阅读说明：本技术 奶渣中稀奶油的精炼工艺 (Refining process of dilute cream in milk residue ) 是由 宋礼 罗丽 崔广智 苏德亮 于 2020-07-07 设计创作，主要内容包括：本发明涉及奶制品加工技术领域,尤其是涉及一种奶渣中稀奶油的精炼工艺。奶渣中稀奶油的精炼工艺,包括如下步骤：(a)奶渣溶液离心处理,收集稀奶油；(b)所述稀奶油于80～90℃进行碱炼处理,收集上层清油；(c)采用食盐水对所述清油进行水洗处理,将所述水洗处理后的清油进行脱水处理、脱色处理；(d)将所述脱色处理后的物料进行除杂处理,得到精炼稀奶油。采用本发明的精炼处理方法,能够提升稀奶油的纯度和滋气味,精炼后的稀奶油可以作为寺庙酥油灯和化工产品肥皂的原料等使用,既解决了稀奶油污染环境的问题,又提高了奶渣的原料利用率,增加经济效益。(The invention relates to the technical field of dairy product processing, in particular to a refining process of cream in milk residues. The refining process of the cream in the milk residue comprises the following steps: (a) centrifuging the milk residue solution, and collecting the cream; (b) performing alkali refining on the cream at 80-90 ℃, and collecting upper clear oil; (c) washing the clear oil with salt water, and dehydrating and decoloring the washed clear oil; (d) and removing impurities from the decolored material to obtain the refined cream. By adopting the refining treatment method, the purity and the taste of the cream can be improved, and the refined cream can be used as raw materials of a temple butter lamp, a chemical product soap and the like, so that the problem of environmental pollution caused by the cream is solved, the raw material utilization rate of the milk residue is improved, and the economic benefit is increased.)

1. The refining process of the cream in the milk residue is characterized by comprising the following steps:

(a) centrifuging the milk residue solution, and collecting the cream;

(b) performing alkali refining on the cream at 80-90 ℃, and collecting upper clear oil;

(c) washing the clear oil with salt water, and dehydrating and decoloring the washed clear oil;

(d) and removing impurities from the decolored material to obtain the refined cream.

2. A process for refining cream in milk creamer according to claim 1, characterized in that said preparation of said milk creamer solution comprises: mixing the milk residues with a sodium hydroxide aqueous solution, and stirring at 50-60 ℃ to fully dissolve the milk residues;

preferably, the mass fraction of the sodium hydroxide aqueous solution is 6-8%;

preferably, in the milk residue solution, the amount of the milk residues is 5-7% of the mass of the milk residue solution.

3. A refining process of cream in milk residue as claimed in claim 1, wherein the temperature of the centrifugal treatment is 50-65 ℃, and the rotation speed of the centrifugal treatment is 6000-7000 rpm.

4. A process for refining cream of creme in milk residues according to any of claims 1 to 3, wherein in step (b), said alkali refining comprises: and adding sodium hydroxide into the cream at 80-90 ℃ under stirring to enable the pH to reach 12-13, continuously stirring for 5-10 min, and standing for more than 4 h.

5. A refining process of cream in milk residue as claimed in claim 1, wherein in step (b), the cream is left standing for more than 4h at 80-90 ℃ and pH of 13, and the clear oil on the upper layer is collected.

6. A process for refining cream of creme in milk residues according to any of claims 1 to 3, wherein in step (b), said alkali refining comprises: adding anhydrous sodium sulfate into the cream at 80-90 ℃ under stirring to enable the pH to reach 12-13, continuously stirring for 5-10 min, and then standing for more than 4 h;

preferably, the amount of the anhydrous sodium sulfate is 8-10% of the mass of the cream.

7. A refining process of cream in milk residue as claimed in claim 1, wherein the mass fraction of the salt solution is 8% -12%;

preferably, the operation of the water washing treatment comprises: mixing the clear oil and the salt solution, stirring for 1-3 min, and collecting an oil layer;

preferably, the temperature of the clear oil and the salt water is 70-80 ℃.

8. A refining process of cream in milk residues according to claim 1 or 7, characterized in that said water washing treatment comprises a primary water washing treatment and a secondary water washing treatment;

in the primary water washing treatment, the using amount of the salt solution is 18-22% of the weight of the clear oil;

in the secondary water washing treatment, the using amount of the salt solution is 8-12% of the weight of the clear oil.

9. A process for refining cream in milk creamer according to claim 1, characterized in that said dehydration treatment comprises vacuum dehydration;

preferably, the vacuum dehydration conditions include: dehydrating at 60-70 ℃ under vacuum.

