JPH0458846A - Production of milk fat spread - Google Patents

Abstract

PURPOSE:To obtain the subject product having a stable emulsion type in spite of a high water content and useful as a butter substitute without an emulsifier, etc., by adding a specific amount of a milk protein to a cream having a milk fat content in a specified range and subsequently converting the phase of the mixture into a water-in-oil phase with a shear emulsifying machine. CONSTITUTION:A cream having a milk fat content of 25-75wt.% is mixed with 2-10 pts.wt. of milk protein and the mixture is converted into a water-in-oil phase with a shear emulsifier preferably at an average shear rate of 200-7000 to obtain the objective product.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing milk fat spread.
The milk fat spread obtained by the production method of the present invention is a so-called low-fat spread that can be used as a substitute for butter in confectionery/bread making, as a raw material for cooking, or as a spread for toast.

(Prior art) In recent years, as diets have become richer, cholesterol intake and the development of arteriosclerosis caused by it have become a problem.
It has become increasingly important to reduce the intake of foods high in cholesterol and saturated fatty acids.

For this reason, there is a tendency to reduce the fat content of various foods that originally have flavor due to the inclusion of fat.

Butter originally consists of more than 80% milk fat (based on standards) and has a unique flavor not found in other foods, but recently butter has been reduced to 80% milk fat while maintaining the flavor of butter as much as possible. Low-fat milk fat spreads with a concentration of less than 50% have been put on the market, and methods of producing them are being researched.

The manufacturing method for these includes: 1) Adding and mixing other raw materials to dissolved milk fat to prepare a water-in-oil emulsion composition;
A method of cooling and solidifying using a surface scraping heat exchanger, etc.
■A method of manufacturing butter using a butter manufacturing device using ordinary cream separated from milk as a raw material, and dispersing an aqueous solution of milk protein in the butter (British Patent No. 1.604, 36)
No. 3), (2) A method in which an oil-in-water emulsion composition is once prepared and then stirred and cooled using a surface scraping heat exchanger or the like is known.

(Problem to be Solved by the Invention) However, while the above method (■) has the advantage of being able to use a variety of raw materials, it has the problem of not being able to prevent phase inversion to oil-in-water type during the manufacturing process. This requires special emulsification technology and manufacturing conditions.

Furthermore, in the method (2), it is extremely difficult to uniformly disperse milk proteins, which complicates the manufacturing process, increases opportunities for secondary contamination, and poses problems in maintaining quality.

Furthermore, method (■) simply attempts to invert the phase from an oil-in-water type to a water-in-oil type using an ordinary surface scraping heat exchanger.
Although phase inversion of a part of an emulsion composition with a large amount of aqueous phase can be easily carried out, it is extremely difficult to completely invert the phase of the entire composition, stabilize it during the process, and turn it into a product. There is a problem that the product becomes uneven.

Therefore, the present invention aims at producing a texturally stable wood-in-oil milk fat spread by completely inverting the phase of the cream, which is an oil-in-water composition, during the process, without adding any stabilizers or emulsifiers. The objective is to provide a method.

(Means for Solving the Problems) The present invention provides cream with a milk fat percentage of 25 to 75% by weight.
A method for producing a milk fat spread, which comprises adding and mixing 2 to 10 parts by weight of milk protein, and then inverting the phase in a shear emulsifier to form a water-in-oil type, the method comprising: adding and mixing 2 to 10 parts by weight of milk protein; This is a method in which the phase is inverted, preferably at 200 to 7000 S-', more preferably at 350 to 4000 S-'.

The cream, which is the starting material of the present invention, can be obtained by separating raw milk by a conventional method in one or two stages, or can be used as it is, or can be obtained by dissolving milk fat such as tar or butter oil. You can use reducing cream,
Alternatively, a mixture of both can be used.

The milk fat percentage of the cream is adjusted to 25 to 75% by weight. If the milk fat percentage is less than 25% by weight, the proportion of aqueous phase is high, so it is not possible to transform the milk into a wooden mold in oil in a stable state during the manufacturing process, and the resulting milk product cannot be processed. There is a problem in that water syneresis from the fat spread also occurs, impairing product value.

On the other hand, if the milk fat percentage exceeds 75% by weight, it will approximate the fat percentage of butter, so there is no point in making the milk fat spread low in fat.

The cream thus prepared is maintained at about 50 to 60°C, and 2 to 10 parts by weight of milk components such as milk protein (which may contain lactose, ash, etc.) are added and mixed.

