JP2007259831A - Method for producing raw cream, and raw cream having 40-46 mass% of milk fat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing raw cream suppressed in cream floating (creaming) even if having 40-46 mass% of milk fat, and to provide the raw cream having 40-46 mass% of milk fat. <P>SOLUTION: This method for producing the raw cream comprises a sterilization process of sterilizing separate cream obtained by separating raw material milk and having 40-46 mass% of milk fat, a homogenizing process (a) of homogenizing the separate cream after the sterilization process, and a homogenizing process (b) of homogenizing the separate cream before the sterilization process. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a fresh cream having a milk fat content of 40 to 46% by mass, and a fresh cream having a milk fat content of 40 to 46% by mass.

Cream refers to those with a milk fat content (hereinafter sometimes referred to as “fat percentage”) of 18% by mass or more according to ingredient specifications, and other additives (vegetable oils and fats, emulsifiers, stability) There are fresh creams to which no additives are added and synthetic creams to which the above additives are added.
When used for cooking, for example, fresh cream has features such as giving thickening to cooking without separating oil and water. Moreover, fresh cream has a favorable flavor by not containing an emulsifier, a stabilizer, etc., and is also suitable for recent natural orientation.
On the other hand, the synthetic cream has improved physical properties by improving the handling difficulty when storing the fresh cream. However, synthetic creams tend to cause oil-water separation when used in cooking, and are not used in cooking. In addition, since the synthetic cream contains an emulsifier, a stabilizer and the like, it has a unique flavor (eg, taste, taste, astringency, etc.) and a pasty feel.
Thus, fresh cream and synthetic cream have different properties.
“Oil-water separation” as used herein means that the moisture in the cream mixes uniformly with the ingredients of the cooking, while the oil in the cream that does not easily mix with the ingredients of the cooking is ejected, for example, in the form of droplets. It means a state that is.

In the production of synthetic creams, the oil phase part made of an oily raw material and the water phase part made of an aqueous raw material are mixed and emulsified, so both the “pre-emulsification” step and the “homogenization” step are essential steps. ing.
Here, the “preliminary emulsification” step is a temporary emulsification for uniformly dispersing the mixture (emulsion) of the oil phase portion and the aqueous phase portion in the system until the “homogenization” step which is a subsequent step. It is a process. In this “preliminary emulsification” step, relatively coarse fat globules are produced by using a propeller-type mixer or homomixer at 60 to 90 ° C., for example (see Patent Document 1).
The “homogenization” step is a step of stabilizing the coarse fat globules produced in the “preliminary emulsification” step so as to have a particle diameter of 10 to 1 μm or less. In this “homogenization” step, a homogenizer or the like is preferably used.
In the method for producing such a synthetic cream, it is usual that the process of “homogenization” is performed once at a homogenization temperature of 60 to 75 ° C. before or after the sterilization process (Patent Documents 1 and 2; Non-Patent Documents). References 1 and 2).

On the other hand, since the fat content in fresh cream originally exists in an emulsified state, the “pre-emulsification” step and the “homogenization” step are considered to be essential steps like a synthetic cream. Not.
However, in the conventional cream, when it is refrigerated and stored, the fat content that exists as an emulsion in the fresh cream (present as fat globules in the fresh cream) is present on the fresh cream surface. There is a problem of cream surfacing (creaming) in which a thick fat layer (cream layer) of white or yellowish white is formed.
Moreover, in a fresh cream, the favorable whipping property is also calculated | required.

Therefore, in the method for producing fresh cream, a “homogenization” step may be conventionally provided for the purpose of suppressing the cream floating (creaming) and improving cream properties such as whipping properties. In that case, the process of “homogenization” is usually performed once at a homogenization temperature of 60 to 75 ° C., as in the case of the synthetic cream manufacturing method. This “homogenization” treatment may be performed before the sterilization step, but it is considered effective to be performed after the sterilization step so as not to be affected by the sterilization treatment.
JP 2004-269744 A JP 2005-130793 A Milk General Dictionary, p. 171, 175, 176, Asakura Shoten, 1992 Edible oils and fats, p. 246, Sachishobo, 2000

However, if the milk fat content in the cream is high, it is difficult to suppress cream levitation (creaming) even with the usual “homogenization” treatment, and it is difficult to produce a cream with good storage stability. Met.
For this, a solution by using an emulsifier, a stabilizer, etc. can be considered. However, a product obtained by adding an emulsifier, a stabilizer, etc. to a fresh cream (synthetic cream), as described above, has characteristics during cooking. Inferior to fresh cream alone in terms of taste and flavor.
Therefore, even if the milk fat content is high, it is desired to produce a fresh cream having good storage stability without impairing the characteristics of the fresh cream.

