阅读说明：本技术 低酸味发酵乳的制造方法 (The manufacturing method of low tart flavour acidified milk ) 是由 柏木真理 井上畅子 长冈诚二 于 2018-02-16 设计创作，主要内容包括：本发明的课题是有效抑制发酵后半期中的pH降低。解决手段是一种发酵乳的制造方法,包含：于原料混合物添加乳酸菌发酵剂,从而获得发酵乳基材的工序,及使发酵乳基材于35℃～50℃进行发酵的发酵工序；在发酵工序中,使发酵乳基材的pH从4.6降低至4.4的所需时间为3小时以上。此外,发酵工序中,从于原料混合物添加所述乳酸菌发酵剂至发酵乳基材的pH到达4.6为止的所需时间为9小时以内。(Project of the invention is that effective pH inhibited in fermentation latter half is reduced.Solution is a kind of manufacturing method of acidified milk, includes: lactic acid bacteria fermenting agent is added in raw mixture, thus the process for obtaining acidified milk substrate, and make acidified milk substrate in 35 DEG C~50 DEG C fermentation procedures to ferment；In fermentation procedure, it is reduced to the pH of acidified milk substrate required time 3 hours or more of 4.4 from 4.6.In addition, being within 9 hours from adding required time of the lactic acid bacteria fermenting agent until the pH of acidified milk substrate reaches 4.6 in raw mixture in fermentation procedure.)

1. a kind of manufacturing method of acidified milk, characterized by comprising:

Lactic acid bacteria fermenting agent is added in raw mixture, thus the process for obtaining acidified milk substrate, and

Make the acidified milk substrate in 35 DEG C~50 DEG C fermentation procedures to ferment,

In the fermentation procedure, it is reduced to the pH of the acidified milk substrate required time 3 hours or more of 4.4 from 4.6.

2. the manufacturing method of acidified milk according to claim 1, which is characterized in that

In the fermentation procedure, from the raw mixture adds the lactic acid bacteria fermenting agent to making the acidified milk substrate PH reach 4.6 until required time be 9 hours within.

3. manufacturing method according to claim 2, which is characterized in that

The lactic acid bacteria fermenting agent includes lactobacillus bulgaricus and Thermophilic Bacteria, and the lactobacillus bulgaricus and Thermophilic Bacteria are being wrapped In skimmed milk power culture medium containing 0.1 weight % yeast extract, when carrying out single bacterium culture in 12 hours with 37 DEG C~43 DEG C, institute The lactic acid acidity for stating culture medium becomes 0.8 or more and less than 1.0.

4. manufacturing method according to claim 3, which is characterized in that

Lactobacillus bulgaricus and Thermophilic Bacteria be when being mixed from skimmed milk power culture medium with 37 DEG C~43 DEG C, in PH is reduced in 4.6 bacterial strain combinations below and selects within 9 hours.

5. the manufacturing method according to claim 1, which is characterized in that

The lactic acid bacteria fermenting agent includes lactobacillus delbruockii subspecies bulgaricus OLL205013 plants of (deposit number: NITE BP- And OLS3290 plants of streptococcus thermophilus (deposit number: FERM BP-19638) or OLS3615 plants of (deposit numbers: NITE 02411) BP-01696)。

6. the manufacturing method according to claim 1, which is characterized in that

The lactic acid bacteria fermenting agent includes lactobacillus delbruockii subspecies bulgaricus OLL205013 plants of (deposit number: NITE BP- And streptococcus thermophilus OLS3290 (deposit number: FERM BP-19638) 02411).

Lactobacillus delbruockii subspecies bulgaricus OLL205013 plants a kind of 7. (deposit number: NITE BP-02411).

Technical field

The present invention relates to a kind of manufacturing methods of acidified milk.It specifically describes, the present invention relates in a kind of inhibition fermentation The manufacturing method for the acidified milk that tart flavour is promoted.

