WO2019065651A1

WO2019065651A1 - Yogurt, and method for producing yogurt

Info

Publication number: WO2019065651A1
Application number: PCT/JP2018/035506
Authority: WO
Inventors: 堀内　啓史; 武文市村; 智子市場
Original assignee: 株式会社明治
Priority date: 2017-09-27
Filing date: 2018-09-25
Publication date: 2019-04-04
Also published as: JP2019058132A

Abstract

The method for producing a yogurt according to the present invention comprises a preparation step in which a raw-material milk is prepared, a lactose degradation step in which at least some of the lactose included in the prepared raw-material milk is degraded using a lactase enzyme, an addition step in which lactic acid bacteria are added to the raw-material milk in which at least some of the lactose was degraded, and a fermentation step in which the raw-material milk to which the lactic acid bacteria were added is fermented. In the lactose degradation step, the lactose included in the prepared raw-material milk is degraded until the lactose concentration in the prepared raw-material milk is 1.5% by mass or less. The lactose concentration in fermented milk that results from the fermentation is 1% by mass or less.

Description

Process for producing fermented milk and fermented milk

The present invention relates to fermented milk and a method for producing fermented milk, and more particularly to fermented milk and a method for producing fermented milk capable of suppressing an increase in acidity during refrigeration.

Fermented milk such as yogurt contains viable bacteria of lactic acid bacteria. Therefore, even when fermented milk is stored at low temperature (for example, 10 ° C. or less), fermentation by live bacteria of lactic acid bacteria proceeds, and the acidity of fermented milk increases with time. The increase in acidity causes the taste and taste of fermented milk to be changed immediately after production. It is considered that the flavor and taste of fermented milk immediately after production can be stably maintained by suppressing the increase in acidity of fermented milk during storage.

Patent Document 1 (Japanese Patent Application Laid-Open No. 2016-189709) discloses a method of producing fermented milk capable of suppressing a decrease in pH during storage. In Patent Document 1, lactose degrading enzymes are added to a fermentation mix to degrade lactose contained in fermented milk. Bulgarian bacteria, thermophilus bacteria, bifidobacteria, and gaseri bacteria are added to the fermented mix in which lactose has been degraded. The fermented mix in which lactose has been degraded is fermented by the above four types of lactic acid bacteria. The lactose content of fermented milk after completion of fermentation is 45 mM or less due to lactose decomposition by lactose-decomposing enzyme and lactose decomposition accompanying fermentation by a lactic acid bacteria starter. The fermented milk produced in this manner can slow down the pH drop during storage.
JP, 2016-189709, A

As mentioned above, the manufacturing method of fermented milk which concerns on patent document 1 uses four types of lactic acid bacteria as a starter. Therefore, the method for producing fermented milk disclosed in Patent Document 1 can not be applied to the production of fermented milk containing only Bulgarian bacteria and Thermophilus bacteria. The method for producing fermented milk according to Patent Document 1 has a problem that combinations of usable lactic acid bacteria are limited in producing fermented milk.

An object of the present disclosure is to provide fermented milk and a method of producing fermented milk capable of suppressing an increase in acidity after completion of fermentation regardless of the type of lactic acid bacteria used for fermentation.

The fermented milk according to the present disclosure has a lactose concentration of 1% by mass or less based on the total amount of fermented milk.

Fermented milk according to the present disclosure can suppress an increase in the degree of lactic acid acid at the time of refrigeration regardless of the type of lactic acid bacteria used at the time of production of the fermented milk.

Lactose may not be detected in fermented milk according to the present disclosure. Thereby, the rise of the lactic acid acid degree at the time of refrigeration can be further suppressed.

The fermented milk according to the present disclosure includes Bulgarian bacteria and Thermophilus bacteria and may not contain bifidobacteria. This makes it possible to suppress an increase in the degree of lactic acid acid in fermented milk not containing bifidobacteria.

In fermented milk which concerns on this indication, when fermented milk is preserve | saved at the temperature of 10 degreeC, the rise of lactic acid acidity until 8 days passes from immediately after the completion of fermentation is based on lactic acid acidity of fermented milk immediately after the completion of fermentation. As 0.25, it may be 0.25% or less. The fermented milk which concerns on this indication can suppress the rapid raise of lactic acid acidity in a period of about one week immediately after manufacture.