  This invention was made | formed in view of the said situation, Comprising: Even if milk fat content is 40-46 mass%, the manufacturing method of the fresh cream in which cream surfacing (creaming) was suppressed, and milk fat content It is an object to provide a fresh cream of 40 to 46% by mass.

In order to achieve the above object, the present invention employs the following configuration.
That is, the method for producing fresh cream according to the present invention includes a sterilization step of sterilizing a separated cream having a milk fat content of 40 to 46% by mass obtained by separating raw milk, and homogenizing the separated cream after the sterilization step. And a homogenization step (b) for homogenizing the separated cream before the sterilization step.
Moreover, in the manufacturing method of the said fresh cream, it is preferable that the homogenization temperature in the said homogenization process (b) shall be 60-90 degreeC.
Moreover, in the manufacturing method of the said fresh cream, it is preferable that the homogenization temperature in the said homogenization process (a) shall be 60-90 degreeC.

  The fresh cream having a milk fat content of 40 to 46% by mass according to the present invention has a cream levitation rate of 2.5% by mass or less after standing at 5 ° C. for 18 days and is added to wine heated to 85 ° C. It is characterized in that water separation is not observed by a wine test in which the sample is heated at 85 ° C. for 2 minutes and then left to stand at 23 ° C. for 10 minutes.

  ADVANTAGE OF THE INVENTION According to this invention, even if milk fat content is 40-46 mass%, the manufacturing method of the fresh cream in which cream surfacing (creaming) was suppressed and the fresh cream whose milk fat content is 40-46 mass% are provided. can do.

≪Method for manufacturing fresh cream≫
The method for producing fresh cream according to the present invention includes a sterilization step of sterilizing a separated cream having a milk fat content (fat percentage) of 40 to 46% by mass obtained by separating raw milk, and the separated cream after the sterilization step. It is a manufacturing method which has the homogenization process (a) which homogenizes, and also the homogenization process (b) which homogenizes the said separated cream before the said disinfection process.

<Isolated cream>
In the present invention, fresh cream is produced using a separated cream having a milk fat content of 40 to 46% by mass, which is separated from raw milk such as milk, raw milk and special milk.
When the milk fat content is more than 46% by mass, the cream viscosity tends to increase when the separated cream is homogenized, and this is not preferable in view of the point of producing a fresh cream stably.
On the other hand, when the milk fat content is less than 40% by mass, a stable fresh cream with suppressed cream levitation (creaming) can be obtained by methods other than the present invention.
For the separation of raw milk, a disk type cream separator or the like is usually used.
The disc-type cream separator includes an open type and a closed type, and the closed type is preferably used because foaming of the separated cream does not occur.
The temperature at which the raw milk is separated is preferably preferably 30 to 60 ° C. By setting it as 30 degreeC or more, the isolation | separation efficiency of separation cream and skim milk improves. On the other hand, when the temperature is 60 ° C. or lower, protein denaturation in the raw material milk and transfer of phospholipid to skim milk are suppressed, and the properties as a fresh cream are improved.
In addition, raw material milk can also be separated at a low temperature of 10 ° C. or lower. By making it 10 degrees C or less, it becomes easy to obtain a fresh cream with a good whipping property. Moreover, the workability | operativity at the time of isolate | separating raw material milk improves.
The milk fat content in the separated cream is determined by adjusting the flow rate of the separated cream separated from the raw milk at the cream outlet of the disc-type cream separator by using a cream regulating valve, for example. Can be controlled.
By separating the raw material milk, it is separated into a separation cream containing fat (fat globules) and skim milk.

