DE102012220689A1 - Method for reducing the content of sterols in milk and cream - Google Patents

Abstract

Method for reducing cholesterol in milk, which is characterized in that a mixture is produced in a complexing step by stirring or homogenizing milk with cyclodextrin, an insoluble cyclodextrin / cholesterol complex being formed, in a separation step the insoluble cyclodextrin / Cholesterol complex is separated off, whereby a cholesterol-reduced emulsion is obtained and a liquid amylase with food approval is added to the cholesterol-reduced emulsion and thereby degrades cyclodextrin present in the emulsion and a cholesterol-reduced milk with a residual content of less than 150 ppmw of cyclodextrin is obtained and so milk obtained is subjected to a heat treatment.

Description

The invention relates to a method for reducing the content of sterols and in particular of cholesterol in milk, cream.

Cholesterol is a zoster that occurs in all animal cells. It plays an essential role in the human diet. On the one hand, cholesterol is essential, on the other hand, cholesterol is discussed as a risk factor in coronary heart disease. Of particular importance is the dietary cholesterol intake in individuals with hypercholesterolemia. This group of people should absorb as little cholesterol as possible through their diet. As dietary habits become more and more fat-laden with increasing standard of living, cholesterol reduction is a major contributor to the prevention of disease.

Milk has an average cholesterol content of 10.0-14.4 mg / 100 g. Since milk is not only a staple food but also a starting material for other fatty products such as butter, cream and ice cream, it is desirable to reduce the cholesterol concentration already in the milk.

For the reduction of the cholesterol content in food and especially in milk, a number of methods are known. These are essentially distillative, adsorptive processes, crystallization or extraction with solvents, such as CO ₂ . All these methods are quality-reducing, for example, in terms of the sensor or the flavor of the product. Likewise, the known extraction techniques are less selective, since not only the cholesterol concentration but also other essential nutrient components are reduced.

The addition of cyclodextrins for cholesterol reduction of milk is z. B. off US 6110517 . WO 99/17620 and the abstract too KR 20000003013 A known. The abstract too KR 20030078532 A describes the removal of cholesterol from cream by means of beta-cyclodextrin and the homogenization with defatted milk for cheese production. The abstract too KR 20040054319 A describes the removal of cholesterol from cream by means of beta-cyclodextrin for the production of whipped cream. A possible residual content of beta-cyclodextrin in the low-cholesterol composition is not mentioned.

In US 5565226 or EP0763981 B1 describes the use of immobilized enzymes to degrade cyclodextrin residues in food.

An unlimited daily intake of β-cyclodextrins is not permitted. For β-cyclodextrin, an Acceptable Daily Intake (ADI) of 5 mg / kg (body weight) / day applies. Therefore, in order not to be limited in the amount of milk absorbed per day, it is desirable to provide a method which, after cholesterol reduction, provides a 5-cyclodextrin-reduced milk.

This object is achieved by a method, which is characterized in that
in a complexing step, a mixture is prepared by stirring or homogenizing the milk with cyclodextrin to form an insoluble cyclodextrin / cholesterol complex,
in a separation step, the insoluble cyclodextrin / cholesterol complex is separated from this mixture,
thereby obtaining a cholesterol-reduced emulsion and adding to the cholesterol-reduced emulsion a food grade liquid amylase thereby degrading cyclodextrin present in the emulsion and obtaining a cholesterol-reduced milk having a residual cyclodextrin content of less than 150 ppmw, preferably less than 100 ppmw and more preferably less than 50 ppmw becomes
and the milk thus obtained is subjected to a heat treatment.

The milk is preferably raw whole milk, homogenized whole milk, raw milk, homogenized skimmed milk, raw cream, homogenized cream or a mixture of these components.

The cyclodextrin is preferably alpha, beta or gamma cyclodextrin, more preferably beta cyclodextrin or a beta cyclodextrin containing mixture of said cyclodextrins.

Preferably, 0.5 to 15% by weight of cyclodextrin is added based on the weight of the milk / cream.