Background technique

Acidified milk is Japanese " province of ingredient specification about milk and milk products etc. enables " (hereinafter referred to as " provinces such as cream enable ") In is defined as: so that cream or the cream containing its same above ester-less milk solid etc. is fermented with lactic acid bacteria or yeast, from And paste or liquid person are formed, or the person of being freezed.The example of acidified milk has rigid Yoghourt (solid state fermentation cream), soft Yoghourt (paste acidified milk) and beverage formula Yoghourt (liquid acidified milk).Rigid Yoghourt is mainly by filling containers raw mixture Afterwards, so that it ferment and solidify in container and obtain.Soft Yoghourt is by stirring after making raw mixture be fermented Broken curdled milk, and mixed according to demand with pulp or baste etc., refilling is obtained in container.Beverage Yoghourt is by making raw material After mixture is fermented, liquid is become using homogenizer etc., and mix according to demand with liquid glucose or pulp baste etc., It refills and is obtained in container.

In addition, the provinces such as Japanese cream enable ingredient specification in provide: acidified milk necessarily ester-less milk solid be 8.0% with On, and total lactic acid bacteria number is 1.0 × 10⁷Cfu/g or more.In addition, also being advised in the Yoghourt international standard according to FAO/WHO It is fixed: must to have a large amount of microorganisms (lactobacillus bulgaricus, Thermophilic Bacteria) existence in end product.

In this way, acidified milk contains the raw bacterium of a large amount of lactic acid bacterias etc..Generally become the pH4.6 or less for stablizing and constituting in acidified milk Afterwards, such as in order to which acidified milk is concentrated, and temperature range (such as 30 DEG C~50 DEG C) are promoted to keep under prolonged situation in fermentation, PH, which can be reduced, by lactic acid bacteria lactic acid generated etc. makes tart flavour become strong.In this way, acidified milk is stored in fermentation for a long time Under the situation for promoting temperature range, compared with concentration starts rear a moment, reduces, be difficult to because pH can pass via the time The flavor or quality for keeping acidified milk fixed for a long time.

Thus, for example in order to manufacture the good high concentration Yoghourt of palatability, it is known to which a kind of manufacturing method, being will before fermentation Cream concentration or milk composition powder is added in cream to be fermented (patent document 1) after modulating dense yogurt mixt.This Outside, it is known that there are also a kind of Yoghourt manufacturing method, be by fermentation after Yoghourt be concentrated by UF membrane or centrifuge separation, thus Assign dense sense (patent document 2).As other methods, also considering the side using the lower lactic acid bacteria fermenting agent of sour generative capacity Method.

Summary of the invention

Invent the project to be solved

However, in the revealed method of patent document 1, by be originated from dairy milk starting material mineral composition or milk composition powder from The flavor of body has powder sense, bitter taste, the stronger project of saline taste.In addition, being made in the revealed method of patent document 2 by fermentation Lactic acid bacteria fermenting agent tart flavour in enrichment process can be promoted, and have the feelings for reducing the palatability of the concentration Yoghourt finally obtained Shape.

In addition, having fermentation time longer in the case where using the low lactic acid bacteria fermenting agent of sour generative capacity, being not suitable for work Mass production in industry, and there is pH to be reduced to 4.4 process time shorter from 4.6, if quality can be generated if not cooling down promptly The inconsistent problem of (especially tart flavour) degree.Also that is, in the case where industrial mass production acidified milk, if considering its manufacture effect Rate, then expectation accelerates the fermenting speed of raw mixture (when shortening fermentation in the fermentation first half of pH6.6~pH4.6 or so Between).But it will become if accelerating fermenting speed and generate lactic acid etc. in early period, therefore promote acidified milk to be stored in fermentation for a long time When temperature range (such as 30 DEG C~50 DEG C), the pH in fermentation latter half can be reduced more, have tart flavour degree to become strong problem. For this problem, it has not been able to propose that a kind of fermenting speed by first half of fermenting is maintained at suitable mass production acidified milk so far Speed, and simultaneously can after fermentation half it is interim efficiently inhibit pH reduce technology.

