JP2002315506A - Method for producing whey mother liquid powder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing whey mother liquid powder containing only milk calcium as calcium, reduced with mono-valent ions such as sodium, chlorine, potassium, etc., easy for drying and hard to absorb moisture. SOLUTION: This method for producing the whey mother liquid powder is characterized by performing a nano-filtration of a filtrate obtained by an ultra-filtration of whey or skim milk, concentrating, holding for a prescribed time under cooling, removing deposited lactose, re-concentrating, adding lactose crystal under cooling, further holding for a prescribed time under cooling, precipitating the lactose crystal and then drying the concentrated liquid containing the above lactose crystal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a whey mother liquid powder produced by recovering and removing most of protein and lactose from whey or skim milk obtained by removing fat and casein from mammalian milk. The present invention relates to a method for producing whey mother liquid powder which is useful as a mineral source for human food and animal feed.

More specifically, the present invention relates to a nanofiltration of a permeate obtained by ultrafiltration of whey or skim milk, concentration, holding for a certain time under cooling, removal of lactose precipitated, reconcentration, and cooling. Lactose crystals are added underneath and further kept under cooling for a certain time,
The present invention relates to a method for producing whey mother liquid powder, which comprises precipitating lactose crystals and drying a concentrated liquid containing the lactose crystals. In the present specification, the percentage (%) is
Unless otherwise specified, it is indicated by weight.

[0003]

2. Description of the Related Art Conventionally, milk of mammals, such as cows and goats, is excellent as a nutritional food, and has been used by mankind for a long time as it is for drinking as it is or as fermented products such as cheese and yogurt. Milk contains various nutrients, and among them, mineral components (hereinafter sometimes referred to as milk minerals) contain all essential minerals in a well-balanced manner, including trace amounts of essential minerals. On the other hand, whey (whey) produced as a by-product of cheese production is inferior in storability and further unpleasant in flavor, so it is not suitable for edible use as is, and is mostly used as feed for livestock or discarded. I was

[0004] However, whey contains most of whey proteins and milk minerals. In recent years, whey proteins in whey have been separated due to advances in membrane separation technology, and are widely used as food materials. Research has also been conducted on the effective use of milk minerals in whey.

[0005] As a method of using milk minerals, a method of removing whey protein and lactose and forming a concentrate or drying the concentrate to form a powder has been conventionally performed. As a technique, for example, curd (complex coagulate of casein and lipid) generated by adding an organic acid to raw milk is removed, the obtained acidic whey is subjected to ultrafiltration, and an organic acid is added to the permeate. The pH is adjusted to 3.0 or less, the concentrate is concentrated, cooled to remove precipitated lactose, and concentrated to produce a milk mineral concentrate (JP-B-62-318).
No. 90) is known.

However, this method uses expensive raw milk as a raw material, and not only does the resulting milk mineral concentrate become expensive, but the milk mineral content in the obtained milk mineral concentrate is as low as about 11%. Furthermore, the milk mineral concentrate is in the form of a syrup, which is inconvenient to handle compared to powder. In addition, as a milk mineral powder that is easier to handle than a syrup-like milk mineral concentrate and a method for producing the same, for example, whey having a pH of 3.5 to 8.5 is subjected to ultrafiltration to remove whey protein and obtain the whey protein. The permeate is concentrated until the concentration of lactose reaches about 50% and the concentrate is
For 10 to 12 hours to remove the precipitated lactose and concentrate to obtain a milk mineral powder (JP-A-63-87945) and a whey mineral obtained by the same method. Concentrate powder (JP-A-63-87)
944) is disclosed.

[0007] However, the milk mineral powder obtained by these conventional techniques is inferior in ease of drying when the concentrated liquid is spray-dried in the production process, and the adhesion of the concentrate to the wall surface of the dryer, cyclone and pneumatic transport. There is a problem that the line is blocked by the concentrate, and the obtained powder has a high hygroscopic property, and there is a problem that the powder is solidified by moisture absorption (hereinafter sometimes referred to as caking).

Further, in addition to the above-mentioned method, the permeate obtained by ultrafiltration of whey is concentrated until the concentration of lactose becomes about 50%, and the lactose precipitated by leaving the concentrated solution to stand is reduced. A method for producing a milk mineral concentrate which is removed and adjusted to a pH of 7 or less and concentrated (Japanese Patent Laid-Open No. 1-191643), and ultrafiltration of whey at pH 4 to 6 with a molecular weight cut off of 40,000 or less. A method for producing a milk mineral concentrate by using an ultrafiltration membrane (JP-A-2-154639) is known.
Even for the milk mineral powders obtained by these conventional techniques, the problem of improving the ease of drying at the time of production and improving the hygroscopicity of the obtained milk mineral powders, that is, the problem of reducing the so-called hygroscopicity, has not been solved. Was.