The complexation is preferably carried out over a period of 5 to 60 minutes at a temperature of 5 to 60 ° C.

In a preferred variant of the method, in the homogenizing step, first the entire amount of cyclodextrin required skim milk is added and mixed and preferably dissolved, then a desired fat content is set with milk or cream. Alternatively, the total amount of cyclodextrin is added to whole milk and a desired fat content is then adjusted with cream. This method step is also referred to below as prefetching.

Preferably, the mixing of the cyclodextrin with the milk or milk fractions takes place with an agitator, homogenizer or Ultra Turrax. Particularly preferably, the mixing takes place with a stirrer.

The separation of the insoluble cyclodextrin / cholesterol complex in the separation step is preferably carried out by means of a centrifuge, filtration or by settling. The separation or separation of the cholesterol / cyclodextrin complex preferably takes place by means of a centrifuge or settling vessel, more preferably by means of a centrifuge.

Amylase is a food-grade amylase. The direct addition of the liquid amylase to the process allows for better mixing and thus more efficient degradation of the cyclodextrin than the use of immobilized enzymes known in the art. Furthermore, the technical complexity for carrying out in a production operation is low due to the procedure according to the invention.

Preferably, 10 to 460 AU amylase (AU = amylase unit, amount of enzyme which degrades 3000 mg of starch at pH 4.7 and 37 ° C per hour) are added per gram of cyclodextrin. Particularly preferably 40 to 200 and in particular 50 to 150 AU are added.

The amylase is over a period of preferably 10 min. to 6 days at preferably 5 ° C to 65 ° C added to the emulsion. Preferably, the reaction temperature is 20 ° C to 65 ° C at preferably 30-180 min, more preferably at 40 ° C to 65 ° C for more preferably 30 to 120 min. or even more preferably at a lower temperature of 5 ° C to 25 ° C, the reaction time is more preferably 3 to 5 days.

The cholesterol- and cyclodextrin-reduced milk thus obtained is subjected to a heat treatment in order to inactivate the amylase. Preferably, a pasteurization or sterilization process usual for milk takes place.

Preferably, the milk is heated to temperatures of 85 ° C to 150 ° C, more preferably at 120 ° C to 140 ° C for preferably 3 to 30 s, more preferably for 3 to 10 s.

The heat treatment can be carried out for the sake of simplification by the usual heat treatment methods for milk for preservation. Thus, no additional inactivation step for the enzyme is then necessary in the process according to the invention. Particularly preferred for H-milk (UHT to greater than 135 ° C, greater than 10 s) and ESL milk (Extended Shelf Life, 127 ° C for 1-2 s) takes place for sufficient amylase inactivation heat treatment. Any remaining activities that may be present are insignificant for the quality and composition of the drinking milk, since apart from the added cyclodextrin, no further constituents of the milk can be catalyzed by the amylase, and the enzyme must be approved for food.

The process steps cyclodextrin addition and separation in the process according to the invention can be repeated several times, whereby cholesterol reductions in the product of> 95% can be achieved.

• • Beheiz-/kühlbare Rührbehälter, für die Durchführung des erfindungsgemäßen Verfahrens,
• • Filtrationsanlagen, bevorzugt Nano-/Mikrofiltration für den Separationsschritt,
• • Separatoren, bevorzugt Tellerzentrifugen für den Separationsschritt
• • Hochdruckhomogenisatoren für die Durchmischung der Komponenten im Komplexierschritt, oder nach Zusatz der Amylase.

The inventive method is characterized by a simple implementation in the industrial production process of drinking milk / whole milk / cream. It is possible to use machines that are commonly used in dairies:

• Heatable / coolable stirred containers, for carrying out the method according to the invention,
• Filtration systems, preferably nano / microfiltration for the separation step,
• • Separators, preferably disc centrifuges for the separation step
• • High-pressure homogenizers for the mixing of the components in the complexing step, or after addition of the amylase.