<Homogenization step (b)>
Next, the separated cream separated from the raw milk is homogenized.
In this invention, it has the homogenization process (a) which homogenizes the said separated cream after a sterilization process, and the homogenization process (b) which homogenizes the said separated cream further before the said sterilization process.
As described above, by homogenizing the separated cream both before and after the sterilization treatment, the cream rising (creaming) is suppressed without causing quality deterioration such as an increase in cream viscosity (cream thickening). An effect is obtained.
In addition, this homogenization process (b) may have a sterilization process immediately after that, and may have another process between this homogenization process (b) and a sterilization process.

As a homogenization method, for example, a method in which the separated cream is heated to a predetermined homogenization temperature with a plate heater or the like and homogenized with a homogenizer such as a homogenizer is used.
For heating the separated cream, a plate heater, a batch heater or the like is used. Especially, it is preferable to use a plate heater from the point of the heating efficiency of isolation | separation cream.
The homogenization temperature is preferably 60 ° C. or more and less than 100 ° C., more preferably 60 to 90 ° C., and further preferably 70 to 90 ° C.
By setting it to be equal to or higher than the lower limit of the range, the homogenization efficiency of the separated cream is improved. Even when fat globules containing solid fat are present in the separated cream at normal temperature, homogenization by a homogenizer such as a homogenizer is facilitated by heating above the lower limit (reference document: milk). Product Manufacturing, p. 176, Korin, 2004). On the other hand, workability and the flavor of the cream finally produced improve by making it less than the upper limit of the said range, especially 90 degrees C or less. Moreover, the inhibitory effect of cream floating (creaming) improves more by making the said homogenization temperature into 70-90 degreeC.
The upper limit value of the homogenization temperature is substantially the sterilization temperature in the sterilization step (described later), but when the homogenization temperature is 100 ° C. or higher, the flavor of the freshly produced cream In this case, there is an increased possibility that the heating odor and the oxidation odor will become strong.

For homogenizing the separated cream, a homogenizer such as a homogenizer is used. Further, a microfluidizer, a colloid mill, or the like may be used. Especially, it is preferable to use a homogenizer from the point of the homogenization efficiency of separation cream, and the capability of processing amount, and it is preferable to use a two-stage homogenizer among these.
In the homogenization of the separated cream, it is preferable to control the homogenization pressure. Among these, in order to narrow the particle size distribution of the fat spheres in the separated cream, it is preferable to perform multi-stage homogenization by changing the homogenization pressure.
For example, when two-stage homogenization is performed, the homogenization pressure is preferably set to a total pressure of 1 to 3 MPa and a secondary pressure of 0.5 to 1 MPa.
Further, the homogenization pressure needs to be changed according to the production conditions such as the type of homogenizer, the processing flow rate of the separated cream, the shape of the homovalve, and the homogenization temperature.

<Sterilization process>
In the sterilization step, the separated cream homogenized in the homogenization step (b) is sterilized.
As the sterilization method, for example, a high temperature short time sterilization method (HTST), an ultra high temperature sterilization method (UHT) or the like is used, and among them, the ultra high temperature sterilization method (UHT) is preferably used from the viewpoint of sterilization efficiency and flavor.
The sterilization temperature and treatment time are preferably about 82 seconds to 85 ° C. for about 10 seconds in the case of the high temperature short time sterilization method (HTST), and about 120 seconds to 130 ° C. for 2 to 15 seconds in the case of the ultra high temperature sterilization method (UHT). preferable.

<Homogenization step (a)>
In the homogenization step (a), the homogenization treatment is performed on the separated cream sterilized in the sterilization step. In the present invention, in combination with the homogenization step (b), the effect of suppressing cream floating (creaming) can be obtained by homogenizing the separated cream both before and after the sterilization treatment.
In addition, this homogenization process (a) may be immediately after a sterilization process, and may have another process between a sterilization process and this homogenization process (a).