In fermented milk which concerns on this indication, when fermented milk is preserve | saved at the temperature of 10 degreeC, the rise of lactic acid acidity until 16 days passes immediately after the completion of fermentation is based on lactic acid acidity of fermented milk immediately after the completion of fermentation. As 0.3, it may be 0.3% or less. The fermented milk according to the present disclosure can suppress an increase in lactic acidity in a period of about two weeks.

The method for producing fermented milk according to the present disclosure includes a preparation step, a lactose decomposition step, and a fermentation step. A preparation process prepares raw material milk. In the lactose decomposition step, at least a part of lactose contained in the prepared raw material milk is decomposed using lactose degrading enzyme. A fermentation process adds lactic acid bacteria to the raw material milk in which at least one part lactose was decomposed | disassembled, and ferments the raw material milk to which lactic acid bacteria were added. The lactose concentration in fermented milk after completion of fermentation is 1% by mass or less.

The manufacturing method of fermented milk which concerns on this indication can suppress the raise of the lactic acid acid degree of fermented milk at the time of refrigeration irrespective of the kind of lactic acid bacteria used at the time of manufacture of fermented milk.

In the method of producing fermented milk according to the present disclosure, lactose may not be detected in fermented milk after the end of fermentation. Thereby, the rise of the lactic acid acid degree at the time of refrigeration can be further suppressed.

In the method for producing fermented milk according to the present disclosure, the decomposing step may decompose lactose contained in the prepared raw material milk until the lactose concentration in the prepared raw material milk becomes 1.5 mass% or less. Thereby, the lactose concentration in fermented milk after the completion of fermentation can be made 1 mass% or less.

In the method for producing fermented milk according to the present disclosure, the fermentation process may be performed by adding at least Bulgarian bacteria and Thermophilus bacteria to the decomposed raw material milk. Thus, various types of fermented milk can be produced by combining various lactic acid bacteria in addition to Bulgarian bacteria and Thermophilus bacteria.

In the method of producing fermented milk according to the present disclosure, when the fermented milk after the end of fermentation is stored at a temperature of 10 ° C., the rise in lactic acidity from 8 days after production to the passage of 8 days is It may be 0.25% or less based on the lactic acid degree. Thereby, the rapid rise of the lactic acid acidity of fermented milk in the period of about one week from immediately after manufacture can be suppressed.

The fermented milk and the method for producing fermented milk according to the present disclosure can suppress an increase in acidity after completion of fermentation without limiting the types of lactic acid bacteria that can be used.

FIG. 1 is a table showing temporal changes in the degree of lactic acid acid in fermented milk according to Examples 1 to 3 of the present invention.

Hereafter, the fermented milk which concerns on embodiment of this invention is demonstrated in detail.

[1. Lactose concentration in fermented milk]
The fermented milk according to the present embodiment preferably has lactose at 1% by mass or less with respect to the total amount of fermented milk at the end of the fermentation. By suppressing the lactose concentration in fermented milk to 1% by mass or less at the end of fermentation, regardless of the type of lactic acid bacteria used for producing fermented milk, suppressing the increase in lactic acid acidity of fermented milk at the time of refrigeration Can. In the present embodiment, refrigeration means storage within a temperature range of 0 ° C. or more and 10 ° C. or less. The degree of lactic acid can be obtained by using a conventionally known method of measuring acidity.

More preferably, the fermented milk which concerns on this Embodiment has 0 mass% lactose with respect to whole quantity of fermented milk at the time of completion | finish of fermentation. That is, lactose is not detected from the fermented milk according to the present embodiment. The method of detecting lactose contained in fermented milk is not particularly limited, and conventionally known methods can be used.

The fermented milk which concerns on this Embodiment is fermented milk and a lactic-acid-bacteria drink which were defined by the ministry of milk etc. (December 27, 1951 Ministry of Health ordinance 52nd issue). Fermented milk in the Ministry of Milk, etc. is milk or the like containing non-fat milk solids equal to or more than this fermented with lactic acid bacteria or yeast and made paste-like or liquid, or those frozen. The lactic acid bacteria beverage in the Ministry of Milk, etc. is a beverage obtained by processing milk or the like fermented with lactic acid bacteria or yeast, or using it as a main raw material.