The cyclodextrin and cholesterol reduced milk or cream obtained in the process according to the invention are cooled and packaged in the usual way or by conventional methods to any known dairy products such. As cream, butter, cheese, yogurt or ice, which are also reduced cholesterol and beta-cyclodextrin reduced.

For the purposes of the present invention, a cyclodextrin-reduced milk or cream is preferably to be understood as meaning that the cyclodextrin content of the milk or cream is preferably below 200 ppmw and, with milk, particularly preferably below 100 ppmw. The cholesterol content of the low-cholesterol milk or cream is preferably reduced by at least 60%, more preferably by> 85%, in comparison to the milk / cream used.

In the following, the implementation of the method according to the invention will be described in more detail using the example of process variants described in FIG 1 are described, wherein process variant 1 describes the treatment of skim milk and process variant 2, the treatment of cream. Variation 3 describes the treatment of raw or homogenized whole milk. The simplest process variant is the treatment of whole milk according to the invention by the steps of complexing, separation and heat treatment.

In process variants 1, 2 and 3, the skimmed milk, whole milk or the cream are mixed with cyclodextrin, more preferably with beta-cyclodextrin. Beta-cyclodextrin concentrations in skimmed milk, whole milk and cream of 0.5-15% by weight, preferably 1.0-5.0% by weight, more preferably 1.0-3.0% by weight, are used Cream preferably 2.0-15 wt .-%, particularly preferably 3.0-10.0 wt .-%. All wt .-% information in the context of the present invention description / examples always refer to the weight of the total treated milk or the cream (100%).

1 shows three variants of the method according to the invention.

Method 1:

In skim milk, only low concentrations of cholesterol are found, therefore, in method 1, the variant with predissolved cyclodextrin, preferably beta-cyclodextrin, is particularly preferred. For this purpose, 0.5-15 wt .-%, preferably 1.0-5.0 wt .-%, particularly preferably 1.0-3.0 wt .-% based on the total amount of milk used in cyclodextrin in skim milk used. The mixing takes 2 to 30 min at 5 to 60 ° C, more preferably 2 to 10 min., Particularly preferably 10 to 50 ° C in a stirred tank. This pre-solution process can also be performed with an Ultra Turrax or a homogenizer.

After pre-dissolving, the cream fraction is added, which introduces the majority of cholesterol into the solution. This can be standardized to a desired fat content of the milk.

In the next step, the complexation is carried out at 5 to 60 ° C for 5 to 60 min., Particularly preferably for 5 to 20 min., Particularly preferably 10 to 50 ° C, preferably by stirring with a propeller mixer, an Ultra Turrax or a homogenizer. In the case of using non-homogenized skimmed milk and non-homogenized cream, homogenization of this mixture is particularly preferably carried out after mixing skim milk and cream.

When using a stirrer, a homogeneous mixing, depending on the equipment and specification of the agitator with preferably 10 to 1,000 rpm or when using an Ultra Turrax preferably 800 to 1,500 rpm carried out.

As a result of the complexation, the water solubility of the cyclodextrin changes and the complex precipitates. The now insoluble cholesterol / cyclodextrin complex is separated by centrifugation, filtration or sedimentation. The separation or separation of the cholesterol / cyclodextrin complex preferably takes place by means of a centrifuge or sedimentation vessel, more preferably by means of a Centrifuge. It is preferably centrifuged to 20,000 × g. After separation of the water-insoluble complex, a residual concentration of the beta-cyclodextrin used is present in solution.

To reduce the remaining dissolved beta-cyclodextrin 10 to 460 AU amylase are added, preferably 40 to 200 AU and particularly preferably 50 to 110 AU, each per gram added amount of cyclodextrin. The degradation reaction takes place in a temperature range of preferably 5 to 65 ° C for preferably 10 min. to 6 days, preferably for 10 to 180 min. at preferably 20 to 65 ° C, particularly preferably at 40 to 65 ° C for more preferably 20 to 80 min. or even more preferably at a lower temperature of 5 ° C to 25 ° C, more preferably 3 to 5 days.