As a homogenization method, the sterilized separated cream is adjusted to a predetermined homogenization temperature by a plate cooler or the like in the UHT apparatus, as in the homogenization step (b), and a homogenizer or the like. A homogenizing method using a homogenizer or the like is used.
The homogenization temperature in the homogenization step (a) is preferably 60 ° C. or more and 100 ° C. or less, more preferably 60 to 90 ° C., and further preferably 70 to 80 ° C.
By setting it to be equal to or higher than the lower limit of the range, the homogenization efficiency of the separated cream is improved. Further, even when fat globules containing solid fat are present in the separated cream at normal temperature, homogenization by a homogenizer such as a homogenizer is facilitated by heating above the lower limit. On the other hand, the upper limit value of the homogenization temperature is substantially the sterilization temperature in the sterilization step, but is 100 ° C. or less, particularly 90 ° C. or less, in terms of workability and the flavor of the fresh cream finally produced. It is preferable that

Moreover, the homogenizer etc. similar to the said homogenization process (b) can be used for the homogenization of isolation | separation cream. Especially, it is preferable to use a two-stage homogenizer from the point of the homogenization efficiency of separation cream.
In the homogenization of the separated cream, it is preferable to control the homogenization pressure. Among these, in order to narrow the particle size distribution of the fat spheres in the separated cream, it is preferable to perform multi-stage homogenization by changing the homogenization pressure.
The homogenization pressure needs to be changed depending on the production conditions such as the type of homogenizer, the processing flow rate of the separated cream, the shape of the homovalve, and the homogenization temperature. Among these, from the viewpoint of the effect of suppressing cream floating (creaming), the average particle size of fat spheres in the separated cream after homogenization is preferably 1.9 μm or more and less than 2.1 μm, more preferably 1.9 to 2. Set to 0 μm. Here, the “average particle diameter” means a median diameter (50 volume% diameter). The median diameter (50 volume% diameter) can be measured using, for example, a laser diffraction particle size distribution analyzer (trade name: LA-500, manufactured by Horiba, Ltd.).
For example, when performing two-stage homogenization, the homogenization pressure is preferably 2 to 4 MPa in total pressure and 0.5 to 1 MPa in secondary pressure.

In the present invention, the separated cream homogenized in the homogenization step (a) is cooled until homogenized (preferably immediately after homogenization), preferably 10 ° C. or less, more preferably 5 ° C. or less. . The lower limit is preferably 0 ° C. or higher.
For this cooling, the plate cooler, the tubular cooler or the like is used. Especially, it is preferable to use the said plate cooler from the point of the cooling efficiency of isolation | separation cream.

After the cooling described above, the cooled separated cream is aged. Thereby, the fresh cream based on this invention can be manufactured.
The temperature during aging is preferably 10 ° C. or lower, more preferably 5 ° C. or lower, and the lower limit is preferably 0 ° C. or higher.
Further, the time spent for aging is preferably several hours to several tens of hours, and more preferably 8 to 12 hours. Thereby, crystallization of the fat etc. in fresh cream advances, and it becomes easy to stabilize the quality of fresh cream.
A refrigerator, an aging tank, etc. are used for aging.

  In the present invention, the milk fat content of the cream finally produced is approximately equal to the milk fat content of the separated cream separated from the raw milk, and is 40 to 46% by mass as in the case of the separated cream.

≪Fresh cream≫
The fresh cream having a milk fat content of 40 to 46% by mass of the present invention is added to wine heated to 85 ° C. with a cream floating rate of 2.5% by mass or less after standing at 5 ° C. for 18 days. Then, separation of water was not observed by a wine test in which the sample was heated at 85 ° C. for 2 minutes and then allowed to stand at 23 ° C. for 10 minutes.

(Cream rise rate)
In the present specification and claims, “cream levitation rate” indicates the degree of cream levitation (creaming), in other words, the inhomogeneity of fat (fat globules) present in fresh cream. Is represented by the following mathematical formula (I).

Cream floating ratio (mass%) = mass of fat layer (cream layer) / total mass of fresh cream × 100
(I)

In the formula (I), the “mass of the fat layer (cream layer)” means the mass of a thick white or yellowish white fat layer (cream layer) that floats on the surface of the fresh cream.
The cream floating rate according to the present invention is specifically determined as follows. That is, 1 kg of fresh cream was filled into a 1 L-capacity paper pack, stored in a refrigerator set at 5 ° C. for 18 days, then passed through a sieve with an opening of 0.355 mm, and collected on the sieve. It calculates | requires according to (I) Formula from the mass of a fat layer (cream layer), and the total mass (1 kg) of fresh cream.
In the fresh cream of the present invention, the cream floating rate is 2.5% by mass or less, preferably 1.5% by mass or less. The lower limit is more preferable, but it is substantially 0.2% by mass or more. When the cream levitation rate is 2.5% by mass or less, cream levitation (creaming) is sufficiently suppressed, and the homogeneity of fat (fat globules) present in the fresh cream within the fresh cream. Indicates a high and stable cream.

