JPH07184556A - Proteinaceous very fine particle and its production - Google Patents

Abstract

PURPOSE:To obtain the subject particles useful as a fat substitute having smooth and glossy solid fat and oil-like physical properties without heating and high shearing by treating a solution of a whey protein containing a metal element by a specific method. CONSTITUTION:First, the pH of a solution of a whey protein containing a metal element (preferably Ca) is reduced with hydrochloric acid to preferably 3-5 under non-heating conditions to remove insoluble materials such as casein. Then the pH of the solution is raised preferably to 7 and the solution is mixed with a hydrophilic organic solvent (preferably ethanol) to deposit the objective particles. The solution of the whey protein containing the metal element preferably has 0.1-5wt.% protein concentration and 1.5 millimol-1.5mol metal element concentration based on 1g whey protein. The mount of the hydrophilic organic solvent used is preferably 0.5-2 times (V/V) as much as the solution of the whey protein.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to proteinaceous microparticles useful as a fat-free fat substitute and a method for producing the same.

[0002]

2. Description of the Related Art Whey protein is a protein present in milk, composed of lactalbumin, lactoglobulin and the like, and has a property of being heat-denatured at a temperature of 72 to 75 ° C. Whey protein has been studied for use in foods by applying its functional aspects such as solubility, emulsification and gelation. Recently, use as a texture material as a substitute for fat has been particularly proposed. Fat substitutes using proteins are roughly classified into gel compositions and emulsion-like compositions.
Most emulsion-like compositions using whey protein that have been known so far produce microsphere particles by using heat denaturation or high shearing action.
Singer et al. (JP-A-63-24857, U.S. Pat. No. 4,
734,287) discloses a micronized denatured protein fat substitute made from whey protein. It is a giant colloid of spherical particles formed by heating an aqueous whey protein solution under high shear conditions. Also, U.S. Pat. No. 4,143,
No. 174 discloses the use in food of colloidal precipitates obtained from whey solutions. This is a non-protein one which is formed by concentrating the ultrafiltration permeate of whey and then heating it to raise the pH to form an insoluble colloidal precipitate. In addition, as a method for producing proteinaceous fine particles that does not use heat denaturation, a hydrophobic protein solubilized in an organic solvent is used.
There is also a method of dispersing in an aqueous solution (JP-A-4-502).
102, U.S. Pat. No. 246,435). However, since whey protein is a water-soluble protein, this method cannot be used. Further, as an example of using insoluble salts as an emulsion-like fat substitute, fine particles of titanium oxide and fine particles of calcium citrate (JP-A-5-260).
No. 906, US Pat. No. 5,219,602) and the like, but they cannot be completely replaced with fat or cannot be used in large amounts in foods because of their rough feeling and astringent taste.

[0003]

SUMMARY OF THE INVENTION As mentioned above,
In order to form a fat substitute that gives an emulsion-like texture using a whey protein solution, a method of denaturing by heating under high shear conditions to form proteinaceous fine particles has been widely used. However, most of the proteinaceous fine particles obtained by these methods have rather creamy physical properties, and almost none have solid fat-like physical properties.

[0004]

Techniques for producing foods by utilizing protein denaturation are well known, but protein denaturation generally means that the structure of the protein molecule partially changes, It means that the shape changes. During protein denaturation, protein molecules are deformed, associated, and aggregated, resulting in aggregates. It is the intermolecular bonds such as hydrophobic bonds, hydrogen bonds, salt bonds, etc. that are responsible for the association and aggregation, but it is difficult to understand these relationships and consequently predict specific physical properties and properties. is there. Under the circumstances, as a result of earnest research, the present inventors have surprisingly reduced the pH of a whey protein-containing solution containing a metal element by using an acid to remove the insoluble matter, and then increase the pH. By mixing with a hydrophilic organic solvent, without heating,
It was found that proteinaceous microparticles can be obtained without subjecting them to high shearing, and these proteinaceous microparticles have a smooth and glossy solid fat-like physical property and are useful as a fat substitute, thus completing the present invention. Came to do.