In order to solve the above-mentioned problem, the present inventors concentrated the permeate obtained by ultrafiltration of whey or a whey concentrate, and kept it for a certain period of time under cooling to remove lactose precipitated. Removed, reconcentrated, added with lactose crystals under cooling, and kept under cooling for a certain time to precipitate lactose crystals, and concentrate the lactose crystals containing at least 2% of the total solid content of the concentrate. 0.0% (by weight) of calcium carbonate was added and dried to develop a method for producing a milk mineral powder which is easy to dry and hardly absorb moisture (Japanese Patent Application Laid-Open No. 6-311).
No. 844. Hereinafter, this is referred to as Conventional Technique 1. ).

[0010]

However, according to the prior art 1, since calcium carbonate needs to be added, calcium which is originally contained in milk minerals, that is, milk which is said to have good absorbability to the body. Calcium (calcium phosphate, calcium citrate, calcium phosphocaseinate, etc.) is undesirable because it contains a large amount of foreign calcium. Further, in the milk mineral powder of the prior art 1, the so-called whey mother liquid powder, the reduction of monovalent ions such as sodium, chlorine, potassium and the like is still insufficient, and further improvement and improvement of the ease of drying during production are obtained. There is room for further improvement in the hygroscopicity of the obtained whey mother liquid powder.

Therefore, there has been a long-awaited demand for a method for producing whey mother liquid powder which contains only milk calcium as calcium, is reduced in monovalent ions such as sodium, chlorine and potassium and is easy to dry and hardly absorbs moisture.

[0012]

Means for Solving the Problems In view of the above-mentioned prior art, the present inventors have conducted intensive studies with the aim of solving the above-mentioned various problems of conventional products, and as a result, have limited whey or skim milk. The ultrafiltration permeate is nanofiltered and concentrated,
Hold under cooling for a certain time, remove lactose that precipitates out, re-concentrate, add lactose crystals under cooling, further keep under cooling for a certain time, precipitate lactose crystals, contain the lactose crystals The method for producing whey mother liquid powder, characterized in that the concentrated liquid is dried, contains only milk calcium as calcium, is reduced in monovalent ions such as sodium, chlorine and potassium, and is easy to dry and absorbs moisture. The present invention was found to be a method capable of producing a difficult whey mother liquid powder, and completed the present invention.

An object of the present invention is to provide a method for producing a whey mother liquid powder which contains only milk calcium as calcium, is reduced in monovalent ions such as sodium, chlorine and potassium and is easy to dry and hard to absorb moisture. It is to be.

According to the present invention, there is provided a method for nanofiltration of a permeate obtained by ultrafiltrating whey or skim milk, concentrating the concentrate, keeping it under cooling for a certain period of time, removing lactose precipitated, and reconcentrating the concentrate. A method for producing whey mother liquid powder, comprising adding lactose crystals under cooling, further holding for a certain period of time under cooling, precipitating lactose crystals, and drying a concentrated liquid containing the lactose crystals. Yes, in the concentration step after nanofiltration, 70-90 ° C at the time of concentration of 10-40% solids
(Hereinafter referred to as Embodiment 1) as a preferred embodiment, and adding a deodorizing / decoloring step before the concentration step after nanofiltration (hereinafter referred to as Embodiment 2). Is described as a preferred embodiment.

[0015]

Next, the present invention will be described in detail. The method for producing whey mother liquid powder which contains only milk calcium as the calcium of the present invention and which is easy to dry and hardly absorbs moisture, in which monovalent ions such as sodium, chlorine and potassium are reduced, is limited to whey or skim milk. The filtered permeate is nanofiltered, concentrated and kept under cooling for a certain period of time to remove lactose which precipitates, reconcentrated, added with lactose crystals under cooling, and further kept under cooling for a certain period of time. And lactose crystals are precipitated, and the concentrated liquid containing the lactose crystals is dried.