(Wine test)
The wine test is a method for evaluating cooking characteristics, that is, the degree of oil / water separation when used in cooking. And it can be confirmed by the wine test whether the characteristic at the time of cooking which is one of the characteristics of fresh cream is maintained without being impaired.
In the present specification and claims, “wine test” means that 80 g of white wine (alcohol 17 °, pH 3.8) is heated to 85 ° C., and 80 g of fresh cream is added to the heated white wine. Means an evaluation method for the state of separation (presence / absence of water separation) of the mixture after heating at 85 ° C. for 2 minutes and further allowing the mixture of the heated white wine and fresh cream to stand at 23 ° C. for 10 minutes. To do.
The separation state of the mixture (with or without water separation) is, for example, the above mixture of white wine and fresh cream heated for 2 minutes is transferred to a 300 mL graduated cylinder and further kept in a thermostatic chamber set at 23 ° C. for 10 minutes. Evaluation can be made by visually observing the mixed state of the mixture after standing.
In the fresh cream of the present invention, water separation is not recognized by the wine test. This shows that it is a stable fresh cream in which the emulsified state of fat (fat globules) present in the fresh cream is maintained without being destroyed. Moreover, when used for cooking, it shows that it is suitable for cooking without separating oil and water. Furthermore, it is excellent in acid resistance and heat resistance and shows that it is difficult to cause feathering.

ADVANTAGE OF THE INVENTION According to this invention, even if a milk fat content is 40-46 mass%, the manufacturing method of the fresh cream in which cream surfacing (creaming) was suppressed and a fresh cream with a milk fat content of 40-46 mass% are provided. can do.
Further, according to the present invention, a fresh cream having a milk fat content of 40 to 46% by mass with good cream characteristics such as whipping properties can be obtained without causing an increase in cream viscosity.
In addition, according to the present invention, a fresh cream with a milk fat content of 40 to 46% by mass having excellent culinary properties and good flavor can be obtained without oil-water separation.

  Hereinafter, the present invention will be described more specifically with reference to test examples and examples, but the present invention is not limited thereto.

≪Test example≫
For Test Examples 1 to 3 for the following purposes, each evaluation was performed as shown below.
Test Example 1: Examination of the number of homogenization treatments and respective homogenization temperatures in the homogenization step (b) before the sterilization step and the homogenization step (a) after the sterilization step.
Test Example 2: Examination of cooking characteristics.
Test Example 3: Examination of the upper limit of milk fat content in fresh cream.

<Test Example 1>
(the purpose)
This test is performed in the method for producing fresh cream according to the present invention, the number of homogenization treatments, and each homogenization temperature in the homogenization step (b) before the sterilization step and the homogenization step (a) after the sterilization step. We carried out for the purpose of searching.

(Sample preparation)
In the production of fresh cream, raw milk was used as raw milk. The raw milk was subjected to a separation treatment using a disk-type cream separator (manufactured by Westphalia) at a separation temperature of 53 ° C. to obtain a separation cream having a milk fat content of 45.5% by mass.
Then, the separated cream was heated to the homogenization temperature in the next homogenization step (b) with a plate heater.
Next, in the homogenization step (b) before the sterilization step, the heated separated cream was homogenized at the homogenization temperatures shown in Tables 1 to 4 using a two-stage homogenizer manufactured by Sanmaru Kikai Co., Ltd. Processed. At this time, the homogenization pressure was 2 MPa in total pressure and 1 MPa in secondary pressure.
Next, in the sterilization step, the separated cream was sterilized at 120 ° C. for 15 seconds using a UHT (ultra high temperature sterilization method) apparatus (manufactured by Morinaga Engineering Co., Ltd., continuous plate sterilizer).
Thereafter, the separated cream sterilized in the sterilization step was cooled to the homogenization temperature in the next homogenization step (a) by the plate cooler in the UHT apparatus.
And in the homogenization process (a) after a sterilization process, the homogenization process was performed at the homogenization temperature shown in Tables 1-4 using the Sanmaru machine Co., Ltd. two-stage homogenizer, respectively. The homogenization treatment at this time uses a two-stage homogenization, and the homogenization pressure is such that the average particle size (median diameter (50% by volume)) of fat spheres in the separated cream after the homogenization treatment is 1.9 μm or more. The total pressure was 3 MPa and the secondary pressure was 1 MPa so as to be less than 1 μm.
Thereafter, the separated cream homogenized in the homogenization step (a) was cooled to 5 ° C. using a plate cooler and aged overnight in a refrigerator (5 ° C.) to produce a fresh cream.