That is, according to the present invention, (1) the pH of a whey protein-containing solution containing a metal element is lowered by using an acid to remove insolubles, then the pH is raised, and further mixed with a hydrophilic organic solvent. The proteinaceous microparticles thus obtained, (2) the proteinaceous microparticles described in (1) above which is obtained without heating, and (3) the whey protein-containing solution containing a metal element whose protein concentration is the whey protein-containing solution. For 0.0
The proteinaceous microparticles according to (1) above, which is 5 to 10% by weight, (4) the proteinaceous microparticles according to (1) above, wherein the metal element is derived from the added metal salt, and (5) the metal element ,
The proteinaceous microparticles according to (1) above, which is derived from the added natural mineral material, (6) the proteinaceous microparticles according to (5) above, wherein the natural mineral material is whey mineral or beef bone powder. (6) The proteinaceous microparticles described above in which the natural mineral material is whey calcium, (8) the proteinaceous microparticles described in (1) above in which the acid is hydrochloric acid, sulfuric acid, lactic acid, acetic acid or phosphoric acid, ( 9) After the insoluble matter is removed, the pH is raised to 6 to 9, and the hydrophilic organic solvent is added in an amount of 0.3 times or more ((10) whey protein-containing solution). v / v) The proteinaceous microparticles described in (1) above, and (11) the hydrophilic organic solvent is a monovalent or polyvalent alcohol having 1 to 5 carbon atoms, described above in (1). , (12) the hydrophilic organic solvent is ethanol (13) The whey protein-containing liquid containing the proteinaceous microparticles (1) and the metal element (13), wherein acid whey is used instead of reducing the pH with an acid to remove the insoluble matter. Proteinaceous microparticles, (14) proteinaceous microparticles according to the above (13), wherein the protein in the acid whey is 0.05 to 10% by weight with respect to the acid whey, (15) a whey protein-containing solution containing a metal element After the pH is lowered with an acid to remove the insoluble matter,
And the resulting insoluble matter is separated, and the supernatant after separation is mixed with a hydrophilic organic solvent to obtain the above (1).
(16) Decreasing the pH of the whey protein-containing solution containing the proteinaceous microparticles and (16) metal element by using an acid to remove insolubles, then increasing the pH, and further mixing with a hydrophilic organic solvent. (17) The method for producing proteinaceous microparticles, (17) the method according to the above (16) which is carried out without heating, and (18) the whey protein-containing solution containing a metal element whose protein concentration is the whey protein-containing solution. Against 0.05
(19) The production method according to the above (16), which comprises 10% by weight.
The protein concentration of acid whey is 0.05 to 5
(20) The production method according to the above (16), which is 10% by weight.
The pH of the whey protein-containing solution containing a metal element is reduced with an acid to remove insolubles, the pH is increased, the resulting insolubles are separated, and the supernatant after the separation is mixed with a hydrophilic organic solvent. The present invention also relates to the production method according to the above (16).

The whey protein-containing solution containing a metal element used in the present invention means a liquid material such as a solution, suspension or emulsion containing a metal element and whey protein. Preferably, such aqueous solutions, suspensions and emulsions are used, more preferably aqueous solutions. As for whey protein,
For example, whey protein itself such as commercially available whey protein concentrate, whey protein isolate, etc.,
For example, ordinary dairy products containing whey protein such as raw milk, skim milk, skim milk powder, etc. can be used. Of these, whey protein concentrate, whey protein isolate, skim milk and skim milk powder are preferred.

When the protein content of the whey protein-containing liquid is high, protein aggregates are formed, and the paste separated by centrifugation or the like has coarse and rough particles.
In order to avoid this, high shearing action can be used, but in the present invention, it can be controlled simply by lowering the concentration of whey protein. From this point of view, the protein concentration in the whey protein-containing solution containing the metal element used in the present invention is usually 0.05 to 10% by weight, preferably 0.1 to 5% by weight, based on the whey protein-containing solution. is there. Since the actual whey protein of milk is within such a range, the protein concentration of whey obtained by treating skim milk with casein with acid (sometimes referred to as acid whey in this specification) is adjusted. Instead, it can be used as it is as a whey protein. While the whey protein needs to be concentrated in the production of proteinaceous fine particles using many whey proteins, the acid whey of the present invention can be further diluted before use. That is, the acid whey obtained during the production of caseinate can be used without concentration or desalting treatment by ultrafiltration or the like.

The metal element contained in the whey protein-containing liquid is not particularly limited as long as it is used in foods.
Examples thereof include sodium, potassium, magnesium, calcium, iron and zinc. Of these, divalent metals are preferable, and calcium is more preferable. These metal elements in the present invention include any possible form such as those existing as free ions in the whey protein-containing solution and those existing after being incorporated into proteins.
The concentration of the metal element in the whey protein-containing liquid is 0.6 mmol-1.5 mol, preferably 1.5 m per 1 g of whey protein.
mol to 1.5 mol.