The whey used as the starting material of the present invention is obtained by substantially removing fat and casein from mammalian milk, and includes sweet whey, acid whey, which are produced as by-products during cheese production, and these whey. Examples of the skim milk include, for example, skim milk obtained by reducing commercially available skim milk powder (for example, manufactured by Morinaga Milk Products Co., Ltd.).

The raw material whey or skim milk is subjected to ultrafiltration to remove proteins such as whey protein and other precipitates and impurities contained in the whey to obtain a permeate. It is preferred that the raw whey or whey concentrate has a pH of 3.5 to 6.8.

In the ultrafiltration, the molecular weight cut off is 3,000 to 2,000.
It can be carried out by an ultrafiltration device (for example, manufactured by NIRO) equipped with a 000 commercially available ultrafiltration membrane (for example, manufactured by DDS).

The obtained permeate was subjected to a salt rejection of 50 to 8
A nanofiltration device (eg, Filtration) equipped with a 0% nanofiltration membrane (eg, manufactured by Toray Industries, Nitto Denko Corporation, etc.)
Engineering, etc. ) Using nanofiltration, concentration of 2 to 4 times as a solid concentration, desalination to selectively remove monovalent ions such as sodium, chlorine and potassium,
A concentrate (non-permeate) is obtained.

As is clear from the results of the test examples described later, the monofiltration ions such as sodium, chlorine and potassium are removed by the nanofiltration treatment, and a whey mother liquid powder which is easy to dry and hardly absorbs moisture is obtained. Therefore, a nanofiltration treatment is required.

If the nanofiltration treatment is not performed, the drying of the whey mother liquid is inferior. For example, at the time of spray drying, the whey mother liquid adheres to the wall surface of the dryer or the powder in the cyclone and the pneumatic line. And the resulting whey mother liquid powder becomes highly hygroscopic, which causes problems such as caking of the powder.

Further, as is clear from the results of the test examples described later, it is preferable to add a deodorizing / decoloring step after the nanofiltration and before the concentration step, since the flavor is further improved.

The deodorizing and decolorizing steps can be performed by treating with an amphoteric ion exchange resin (for example, KS-35 manufactured by Hokuetsu Carbon Co., Ltd.).

Further, the obtained concentrated liquid (non-permeated liquid) is treated with, for example, an evaporator or the like so that the total solid content is 50%.
As described above, the heat concentration is preferably increased to 50% or more and 65% or less (hereinafter, sometimes referred to as a first concentration step).
When the total solid content of the obtained concentrate is less than 50%, the amount of lactose precipitated in the next cooling step is small, the amount of lactose that can be removed is small, and the milk mineral content in the concentrate can be sufficiently increased. Therefore, the milk mineral content in the finally obtained milk mineral powder cannot be made high. On the other hand, when concentrated to a total solid content of more than 65%, lactose crystals precipitate during the concentration step, making continuous concentration operation on an industrial scale impossible, which is not practical.

As is clear from the results of the test examples described below, the precipitation of calcium phosphate in the concentrated solution in the first concentration step facilitates drying. In the subsequent concentration step, it is preferable to heat and hold, specifically, it is preferable to hold at 70 to 90 ° C. for 20 to 60 minutes when the solid content is 10 to 40%. Furthermore, p of concentrated liquid (non-permeated liquid)
It is preferable to preliminarily adjust H to 6.5 to 8.0 with sodium hydroxide or the like, and then to heat and maintain, since the amount of precipitated calcium phosphate is increased and drying is further facilitated.

The concentrate obtained in the first concentration step (hereinafter, sometimes referred to as the first concentrate) is kept under cooling for a certain period of time to crystallize lactose contained in the first concentrate. Precipitate and remove lactose crystals formed. The cooling temperature of the first concentrate may be a temperature at which the concentrate does not freeze and a temperature at which lactose crystallizes, but is preferably 15 ° C or less, more preferably 10 ° C or less, and more than 15 ° C. At temperatures, lactose crystals do not precipitate efficiently. The longer the cooling time of the first concentrated liquid is, the more preferable it is.
In consideration of the precipitation time of lactose crystals at ° C., the time is preferably 13 hours or more, more preferably 15 hours or more.

Removal of the precipitated lactose crystals can be carried out by a known solid matter separation method, for example, centrifugation with a decanter, filtration with a filter (hereinafter referred to as “first”).
The series of operations from the concentration step to the removal of lactose crystals may be referred to as a lactose crystal removal step. ). In the first concentration step of the lactose crystal removal step, the total solid content is concentrated in the range of 50% or more and 65% or less, and the amount of lactose crystals to be removed from the concentrate is adjusted to obtain the milk mineral obtained. The milk mineral content of the powder can be adjusted to a high concentration. The liquid obtained by this lactose crystal removal step (hereinafter sometimes referred to as a lactose crystal removal liquid) contains a large amount of milk minerals.