Hereinafter, the fermented milk according to the present embodiment is simply referred to as “fermented milk” unless otherwise described.

Fermented milk contains at least Bulgarian bacteria and Thermophilus bacteria. According to the United Nations Food and Agriculture Organization (FAO) and the World Health Organization (WHO), yogurt is made from milk and lactic acid bacteria, and lactic acid fermentation by both Bulgaria and Thermophilus bacteria causes dairy products such as milk and skimmed milk It is because it is defined as being made. Thus, the fermented milk may not contain any of the gasseri or bifidobacteria. However, the present embodiment does not prevent the use of lactic acid bacteria other than B. subtilis, Bifidobacterium, Bulgaria, and Thermophilus bacteria as a lactic acid bacteria starter.

In the present embodiment, "Bulgarian bacteria" refers to lactic acid bacteria of Lactobacillus delbruechii subsp. Bulgaricus species. "Thermophilus bacteria" refers to lactic acid bacteria of the Streptococcus thermophilus type. Gasseri bacteria are lactic acid bacteria of the Lactobacillus gasseri (Lactobacillus gasseri) type. Bifidobacterium is a lactic acid bacteria of the Bifidobacterium bifidum type.

As described above, when the lactose concentration in fermented milk is 1% by mass or less at the end of fermentation, an increase in the lactic acid acidity of fermented milk at the time of refrigeration is suppressed. Specifically, the fermented milk after fermentation is refrigerated at a temperature of 10 ° C. Under such refrigerated conditions, the rise in the lactic acid content is suppressed to 0.25 mass% or less based on the lactic acid content of the fermented milk after the completion of fermentation in a period from the end of the fermentation to 8 days. That is, in the period from immediately after the production of the fermented milk to the passage of one week, it is possible to suppress the rapid rise of the lactic acidity of the fermented milk.

Under the above-mentioned refrigerated conditions, the increase in lactic acidity is a period of time from the end of fermentation to the passage of 16 days and a period from the end of the fermentation to the passage of 26 days. It is suppressed to 0.3 mass% or less on the basis of lactic acid acidity. That is, in the period from immediately after the production of the fermented milk to the passage of about 2 weeks, it is possible to suppress an increase in the lactic acidity of the fermented milk.

As described above, even if the fermented milk does not contain any of the goose bacteria and the thermophilus bacteria, an increase in the lactic acid content of the fermented milk at the time of refrigeration is suppressed. The fermented milk which concerns on this Embodiment can maintain stably the flavor and taste of fermented milk irrespective of the kind of lactic acid bacteria used for fermentation.

Moreover, when the lactose concentration of fermented milk at the fermentation start time point and the fermentation end time point is 0% by mass, the increase of the lactic acid acidity in the fermented milk is further suppressed. Under the above-mentioned refrigerated conditions, the rise in lactic acid content is suppressed to 0.25% by mass or less based on the lactic acid content of fermented milk in a period from the start of refrigeration until 16 days have passed. Ru. When the lactose concentration of fermented milk at the start of fermentation and at the end of fermentation is 0% by mass, the increase in lactic acid acidity of fermented milk is further suppressed in a period from immediately after the production of fermented milk to about 2 weeks. Can. Fermented milk having a lactose concentration of 0% at the start of fermentation and at the end of fermentation can maintain its flavor and taste more stably.

[2. Lactose concentration in raw milk]
Raw material milk used for producing fermented milk contains a milk component for lactic acid fermentation by lactic acid bacteria containing at least Bulgarian bacteria and Thermophilus bacteria. The raw material milk is prepared by a conventionally known method.

At the start of fermentation, at least a part of lactose contained in raw material milk is degraded by lactase (lactose degrading enzyme). Specifically, the lactose concentration in the raw material milk is preferably 1.5% by mass or less, more preferably 1.0% by mass or less at the start of fermentation. More preferably, the lactose concentration in the raw material milk is 0% by mass at the start of fermentation.