The metal element may be derived from an added metal salt. In particular, when whey protein itself, that is, whey protein concentrate, whey protein isolate, etc. is used as the whey protein, these whey proteins are used. A metal salt is usually added to the liquid containing. As a metal salt,
Sodium salts (eg sodium chloride, sodium sulfate,
Sodium nitrate, sodium phosphate, etc.), potassium salt (eg, potassium chloride, potassium sulfate, potassium nitrate, potassium phosphate, etc.), magnesium salt (eg, magnesium chloride, magnesium sulfate, etc.), calcium salt (eg, calcium phosphate, calcium lactate, Examples thereof include calcium chloride, calcium citrate, etc., iron salts (eg, iron chloride, iron sulfate, etc.), zinc salts (eg, zinc chloride, zinc sulfate, etc.), and the like. Further, the metal element may be derived from the added natural mineral material, instead of the metal salt,
Alternatively, a natural mineral material such as whey mineral (eg, whey calcium, etc.) or beef bone powder may be added together with the metal salt. 2 of the above metal salts or natural mineral materials
Those containing a valent metal are preferable, and those containing calcium (eg, calcium phosphate, calcium lactate, whey calcium, etc.) are more preferable. When calcium-containing ones are used, the resulting proteinaceous microparticles contain high concentrations of calcium and, in addition to fat replacement, provide added value of calcium fortification. Some calcium salts are insoluble in the neutral range, but in the present invention, the calcium salt can be solubilized with an acid before use.

When raw milk, skimmed milk, and skim milk powder are used as the whey protein source, it is not necessary to add a metal salt or a natural mineral material because the naturally-occurring metal element is contained in these. If desired, the above metal salt or natural mineral material may be added.

The proteinaceous microparticles of the present invention are usually prepared by lowering the pH of a whey protein-containing solution containing a metal element with an acid under non-heating, removing insolubles, and then increasing the pH. It can be manufactured. That is, first, the whey protein-containing solution containing a metal salt is usually adjusted to pH 6 or less, preferably pH 3 to 5, and insoluble matter such as casein present in the solution is removed under such low pH. The acid used is not particularly limited as long as it is used in foods, and examples thereof include inorganic acids such as hydrochloric acid, sulfuric acid and phosphoric acid; and organic acids such as lactic acid and acetic acid. Insoluble matter can be removed by
For example, it can be performed by an ordinary separation method such as centrifugation or filtration. Then, the obtained solution is treated with a base,
Usually, the pH is adjusted to 6 to 9, preferably about 7. The base used is not particularly limited as long as it is used in foods, and examples thereof include sodium hydroxide and potassium hydroxide.

Further, by mixing the liquid having an increased pH with the hydrophilic organic solvent, the proteinaceous microparticles are precipitated in the liquid. Examples of the hydrophilic organic solvent used include monohydric or polyhydric alcohols (eg, methanol, ethanol, propanol, butanol, ethylene glycol, glycerin, etc.), ethers (eg, tetrahydrofuran, dioxane, etc.), nitriles ( Example,
Acetonitrile and the like). Of these, monohydric or polyhydric alcohols having 1 to 5 carbon atoms are preferable. Further, since the proteinaceous microparticles of the present invention are for foods, a solvent used for foods such as ethanol is more preferable. The hydrophilic organic solvent is usually 0.3 times or more (v / v), preferably 0.3, the amount of the whey protein-containing liquid.
˜5 times amount (v / v), more preferably 0.5 to 2 times amount (v / v) is used. Since the precipitated proteinaceous microparticles contain a hydrophilic organic solvent, the hydrophilic organic solvent can be removed or the concentration thereof can be reduced, if desired. As a method for removing the hydrophilic organic solvent or reducing the concentration thereof, for example, a usual separation method such as washing with water, centrifugation, and filtration can be used.

Further, as described above, acid whey can be used instead of lowering the pH of the whey protein-containing solution containing a metal element with an acid to remove insoluble matter. That is, the pH of skim milk is lowered by using the above-mentioned acid, and insoluble matters such as casein are similarly removed. In this case, since some casein contamination is not a problem, the pH is 6 or less,
The pH is preferably 3-5. The casein-free solution (acid whey) can then be adjusted to pH 6-9, preferably about pH 7, and then mixed with a hydrophilic organic solvent to precipitate proteinaceous microparticles.