In addition, standing for fermentation cream simultaneously separates light liquid especially in using Greek style Yoghourt as the concentration acidified milk represented (whey) and the enrichment process needs of heavy-fluid (concentration acidified milk) take hours, therefore, if further progress is sent out during it Ferment has the product tart flavour finally obtained and becomes strong project.As the countermeasure of this project, although can be reduced in enrichment process dense Thus the temperature of contracting primary fermentation cream inhibits fermentation, but the separative efficiency of light liquid and heavy-fluid can be made extremely to reduce.In addition, as it It is elongated and not to have fermentation time although also there is the method using the lower lactic acid bacteria fermenting agent of sour generative capacity for his countermeasure The problem of being suitble to the industrial production of concentration acidified milk.Accordingly, it is considered to concentration acidified milk industrial production the case where, it is expected that using Lactobacillus bulgaricus and Thermophilic Bacteria etc. have the lactic acid bacteria fermenting agent of fixed acid generative capacity, and make acidified milk in enrichment process Temperature is maintained at about 40 DEG C.But under these conditions, the acidified milk in enrichment process will do it fermentation, and end product The tart flavour of (concentration acidified milk) still can become strong.Thus, it is difficult to inhibit the tart flavour or fermentative smell of concentration acidified milk.

Therefore, general object of the present invention is to propose that especially the semiduation effectively can inhibit pH to reduce to one kind after fermentation Acidified milk manufacturing method and lactic acid bacteria fermenting agent bacterial strain.In addition, present invention aims at, such as in manufacture concentration fermentation When newborn, even if there is the lactic acid bacteria fermenting agent of fixed acid generative capacity using lactobacillus bulgaricus and Thermophilic Bacteria etc., and dense In the case that maintenance acidified milk temperature is about 40 DEG C in contracting process, the pH being also able to suppress in enrichment process is reduced, to obtain It must inhibit the concentration acidified milk of tart flavour or fermentative smell.

Solve the technical solution of project

First aspect of the present invention is related to the manufacturing method of acidified milk.Manufacturing method of the present invention be comprising, Add lactic acid bacteria fermenting agent in raw mixture, thus the process for obtaining acidified milk substrate, and make the acidified milk substrate in 35 DEG C~50 DEG C fermentation procedures to ferment.Wherein, in fermentation procedure, the pH of acidified milk substrate from 4.6 be reduced to 4.4 institute Take time is 3 hours or more.

As described above, being reduced to pH required time 3 hours of 4.6~4.4 or more, even if for example manufacturing as a result, In the case where acidified milk is concentrated, being also able to suppress pH in enrichment process is reduced, and inhibits tart flavour or fermentative smell to obtain Acidified milk is concentrated.In addition, the present invention can overall application in the manufacturing method of all acidified milks, rather than only be defined in concentration hair The manufacturing method of kefir milk.

In the manufacturing method of acidified milk of the present invention, preferably from raw mixture add lactic acid bacteria fermenting agent to Required time until the pH of acidified milk substrate reaches 4.6 is within 9 hours.Required time until pH reaches 4.6 is more preferable For 8 hours hereinafter, be more preferably 7.5 hours or less again.

As described above, make from lactic acid bacteria fermenting agent be inoculated with complete up to pH reach 4.6 until time become 9 hours with Under, thus, it is possible to avoid the reduction of acidified milk manufacture efficiency.Also that is, the fermentation speed of acidified milk can be maintained in fermentation first half Degree, and half interim effective inhibition pH can reduce after fermentation simultaneously.In particular, because the cooling item of acidified milk can be mitigated Part, so compression or the energy-saving of equipment investment can be sought.Even if being also able to suppress in addition, generating manufacturing issue etc. because of fermentation Quality caused by newborn excessive fermentation reduces.Furthermore it is possible to prevent the reduction of viscosity caused by excessive chilling or lactic acid bacteria number drop Low situation.In addition, in the case where manufacturing the concentration acidified milk of so-called Greek style Yoghourt, system that can be high with thickening efficiency Condition (such as 35 DEG C~50 DEG C of fermentation temperature) is made, to modulate the product for inhibiting tart flavour.