10. A refining process of cream in milk residues according to claim 1, characterized in that the decolorization treatment comprises activated carbon decolorization treatment;

preferably, the activated carbon decolorization treatment includes: mixing the boiled oil and the activated carbon, and stirring and decoloring under the conditions of vacuum and 95-100 ℃;

preferably, the using amount of the activated carbon is 0.5-1% of the mass of the clear oil;

preferably, a diatomite filter is adopted to carry out impurity removal treatment on the decolored material.

Technical Field

The invention relates to the technical field of dairy product processing, in particular to a refining process of cream in milk residues.

Background

The "Qula" is the transliteration of Tibetan language, which is the milk residue obtained by boiling and cooling yak skim milk separated from cream by a herdsman in the Tibet plateau, inoculating lactobacillus for fermentation and acidification to solidify milk protein, separating whey, and dehydrating and drying. The trala is a traditional food for herdsmen for thousands of years, is closely related to the production and life of the herdsmen, and has become one of the symbols of traditional culture of Tibetan. With the development of the economic level and the scientific technology, the triton is not only eaten as daily food for herdsmen, but also is widely processed and applied as a raw material for casein processing. The milk residue is a main raw material for producing casein and caseinate in China, and with the increase of market demands of the casein, the caseinate and derivative products, the market demands of the milk residue show a better development trend. By preliminary estimation, at present, the total amount of national milk residue resources is about 3 ten thousand tons, wherein the total amount of the national milk residue resources is about 2 ten thousand tons for production flow, and the rest 1 ten thousand tons are reserved for herdsmen to eat.

Due to the influence of the manufacturing process and the storage condition, the oxidation and the putrefaction of milk fat in the milk residue are serious, the taste is bad, and in the production process of casein and caseinate, the dilute cream in the milk residue is centrifugally separated and is treated as waste together with impurities (such as cow hair, pasture, stones and the like) in the milk, so that the environment is polluted, the wastewater treatment pressure is increased, and the utilization rate of milk residue resources is reduced.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

The invention aims to provide a refining process of cream in milk residues, which aims to solve the technical problems of poor flavor of the milk residues, low utilization rate of milk residue resources and the like in the prior art.

In order to achieve the above purpose of the present invention, the following technical solutions are adopted:

the refining process of the cream in the milk residue comprises the following steps:

(a) centrifuging the milk residue solution, and collecting the cream;

(b) performing alkali refining on the cream at 80-90 ℃, and collecting upper clear oil;

(c) washing the clear oil with salt water, and dehydrating and decoloring the washed clear oil;

(d) and removing impurities from the decolored material to obtain the refined cream.

In a specific embodiment of the present invention, the step (a) further comprises collecting the solution after the centrifugal treatment of the milk residue solution. The solution after centrifugation can be used for preparing casein and the like by a casein preparation process.

The milk residue solution is subjected to centrifugal treatment, and the solution obtained through centrifugal treatment can be directly used for preparing casein and the like through a casein preparation process; the refining method of the invention is adopted for the cream obtained by centrifugal treatment, the purity and the taste of the cream can be improved, and the refined cream can be used as the raw materials of a temple butter lamp and a chemical product soap, so that the problem of environmental pollution caused by the cream is solved, the raw material utilization rate of the milk residue is improved, and the economic benefit is increased.

The cream oil in the milk residue is separated by centrifugal treatment, and the refining of the cream is realized by the processes of alkali addition for refining, water addition for cleaning, dehydration, decoloration, impurity removal and the like, the fat content of the final product can reach more than 99 percent, and the purity and the taste of the cream obtained by extracting the milk residue are ensured.

In a particular embodiment of the invention, the preparation of the milk-pomace solution comprises: and mixing the milk residues with the sodium hydroxide aqueous solution, and stirring at 50-60 ℃ to fully dissolve the milk residues. Further, the mass fraction of the sodium hydroxide aqueous solution is 6% to 8%, preferably 7%. In the milk residue solution, the amount of the milk residues is 5-7% of the mass of the milk residue solution, and is preferably 6%.

In actual operation, the milk residue is dissolved by adopting a food-grade sodium hydroxide aqueous solution.

In a specific embodiment of the invention, the temperature of the centrifugal treatment is 50-65 ℃, and the rotating speed of the centrifugal treatment is 6000-7000 rpm. The centrifugal separation treatment is 5-10 tons/hour, wherein the specification of a centrifugal machine adopted in the centrifugal treatment is RHB-300.