PH of a whey protein-containing solution containing a metal element
May be reduced with an acid to remove the insoluble matter, and then the pH may be increased to newly form an insoluble matter. At this time, the formed insoluble matter is removed by a usual method such as centrifugation or filtration, and the supernatant is mixed with a hydrophilic organic solvent to form proteinaceous microparticles. If the insoluble matter formed when the pH is raised does not significantly affect the physical properties of the proteinaceous microparticles, the suspension of the insoluble matter and the hydrophilic organic solvent are combined. They may be mixed to form proteinaceous microparticles. For example, if 2-fold diluted acid whey is used, p
Since insoluble matter generated by increasing H is hardly generated, the pH of diluted acid whey is increased and then immediately mixed with a hydrophilic organic solvent to precipitate proteinaceous microparticles. The paste of proteinaceous fine particles obtained by the above method has a smooth, glossy, solid fat-like physical property.

The proteinaceous microparticles of the present invention contain 7,000 g.
Solid content of paste obtained by centrifuging for 20 minutes at
To 50% by weight, ash content and protein content on a dry matter basis are 20 to 60% by weight and 10 to 80% by weight, respectively, and a particle size is 0.01 to 1 μm, preferably an average particle size of 0.
It is less than 5 μm. Compared with conventional fat substitutes using whey protein, the proteinaceous microparticles of the present invention are characterized by a high ash content, and the high ash content is involved in the physical properties of the proteinaceous microparticles. . When calcium salts are used, the proteinaceous microparticles contain calcium / protein in a ratio of 0.2 to 2, respectively. By using the calcium salt, the proteinaceous microparticles contain a large amount of calcium, and the added value of calcium fortification can be obtained.

Since the proteinaceous microparticles of the present invention have a high ash content, the particles have an appropriate hardness, and as a result, they are smoother and have less shear stress than other fat substitutes using protein microparticles. Physical properties closer to those of high solid fats and oils are obtained. Compared with a fat substitute using insoluble salt fine particles, it has no rough feeling and does not have an astringent taste, so it can be completely replaced with fat or used in a large amount. The proteinaceous microparticles of the invention are useful as a fat substitute without fat and cholesterol,
Margarine, butter, fat spreads, various beverages, salad dressings, low-fat or non-fat mayonnaise type seasonings as they are, or in ordinary formulation forms, for example, freeze-drying or spray-drying drying methods. It can be used as a powder or granule formulation used.

[0017]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. Example 1 A 10% by weight aqueous solution of skim milk powder was added with hydrochloric acid to a pH of 4.6.
Then, the mixture was centrifuged at 7,000 g for 15 minutes to remove casein. The acid whey obtained was adjusted to pH 7 with sodium hydroxide solution, and the resulting insoluble matter was 7,000 g,
It was removed by centrifugation for 15 minutes. Then, the supernatant after centrifugation was mixed with an equal amount of ethanol, and the resulting proteinaceous microparticles were separated by centrifugation at 7,000 g for 15 minutes. Since the obtained proteinaceous microparticles contain a high concentration of ethanol, in order to reduce the ethanol content, 3 times the amount of ion-exchanged water was added, stirred and dispersed, and then 7,000 g for 15 minutes Then, the mixture was centrifuged and separated. The proteinaceous fine particles were obtained as a transparent white composition and exhibited physical properties similar to solid fats and oils.

Example 2 A 10% by weight aqueous solution of skim milk powder was added with hydrochloric acid to a pH of 4.6.
Then, the mixture was centrifuged at 7,000 g for 15 minutes to remove casein. Calcium lactate was added to the obtained acid whey in an amount of 7.0% by weight, and stirred and dissolved. This solution was adjusted to pH 7 with a sodium hydroxide solution, then mixed with an equal amount of ethanol, and the resulting proteinaceous microparticles were separated by centrifugation at 7,000 g for 15 minutes. Since the obtained product contains a large amount of ethanol, in order to reduce the ethanol content, the product was dispersed in 3 times the amount of ion-exchanged water and centrifuged at 7,000 g for 15 minutes for separation. The proteinaceous fine particles were obtained as a transparent white composition and exhibited physical properties similar to solid fats and oils.

Example 3 A 10% by weight aqueous solution of skim milk powder was added with hydrochloric acid to a pH of 4.6.
Then, the mixture was centrifuged at 7,000 g for 15 minutes to remove casein. The obtained acid whey was adjusted to pH 7 with sodium hydroxide solution to obtain a suspension of proteinaceous microparticles. An equal amount of ethanol was mixed with this suspension, and the resulting proteinaceous microparticles were separated by centrifugation at 7,000 g for 15 minutes. Since the obtained product contains ethanol at a high concentration, in order to reduce the ethanol content, 3 times the amount of ion-exchanged water was added, stirred and dispersed, and then centrifuged at 7,000 g for 15 minutes. Separated and separated. The proteinaceous fine particles were obtained as a transparent white composition and exhibited physical properties similar to solid fats and oils.

