JPS6121053B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a milk processing method for obtaining casein, milk curd for cheese, and whey using decationized milk obtained by treatment with a cation exchange resin. Previously known methods for producing casein and milk curd for cheese production without using rennet include milk pH
A method for coagulating casein in milk by lowering the isoelectric point of casein to about 4.6 is included. Lowering milk pH and coagulation can be achieved by lactic acid fermentation of milk, but it is necessary to store a large amount of milk during the entire fermentation period, which takes 12 to 16 hours. It is also possible to coagulate the casein in the milk by acidifying the milk by adding strong mineral or organic acids (e.g., hydrochloric acid, sulfuric acid, or especially lactic acid) to reduce the milk pH to the isoelectric point of milk casein. I can do it even if I have to. This acid addition method yields casein of good quality, but at the same time produces a strongly mineralized whey with a high acid content, which is difficult to stabilize as such. Therefore, in many cases
Furthermore, demineralization treatments using ion exchange resins or electrodialysis are required, and furthermore, treatment of the milk with strong acids can change the properties of the milk and destroy certain useful components in the milk. It can also be carried out by passing the milk through a layer of acidic cation exchange resin, replacing the cations in the milk with hydrogen ions, and precipitating the milk casein on the particles of the resin. This method yields casein of good quality and whey with high food value. However, precipitation of casein onto the resin particles creates the problem of rapid inactivation of the resin. In order to solve this problem, European Patent Application Publication No. 0004231 proposes the following two-step method. That is, in the first step, the milk is contacted with a cation exchange resin to lower its pH to a value higher than the isoelectric point of milk casein, for example to a value not lower than 4.7, especially 4.9-5. This avoids agglomeration of the milk casein which causes sequestration of the ion exchange resin particles. In the second step, a dilute acid is added to the milk thus treated to acidify it to a pH of 4.6, which is the isoelectric point of milk casein, coagulate the casein, and separate it. However, the acidification of the milk by this second step of acid addition can corrode the equipment used and still produces highly mineralized acidic whey, which requires costly total or partial dehydration for commercialization. Requires mineralization. Furthermore, in French Patent Application No. 2331963, skimmed milk is concentrated by ultrafiltration to obtain a milk concentrate and a milk ultraliquid, and the pH of the milk ultraliquid is changed to a cation exchange resin from a normal pH of 4.3 to 4.8 (eg, pH 1-2.5) and added to the milk concentrate to precipitate casein from the concentrate. The milk concentrate is milk rich in casein and soluble protein (17-19 g in 100 g of the concentrate, compared to 3-3.2 g in 100 g of normal milk). Milk ultrafluid contains soluble components in milk as essential components, namely lactose, soluble mineral salts (ultramilk ultrafluid)
0.45-0.48g per 100g) and non-protein nitrogen-containing substances (0.12-0.18g per 100g of ultrafluid). This is whey that does not contain proteinaceous nitrogen-containing substances. Since the milk ultrafluid does not contain casein and proteinaceous nitrogen-containing substances, treatment with a cation exchange resin does not result in precipitation of these substances on the resin particles. However, it has the composition of cheese with whey separated. and to obtain a milk concentrate from which cheese can be made without a whey separation step.
Concentrating milk by ultrafiltration requires technology that requires high investment and high running costs. In addition, when coagulating casein from milk concentrate, it is necessary to add a large amount of milk ultrafluid whose pH has been lowered with a cation exchange resin (it is difficult to remove), and all of the concentration by ultrafiltration is required. The benefits of this will be nullified. Additionally, the liquid used (milk concentrate + milk ultrafluid)
Considering that the amount of milk concentrate is more than twice the amount of milk concentrate and that only milk concentrate contains casein to be coagulated, the yield of casein for the liquid used will be very low. The present inventors brought milk into contact with an acid-type cation exchange resin to adjust the milk pH to the isoelectric point of milk casein (PH4.6).
If the mixture of milk and cation exchange resin is kept at a low temperature of 0 to 4 degrees Celsius, casein in the milk may not coagulate, even if the temperature is lowered to room temperature or lower. It has been found that at slightly higher temperatures, milk casein coagulates as soon as it reaches the isoelectric point of casein. We have also developed decationized milk, i.e. mainly , almost free of calcium, sodium and potassium ions, mineral content less than 4g/, Ca/P ratio 0.5