The lactose concentration of the fermented milk at the end of the fermentation is 1% by mass by decomposing the lactose contained in the raw material milk with lactase in advance so that the lactose concentration in the raw material milk is 1.5% by mass or less at the start of fermentation. The following can be adjusted. During fermentation of the raw material milk by the lactic acid bacteria starter, the lactic acid bacteria starter decomposes lactose remaining in the raw material milk.

In addition, by decomposing lactose contained in raw material milk with lactase in advance so that the lactose concentration in raw material milk becomes 1 mass% or less at the start of fermentation, the lactic acid concentration of fermented milk at the end of fermentation is 0 mass% Can be adjusted.

When the lactose concentration in the raw material milk is 5% by mass, in order to set the lactose concentration in the raw material milk to 1.5% by mass or less, the lactose contained in the raw material milk has a lactose decomposition rate of 70% or more. It may be disassembled by When the lactose concentration in the raw material milk is 5% by mass, in order to set the lactose concentration in the raw material milk to 1% by mass or less, lactose contained in the raw material milk is decomposed by lactase so that the lactose decomposition rate becomes 80% or more. do it. Here, the lactose decomposition rate is a ratio of lactose which is degraded by lactase among lactose contained in raw material milk.

The lactose decomposition rate before the start of fermentation is calculated by the following equation.
Lactose decomposition rate = 100 × {(base lactose concentration (% by mass)-desired lactic acid level (%) × 2) / base lactose concentration (% by mass)}

In the above equation, the base lactose concentration is the lactose concentration contained in the raw milk before lactase is added to the raw milk. The desired lactic acid level is a setting value of the lactic acid level of fermented milk immediately after the completion of fermentation, and the unit is%. The desired lactic acid level is set to, for example, 0.7%.

[3. Method of producing fermented milk]
Hereinafter, the method for producing fermented milk according to the present embodiment will be described in detail.

[3.1. Preparation process]
In the preparation process, raw material milk is prepared. As raw materials used for preparation of raw material milk, for example, water, raw milk, skimmed milk powder, whole milk powder, buttermilk, butter, cream, whey protein concentrate (WPC), whey protein isolate (WPI), α-lactalbumin , Β-lactoglobulin and the like.

Raw material milk should just contain the milk component for performing lactic acid fermentation by lactic acid bacteria as mentioned above. For this reason, raw material milk may not contain all the raw materials listed above, and may use raw materials other than the raw materials listed above. The raw material milk can be prepared by a conventionally known method as described above. For example, raw milk can be prepared by producing a mixture by mixing the raw materials listed above and homogenizing the produced mixture. Raw milk prepared in this manner contains lactose. Lactose is contained in raw materials derived from milk such as raw milk, skimmed milk powder, whole milk powder and the like.

[3.2. Lactose decomposition process]
In the lactose decomposition step, at least a part of lactose contained in the prepared raw material milk is decomposed by adding lactase to the prepared raw material milk. Lactase degrades lactose to produce glucose and galactose. The type of lactase added is not particularly limited as long as the optimum pH of the added lactase is in the neutral region or the acidic region. For example, commercially available lactase can be added to raw material milk.

By holding the raw material milk to which lactase is added, for example, in a temperature range of 0 ° C. or more and 50 ° C. or less, degradation of lactose by lactase can be promoted. Preferably, lactose contained in the raw material milk is decomposed with lactase until the lactose concentration in the raw material milk becomes 1.5% by mass or less. When the lactose concentration in the raw material milk prepared in the preparation step is, for example, 5% by mass, the lactose is decomposed until the lactose decomposition rate reaches 70% or more.

More preferably, lactose contained in the raw material milk is decomposed by lactase until the lactose concentration in the raw material milk becomes 1% by mass or less. When the lactose concentration in the raw material milk prepared by the preparation step is, for example, 5% by mass, the lactose is decomposed until the lactose decomposition rate reaches 80% or more. More preferably, lactose contained in the raw material is decomposed with lactase until the lactose concentration in the raw material milk becomes 0% by mass.

Decomposition of lactose by lactase is performed until fermentation of raw milk by Bulgarian bacteria and Thermophilus bacteria is started. The start timing of the fermentation is, for example, the timing when the lactic acid bacteria starter (Bulgarian bacteria and Thermophilus bacteria) is added to the raw material milk.