As the milk protein, fermented milk proteins such as cottage cheese and quark, sodium caseinate, whey protein, or protein obtained by acid-treating skim milk, etc. can be used, and one or more of these can be selected and added as appropriate. . Fermented milk protein is particularly preferred from the point of view of flavor.

If the amount of milk protein added is less than 2 parts by weight, the water retention property of the milk fat spread as a product will be lost and syneresis will occur, which will easily impair the product value, and if it exceeds 10 parts by weight, it will cause problems during phase inversion in the subsequent process. Phase inversion becomes difficult.

After adding milk protein to the cream and mixing as above,
It is better to homogenize. This is because the oil-in-water type emulsion composition prepared by adding and mixing milk protein to cream is prone to fat separation during the process (especially when butter or butter oil is added and mixed). , the homogeneous pressure is 3 to 50 kg/ci, preferably 5 to 30 kg/crA. This homogeneous pressure is 3k
g/co! If it is less than 5Qkg/co!, fat separation during the process cannot be prevented; If the fat globules become too fine, phase inversion in the next step is extremely difficult (and the desired product cannot be obtained).

The oil-in-water emulsion composition thus prepared was heated at 4 to 18°C.
, preferably below 10°C. Further, if necessary, acidification may be performed at 10° C. or lower for about 4 to 48 hours.

This temperature is related to the temperature of the obtained product and the structure of the product; if it is too low, some syneresis will occur during the manufacturing process, and if it is too high, kneading will be insufficient, resulting in a hard product and reduced spreadability. .

The cooled oil-in-water type emulsified composition is then phase-inverted to water-in-oil type using a shear emulsifier at an average shear rate of preferably 200 to 7000 s-', more preferably 350 to 4000 s-'.

If this average shear rate is lower than the above value, phase inversion of the entire composition is difficult to occur even if the phase inversion occurs in one part, and therefore it is difficult to form a water-in-oil type structure as a product. If the speed exceeds the above value, emulsification occurs between milk fat and milk protein, and the oil-in-water type emulsification is more likely to be strengthened, so phase inversion to water-in-oil type is difficult to occur in this case as well. .

A good example of a shearing emulsifier is a device in which a single rotating shaft is passed through the center of a horizontal cylinder, and several dozen pins are attached to the inner wall of the cylinder and the shaft in a row or in a zigzag pattern. The above shearing rate can be obtained by rotating this shaft at high speed. A suitable example of this is a pin machine for a margarine manufacturing machine.

Further, as a device having a function corresponding to the bin machine, there can also be mentioned a churning device in a continuous butter making machine. However, the present invention is not limited to these devices, and any device that can obtain an average shear rate within the above range can be used.

For example, in the case of a churning device, the rotation speed of these devices is 1.5 to 3 times higher than that of normal butter production. Similarly, good results can be obtained by increasing the rotation speed of the bin machine by about 1.5 to 2 times.

Here, the shear rate is also called the "sliding rate".
This shows the rate at which pickpockets increase over time. The shear rate D (s-') when the oil-in-water composition passes through the shear emulsifier can be determined by the following formula.

Bin machine shear rate: At the tip, at the center, where do is the gap between the pins (tm), d, is the diameter of the inner cylinder wall (n), and d! is the gap between the inner wall of the cylinder and the tip of the pin (w
), d3 is the diameter [+n) at the midpoint between the inner walls of the cylinder, and N is the number of rotations (r, p, m,).

Note that the average shear rate is the sum of the shear rates at the tip and the center and the average.

Shear rate of the churning device: where r is the radius of the churning cylinder, r
, is the radius of the Varatash rotor (CIll), and N is the rotation speed (r, p, a+, ) of the Paratash rotor.

Thus, when the oil-in-water composition prepared as described above is phase-inverted using the above-mentioned device at an average shear rate within the above-mentioned range, the phase inversion is stable, but the temperature of the obtained water-in-oil composition is 14. It is preferable to set it as the range of -25 degreeC. This temperature is the temperature at which the oil-in-water emulsion composition is fed to the shear emulsifier (4
~18°C), but there is also a slight temperature rise inside the shear emulsifier, so it is necessary to take this into consideration.

The water-in-oil composition obtained by phase inversion in this way exhibits a uniform dispersion state of the aqueous phase (water droplets), but in order to further improve the structure, a line mill, colloid mill, visco rotor, etc. The milk fat spread obtained as a product by passing through an atomization device has a uniform and smooth structure and can be stored for a long period of time.Despite its low fat content, it resembles butter in both structure and flavor. As an alternative, it can be used in confectionery/bread making, as an ingredient in cooking, or as a spread on toast.

(Examples) Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. Note that both % and parts are based on weight.