(Preparation of evaluation control sample)
The preparation of the evaluation control fresh cream is performed in the same manner as the preparation of the sample except that the homogenization step (b) prior to the sterilization step is omitted in the preparation of the sample to produce the evaluation control fresh cream. did.
The number of homogenization treatments is twice in the case of the preparation of the sample and once in the case of the preparation of the evaluation control sample.

(Evaluation methods)
The cream buoyancy rate was evaluated for each fresh cream produced, and the relationship between the number of homogenization treatments and the respective homogenization temperatures in the homogenization step (b) and the homogenization step (a) was evaluated.

1) Evaluation of cream levitation rate 1 kg of fresh cream was filled in a 1 L capacity paper pack, and left to stand for 18 days in a refrigerator set at 5 ° C. After storage, a hard yellowish white cream layer that floated on the surface of the fresh cream filled in the paper pack was collected through a sieve having an opening of 0.355 mm, and its mass was measured.
And the cream floating rate (mass%) was calculated | required with the following numerical formula. The results are shown in Tables 1-4. Table 1 shows the results when the homogenization temperature in the homogenization step (a) is 60 ° C. Table 2 shows the homogenization temperature of 70 ° C, Table 3 shows the homogenization temperature of 80 ° C, Table 4 shows the results when the homogenization temperature was 90 ° C.

Formula: Cream floating rate (mass%) = mass of recovered cream layer / total mass of fresh cream (1 kg) × 100

Moreover, in Table 1, the average (mass%) of the cream flotation rate of the number of times of homogenization treatment is the sample No. It is an average value of the cream floating rate (mass%) of 1-2. In addition, the average (mass%) of the cream levitation rate of the number of homogenization treatments twice is the sample No. It is an average value of cream floating rate (mass%) of 3-6.
Moreover, in Tables 2-4, the average (mass%) of cream floating rate is the average value of the cream floating rate of a corresponding sample similarly to the case of the said Table 1, respectively.

  In addition, in this evaluation, the fresh cream manufactured when it has a homogenization process (a) only after the sterilization process tried conventionally is used as an evaluation control.

[When the homogenization temperature in the homogenization step (a) is 60 ° C.]
(result)
From the results in Table 1, sample No. 2 in which the number of homogenization treatments is two is shown. The cream levitation rate of the fresh creams 3 to 6 is the evaluation control sample No. 1 in which the number of homogenization treatments is one. It was confirmed that it tends to be lower than the fresh cream of 1-2.
(Discussion)
Therefore, it was confirmed that the effect of suppressing the cream floating (creaming) in the fresh cream was high by performing the homogenization treatment twice before and after the sterilization step.

[When the homogenization temperature in the homogenization step (a) is 70 ° C.]
(result)
In the results of Table 2, using t-test, which is a statistical processing technique, the number of homogenization treatments is one (1) fresh cream (evaluation control sample No. 11-12) and two (2) fresh cream (sample No. .13-16) were examined for the difference in cream flotation rate. As a result, a significant difference (*) was confirmed between the average values of the cream levitation rates of the two at a level of a risk rate of 5%.
(Discussion)
Therefore, the cream buoyancy rate of the fresh cream (sample Nos. 13 to 16) with two homogenization treatments is lower than that of the single fresh cream (sample Nos. 11 to 12), and the homogenization treatment. It was confirmed that the effect of suppressing the cream floating (creaming) in the fresh cream was high by performing the treatment twice before and after the sterilization step.