[3.3. Sterilization process]
In the sterilization step, raw material milk in which lactose has been degraded by lactase is heated and sterilized. A conventionally known method can be used for heat sterilization of the raw material milk. By heat sterilization of raw material milk, lactase added to raw material milk can be inactivated.

The sterilization process may be performed before the lactose decomposition process. In this case, since lactase can continue to decompose lactose in a fermentation step described later, the lactose concentration in fermented milk can be further reduced.

3.4. Fermentation process]
A lactic acid bacteria starter is added to the pasteurized raw material milk, and the raw material milk is fermented under predetermined fermentation conditions. The raw material milk after the fermentation is refrigerated as fermented milk according to the present embodiment.

Fermentation conditions such as fermentation temperature and fermentation time may be appropriately adjusted in consideration of the type of lactic acid bacteria starter added to the raw material milk, the flavor of the desired fermented milk, and the like. For example, by placing the raw material milk in an environment of 30 ° C. or more and 50 ° C. or less, fermentation by lactic acid bacteria can be promoted. The fermentation time is appropriately adjusted according to the fermentation temperature, the type of lactic acid bacteria starter added to the raw material milk, the desired lactic acid level in fermented milk, and the like.

The fermented milk produced by the method for producing fermented milk according to the present embodiment has lactose of 1% by mass or less at the end of fermentation. As a result, regardless of the type of lactic acid bacteria starter used for fermentation, it is possible to suppress an increase in the degree of lactic acid acid when this fermented milk is refrigerated.

In addition, in the said embodiment, the timing of the fermentation start in raw material milk was defined as a timing in which a lactic-acid-bacteria starter is added to raw material milk. However, since the number of lactic acid bacteria starters added to the raw material milk does not increase in the induction phase (period until the logarithmic growth phase starts), lactose is hardly consumed in the induction phase. Therefore, it is possible to define the timing of the initiation of fermentation as the timing at which the logarithmic growth phase of lactic acid bacteria is initiated. In this case, the sterilization step is performed prior to the lactose degradation step. That is, lactase is added to the heat-killed raw material milk. When the start timing of the logarithmic growth phase is the start timing of fermentation, the decomposition of lactose by lactase continues even after adding the lactic acid bacteria starter to the raw material milk. At the start timing of the logarithmic growth phase, the lactose concentration in the raw material milk may be 1.5 mass% or less.

Each embodiment will be described below. However, the present invention is not limited to the following examples.

Example 1
Raw material milk was prepared by mixing 500.0 g of raw milk, 53.2 g of skimmed milk powder, 23.0 g of fresh cream and 403.6 g of tap water. The lactose concentration in the prepared raw material milk was 5% by mass. After the prepared raw material milk was cooled to 5 ° C., 0.2 g of lactase (GODO-YNL, manufactured by Kyoshu Shusei Co., Ltd.) was added to the raw material milk to decompose lactose contained in the raw material milk. Specifically, the decomposition of lactose was continued until the lactose decomposition rate of the raw material milk became 70%. The method of measuring the lactose decomposition rate will be described later. The lactose concentration in the raw material milk in which the decomposition of lactose was completed was 1.5% by mass. Then, the raw material milk from which lactose was decomposed was heat-sterilized at a temperature of 95 ° C., and the heat-sterilized raw material milk was cooled to a temperature of 43 ° C.

Next, lactic acid bacteria isolated from Meiji Probio Yogurt R-1 (Meiji Co., Ltd.) were added to the raw material milk after heat sterilization as a lactic acid bacteria starter. The addition amount of the lactic acid bacteria starter is 20 g. Raw material milk to which a lactic acid bacteria starter was added was filled into a cup container (volume: 100 ml, made of plastic). The raw material milk filled in the cup container was subjected to stationary fermentation in a fermentation chamber at a temperature of 43 ° C. until the lactic acid acidity became 0.7%.

The cupped raw material milk after stationary fermentation was stored as a fermented milk according to Example 1 in a refrigerator at 10 ° C., and the change with time of the lactic acid acidity of the fermented milk according to Example 1 was measured. In addition, the lactose concentration of fermented milk which concerns on Example 1 immediately after the completion of fermentation was 0.25 mass%.

