1″(ESC+ED) decreases, indicating demineralization. The anions extracted from MPC1″ (ESC+ED) migrate to the third compartment containing brine. The resulting pH of MPC2″ is higher than 4, in this example of the order of 5, and the conductivity of MPC2″ is lower than 1. The conductivity of the basic solution, i.e. NaOH, at the outlet of the first compartment 239 has decreased by more than 55% and the conductivity of the brine at the outlet of the third compartment 247 has increased by more than 35%. The conductivity reduction from MPC″ to MPC2″ is more than 95%. The final reduction (between MPC″ and MPC2″) for both anions and cations is more than 95%.

Claims

1. 1. A process for producing a demineralized milk protein composition (MPC2), comprising the steps of: (i) providing a milk protein composition (MPC); (ii) electrodialysing said milk protein composition (MPC) in an electrodialysis device (5, 200), the unit cell (15, 215) of said electrodialysis device having three compartments (20, 26, 30; 220, 226, 230) and converting at least one cation in said milk protein composition (MPC) into at least one hydrogen ion H ＋ to obtain an at least partially demineralized and acidified milk protein composition (MPC1); (iii) electrodialysing the milk protein composition (MPC1) obtained in step (ii) in an electrodialysis device (10, 205), the unit cell of which has three compartments (39, 43, 47; 239, 243, 247) and which converts at least one anion in the milk protein composition into at least one hydroxyl ion OH － configured to replace the (iv) Obtaining a demineralized milk protein composition (MPC2) A process comprising:

2. The following salts: the salt obtained directly from the electrodialysis step (ii), - a salt obtained indirectly from the electrodialysis step (ii), the salt obtained directly from the electrodialysis step (iii), - a salt obtained indirectly from the electrodialysis step (iii), - salts from a prior demineralization step carried out on the milk protein composition in step (i); Mixtures of these 10. The process of claim 1, further comprising a step (v) of treating at least a portion of the salts selected from the group consisting of:

3. 3. The process of claim 2, wherein the treating step (v) comprises an electrodialysis step carried out in a bipolar membrane electrodialysis device (70).

4. 4. The process according to claim 3, characterized in that the bipolar membrane electrodialysis device (70) in step (v) comprises a unit cell (105) having three compartments A, B and C (110, 116, 120), the compartments A and B being supplied with water and the compartment C, located between the compartments A and B, being supplied with one or more salts.

5. 5. The process according to claim 2, characterized in that at least a portion of the salt obtained in the treating step (v) is fed to one of the three compartments (20, 26, 30; 220, 226, 230) of the electrodialysis device (5, 200) in step (ii).

6. The manufacturing process of claim 5, wherein the salt is hydrochloric acid and / or sulfuric acid.

7. 7. The process according to any one of claims 2 to 6, characterized in that at least a portion of the salt obtained in the treating step (v) is fed to one of the three compartments (39, 43, 47; 239, 243, 247) of the electrodialysis device (10, 205) in step (iii).

8. The process of claim 7, wherein the salt is sodium hydroxide and / or potassium hydroxide.

9. 9. A process according to any one of claims 1 to 8, characterised in that it comprises a step of electrodialysis of the at least partially demineralised and acidified milk protein composition (MPC1) obtained in step (ii) in an electrodialysis device equipped with a two-compartment unit cell prior to step (iii).

10. 10. The process according to any one of claims 1 to 9, characterized in that in the electrodialysis step (ii) a mixture is produced comprising at least one chloride salt of a monovalent cation and at least one chloride salt of a divalent cation, said mixture undergoing a separation step (vi) of said chloride salts of monovalent cations and of said chloride salts of divalent cations.

11. 11. The process according to any one of claims 1 to 10, characterized in that in the electrodialysis step (iii) a mixture comprising at least one sodium salt of a monovalent anion and at least one sodium salt of a divalent anion is produced, said mixture undergoing a separation step (vii) of said sodium salt of a monovalent anion and said sodium salt of a divalent anion.

12. The manufacturing process of claim 10 or claim 11, wherein the separation step (vi) or the separation step (vii) is nanofiltration.

13. 12. The process according to claim 10 or 11, characterized in that the salt of a monovalent cation collected on completion of the separation step (vi) and / or the separation step (vii) is fed to the electrodialysis step (ii) and / or the electrodialysis step (iii).