Milk containing all the proteinaceous nitrogen-containing substances and all of the lactose of conventional milk with a pH of 3.8 or less, i.e., lower than the isoelectric point of casein (normal milk has a pH of 6.7), can be obtained. I found out. This acidified decationized milk can be stored for several days without any special precautions at temperatures above 4°C, for example at room temperature, without the casein in it coagulating or bacterial growth. Therefore, it does not require storage at 0 to 4°C). Furthermore, we have found that acidifying normal milk to a desired pH using this acidified decationized milk should be useful in milk processing. In particular, it can be used to economically acidify unprocessed milk, bringing the PH of both milks below the isoelectric point of milk casein in order to coagulate the casein contained in both milks, without rennet. It has been found that acid casein or acid curd as well as whey can be obtained for making cheese. The treatment with cation exchange resins in this process is very economically advantageous, since the treatment with cation exchange resins can be limited to only the amount of milk needed for casein or curd production. Thus, in the present invention, first, acidified decationized milk is obtained using an acid type cation exchange resin without adding any strong mineral acid or organic acid. That is, milk is heated to 0-4°C, preferably 0-4°C.
Contact with a cation exchange resin in acid form at 2° C. for a time necessary to reduce the pH to below 3.8, preferably between 1.5 and 3.8, and then separate the resulting acidified decationized milk from the cation exchange resin. As a result, the decationized milk is obtained. A contact time of 1 to 10 minutes is usually sufficient to achieve the desired pH. This contact time can be shortened by stirring the milk and resin. The volume ratio of milk to be treated and exchange resin is preferably between 5:1 and 15:1.
It is. As the exchange resin, conventional types of acidic cation exchange resins such as those used in conventional demineralization can be used, including those used in whey demineralization. According to the invention, gels or macroporous types (globules, trabeculae, etc.) with sulfonic acid groups, for example
A strongly acidic cation exchange resin having a polystyrene skeleton can be used. Macroporous resins are preferred because they have greater mechanical strength than gels. Strongly acidic cationic resins having a polystyrene skeleton having sulfonic acid groups are commercially available under the following trademarks. Diaprosim-Diamond: Duolite, Rohm and Haas Amberlight
(Rohm and Haas: Amberlite), "Lowatit" (Bayer), "Kastel" (Montedison), "Kastel" (Montedison), "Dowex" (Dow
The following macroporous strong acid type cation exchange resins are preferred. Duolite C26 (styrene-divinylbenzene copolymer with sulfonic acid groups, particle size 0.3-1.2
mm small spherical shape, apparent density 0.85Kg/) Awabarite 200 and Amberlite 252
(Styrene-divinylbenzene copolymer with sulfonic acid groups, particle size 0.4-0.55 mm, apparent density 0.80
Kg/) Lowatite SP112 (polystyrene with sulfonic acid groups, small spherical shape with particle size 0.3-1.5 mm, apparent density
0.70-0.80Kg/) Castel C300P and Castel 300AGRP (styrene-divinylbenzene copolymer with sulfonic acid groups, small particle size of 0.3-1.2 mm, apparent density
0.84-0.86Kg/) Dowex MSC-1 (sulfonated styrene-divinylbenzene copolymer, particle size 0.29-0.84mm)
Small spherical shape, apparent density 0.80Kg/) Milk treated with cation exchange resin is acidified decationized milk (i.e. milk containing only traces of calcium, sodium and potassium ions)
The pH is below 3.8, which is slightly lower than the isoelectric point of casein (normal milk has a pH of about 6.7), and contains all the proteins and lactose contained in normal milk. Its mineral content is less than 4g/Ca/P
The ratio is less than 0.5 (normal milk is 1.3). The treatment of milk with a cation exchange resin can be carried out by methods known per se, such as passing the milk through a fixed bed of cation exchange resin, flowing the milk countercurrently to the cation exchange resin, or passing the milk through a cation exchange resin. The mixture may be stirred mechanically or by the action of air, or by any other suitable method. Once the cation exchange resin is saturated with milk cations, the exchange resin is regenerated with acid. The regenerated resin is washed with decationized water and used for new processing. In the present invention, the acid decationized milk obtained is used to acidify milk and to obtain acid curd and whey for producing cheese without acid milk, casein or rennet. To obtain acidic milk, acid decationized milk is mixed with normal milk to reach the desired PH. To obtain milk casein and whey, acid decationized milk is mixed with a sufficient amount of unprocessed conventional milk to raise the PH of the mixture to near the isoelectric point of milk casein, and then the mixture is Heating at a temperature of ~60°C coagulates the casein in the mixture and separates the coagulated casein and whey. More specifically, acid decationized milk is mixed with a predetermined amount of unprocessed milk (preferably an equal amount of decationized milk) to raise the PH of the mixture to 4.4-4.6; It is heated at a temperature of 50°C to coagulate the casein therein. The coagulated casein is separated from the whey, washed and dried according to conventional methods (spray drying, hot air drying in a fluidized bed, etc.) or treated with alkali metals or alkaline earth metals (sodium, potassium,
Calcium) caseinate or ammonium caseinate. The separated whey (containing only cations from unprocessed milk) can be dried as is or after neutralization, and can be subjected to conventional methods such as demineralization, ultrafiltration, and concentration by reverse osmosis. can be processed. The whey obtained by the present invention has a low mineral content,
The various mineral element ratios are similar to those of the milk used as a raw material, but have the characteristics shown in Table 1 below.