Here, the measuring method of the lactose decomposition rate in raw material milk is demonstrated. First, the lactose content per solid content in raw milk before lactase is added is measured. Next, the glucose content per solid content in the raw material milk is measured from the glucose concentration in the raw material milk in which lactose has been decomposed.

The lactose decomposition rate is calculated by the following equation using the measured lactose content and glucose content.
Lactose decomposition rate (%) = [(glucose content x 2) / lactose content] x 100

The above lactose content can be measured by arginine fluorescence method by high performance liquid chromatography (BUNSEKI KAGAKU, vol. 32, p. E207, published by The Japan Society of Analytical Chemistry, 1983). The above-mentioned glucose content can be measured, for example, using Medisafe Mini (manufactured by Terumo Corporation). Lactose concentration can be calculated from solid content concentration in raw material milk.

Example 2
The process for producing fermented milk according to Example 2 is the same as Example 1 except that lactose contained in raw material milk is degraded by lactase until the lactose decomposition rate becomes 80%. In Example 2, the lactose concentration in raw material milk was 1% by mass before the start of fermentation. The lactose concentration in the fermented milk according to Example 2 was 0% by mass immediately after the completion of the fermentation. That is, immediately after the completion of the fermentation, lactose was not detected from the fermented milk according to Example 2.

[Example 3]
The process of producing fermented milk according to Example 3 is the same as Example 1 except that lactose contained in the raw material milk is degraded by lactase until the lactose decomposition rate becomes 100%. That is, in Example 3, the lactose concentration in raw material milk was 0 mass% before the start of fermentation. The lactose concentration in the fermented milk according to Example 3 was 0 mass% immediately after the completion of the fermentation. That is, lactose was not detected from the fermented milk according to Example 3 both before and after the start of fermentation.

Comparative Example 1
In the process for producing fermented milk according to Comparative Example 1, the lactose decomposition process is omitted from the production method in Example 1. That is, the lactose decomposition rate in the raw material milk according to Comparative Example 1 was 0%, and the lactose concentration in the raw material milk according to Comparative Example 1 was 5% by mass before the start of fermentation. The lactose concentration in the fermented milk according to Comparative Example 1 was 3.75 mass% immediately after the completion of the fermentation.

Comparative Example 2
The process of producing fermented milk according to Comparative Example 2 is the same as Example 1 except that lactose contained in the raw material milk is degraded by lactase until the lactose decomposition rate becomes 50%. In Comparative Example 2, the lactose concentration in the raw material milk was 2.5% by mass before the start of fermentation. The lactose concentration in the fermented milk according to Example 2 was 1.25% by mass immediately after the completion of the fermentation.

[Temperature change of lactic acid degree]
FIG. 1 is a table showing temporal changes in the lactic acid acidity of fermented milk according to Examples 1 to 3 and Comparative Examples 1 and 2. Referring to FIG. 1, in the fermented milks according to Examples 1 to 3 and Comparative Examples 1 and 2, the lactic acid acidity at the end of the fermentation is 0.70%.

The lactic acid acidity of the fermented milk which concerns on the comparative examples 1 and 2 is rising continuously in the period until it passes 28 days after manufacture from the completion | finish time of fermentation. Specifically, the degree of lactic acid in fermented milk according to Comparative Examples 1 and 2 is greater than 1% at 16 days after production. From this, it was confirmed that the flavor and taste of the fermented milk according to Comparative Examples 1 and 2 are greatly changed immediately after production at the time of refrigeration.

On the other hand, the degree of lactic acidity in fermented milk according to Examples 1 to 3 is 1% or less even after 28 days have passed from the end of fermentation when refrigerated. Compared with the lactic acid acidity of the fermented milk which concerns on the comparative example 1, the raise of the lactic acid acidity in fermented milk which concerns on Example 1, 2 is loose | gentle.

Specifically, the degree of lactic acid in fermented milk according to Examples 1 and 2 is 0.93% at 8 days after production, and 0.99% at 16 days and 26 days after production. The degree of lactic acid in fermented milk according to Examples 1 and 2 was constant in a later period after 16 days after production. From the results shown in FIG. 1, by setting the lactose concentration of fermented milk at the end of fermentation to 1% by mass or less, it is possible to suppress an increase in the lactic acid acidity of the fermented milk and the flavor and taste of the fermented milk are stable from the end of fermentation Was confirmed to be maintained.