And (3) fully separating the cream in the milk residue solution by adopting the centrifugal treatment conditions.

In practice, the centrifugation may be performed using a disk centrifuge.

In a specific embodiment of the present invention, the alkali refining comprises: adding sodium hydroxide into the cream at 80-90 ℃ under stirring to enable the pH to reach 12-13, continuously stirring for 5-10 min, and then standing for more than 4 h;

alternatively, the alkali refining comprises: adding anhydrous sodium sulfate into the cream at 80-90 ℃ under stirring to enable the pH to reach 12-13, continuously stirring for 5-10 min, and then standing for more than 4 h; wherein the amount of the anhydrous sodium sulfate is 8-10% of the mass of the cream.

In a preferred embodiment of the present invention, in the step (b), the cream is allowed to stand at 80 to 90 ℃ and pH 13 for 4 hours or more, and the clear oil on the upper layer is collected.

In practical operation, the obtained upper layer clear oil can be collected in an upper layer oil absorption mode for subsequent treatment.

In a specific embodiment of the present invention, the saline solution is 8% to 12%, preferably 10% by mass.

In a specific embodiment of the present invention, the operation of the water washing treatment comprises: and mixing the clear oil and the salt solution, stirring for 1-3 min, and collecting an oil layer. Further, the temperature of the clear oil and the salt water is 70-80 ℃.

In a specific embodiment of the invention, the salt water is added to the boiled oil by spraying. The salt water is fully contacted with the clear oil by the mode, and impurities are removed by washing.

In a preferred embodiment of the present invention, the water washing treatment includes a primary water washing treatment and a secondary water washing treatment;

in the primary water washing treatment, the using amount of the salt solution is 18-22% of the weight of the clear oil, and the preferable amount is 20%;

in the secondary water washing treatment, the using amount of the salt solution is 8-12% of the weight of the clear oil, and the using amount of the salt solution is preferably 10%.

In a particular embodiment of the invention, the dehydration treatment comprises vacuum dehydration. Further, the vacuum dehydration comprises: dehydrating at 60-70 ℃ under vacuum.

In a specific embodiment of the present invention, the decoloring treatment includes activated carbon decoloring treatment. Further, the activated carbon decolorization treatment includes: mixing the boiled oil and the activated carbon, and stirring and decoloring under vacuum at 95-100 ℃. Furthermore, the amount of the activated carbon is 0.5 to 1 percent of the mass of the clear oil, such as 1 percent. Preferably, the time of the decoloring treatment is 30-60 min.

In a specific embodiment of the invention, a diatomite filter is adopted to carry out the impurity removal treatment on the decolored material. Impurities in the cream can be removed by a diatomite filter.

Compared with the prior art, the invention has the beneficial effects that:

(1) the milk residue solution is subjected to centrifugal treatment, and the solution obtained through centrifugal treatment can be directly used for preparing casein and the like through a casein preparation process; the refining method of the invention is adopted for the cream obtained by centrifugal treatment, the purity and the taste of the cream can be improved, and the refined cream can be used as the raw materials of a temple butter lamp and a chemical product soap, so that the problem of environmental pollution caused by the cream is solved, the raw material utilization rate of milk residues is improved, and the economic benefit is increased;

(2) the refining process of the invention adopts the milk residue as the raw material, and the fat content in the dilute cream obtained by refining treatment can reach more than 99 percent.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following detailed description, but those skilled in the art will understand that the following described examples are some, not all, of the examples of the present invention, and are only used for illustrating the present invention, and should not be construed as limiting the scope of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The refining process of the cream in the milk residue comprises the following steps:

(a) centrifuging the milk residue solution, and collecting the cream;

(b) performing alkali refining on the cream at 80-90 ℃, and collecting upper clear oil;

(c) washing the clear oil with salt water, and dehydrating and decoloring the washed clear oil;

(d) and removing impurities from the decolored material to obtain the refined cream.

In a specific embodiment of the present invention, the step (a) further comprises collecting the solution after the centrifugal treatment of the milk residue solution. The solution after centrifugation can be used for preparing casein and the like by a casein preparation process.

The milk residue solution is subjected to centrifugal treatment, and the solution obtained through centrifugal treatment can be directly used for preparing casein and the like through a casein preparation process; the refining method of the invention is adopted for the cream obtained by centrifugal treatment, the purity and the taste of the cream can be improved, and the refined cream can be used as the raw materials of a temple butter lamp and a chemical product soap, so that the problem of environmental pollution caused by the cream is solved, the raw material utilization rate of the milk residue is improved, and the economic benefit is increased.