Since the total solid content of the lactose crystal-removing solution may be 40% or less as a result of lactose crystal removal, the lactose crystal-removing solution is re-concentrated using, for example, an evaporator (hereinafter, referred to as an evaporator). , The second concentration step). A small amount of lactose crystals was added while cooling the obtained concentrate (hereinafter, sometimes referred to as a second concentrate) as quickly as possible (hereinafter sometimes referred to as a seeding operation). ), Further cooling, and holding for a certain period of time while cooling to generate fine lactose crystals (hereinafter referred to as second
The series of operations including the seeding operation from the concentration step may be referred to as a pre-crystallization step. ).

In the second concentration step, the total solid content of the second concentrated liquid is concentrated to 40% or more, preferably 50% or more, in order to effectively precipitate lactose crystals in the next pre-crystallization step. If the total solid content of the second concentrate is 40% or less, lactose does not sufficiently crystallize in the pre-crystallization step. A seeding operation is performed during the operation of cooling the second concentrated solution. In order to effectively precipitate lactose crystals, the concentrated solution is kept at a temperature of about 10 ° C. or lower by 5 to 5 ° C.
It is preferable to cool as quickly as possible in 480 minutes,
Further, it is preferable that the temperature is maintained at the same temperature for 10 hours or more after reaching 10 ° C. or less. In addition, in order to effectively precipitate lactose crystals, lactose crystals are used in a seeding operation in an amount of 0.02% or more, preferably 0.02% or more based on the weight of the second concentrated liquid.
It is added at a ratio of 2% or more and 1.0% or less. Furthermore, the temperature of the second concentrated liquid when adding lactose crystals is preferably in the range of 35 to 45 ° C.

The whey mother liquid, ie, a milk mineral concentrate containing fine lactose crystals (lactose mineral-containing milk mineral concentrate) obtained in the pre-crystallization step is dried by a known method (for example, spray drying method). Etc.)
The whey mother liquid powder of the present invention is obtained.

When the whey mother liquid is dried without adopting the pre-crystallizing step of the second concentrated liquid, the whey mother liquid is inferior in drying easiness. Cause the clogging of the cyclone and pneumatic line by the powder, and the obtained whey mother liquid powder becomes a highly hygroscopic substance, for example,
Problems such as caking of the powder occur.

According to the method of the present invention described in detail above, whey mother liquid powder which contains milk mineral at a high concentration, is easily dried, and hardly absorbs moisture can be easily produced on an industrial scale.

Next, the present invention will be described in detail with reference to test examples. Test Example 1 This test shows that the method for producing whey mother liquid powder of the present invention is superior to the conventional method for producing milk mineral powder in terms of ease of drying and low hygroscopicity. Made to show. In addition, it was performed to examine the necessity of the nanofiltration process.

(1) Preparation of Samples The following three types of samples were prepared. Sample 1: Whey mother liquid powder of the present invention manufactured by the same method as in Example 1 of the present invention Sample 2: Whey manufactured by the same method as in Example 1 of the present invention except that nanofiltration was not performed Mother Liquid Powder Sample 3: Prior art milk mineral powder produced by the same method as Example 1 of Prior Art 1

(2) Test Method (a) Method of Measuring Sticky Point The sticky point of each sample, which is an index of the ease of drying, was measured as follows. Adjust the water content of the sample to 3%,
The sticky point was measured using a capillary melting point measuring device (manufactured by Japan High Tech Co., Ltd.). A sample with an increased sticky point is a sample with improved ease of drying.

The sticky point is a temperature at which the powder melts and adheres to a wall of a dryer or the like when the powder is heated (Tamayoshi Takano and Tetsuo Taino, “Food Engineering Series Vol. 8, Food Industry” From the bottom of page 219
Line, Kogonshoin, Showa 37).

(B) Method for measuring hygroscopicity The hygroscopicity of each sample was measured as follows. Each sample was weighed in a weighing bottle in an amount of 2 g, and the weighing bottle was left open for 40 hours in an atmosphere with a relative humidity of 60% and a temperature of 37 ° C. with the lid of the weighing bottle opened, and the weight increase A (moisture increase) was measured. It was measured. Based on the above measurement results and the total moisture content B contained in each sample from the beginning of the measurement, the hygroscopicity was represented by the following equation.