The manufacturing method of acidified milk of the present invention preferably uses the cream comprising lactobacillus bulgaricus and Thermophilic Bacteria Acid bacteria fermentation agent, the lactobacillus bulgaricus and Thermophilic Bacteria have specific mycology property.It specifically describes, bulgarian milk Bacillus and Thermophilic Bacteria are preferably respectively provided with following mycology properties: in the skimmed milk power comprising 0.1 weight % yeast extract In culture medium, when carrying out single bacterium culture in 12 hours with 37 DEG C~43 DEG C, the lactic acid acidity of the culture medium become 0.8 or more and Less than 1.0.In addition, lactobacillus bulgaricus and Thermophilic Bacteria preferably have following mycology properties: under identical measuring condition, making The pH of culture medium becomes 4.1 or more 4.6 or less.In addition, lactic acid bacteria fermenting agent can be only by the lactobacillus bulgaricus and thermophilic Hot bacterium is formed.

As described above, selection meets the bacterial strain of the condition of culture simultaneously by from lactobacillus bulgaricus and Thermophilic Bacteria It is inoculated in raw mixture, is maintained so as to make to be inoculated with the time completed until pH reaches 4.6 from lactic acid bacteria fermenting agent At 9 hours hereinafter, and being reduced to the pH of acidified milk substrate required time 3 hours or more of 4.4 from 4.6.Also that is, if Lactic acid acidity after the single bacterium culture is 0.80 or more, then the required time since fermentation until pH reaches 4.6 can become Must be shorter, and can more improve productivity.In addition, can more have if lactic acid acidity less than 1.0 after the single bacterium culture Effect inhibits the pH in fermentation latter half to reduce (acidity promotion).In addition, in the present invention, if using the bulgarian milk of specific bacterial strain Bacillus and Thermophilic Bacteria are as lactic acid bacteria fermenting agent, then because the pH for being able to suppress acidified milk in fermentation latter half is reduced, It is not required to carry out specially treated in fermentation procedure, productivity can be maintained in mass production acidified milk.

In the manufacturing method of acidified milk of the present invention, lactobacillus bulgaricus that lactic acid bacteria fermenting agent is included and thermophilic Hot bacterium preferably from skimmed milk power culture medium with 37 DEG C~43 DEG C mixed culture when, pH is reduced to 4.6 or less within 9 hours Bacterial strain combination in select.In addition, lactic acid bacteria fermenting agent can also be for only by this lactobacillus bulgaricus and the bacterial strain of Thermophilic Bacteria Combination.

In the manufacturing method of acidified milk of the present invention, lactobacillus bulgaricus is preferably Lactobacillus delbrueckii OLL205013 plants of subspecies (deposit number: NITE BP-02411).In addition, Thermophilic Bacteria is preferably OLS3290 plants of streptococcus thermophilus (deposit number: FERM BP-19638) or OLS3615 plants (deposit number: NITE BP-01696).Particularly preferably Bao Jiali Sub- lactobacillus is OLL205013 plants and Thermophilic Bacteria is OLS3290 plants.Lactic acid bacteria fermenting agent by these specific bacterial strains Bulgaria The combination of lactobacillus and Thermophilic Bacteria is formed.

Shown in embodiment as be described hereinafter, present inventors found that, by using lactobacillus delbruockii subspecies bulgaricus The OLL205013 plants of lactic acid bacteria fermenting agents combined with OLS3290 plants of streptococcus thermophilus (or OLS3615 plants) being capable of more significant performance Effect of the invention.

The second aspect of the present invention is related to the bacterial strain for the lactic acid bacteria (lactobacillus bulgaricus) that lactic acid bacteria fermenting agent is included. Lactic acid bacteria of the invention is lactobacillus delbruockii subspecies bulgaricus OLL205013 plants (deposit number: NITE BP-02411).This Outside, there are following mycology properties described OLL205013 plants.