The cream oil in the milk residue is separated by centrifugal treatment, and the refining of the cream is realized by the processes of alkali addition for refining, water addition for cleaning, dehydration, decoloration, impurity removal and the like, the fat content of the final product can reach more than 99 percent, and the purity and the taste of the cream obtained by extracting the milk residue are ensured.

In a particular embodiment of the invention, the preparation of the milk-pomace solution comprises: and mixing the milk residues with the sodium hydroxide aqueous solution, and stirring at 50-65 ℃ to fully dissolve the milk residues. Further, the mass fraction of the sodium hydroxide aqueous solution is 6% to 8%, preferably 7%. In the milk residue solution, the amount of the milk residues is 5-7% of the mass of the milk residue solution, and is preferably 6%. As in the different embodiments, the temperature of mixing and stirring can be 50 deg.C, 55 deg.C, 60 deg.C, 65 deg.C, etc.

In actual operation, the milk residue is dissolved by adopting a food-grade sodium hydroxide aqueous solution.

In a specific embodiment of the invention, the grain size of the milk residues is 30-90 meshes. Specifically, the milk residue raw material is ground to a particle size of 30-90 meshes, and then a milk residue solution is prepared subsequently.

In a specific embodiment of the invention, the temperature of the centrifugal treatment is 50-65 ℃, and the rotating speed of the centrifugal treatment is 6000-7000 rpm.

And (3) fully separating the cream in the milk residue solution by adopting the centrifugal treatment conditions.

In practice, the centrifugation may be performed using a disk centrifuge. The centrifugal separation treatment is 5-10 tons/hour, wherein the centrifugal treatment adopts a centrifugal machine with the specification of RHB-300.

In a specific embodiment of the present invention, the alkali refining comprises: adding sodium hydroxide into the cream at 80-90 ℃ under stirring to enable the pH to reach 12-13, continuously stirring for 5-10 min, and then standing for more than 4 h;

alternatively, the alkali refining comprises: adding anhydrous sodium sulfate into the cream at 80-90 ℃ under stirring to enable the pH to reach 12-13, continuously stirring for 5-10 min, and then standing for more than 4 h; wherein the amount of the anhydrous sodium sulfate is 8-10% of the mass of the cream.

In a preferred embodiment of the present invention, in the step (b), the cream is allowed to stand at 80 to 90 ℃ and pH 13 for 4 hours or more, and the clear oil on the upper layer is collected.

In practical operation, the obtained upper layer clear oil can be collected in an upper layer oil absorption mode for subsequent treatment.

In a specific embodiment of the present invention, the saline solution is 8% to 12%, preferably 10% by mass.

In a specific embodiment of the present invention, the operation of the water washing treatment comprises: and mixing the clear oil and the salt solution, stirring for 1-3 min, and collecting an oil layer. Further, the temperature of the clear oil and the salt water is 70-80 ℃.

In a specific embodiment of the invention, the salt water is added to the boiled oil by spraying. The salt water is fully contacted with the clear oil by the mode, and impurities are removed by washing.

In a preferred embodiment of the present invention, the water washing treatment includes a primary water washing treatment and a secondary water washing treatment;

in the primary water washing treatment, the using amount of the salt solution is 18-22% of the weight of the clear oil, and the preferable amount is 20%;

in the secondary water washing treatment, the using amount of the salt solution is 8-12% of the weight of the clear oil, and the using amount of the salt solution is preferably 10%.

In a particular embodiment of the invention, the dehydration treatment comprises vacuum dehydration. Further, the vacuum dehydration comprises: dehydrating at 60-70 ℃ under vacuum.

In a specific embodiment of the present invention, the decoloring treatment includes activated carbon decoloring treatment. Further, the activated carbon decolorization treatment includes: mixing the boiled oil and the activated carbon, and stirring and decoloring under vacuum at 95-100 ℃. Furthermore, the amount of the activated carbon is 0.5 to 1 percent of the mass of the clear oil, such as 1 percent. Preferably, the time of the decoloring treatment is 30-60 min.

In a specific embodiment of the invention, a diatomite filter is adopted to carry out the impurity removal treatment on the decolored material. Impurities in the cream can be removed by a diatomite filter.

The fat content in the cream obtained by the refining process can reach more than 99 percent, and the pressure of sewage treatment can be reduced and the environmental pollution can be reduced after the cream is recycled.