C (weight percentage indicating hygroscopicity) = A / B ×
100

The smaller the value of C, the harder it is to absorb moisture.

(3) Test Results The results of this test are as shown in Table 1. As is clear from Table 1, the sample 1 of the present invention has a higher sticky point and a smaller weight percentage indicating hygroscopicity, and thus is easier to dry and has lower hygroscopicity than the sample 3 of the prior art. It turned out to be excellent. Further, the whey mother liquid powder of the present invention does not contain calcium carbonate,
It is also excellent in that it contains only milk calcium as calcium.

Also, as compared with Sample 2 which was not subjected to nanofiltration, Sample 1 of the present invention has a higher sticky point and a smaller weight percentage indicating hygroscopicity, and therefore, is easier to dry and has a lower hygroscopicity. It has been found that a nanofiltration step is required to produce a mother liquid powder.

In the range of the salt rejection of 50 to 80%,
Tests were conducted by appropriately changing the type of the nanofiltration membrane, and almost the same results were obtained.

[0043]

[Table 1]

Test Example 2 In this test, the conditions of proper heating and holding in the first concentration step (concentration (solid content) of the concentrated liquid during the heating and holding treatment in the first concentration step) were determined using the sticky point and the hygroscopicity as indices.
Condition).

(1) Preparation of Samples The following four types of samples were prepared. Sample 4: Example 2 of the present invention, except that the concentration (solid content) of the concentrated liquid during the heat holding treatment in the first concentration step was 5%.
Sample 5: Example 2 of the present invention, except that the concentration (solid content) of the concentrated solution during the heat-holding treatment in the first concentration step was 10%. Sample 6: Example 2 of the present invention except that the concentration (solid content) of the concentrated liquid during the heat-holding treatment in the first concentration step was 40%. Sample 7: Example 2 of the present invention, except that the concentration (solid content) of the concentrated liquid during the heat-holding treatment in the first concentration step was set to 50%. Whey mother liquid powder of the present invention produced by the same method as above

(2) Test Method The measurement of the sticky point and the measurement of the hygroscopicity were performed by the same method as the test method of Test Example 1.

(3) Test Results The results of this test are as shown in Table 2. As is clear from Table 2, when the solid content of the concentrated liquid at the time of the heating and holding treatment in the first concentration step is 10 to 40%, the sticky point is higher, and the weight percentage indicating hygroscopicity is further reduced. In order to produce a whey mother liquid powder which is easy to dry and has low hygroscopicity, a solid content of 10 to 4% is required.
It has been found that it is preferable to carry out the heat-holding treatment at the time of concentration of 0%.

The test was carried out by appropriately changing the heating temperature and the holding time within the range of 70 to 90 ° C. and 20 to 60 minutes among the conditions of the heating and holding, and almost the same results were obtained.

[0049]

[Table 2]

Test Example 3 This test was conducted to examine the proper conditions for heating and holding (heating temperature and holding time) in the first concentration step using the sticky point and hygroscopicity as indices.

(1) Preparation of Samples The following eight types of samples were prepared. Sample 8: Whey mother liquid powder of the present invention manufactured by the same method as in Example 2 of the present invention except that the heating temperature was set to 60 ° C Sample 9: The present invention except that the heating temperature was set to 70 ° C Sample 10: Whey mother liquid of the present invention manufactured by the same method as in Example 2 of the present invention except that the heating temperature was 90 ° C. Liquid powder Sample 11: Except that the heating temperature was set to 100 ° C., except that the whey mother liquid powder of the present invention manufactured by the same method as in Example 2 of the present invention Sample 12: Except that the holding time was set to 10 minutes, Whey mother liquid powder of the present invention produced by the same method as in Example 2 of the present invention Sample 13: The same method as in Example 2 of the present invention except that the retention time was set to 20 minutes. Sample 14: Whey mother liquid powder of the present invention manufactured by the same method as in Example 2 of the present invention except that the holding time was set to 60 minutes. Whey mother liquid powder of the present invention produced by the same method as in Example 2 of the present invention except that the time was 70 minutes.

(2) Test Method The measurement of the sticky point and the measurement of the hygroscopicity were performed by the same method as the test method of Test Example 1. Further, a change in color tone was observed by visual observation.