[Table] The whey of the present invention, with or without ultrafiltration concentration, shows good swelling properties and has a higher churning property than any casein whey obtained by direct acidification. It is a surprising fact that it is superior in terms of later capacity and texture. Furthermore, the acid decationized milk according to the present invention,
When used in the production of acid curd for cheese production such as cottage cheese without rennet, the acid decationized milk is mixed with a sufficient amount of untreated milk to bring the pH of the mixture close to the isoelectric point of casein. Usually mixed with milk, the mixture is then heated to 10-60°C to coagulate the casein in the mixture to form a curd, which is cut and heated to a temperature of 48-60°C. Separate the whey and wash the curd with cold water;
Drain well. More specifically, acid decationized milk is mixed with a sufficient amount of unprocessed regular milk (preferably equal to the decationized milk) pre-cooled to 0-4°C, and the pH of the mixture is adjusted to 4.4-4.8. Preferably 4.4~
4.6 and then heated to 30-35°C to solidify and form a curd. This method produces cutlet cheese, queso blanco, quark, cheddar-like cheese, Ricotta cheese,
Cheeses such as blue cheese and pizza cheese can be produced. Next, a method for producing decationized milk and acid curd will be explained using the attached drawings. The attached drawing is a flow sheet schematically showing a specific example of a method for producing decationized milk and acid curd. Skim milk is placed in two raw material tanks 1a and 1b. The milk from either tank is cooled down to 4°C or less with a cooling liquid in a heat exchanger 5 through a pump 2, and then transferred through a pipe 4 to either reaction tank 3a.
Or send to 3b. In the reaction tank 3a or 3b, the milk is brought into contact with a small spherical strong acid type cation exchange resin 6 which is held in suspension in the milk under suitable stirring by a stirrer 7. Measured with PH meter 8
Once the pH has reached the desired value (generally 3.5), the resulting acidified decationized milk is passed through pipe 10 to
It is fed into the storage tank 9 either by gravity alone or by air pressure. The resin particles are retained in the tank 3a or 3b by a sieve 11 located at the bottom of the reaction tank. Pipe the milk remaining between the resin particles into the pipe 12a.
After washing with water sprayed from the spray pipe 12 through the pipe 12b, a dilute solution of hydrochloric acid is sent from the pipe 12b to regenerate the resin particles, and then washed with water. During this regeneration,
Milk processing takes place in the other reaction tank. In the coagulation head 15, the acidic decationized milk stored in the storage tank 9 is combined with the unprocessed milk stored in the tank 1a or 1b (after being cooled in the heat exchanger 5 if necessary) to have a pH of 4.4 to 4.4. They are mixed in a ratio of 4.6. The decationized milk is delivered in a predetermined amount according to a desired pH by a variable delivery pump 13 under the control of a PH meter 14. The steam regulated by the valve 16 is directly transferred to the coagulation head 15.
Coagulation occurs by injecting the Mixture 17
Allow to cool to room temperature and separate the obtained product.
To produce casein, the curd is separated from the whey using a filter 18 provided at the inlet of the first washing tank 29. The whey collected at 20 is subjected to the following processing, and the curds are washed with water sent from 21 and sent via pipe 22 to a second washing tank (not shown). Next, the present invention will be explained in more detail with reference to Examples. Example 1 Production of decationized milk 10 parts (by volume, same hereinafter) of skim milk cooled to 2°C was mixed with a commercially available strong acid type casethion exchange resin (H ⁺ type) having a particle size of 0.3 to 1.2 mm. Mix with 1 part of granular Duolite C26 (a sulfonated styrene-divinylbenzene copolymer with a macroporous structure).
After 5 minutes, separate the milk from the resin. Wash the resin with water and
% hydrochloric acid solution. The analytical values of the obtained decationized milk are shown in Table 2.