Moreover, the lactic acid acidity of fermented milk which concerns on Example 3 is 0.92% in 8 days after manufacture, and is rising to 0.93% in 16 days after manufacture. And the lactic acid acidity of the fermented milk which concerns on Example 3 was 0.96% in 26 days after manufacture. That is, the fermented milk according to Example 3 in which the lactose concentration is 0% both before the start of fermentation and after the end of fermentation is higher in lactic acid acidity than in the case of fermented milk according to Examples 1 and 2 according to the increase in lactic acid acid level during refrigeration. It has become apparent that the rise of H. can be suppressed, and temporal changes in taste and taste can be further suppressed.

In the fermented milk according to Examples 1 to 3, the lactic acid acidity on the eighth day after production is 0.95% or less. That is, when the lactose concentration of fermented milk at the end of fermentation is 1% by mass or less, the increase in the degree of lactic acidity from immediately after production until 8 days has elapsed is 0.25% based on the degree of lactic acid at the end of fermentation It became clear that it can be suppressed to the following.

The degree of lactic acid acid on day 26 after production of the fermented milk according to Examples 1 to 3 is 1% or less. That is, when the lactose concentration of fermented milk at the end of fermentation is 1% by mass or less, the increase in the degree of lactic acidity immediately after production until 26 days has passed is 0.3% or less based on the degree of lactic acid at the end of fermentation It became clear that it could be suppressed.

As mentioned above, although embodiment of this invention was described, embodiment mentioned above is only an illustration for implementing this invention. Therefore, the present invention is not limited to the embodiment described above, and the embodiment described above can be appropriately modified and implemented without departing from the scope of the invention.

Claims

Fermented milk having a lactose concentration of 1% by mass or less based on the total amount of fermented milk.
It is fermented milk of Claim 1, Comprising:
Lactose is not detected, fermented milk.
It is fermented milk of Claim 1 or Claim 2, and.
Contains Bulgarian and Thermophilus bacteria,
Fermented milk not containing bifidobacteria.
The fermented milk according to any one of claims 1 to 3, which is
When the fermented milk is stored at a temperature of 10 ° C., the rise in lactic acidity between 8 days after completion of the fermentation is 0.25% or less based on the lactic acidity of the fermented milk immediately after the completion of fermentation Is fermented milk.
It is fermented milk of Claim 4, Comprising:
When the fermented milk is stored at a temperature of 10 ° C., the rise in the degree of lactic acidity from 16 days after the end of the fermentation to 16 days is 0.3% or less based on the lactic acid degree of the fermented milk immediately after the end Is fermented milk.
A preparation step of preparing raw material milk;
The lactic acid bacteria are added to the lactose decomposing step of decomposing at least a part of lactose contained in the prepared raw material milk using lactose degrading enzyme and the raw material milk from which the at least a part of lactose has been decomposed, the lactic acid bacteria are added And a fermenting step of fermenting the raw material milk,
The manufacturing method of fermented milk whose lactose concentration in fermented milk after the completion of fermentation is 1 mass% or less.
It is a manufacturing method of fermented milk according to claim 6,
A method for producing fermented milk, wherein lactose is not detected in fermented milk after completion of the fermentation.
A method for producing fermented milk according to claim 6 or 7,
The said decomposition process is a manufacturing method of fermented milk which decomposes | disassembles lactose contained in the prepared said raw material milk until the lactose concentration in the prepared said raw material milk becomes 1.5 mass% or less.
A method for producing fermented milk according to any one of claims 6 to 8, wherein
The method for producing lactic acid bacteria, wherein the addition step adds at least Bulgarian bacteria and Thermophilus bacteria to the decomposed raw material milk.
The method for producing fermented milk according to any one of claims 6 to 9,
When fermented milk after the completion of the fermentation is stored at a temperature of 10 ° C., the rise in the degree of lactic acidity immediately after production until 8 days passes is 0.25% based on the degree of lactic acidity of the fermented milk after the completion of the fermentation The following is fermented milk.