14. 12. The process according to claim 10 or 11, characterized in that the salt of the monovalent cation collected on completion of the separation step (vi) and / or the separation step (vii) has at least partially undergone the treating step (v).

15. The process of claim 13 or 14, wherein the salt of the monovalent cation is a chloride salt of the monovalent cation.

16. 16. The process according to any one of the preceding claims, characterized in that the electrodialysis device (5) in step (ii) comprises at least one membrane (22, 32) having selective permeability for monovalent cations.

17. The three-compartment (20, 26, 30) unit cell (15) of the electrodialysis device (5) in step (ii) comprises A first compartment (20) defined between a membrane (22) having selective permeability to monovalent cations and a cationic membrane (24); a second compartment (26) defined between two cationic membranes (24, 28); a third compartment (30) defined between the cationic membrane (28) and a membrane (32) having selective permeability to monovalent cations; The manufacturing process according to any one of the preceding claims, characterized in that it comprises at least one unit cell (15) comprising:

18. The three-compartment (220, 226, 230) unit cell (215) of the electrodialysis device (200) in step (ii) comprises a first compartment (220) defined between an anionic membrane (222) and a cationic membrane (224); a second compartment (226) defined between two cationic membranes (224, 228); and a third compartment (230) defined between the cationic membrane (228) and the anionic membrane (232); The manufacturing process according to any one of claims 1 to 17, characterized in that it comprises at least one unit cell (215) comprising:

19. 19. The process according to claim 17 or 18, characterized in that the first compartment (20, 220) is supplied with at least one acid salt, the second compartment (26, 226) is supplied with the milk protein composition (MPC) of step (i) and the third compartment (30, 230) is supplied with at least one chloride salt of a monovalent cation.

20. The process of claim 19, wherein the at least one acid salt is hydrochloric acid.

21. 21. The process according to any one of the preceding claims, characterized in that the electrodialysis device in step (iii) comprises at least one membrane (37, 49) having selective permeability for monovalent anions.

22. The three-compartment (39, 43, 47) unit cell (35) of the electrodialysis apparatus in step (iii) comprises a first compartment (39) defined between a membrane (37) selectively permeable to monovalent anions and an anionic membrane (41); A second compartment (43) defined between two anionic membranes (41, 45); a third compartment (47) defined between the anionic membrane (45) and a membrane (49) having selective permeability to monovalent anions; 22. The manufacturing process according to any one of claims 1 to 21, characterized in that it comprises at least one unit cell (35) comprising:

23. The three-compartment (239, 243, 247) unit cell (235) of the electrodialysis device (205) in step (iii) comprises A first compartment (239) defined between a cationic membrane (237) and an anionic membrane (241); A second compartment (243) defined between two anionic membranes (241, 245); a third compartment (247) defined between the anionic membrane (245) and the cationic membrane (249); The manufacturing process according to any one of claims 1 to 22, characterized in that it comprises at least one unit cell (235) comprising:

24. 24. Process according to claim 22 or 23, characterized in that the first compartment (39, 239) is supplied with at least one basic salt, the second compartment (43, 243) is supplied with the partially demineralized and acidified milk protein composition (MPC1) obtained in step (ii) and the third compartment (47, 247) is supplied with at least one chloride salt of a monovalent cation.

25. The process of claim 24, wherein the at least one basic salt is sodium hydroxide.

26. A manufacturing process according to any one of the preceding claims, characterized in that it comprises a heat treatment step (viii) (75, 275) carried out after step (ii) and before step (iii).

27. 27. The process according to any one of claims 1 to 26, characterized in that the milk protein composition (MPC) in step (i) is whey.

28. The production process according to claim 27, characterized in that the milk protein composition (MPC) in step (i) is whey derived from organic agriculture.

29. 29. The process according to any one of the preceding claims, characterized in that the milk protein composition (MPC) in step (i) is partially demineralized whey.

30. The process of claim 29, wherein the milk protein composition (MPC) in step (i) has undergone at least one step selected from an electrodialysis step, a nanofiltration step, a reverse osmosis step, an evaporation step, and combinations thereof.

31. A demineralized milk protein composition (MPC2) obtainable by the manufacturing process according to any one of claims 1 to 30.

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