[Table] This decationized milk is characterized by a very reduced mineral content and a pH that is clearly below the isoelectric point of milk casein (mineral content is 7.9 g / 3.2g/, pH is 2.3 compared to 6.7 for raw milk). Decationized milk no longer exhibits the white color and milkiness of normal milk, but is a translucent greenish-yellow liquid. This decationized milk does not show any noticeable precipitation after storage for 78 hours at room temperature. Preparation of Casein 10 parts of unprocessed milk are mixed with the decationized milk obtained above. As soon as the PH of the mixture reaches 4.4-4.6, steam is directly bubbled into the mixture and heated to 45°C to coagulate the milk casein. Separate the curd from the whey by sieving. After washing with water, drain the curd, suspend it in 75°C water, and neutralize with 10% NaOH aqueous solution until the final pH is 6.6. The caseinate solution obtained is completely free of impurities. After spray drying, a white powder of sodium caseinate is obtained. The flavor of this caseinate is neutral and natural. The analytical values of the washed curd, the resulting casenate and whey are shown in Table 3.

[Table] Example 2 Production of decationized milk One part of H ⁺ type cation exchange resin, Duolite C26 (a cation exchange resin with a polystyrene skeleton having a sulfonic acid functional group, small spherical powder with a diameter of 0.3 to 1.2 mm) was heated at 2°C. Pack into a temperature-controlled double-walled column. 10 parts of skimmed milk are cooled to 2° C. and decationized by countercurrent flow against the resin at a rate of 5 parts/hour, and the decationized milk is then recovered. The analytical values are shown in Table 4.

[Table] This decationized milk has a reduced mineral content (3.5g/ compared to 8.25g/ of raw milk) and a pH below the isoelectric point (2.4 compared to 6.7 of raw milk). characterized. Preparation of Casein One part decationized milk is mixed with one part unprocessed milk. The PH of the mixture is 4.5. Add this mixing part to 30~
Coagulate the casein by heating to 60°C (eg, 50°C). Separate casein from whey, wash and drain. 1.600 kg of curd having the composition shown in Table 5 is obtained from 10 ml of unprocessed milk and 10 ml of decationized milk. Table 5 also shows the composition of the separated whey and, for comparison, the composition of the whey obtained in conventional casein production acidified with hydrochloric acid.

[Table] Casein obtained from 100% milk and 10% water
At 3.1Kg, the amount of milk used per Kg of casein in 10% water is approximately 32. The resulting whey showed a low mineral content (7.25% ash compared to 10.5-12% in whey using hydrochloric acid);
It also has a particularly low chloride content (2.9% compared to 7-7.5% chloride in whey with hydrochloric acid). Example 3 Decationized milk H ⁺ type cation exchange resin (Duolite C26) 1
A portion was packed into a double-walled column temperature-controlled at 2°C.
10 parts of milk cooled to 2°C are decationized by countercurrent flow through the resin at a flow rate of 5 parts/hour, and the decationized milk is then recovered. The analytical values of this decationized milk are shown in Table 6.

[Table] This decationized milk has a low mineral content (3.1g/compared to 7.7g/ of raw milk), and a PH of below the isoelectric point of milk casein (2.2 vs. 6.7 of raw milk). Characterized. Manufacture of casein: Mix 1 part decationized milk with 1 part unprocessed milk.
Set the pH to 4.4. This mixture is heated to 45°C to coagulate the casein. Separate the curd from the whey, wash and drain. Table 7 shows the analytical values of the separated whey. For comparison, the composition of whey obtained by a conventional casein production method in which milk is acidified with hydrochloric acid is also shown.