The inactivation of the amylase is carried out by a heat treatment of the milk. For this purpose, the milk is heated to temperatures of preferably 85 ° C to 150 ° C, more preferably at 120 ° C to 140 ° C for preferably 3 to 30 s, more preferably for 3 to 10 s. The heat treatment can be carried out for the sake of simplification by the usual heat treatment methods for milk for preservation. Thus, no additional inactivation step for the enzyme is then necessary in the process according to the invention. The method for heat treatment for ESL and UHT or H milk is particularly preferably used as a substep of the process according to the invention. This means that milk holding times of at least 127 ° C are used for 1 to 2 s and 135 ° C for 10 s.

Method 2:

In the inventive method 2 in 1 are added to the cream fraction having a total fat content of greater than 20% by weight, preferably 2.0-15% by weight, more preferably 3.0-10.0% by weight, of beta-cyclodextrin.

The complexation takes place for 5-60 min. at preferably 5-60 ° C, particularly preferably for 5-20 min., Particularly preferably 10-50 ° C, preferably by stirring with a propeller mixer, an Ultra Turrax or a homogenizer. After the described complexing can be carried out according to the invention before the separation and degradation step, a standardization with skim milk to a desired fat content or the cholesterol-reduced cream phase for the production of other dairy products such. As the cream, butter, cheese, yogurt, ice cream are used.

The degradation of the residual beta-cyclodextrin and the inactivation of the amylase is carried out as described in Method 1.

Method 3:

In the method 3 according to the invention, it is preferred to add to whole milk 1.0 to 5.0% by weight of beta-cyclodextrin, more preferably 1.0 to 3.0% by weight of beta-cyclodextrin. The complexation is then carried out preferably for 10 to 60 min., At preferably 10 to 60 ° C, particularly preferably for 5 to 20 min. at particularly preferably 10 to 40 ° C, preferably by stirring with a propeller mixer, an Ultra Turrax or a homogenizer. After complexing, the separation is particularly preferably carried out by means of a centrifuge, preferably up to 20,000 × g. The degradation of the residual beta-cyclodextrin and the inactivation of the amylase is carried out as described in Method 1.

The following examples serve to further explain the invention:

example 1

Cholesterol-reduced whole milk after prediluted beta-cyclodextrin in skimmed milk

example 1

Each 100 g skimmed milk were heated to 50 ° C. In each case from 1.0 to 4.0 wt .-% beta-cyclodextrin was added (see Table 1) and these mixtures for 3 min. mixed at 800 rpm with a magnetic stirrer. Afterwards, cream was standardized to a fat content of 3.5%. This was followed by a 10 min. Treatment of the mixture in the Ultra Turrax laboratory mixer at 2,000 rpm as a complexing step.

The separation of the insoluble precipitate consisting essentially of the cholesterol / cyclodextrin complex was carried out by centrifuging with a laboratory centrifuge for 15 min. at 50 ° C and 200 g Acceleration. The resulting supernatant was withdrawn. The cholesterol content of the supernatant was determined by means of chromatographic methods. In the following table, cholesterol reductions are listed as a function of the beta-cyclodextrin concentration used. From a beta-cyclodextrin addition of more than 3.0% by weight, a cholesterol reduction greater than 90% was achieved. Tab. 1 attempt 1.1. 1.2. 1.3. 1.4. 1.5. Addition of beta-cyclodextrin [% by weight] 1.0 1.5 2.0 3.0 4.0 Colesterin reduction [%] 61 70 74 90 92

The cholesterol-reduced milk samples 1.1. to 1.5. (Table 1), were mixed with 35 and 125 AU / g cyclodextrin amylase and at 55 ° C for 90 min. and 120 min. tempered with gentle stirring. This treatment resulted in a reduction of the beta-cyclodextrin in the samples below 50 ppmw.

Example 2

Cholesterol reduction from cream

In each case 50 g of homogenized cream were heated to 50 ° C. In each case 1.0 to 5.0 wt .-% beta-cyclodextrin was added (see Table 2) and these mixtures for 10 min. mixed at 500 rpm with a stirrer.