[When the homogenization temperature in the homogenization step (a) is 80 ° C.]
(result)
In the results of Table 3, using t-test, which is a statistical processing technique, the number of homogenization treatments is one (1) fresh cream (evaluation control sample Nos. 21 to 23) and two (2) fresh creams (sample No. .24-27) was examined for the difference in cream flotation rate. As a result, a significant difference (*) was confirmed between the average values of the cream levitation rates of the two at a level of a risk rate of 5%.
(Discussion)
Therefore, the cream buoyancy rate of the cream (sample Nos. 24 to 27) with two homogenization treatments is lower than that of the one cream (samples Nos. 21 to 23), and the homogenization treatment. It was confirmed that the effect of suppressing the cream floating (creaming) in the fresh cream was high by performing the treatment twice before and after the sterilization step.

[When the homogenization temperature in the homogenization step (a) is 90 ° C]
(result)
From the results shown in Table 4, sample No. The cream levitation rate of the fresh creams 32 to 35 was evaluated as Sample No. It was confirmed that it tends to be lower than 31 fresh creams.
(Discussion)
Therefore, it was confirmed that the effect of suppressing the cream floating (creaming) in the fresh cream was high by performing the homogenization treatment twice before and after the sterilization step.

  In addition, the sample fresh cream produced when the homogenization temperature in the homogenization step (a) after the sterilization step is 70 to 80 ° C. is higher than the cream of the sample to be evaluated (creaming). It was confirmed that the effect of suppressing is higher.

<Test Example 2>
(the purpose)
This test was conducted for the purpose of confirming that the cream according to the present invention is suitable for cooking.

(Sample preparation)
In the preparation of the sample of Test Example 1, the homogenization temperature in the homogenization step (b) before the sterilization step is set to 60 ° C. for all samples, and the homogenization temperature in the homogenization step (a) after the sterilization step is set to 60 ° C. A fresh cream was produced in the same manner as in Test Example 1 except that each sample was set to 70 ° C. The milk fat content of the separated cream is 45.5% by mass.

In addition, as <reference example>, the cooking property about a synthetic cream was examined similarly.
For the preparation of the synthetic cream, in the preparation of the sample of Test Example 1, instead of the separated cream separated from the raw milk, the composition shown in Table 5 below was used, and the homogenization in the homogenization step (b) before the sterilization step was performed. A synthetic cream was manufactured in the same manner as in Test Example 1 except that the homogenization temperature was 60 ° C. and the homogenization temperature in the homogenization step (a) after the sterilization step was 70 ° C.
The milk fat content of the synthetic cream having the composition shown in Table 5 is 45.5% by mass. Moreover, in preparation of the composition of Table 5, in order to mix and emulsify a water phase part (dissolved water, fresh cream, skim milk powder, an emulsifier) and an oil phase part (butter), it is 60 degreeC by homomixer 7000rpm. And pre-emulsified for 5 minutes.

(Evaluation methods)
The following wine test was performed on the fresh cream and the synthetic cream produced by preparing the above samples, and the culinary properties were evaluated.

2) Wine test 80g of commercially available white wine (alcohol degree 17 degree, pH 3.8) was heated to 85 degreeC. Thereto, 80 g of fresh cream or synthetic cream was added and then heated at 85 ° C. for 2 minutes.
Thereafter, the heated white wine and fresh cream or a mixture of the heated white wine and synthetic cream was transferred to a 300 mL graduated cylinder and allowed to stand in a thermostatic chamber at 23 ° C. for 10 minutes. And the separation state (presence / absence of separation of water) of the mixture after standing was visually observed. The results are shown in Table 6.
In Table 6, (-) indicates "no water separation is observed" and (+) indicates "water separation is permitted", respectively.

(result)
From the results in Table 6, it was confirmed that no separation of water was observed in the mixture containing the fresh cream of the present invention.
In the mixture containing the synthetic cream, water separation was observed.
(Discussion)
Therefore, the fresh cream of the present invention has no oil-water separation, maintains its characteristics during cooking, and is confirmed to be suitable for cooking.

<Test Example 3>
(the purpose)
This test was conducted for the purpose of searching for the upper limit of the milk fat content (fat percentage) in the fresh cream in the method for producing fresh cream according to the present invention.