[Table] The obtained whey has a low mineral content (7.65% ash compared to 10.5-12% ash in whey prepared using hydrochloric acid);
It contains only a small amount of chloride ions (2.85% chloride compared to 7-7.5% in whey with hydrochloric acid). Example 4 Production of neutralized whey The whey obtained in the previous example was neutralized to lower the pH.
5.5 to 6.5. The composition of the neutralized whey is shown in Table 8.

[Table] Example 5 Production of cheese without using rennet Production of decationized milk 1000ml of sterilized skimmed milk cooled to 2°C was stirred.
Particle size of commercially available H ⁺ type strong acid type cation exchange resin
Mix with 0.3-1.2 mm small spherical Deolite C26 (macroporous sulfonated styrene-divinylbenzene copolymer) 100. After 5 minutes, separate the milk from the resin. The resin is washed with water and regenerated with a 10% hydrochloric acid solution. The composition of the obtained decationized milk is shown in Table 9.

[Table] This decationized milk has a very low mineral content and is characterized by a pH clearly lower than the isoelectric point of milk casein (mineral content of raw milk
3.2g/ for 7.9g/, 2.4 for raw milk pH 6.65). This decationized milk no longer exhibits the white emulsion of normal milk, but is a translucent greenish-yellow liquid. This decationized milk does not show any noticeable precipitation even when stored for 48 hours at room temperature. Draining and production of acid curd 1000 ml of sterilized skimmed milk cooled to 2°C is mixed with the decationized milk obtained above. The pH reached 4.4-4.5 and the mixture was slowly heated to 32℃.
The milk protein is heated to a temperature that solidifies it into a curd-like form. Once the resulting curd has reached the appropriate hardness, it is immediately cut. Leave the cut cards for about 15 minutes,
Then warm it up. Gently warm the curd to 52-55°C and hold at that temperature for about 1 hour until the curd reaches the desired hardness. The whey is removed, the curd is washed, cooled in chlorinated water acidified to pH 5.0 (free chlorine 10 mg/), and then drained. This washing and draining operation is repeated several times, and finally, cold water (4 to 5°C) is used. Drain the curd once again to remove excess water. Production of Cheese The drained curd can be packaged with or without salt and can be creamed and treated with salt in a manner known per se. The resulting product has a traditional cottage cheese-like texture and flavor. The composition of the cheese obtained by this method is: dry solids: 22%, protein: 96.00% relative to dry solids.
%, minerals: 2.75% on dry solids, fat: 0.75% on dry solids, lactose: 0.50% on dry solids. The composition of the whey obtained by this method is shown in Table 10. For comparison, the composition of whey obtained by acidification with hydrochloric acid by a conventional method is also shown.

【table】 [Brief explanation of the drawing]

The drawing is a flow sheet showing a specific example of decationized milk production and acid curd production. The main symbols in the drawings have the following meanings. 1
a and 1b...raw material tank, 3a and 3b...
...Reaction tank, 5... Heat exchanger, 6... Cation exchange resin, 8 and 14... PH meter, 15...
Coagulation head.

Claims (1)