A) OLL205013 plants in the skimmed milk power culture medium comprising 0.1 weight % yeast extract, with 37 DEG C~43 DEG C When carrying out single bacterium culture in 12 hours, the lactic acid acidity of the culture medium becomes 0.8 or more and less than 1.0.

B) OLL205013 plants in the skimmed milk power culture medium comprising 0.1 weight % yeast extract, with 37 DEG C~43 DEG C When carrying out single bacterium culture in 12 hours, the pH of the culture medium becomes 4.1 or more 4.6 or less.

C) OLL205013 plants in skimmed milk power culture medium, with 37 DEG C~43 DEG C with other Thermophilic Bacterias be mixed when, In PH is reduced to 4.6 or less within 9 hours.

Shown in embodiment as be described hereinafter, present inventors found that, by using OLL205013 plants described, can generally mention Fermenting speed in height fermentation first half, and the pH in fermentation latter half can be inhibited to reduce.Also that is, generating mixing Bulgaria When the leavening of the acidified milk manufacture of lactobacillus and Thermophilic Bacteria, if lactobacillus bulgaricus utilizes OLL205013 plants, certain No matter using which kind of bacterial strain of Thermophilic Bacteria in degree also fermenting speed can be improved in fermentation first half, and can send out simultaneously Inhibit pH to reduce in ferment latter half, through the invention research, the feature becomes more clear.It can be inferred that this hair Bright characteristic effect is centered on OLL205013 plants.

Invention effect

The present invention provide can after fermentation half it is interim it is effective inhibit pH reduce acidified milk manufacturing method and lactic acid bacteria Leavening.

Specific embodiment

Below by way of Detailed description of the invention specific embodiment.The present invention is not limited to modes described below, also include this Technical field is suitably changed with what knowledge personnel carried out in the following manner and in understanding range.

In present specification, " deposit number: FERM ... " refers to the independence of the international depository authority of budapest treaty Independent administrative institution's industrial technology sums up the deposit number in research institute's Patent Organism collection.In addition, " deposit number: NITE ... " Refer to that the independent administrative legal person's products assessment technique basal disc organization patent microorganism of the international depository authority of budapest treaty protects The deposit number at hiding center.

In present specification, unless otherwise indicated, not so " A~B " refers to " A or more B or less ".

In present specification, " raw mixture " is the liquid containing milk composition such as lactogenesis, rich milk, skimmed milk, whey Body, the liquid containing milk composition of the state before referring to leavening addition process.Wherein, if any the animal of cow's milk etc. for lactogenesis Cream.In raw mixture, other than the milk composition of lactogenesis, rich milk, skimmed milk, whey etc., can containing its processed goods (such as Whole milk powder, full-cream concentrated milk, skimmed milk power, skim concentrated milk, condensed milk, whey powder, butter milk, butter, cream, cheese, Whey protein concentrate (WPC), whey protein sepd (WPI), α-lactalbumin (α-La), beta lactoglobulin (β-Lg) Deng).In addition, " acidified milk substrate (Yoghourt matrix) " refers to the state after raw mixture adds lactic acid bacteria fermenting agent.In addition, " acidified milk " be by making acidified milk substrate ferment, thus obtain fermentation procedure after state manufacture result object.

The present invention relates to the manufacturing methods of acidified milk.The example of acidified milk has Yoghourt.Acidified milk can be rigid Yoghourt or soft Formula Yoghourt can also be beverage formula Yoghourt.Furthermore it is possible to use the acidified milk that manufactures through the invention as the material of fro-yo Material.Furthermore it is possible to use the acidified milk that manufactures through the invention as the material of cheese.In the present invention, acidified milk also can be Any one of " acidified milk ", " dairy products sour milk beverage ", " sour milk beverage " defined in the order of the provinces such as cream etc..

The manufacturing method of the acidified milk of the present invention substantially modulating process containing raw mixture, heating sterilization work Sequence, a cooling process, leavening addition process, heating process, fermentation procedure and secondary cooling process.