(3) Test Results The results of this test are as shown in Table 3. As is clear from Table 3, when the heating temperature and the holding time were 70 ° C. or more and 20 minutes or more, the sticky point was higher, and the weight percentage indicating hygroscopicity was further reduced.

The heating temperature or the holding time is 9
If the temperature exceeds 0 ° C. or 60 minutes, browning of the powder product is observed, which is not preferable.

Therefore, in order to produce whey mother liquid powder that is free of browning, easy to dry, and low in hygroscopicity,
It has been found that it is preferable to perform the heat-holding treatment at 70 to 90 ° C. for 20 to 60 minutes.

In the heating and holding conditions, the concentration (solid content) of the concentrated liquid during the heating and holding treatment in the first concentration step is 10 to 4%.
The test was carried out by appropriately changing the range of 0%, but almost the same results were obtained.

[0057]

[Table 3]

Test Example 4 This test was conducted to examine the usefulness of the deodorizing / decoloring step using the flavor as an index.

(1) Preparation of Samples The following two types of samples were prepared. Sample 16: Whey mother liquid powder of the present invention produced by the same method as in Example 2 of the present invention Sample 17: Example 2 of the present invention except that the step of deodorizing and decoloring with an amphoteric ion exchange resin was not performed Whey mother liquid powder of the present invention produced by the same method

(2) Test method The flavor of each sample was tested as follows. Each sample was collected by a panel of 20 men and women from 20 to 40 years old.
The sensory test was performed by the following evaluation method.

Each sample was evaluated on a scale of 0: good taste 1 point: good taste 2 points: good taste 3 points: bad taste 3 points: bad taste, and the average of the evaluation points of each sample was calculated. Slightly good: Less than 5 points: 0.5 or more and less than 1.5 points Slightly poor: 1.5
Not less than 2.5 points and less than 2.5 points: Judgment was made based on the criteria of 2.5 points or more and less than 3.0 points.

(3) Test Results The results of this test are as shown in Table 4. As is clear from Table 4, Sample 1 which was not subjected to the deodorization / decolorization step
Compared with Sample No. 7, Sample 16 of the present invention is superior in flavor, and it has been found that it is preferable to add a deodorizing / decoloring step in order to produce a whey mother liquid powder with further improved flavor. .

The test was carried out by appropriately changing the type of the amphoteric ion exchange resin, and almost the same results were obtained.

[0064]

[Table 4]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

[0066]

Example 1 1000 kg of whey produced as a by-product during the production of Emmental cheese was filtered with an ultrafiltration apparatus equipped with an ultrafiltration membrane (GR61PP, manufactured by DDS) having a molecular weight cutoff of 20,000, and the total solid content was determined. 900 kg of a permeate having a content of 6%, a lactose content of 4.5% and an ash content of 0.4% were obtained. This permeated liquid was concentrated and desalted 2.4 times with a nanofiltration apparatus equipped with a nanofiltration desalination concentration membrane (manufactured by NIRO, membrane type 3838, salt rejection rate 50%), and the solid content was 14.4% (this Ash content
(8%). This concentrated liquid was concentrated to a total solid content of 55% by a batch type concentrator (manufactured by Mizuho),
80.1 kg of a concentrate was obtained.

The concentrate was put into a tank equipped with a cooling jacket, cooled to 8 ° C. with cold water, and kept at the same temperature for 18 hours while stirring. The precipitated lactose crystals were separated by a decanter (manufactured by Westphalia) to obtain 57.1 kg of a concentrated solution having a total solid content of 37.0% and an ash content of 5.2%. The separated lactose crystals were fluid-dried to obtain 23 kg of lactose.

The concentrated liquid from which the lactose crystals had been separated was concentrated to a total solid content of 55% by a batch type concentrator (manufactured by Mizuho) to obtain 38 kg of a concentrated liquid. The concentrate was placed in a tank with a cooling jacket, and cooled with cold water.
Lactose crystals 19 g (0.05% by weight of the concentrate)
%), Cooled to 10 ° C., kept at the same temperature with stirring for 15 hours, and spray-dried by a conventional method to obtain about 20 kg of whey mother liquid powder.

The obtained whey mother liquid powder was tested by the test method described above. As a result, the sticky point, which is an index of the ease of drying when the water content was 3%, was 80 ° C., the relative humidity was 60%, and the humidity was 37 ° C. The hygroscopicity when left in the atmosphere for 40 hours was 280%.