[Claims] 1. Having the same protein and lactose content as normal milk,
A milk processing method characterized by mixing normal milk with acid decationized milk having a mineral content of less than 4 g/P, a Ca/P ratio of less than 0.5, and a pH of 3.8 or less, and adjusting the normal milk to a predetermined pH. . 2 (a) Contact the milk with an acid form of a cation exchange resin at 0-4°C for a period sufficient to reduce the pH to below 3.8, separate the resulting decationized milk from the cation exchange resin, and ( b) Mix the decationized milk with a sufficient amount of normal milk so that the pH of the resulting mixture is close to the isoelectric point of milk casein, and heat the mixture to 10 to 60°C to prepare the decationized milk. and a milk processing method characterized by coagulating casein in normal milk and separating the obtained coagulated casein and whey. 3. The milk processing method according to item 2 above, wherein the decationized milk is mixed with enough normal milk to adjust the pH to 4.4 to 4.6. 4. Heat a mixture of decationized milk and regular milk to 40-50℃.
The milk processing method according to item 2 or 3 above, wherein the casein is coagulated by heating to . 5. The milk processing method according to item 2 or 3 above, wherein the mixing volume ratio of decationized milk and normal milk is about 1:1. 6. The milk processing method according to item 2 above, in which whey is obtained by separating coagulated casein. 7. The milk processing method according to item 6 above, wherein the separated whey is neutralized with an alkali metal or alkaline earth metal hydroxide, concentrated, and dried. 8. The milk processing method according to item 2 above, in which milk casein is obtained by separating whey. 9. The milk processing method according to item 8 above, wherein the separated casein is washed with water, drained, and then dried to obtain milk casein. 10 Wash the separated casein with water, drain it,
The milk processing method according to item 8 above, which comprises suspending in hot water, converting into alkali metal, alkaline earth metal or ammonium caseinate, and then drying. 11. The milk processing method according to item 10 above, which involves suspending the milk in hot water at about 75°C. 12 Time required to lower PH from 1.5 to 3.5,
The milk processing method according to item 2 above, wherein milk is brought into contact with a cation exchange resin. 13. The milk processing method according to item 2 above, wherein the cation exchange resin is a strongly acid type cation exchange resin having a polystyrene skeleton having a sulfonic acid group and having a gel-like or macroporous structure. 14 Volume ratio of milk to cation exchange resin 5:1 ~
The milk processing method of item 2 above, wherein the milk is brought into contact with the resin at a ratio of 15:1. 15. The milk processing method according to item 2 above, wherein the milk is cooled to 0 to 2°C and brought into contact with a cation exchange resin. 16. The milk processing method according to item 2 above, wherein the milk to be processed is skimmed milk. 17. The milk processing method according to item 2 above, wherein the milk is brought into contact with the resin by stirring together with the resin, or by passing through or countercurrently flowing through a resin layer. 18 (a) At 0 to 4°C, milk is brought into contact with an acidic cation exchange resin for a sufficient period of time to reduce the pH to 3.8 or less, and the resulting decationized milk is separated from the cation exchange resin; b) mixing the decationized milk with a sufficient amount of normal milk such that the pH of the resulting mixture is around the isoelectric point of milk casein, and (c) heating the mixture to 10-60°C to remove the decationization. A milk processing method characterized by coagulating casein in milk and normal milk into a curd shape, (d) cutting the formed curd and heating at 48 to 50°C to separate the curd and whey. 19. The milk processing method according to item 18 above, wherein the normal milk to be mixed with the decationized milk is cooled in advance to 0 to 4°C. 20. The milk processing method according to item 18 above, wherein the decationized milk is mixed with enough normal milk to adjust the pH to 4.4 to 4.8. 21 Mixture of decationized milk and regular milk at 30 to 35
19. The milk processing method according to item 18 above, which comprises heating to a temperature of 0.degree. C. to form curd. 22 Decationized milk and regular milk in a volume ratio of approximately 1:1
The milk processing method according to the above item 18, wherein the milk processing method is mixed with the above. 23 Separate the whey and wash the curd with cold water.
The milk processing method according to item 18 above, in which milk curd is obtained by draining water. 24. The milk processing method according to item 23 above, wherein the milk curd is a curd for producing cheese without using rennet. 25. The milk processing method according to item 18 above, wherein whey is obtained by separating the curd. 26. The milk processing method according to item 25 above, wherein the separated whey is neutralized with an alkali metal or alkaline earth metal hydroxide, concentrated, and dried. 27 Time required to lower PH from 1.5 to 3.5,
19. The milk processing method of item 18 above, wherein milk is brought into contact with a cation exchange resin. 28. The milk processing method according to item 18, wherein the cation exchange resin is a strongly acid type cation exchange resin having a gel-like or macroporous structure and having a polystyrene skeleton having a sulfonic acid group. 29 Volume ratio of milk to cation exchange resin 5:1 ~
The milk processing method of paragraph 18 above, wherein the milk is brought into contact with the resin at a ratio of 15:1. 30. The milk processing method according to item 18 above, wherein the milk is cooled to 0 to 2°C and brought into contact with a cation exchange resin. 31. The milk processing method according to item 18 above, wherein the milk to be processed is skimmed milk. 32. The milk processing method according to item 18 above, wherein the milk is brought into contact with the resin by stirring together with the resin, or by passing or countercurrently passing through a resin layer.