(Sample preparation)
By using the same raw milk as in Test Example 1, the same separation treatment was performed to obtain separation creams having a milk fat content of 45 mass%, 46 mass%, and 47 mass%.
And the homogenization process performed in a homogenization process was given with respect to the said isolation | separation cream, and each fresh cream was manufactured. The homogenization treatment was performed using a two-stage homogenizer manufactured by Sanmaru Kikai Co., Ltd. at a homogenization temperature of 80 ° C. and a homogenization pressure of 2 MPa.

(Evaluation methods)
The cream viscosity was measured for the fresh cream produced by the above sample preparation, and the relationship with the milk fat content was evaluated.

3) Measurement of cream viscosity The cream viscosity of fresh cream was measured using a cone-plate viscometer Roto Visco1 (trade name, manufactured by Haake) at a cream temperature of 5 ° C and a shear rate of 300 / s. The results are shown in Table 7.

(result)
From the results of Table 7, the difference in cream viscosity between the fresh cream having a milk fat content of 45% by mass and the fresh cream having a milk fat content of 46% by mass is 21 mPa · s, and the cream viscosity is less than 100 mPa · s. It was confirmed that there was.
On the other hand, the difference in cream viscosity between the fresh cream having a milk fat content of 46% by mass and the fresh cream having a milk fat content of 47% by mass is 37 mPa · s, and the milk fat content is 45% by mass and the milk fat content is 46% by mass. It was confirmed that the cream viscosity of fresh cream having a milk fat content of 47% by mass exceeded 100 mPa · s.
(Discussion)
In fresh cream, as the milk fat content increases, the increase in cream viscosity (thickening) by homogenization tends to increase.
From the results of Test Example 3, in the homogenization treatment according to the present invention, it was determined that if the milk fat content was 46% by mass or less, a fresh cream could be stably produced by the method of the present invention.

<Example>
Table 8 shows the milk fat content of fresh cream, the homogenization temperature in the homogenization step (b) before the sterilization step, and the homogenization temperature in the homogenization step (a) after the sterilization step. Each of the fresh creams of Examples 1 to 4 was produced by the same method as the preparation of Sample 1.
For the fresh creams of Examples 1 to 4, the same evaluation of the cream levitation rate and the wine test were performed. In addition, the following whipping property (artificial property) was also evaluated.

4) Evaluation of whipping properties (artificial flowers) Whipped fresh creams are placed in a triangular bag to make flowers, and the shape of the fresh cream (top cut, rough edges) formed at that time is visually observed for whipping. Sex (artificial property) was evaluated.
The evaluation standard is that when fresh cream is artificially flowered, the fresh cream with good whipping property (artificial property) has a shape in which the top is not cut and the edge has a smooth curve.
On the other hand, fresh cream with poor whipping property (artificial property) has a top portion cut and a jagged edge.

As a result of evaluating the cream floating rate with respect to the fresh creams of Examples 1 to 4 according to the present invention, it was confirmed that cream floating (creaming) was suppressed.
In addition, as a result of the wine test, it was confirmed that water separation was not recognized in any of the fresh creams.
Furthermore, as a result of evaluating the whipping property (artificial property), it was confirmed that none of the fresh creams had a shape with a smooth curved edge, and the whipping property (artificial property) was good. It was.

Claims (4)

  A sterilization step of sterilizing a separated cream having a milk fat content of 40 to 46% by mass obtained by separating raw milk, a homogenization step (a) for homogenizing the separated cream after the sterilization step, and further the sterilization A method for producing a fresh cream, comprising a homogenization step (b) of homogenizing the separated cream before the step.   The method for producing fresh cream according to claim 1, wherein the homogenization temperature in the homogenization step (b) is 60 to 90 ° C.   The method for producing fresh cream according to claim 1 or 2, wherein the homogenization temperature in the homogenization step (a) is 60 to 90 ° C. After adding to a wine heated to 85 ° C. with a cream levitation rate of 2.5% by mass or less after standing at 5 ° C. for 18 days, heat at 85 ° C. for 2 minutes, and then leave at 23 ° C. for 10 minutes. A fresh cream having a milk fat content of 40 to 46% by mass, characterized in that no water separation is observed by the wine test.