The separation of the insoluble precipitate, which consists essentially of the cholesterol / cyclodextrin complex, is determined by centrifugation with a laboratory centrifuge for 15 min. separated at 50 ° C and 200 × g acceleration. The cholesterol content of the supernatant was determined by means of chromatographic methods. With increasing dosages of beta-cyclodextrin results in a cholesterol reduction greater than 80%. Tab. 2 attempt 2.1. 2.2. 2.3. 2.4. Addition of beta-cyclodextrin [% by weight] 1.0 1.5 3.0 5.0 Cholesterol reduction [%] 26 56 67 84

The cholesterol-reduced cream samples (Table 2) were mixed with 50 to 150 AU / g cyclodextrin amylase and at 55 ° C for 90 to 120 min. tempered with gentle stirring. By this treatment, a reduction of beta-cyclodextrin below 150 ppmw was achieved.

Example 3

Cholesterol reduction in whole milk by varying the process temperature

Each 100 g of whole milk were heated to 40 ° C. In each case from 1.0 to 3.0 wt .-% beta-cyclodextrin was added (see Table 3) and these mixtures for 10 min. mixed at 800 rpm with a magnetic stirrer. The insoluble precipitate was separated by separation for 10 min. separated at 200 × g in a laboratory centrifuge. The cholesterol content of the supernatant was determined by means of chromatographic methods. Tab. 3 attempt 3.1. 3.2. 3.3. Addition of beta-cyclodextrin [% by weight] 1.0 1.5 3.0 Colesterin reduction [%] 70 88 92

The cholesterol-reduced milk samples (Table 3) were mixed with 35 and 125 AU / g cyclodextrin amylase and at 55 ° C for 90 min. and 120 min. tempered with gentle stirring. By this treatment, a reduction of the beta-cyclodextrin was achieved in the two samples below 50 ppmw.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 6110517 [0005]
• WO 99/17620 [0005]
• KR 20000003013 A [0005]
• KR 20030078532A [0005]
• KR 20040054319 A [0005]
• US 5565226 [0006]
• EP 0763981 B1 [0006]

Claims (8)

Method for cholesterol reduction of milk which characterized in that in a complexing step, a mixture is prepared by stirring or homogenizing milk with cyclodextrin to form an insoluble cyclodextrin / cholesterol complex, in a separation step, the insoluble cyclodextrin / cholesterol complex is separated from this mixture, thereby obtaining a cholesterol-reduced emulsion and adding to the cholesterol-reduced emulsion a food approved liquid amylase thereby degrading cyclodextrin present in the emulsion and obtaining a cholesterol-reduced milk having a residual content of less than 150 ppmw of cyclodextrin and the milk thus obtained is subjected to a heat treatment. A method according to claim 1, characterized in that the milk is raw whole milk, homogenized whole milk, raw milk, homogenized skimmed milk, raw cream, homogenized cream or a mixture of these components. A method according to claim 1 or 2, characterized in that it is the cyclodextrin to beta-cyclodextrin or a beta-cyclodextrin-containing mixture of at least two of said cyclodextrins. A method according to claim 1, 2 or 3, characterized in that 0.5 to 15% by weight of cyclodextrin are added based on the weight of the milk. A method according to any one of claims 1 to 4, characterized in that in the homogenization step, the entire required amount of cyclodextrin skimmed milk is added and mixed with it and then with milk or cream a desired fat content is set or the entire cyclodextrin amount of whole milk is added and a desired fat content then with Cream is set. A method according to any one of claims 1 to 5, characterized in that the mixing of the cyclodextrin with the milk or milk fractions takes place with a stirrer, a homogenizer or an Ultra Turrax. Method according to one of claims 1 to 6, characterized in that the separation of the insoluble cyclodextrin / cholesterol complex in the separation step by means of a centrifuge, filtration or by settling takes place. A method according to any one of claims 1 to 7, characterized in that 10 to 460 AU amylase per gram of cyclodextrin are added.

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