Example 4 Whey protein concentrate [WPC; 81% by weight of protein, manufactured by Leprino, USA] was dissolved in ion-exchanged water to a concentration of 0.4% by weight, and whey minerals (Kyodo Dairy, NEP -2
0) was added so as to be 3.0% by weight. This solution was adjusted to pH 3 with hydrochloric acid, and insoluble matter was removed by centrifugation. The pH was then adjusted to 7 with sodium hydroxide solution. Further, it was mixed with an equal amount of ethanol, and the resulting proteinaceous microparticles were separated by centrifugation. Since the separated proteinaceous microparticles contain ethanol at a high concentration, they were dispersed in 3 times the volume of ion-exchanged water and separated by centrifugation in order to reduce the ethanol content. The proteinaceous microparticles were obtained as a white composition and exhibited fat-like physical properties.

Example 5 WPC was dissolved in ion-exchanged water to a concentration of 0.4% by weight, and calcium lactate was added to a concentration of 1.3% by weight. The solution was adjusted to pH 4.6 with phosphoric acid, and the insoluble fraction was removed by centrifugation. Then, the pH was adjusted to 7.0 with sodium hydroxide solution, and then mixed with an equal amount of ethanol, and the resulting proteinaceous microparticles were separated by centrifugation. Since the obtained proteinaceous microparticles contained ethanol at a high concentration, they were suspended in 3-fold amount of ion-exchanged water and separated by centrifugation in order to reduce the ethanol content. The proteinaceous microparticles were obtained as a white composition and exhibited fat-like physical properties.

Example 6 Whey protein isolate (WPI; MLA manufactured by Meiji Co., Ltd., 97% by weight of protein) was dissolved in ion-exchanged water to a concentration of 0.78% by weight, and tribasic calcium phosphate was added at 0.25% by weight. Was added. This was adjusted to pH 3.3 with lactic acid, and the insoluble fraction was removed by filtration. The filtrate was adjusted to pH 7.0 with sodium hydroxide solution. The resulting insoluble matter was removed by centrifugation. Next, the supernatant was mixed with an equal amount of ethanol, and the resulting proteinaceous microparticles were separated by centrifugation. Since these proteinaceous microparticles contain a high concentration of ethanol, 3
It was suspended in a double amount of ion-exchanged water and separated by centrifugation. The proteinaceous microparticles are obtained as a white composition,
It showed physical properties similar to solid fats and oils.

Example 7 Skim milk (after defatting raw milk, 95 ° C., 15 minutes, heat sterilization) was diluted 2-fold with water, and then adjusted to pH 4.6 with hydrochloric acid,
The casein was removed by centrifugation at 7,000 g for 15 minutes. The obtained acid whey is pour with sodium hydroxide solution.
Adjust to H7 and remove the resulting insoluble matter at 7,000g for 15 minutes.
It was removed by centrifugation. Then, an equal amount of ethanol is mixed with the supernatant after centrifugation, and the resulting proteinaceous microparticles are
It was separated by centrifugation at 7,000 g for 15 minutes. Since the obtained proteinaceous microparticles contain a high concentration of ethanol, in order to reduce the ethanol content, 3 times the amount of ion-exchanged water was added, stirred and dispersed, and
It was separated by centrifugation at 0 g for 15 minutes. Proteinaceous microparticles are obtained as a transparent white composition,
It showed physical properties similar to solid fats and oils. The particle size distribution of the obtained proteinaceous microparticles was measured by an electrophoretic light scattering photometer (ELS-800,
It was measured using Otsuka Electronics. For this particle size analysis, a small amount of the paste of proteinaceous fine particles is suspended in water and further sonicated for dispersion. Then, this dispersion was diluted to a concentration suitable for the measurement, and the measurement was performed. The results are shown in Fig. 1. FIG. 1 is a semi-logarithmic histogram showing the particle size distribution based on the weight standard obtained as described above.

Example 8 Proteinaceous microparticles were pulverized using a spray dryer. That is, to the paste 1 of proteinaceous microparticles obtained in Example 7, water 1.5 and maltitol (Mabit, Hayashibara Shoji) 0.05 were added and mixed well to prepare a dispersion liquid. The dispersion liquid was heated at a inlet temperature of 85 ° C. using a mobile minor type spray dryer (Niro).
Spray drying was performed at an outlet temperature of 50 ° C. The obtained powder was white and had fluidity, and it was possible to easily add water to obtain the same fat-like paste as before drying.