Example 1 5 parts of 100 parts of cream with a fat percentage of 45% separated from raw milk
After heating to 5°C, add 20 parts of pre-dissolved butter and 5 parts of soda casein as milk protein and mix thoroughly, homogenize using a homogenizer at a pressure of 15 kg/d, and heat to 8°C. It was cooled to obtain an oil-in-water emulsion composition.

Next, this emulsion was aged for 5 hours, and then fed to the churning section of a butter making machine with an average shear rate of 565 seconds for phase inversion to obtain a water-in-oil emulsion composition as a product. Char. The temperature of the product immediately after leaving the coating section was 16℃, and the entire composition had undergone a complete phase inversion, and even as it was, there was no inferiority in terms of structure compared to a normal spread, but in order to further increase the dispersion of water droplets, The milk fat spread was then passed through a line mill of a high-speed atomization device.The obtained milk fat spread had a good Mi texture and excellent spreadability, and did not exhibit syneresis even after being stored at 5°C for one week.

The composition of this milk fat spread is 49.1% fat, 41.9% moisture, 5.2% milk protein, and 3.8% others.
%Met.

Next, in order to obtain optimal water retention and phase inversion conditions, an oil-in-water emulsion composition prepared in the same manner as above was prepared by changing the milk protein content and the shear rate of the shear emulsifier, with other conditions being exactly the same. A water-in-oil emulsion composition was obtained. The phase inversion state of each product obtained and the water retention state of buttermilk were evaluated. The results are shown in Table 1 below.

Table 1 Note) In the table, ×: poor (unsuitable as a product), ○: good (usable as a product), ◎: very good (desirable as a product).

Similarly, Table 2 shows the relationship between milk protein content and quality/phase transformation.

Note) In the table, ×: A lot of syneresis, ○: Hardly any, ◎: Not at all, Easy: Can easily undergo phase transformation, Difficult: Cannot undergo phase transformation.

Example 2 5 parts of 100 parts of cream with a fat percentage of 45% separated from raw milk
After heating to 5°C, add 20 parts of previously prepared fermented milk protein (protein solid rate 17%) and mix uniformly, homogenize with a homogenizer at a pressure of 15 kg/cffl,
It was cooled to 0°C to form an oil-in-water composition.

This oil-in-water emulsion composition was then heated at an average shear rate of 800
The mixture was fed to a pin machine type shear emulsifier (S-') for phase inversion to obtain a water-in-oil milk fat spread with low fat content.

Immediately after coming out of the shear emulsifier, the product temperature was 18°C, the entire composition had undergone complete phase inversion, had good spreadability, and did not exhibit syneresis even after being stored at 5°C for one week.

The composition of the obtained milk fat spread was a fat percentage of 37.
5%, water 54.3%, milk protein 4.5% and other 3.7%.

Example 3 Instead of the butter in Example 1, 20 parts of butter oil of the low melting point fraction obtained by fractionation was added, and 20 parts of fermented milk protein prepared in advance (protein solid rate 17%) was added to this to make a homogeneous mixture. After mixing, the pressure is 15kg/cnl using a homogenizer.
The mixture was homogenized and cooled to 10° C. to obtain an oil-in-water composition.

This was fed to the same pin machine type shearing emulsifier as in Example 2, and the phase was inverted under the same conditions to obtain a water-in-oil type, low-fat milk fat spread.

At a product temperature of 18°C, the entire composition underwent complete phase inversion and had good spreadability, and there was no syneresis even after storage at 7°C for one week.

The composition of the obtained milk fat spread was as follows: fat percentage: 46
．． 4%, water 46.6%, milk protein 3.9% and other 3.1%.

(Effects of the Invention) The low-fat milk fat spread obtained by the method of the present invention has a stable emulsified form despite its high moisture content, and has a more uniform dispersion of water droplets than the conventional method. , emulsifying only milk protein without using emulsifiers or stabilizers,
Since its emulsifying ability can be maximized, there is almost no syneresis, and furthermore, it has excellent flavor and spreadability.

Furthermore, the equipment used in the production process can be the same as the equipment normally used for butter and margarine with only slight modifications, and since no special structure is required, the production cost is low.

Claims (2)

[Claims] (1) Milk fat characterized by adding and mixing 2 to 10 parts by weight of milk protein to cream with a milk fat percentage of 25 to 75% by weight, and then inverting the phase with a shear emulsifier to form a water-in-oil type. How to make spreads. (2) The manufacturing method according to claim 1, wherein the average shear rate during phase inversion using a shear emulsifier is 200 to 7000 s^-^1.