Example 2 500 kg of whey produced as a by-product during the production of Emmental cheese was filtered with an ultrafiltration apparatus equipped with an ultrafiltration membrane (GR61PP, manufactured by DDS) having a molecular weight cutoff of 20,000, and the total solid content was determined. 450 kg of permeate having 6%, lactose content 4.5% and ash content 0.4% were obtained. This permeated liquid was concentrated and desalted 2.4 times with a nanofiltration apparatus equipped with a nanofiltration desalination concentration membrane (manufactured by NIRO, membrane type 3838, salt rejection rate 50%), and the solid content was 14.4% (this Ash content
187 kg of a desalted concentrate (8%).

The desalted concentrate was passed through an ion-exchange resin tower filled with an amphoteric ion-exchange resin (KS-35, manufactured by Ajinomoto Fine-Techno Co., Inc.), and decolorized and deodorized.

Next, this decolorizing / deodorizing / desalting concentrated solution (pH
5.8), 2% sodium hydroxide was added to adjust the pH to 7.
Adjusted to zero. Further, the concentrate is heated to 80 ° C.
This temperature was maintained for 30 minutes to cause precipitation of calcium phosphate.

This concentrated solution was concentrated to a total solid content of 55% by a batch-type concentrator (manufactured by Mizuho Co., Ltd.).
0 kg was obtained.

The concentrate was placed in a tank equipped with a cooling jacket, cooled to 7 ° C. with cold water, and kept at the same temperature for 24 hours while stirring. The precipitated lactose crystals were separated by a decanter (manufactured by Westphalia) to obtain 34.9 kg of a concentrated solution having a total solid content of 37.0% and an ash content of 5.4%. Separated lactose crystals were fluid-dried to obtain 14 kg of lactose.

The concentrated liquid from which the lactose crystals were separated was concentrated to a total solid content of 55% by a batch type concentrator (manufactured by Mizuho) to obtain 23 kg of a concentrated liquid. The concentrate was placed in a tank with a cooling jacket, and cooled with cold water.
Lactose crystals (0.05 g of concentrated liquid weight)
%), Cooled to 8 ° C, and stirred at the same temperature for 1 hour.
The mixture was kept for 5 hours and spray-dried by a conventional method to obtain about 12 kg of whey mother liquid powder.

The obtained whey mother liquid powder was tested by the test method described above. As a result, the sticky point, which is an index of the ease of drying when the water content was 3%, was 90 ° C., the relative humidity was 60%, and the humidity was 37 ° C. When left in the atmosphere for 40 hours, the hygroscopicity was 224%, and the flavor was good.

[0077]

As described above in detail, the present invention provides a nanofiltration of a permeate obtained by ultrafiltration of whey or skim milk, concentration, and holding for a certain period of time under cooling to remove precipitated lactose.
Reconcentrating, adding lactose crystals under cooling, further holding for a certain period of time under cooling to precipitate lactose crystals, and drying the concentrated liquid containing the lactose crystals, the whey mother liquid powder characterized in that The present invention relates to a manufacturing method, and the effects achieved by the present invention are as follows. 1) The method for producing a whey mother liquid powder of the present invention comprises:
A whey mother liquid powder containing only milk calcium as calcium and reducing monovalent ions such as sodium, chlorine and potassium can be produced. 2) The method for producing whey mother liquid powder of the present invention comprises:
A whey mother liquid powder that is easy to dry during production and hardly absorbs moisture can be easily produced on an industrial scale.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2B150 BA03 BD06 CC12 CC13 4B001 AC06 BC04 EC09 4B018 LE03 MD01 MD71 ME14

Claims (3)

[Claims] 1. The permeate obtained by ultrafiltration of whey or skim milk is subjected to nanofiltration, concentrated, kept under cooling for a certain time, lactose precipitated is removed, reconcentrated, and lactose crystals are collected under cooling. A method for producing whey mother liquid powder, which comprises adding lactose crystals for a certain period of time under cooling, precipitating lactose crystals, and drying a concentrated liquid containing the lactose crystals. 2. In the concentration step after the nanofiltration, when the solid content is 10 to 40% by weight, the concentration is 20 to 70.degree.
The method for producing a whey mother liquid powder according to claim 1, wherein the whey mother liquid powder is held for 1 to 60 minutes. 3. The method according to claim 1, wherein a deodorizing / decoloring step is added after the nanofiltration and before the concentration step.
The method for producing a whey mother liquid powder according to the above.