[0025]

INDUSTRIAL APPLICABILITY The present invention provides proteinaceous microparticles useful as a fat-free fat substitute and a method for producing the same. Unlike the conventional ones, the proteinaceous microparticles of the present invention can be obtained without heating or applying a high shearing action, have a high ash content, and have a smooth and glossy solid fat-like physical property. In addition, the added value of calcium fortification can be obtained.

[Brief description of drawings]

1 is a semi-logarithmic histogram showing a particle size distribution based on weight of proteinaceous microparticles obtained in Example 7. FIG. The horizontal axis represents the particle size, and the vertical axis represents the relative frequency and its cumulative frequency.

Front page continuation (72) Inventor Yoshihiro Yamamoto 2 Heights Mind 203 at 8-21 Ogino, Itami City, Hyogo Prefecture (72) Inventor Tetsuo Nunome 13-13, Koto, Kawanishi City, Hyogo Prefecture Maison Kimura 305 (72) ) Inventor Kotaro Muroyama 2-20 Founder, Itami City, Hyogo Prefecture Takeda Shokuhin Kogyo Co., Ltd. Men's dormitory (72) Inventor Hiroaki Kusaka 3-3-202 Asakura Minami, Takarazuka City, Hyogo Prefecture

Claims (20)

[Claims] 1. A p of a liquid containing whey protein containing a metal element.
A proteinaceous microparticle obtained by lowering H with an acid to remove insoluble matter, then increasing pH, and further mixing with a hydrophilic organic solvent. 2. The proteinaceous microparticle according to claim 1, which is obtained without heating. 3. The protein concentration of the whey protein-containing solution containing a metal element is 0.05 to that of the whey protein-containing solution.
The proteinaceous microparticle according to claim 1, which is 10% by weight. 4. The proteinaceous microparticle according to claim 1, wherein the metal element is derived from the added metal salt. 5. The proteinaceous microparticle according to claim 1, wherein the metal element is derived from the added natural mineral material. 6. The proteinaceous microparticles according to claim 5, wherein the natural mineral material is whey mineral or cow bone powder. 7. The proteinaceous microparticle according to claim 6, wherein the natural mineral material is whey calcium. 8. The proteinaceous microparticle according to claim 1, wherein the acid is hydrochloric acid, sulfuric acid, lactic acid, acetic acid or phosphoric acid. 9. The proteinaceous microparticle according to claim 1, wherein the pH is raised to 6 to 9 after removing the insoluble matter. 10. The proteinaceous microparticles according to claim 1, wherein the hydrophilic organic solvent is used in an amount of 0.3 times or more (v / v) with respect to the whey protein-containing solution. 11. The hydrophilic organic solvent is one having 1 to 5 carbon atoms.
The proteinaceous microparticle according to claim 1, which is a polyhydric or polyhydric alcohol. 12. The proteinaceous microparticle according to claim 1, wherein the hydrophilic organic solvent is ethanol. 13. A liquid containing whey protein containing a metal element
Instead of lowering the pH with acid to remove insolubles,
The proteinaceous fine particles according to claim 1, wherein acid whey is used. 14. The proteinaceous fine particles according to claim 13, wherein the protein in the acid whey is 0.05 to 10% by weight based on the acid whey. 15. A liquid containing whey protein containing a metal element
The method according to claim 1, which is obtained by lowering pH with an acid to remove insolubles, separating the insolubles generated by increasing pH, and mixing the separated supernatant with a hydrophilic organic solvent. Proteinaceous microparticles. 16. A whey protein-containing liquid containing a metal element
A method for producing proteinaceous microparticles, which comprises reducing pH with an acid to remove insoluble matter, then increasing pH, and further mixing with a hydrophilic organic solvent. 17. The method according to claim 16, which is carried out without heating. 18. A protein concentration in a whey protein-containing solution containing a metal element is 0.0 with respect to that of the whey protein-containing solution.
The method according to claim 16, which is 5 to 10% by weight. 19. The method according to claim 16, wherein the protein concentration of the acid whey is from 0.05 to 10% by weight based on the acid whey. 20. A whey protein-containing liquid containing a metal element
17. The pH is lowered with an acid to remove insoluble matter, the pH is increased, the resulting insoluble matter is separated, and the supernatant after the separation is mixed with a hydrophilic organic solvent. Manufacturing method.