When manufacturing acidified milk, raw mixture modulating process is carried out first.Raw mixture modulating process is modulation conduct The process of the raw mixture of acidified milk material.Raw mixture is also referred to as yogurt mixt.In the present invention, raw mixture can Use well known.For example, raw mixture can also be only made of lactogenesis (lactogenesis 100%).In addition, raw mixture is in addition to life It, can also be to mix its processed goods (such as whole milk powder, full-cream concentration other than the milk composition of cream, rich milk, skimmed milk, whey etc. Cream, skimmed milk power, skim concentrated milk, condensed milk, whey powder, butter milk, butter, cream, cheese, whey protein concentrate (WPC), whey protein sepd (WPI), α-lactalbumin (α-La), beta lactoglobulin (β-Lg) etc.) modulation person.In addition, Soya-bean milk can also be contained in raw mixture other than milk composition, granulated sugar, carbohydrate, sweetener, fragrance, fruit juice, pulp, tie up him Food, food composition and the food additives of life, minerals, grease, ceramide, collagen, milk Phospholipids, polyphenol etc. Deng.In addition, can be containing pectin, soybean polyoses, CMC (carboxymethyl cellulose), agar, bright according to needed in raw mixture Stabilizer, tackifier, the gelling agent etc. of glue, carragheen, glue class etc..In raw mixture modulating process, preferably by making original The process that homogenizes that material mixture homogenizes, so that fat globule contained by raw mixture etc. be made to carry out micro- vitrification (crushing). By the process that homogenizes, in the manufacturing process of acidified milk or after manufacture, raw mixture, fermentation are able to suppress or prevented Newborn substrate, acidified milk fat constituent separation or float.

Heat-sterilization step is carried out after raw mixture modulating process.Heat-sterilization step is to heat raw mixture The process of sterilization.Such as in heat-sterilization step, heating temperature and heating time can be adapted to raw mixture The degree sterilized of miscellaneous bacteria, and heated.In the present invention, heat-sterilization step is able to use known method. For example, can be infused by heat-exchangers of the plate type, tubing heat exchanger, steam-sprayed heating device, steam in heat-sterilization step Enter formula heating device, energized heating device etc. to be heated, can also be added by the charging basket with heating mantle Heat treatment.Moreover, being that it is short can to carry out high temperature in rigid or soft situation of original flavor formula etc. in Yoghourt in heat-sterilization step The heat treatment of time sterilization processing (HTST) etc.；In the case where Yoghourt is beverage formula etc., it can also carry out at ultra high temperature sterilization Manage the heat treatment of (UHT) etc..In addition, for example in heat-sterilization step, sterilization processing (HTST) can will be former between high temperature, short time Expect that mixture carries out the heat treatment of 3 minutes~15 minutes degree with 80 DEG C~100 DEG C, ultra high temperature sterilization handles (UHT) can be with The heat treatment of 110 DEG C~150 DEG C progress, 1 second~30 seconds degree.

A cooling process is carried out after heat-sterilization step.Cooling process is by the original after heated sterilization processing The process that material mixture is cooled to predetermined temperature etc..In cooling process, raw mixture is cooled to and promotes temperature than fermentation Spend the temperature of range (such as 30 DEG C~50 DEG C) more low temperature.In the present invention, one time cooling process is able to use known method.Example Such as, a cooling process can carry out cooling place by heat-exchangers of the plate type, tubing heat exchanger, vacuum (decompression) devaporizer Reason can also carry out cooling treatment by the charging basket with heating mantle.In addition, in particular, in a cooling process preferably Raw mixture is set to be cooled to 15 DEG C or less.Moreover, preferably making raw mixture be cooled to 1 DEG C in a cooling process ~15 DEG C, 3 DEG C~10 DEG C are more preferably cooled to, and be more preferably cooled to 5 DEG C~8 DEG C.

In addition, preferably will promote temperature in a cooling process in heat-sterilization step and mixed up to 100 DEG C or so of raw material Object rapid cooling is closed to low temperature (15 DEG C or less).Moreover, sterilization process is the feelings of heat treatment for example in a cooling process Under condition, preferably make to be cooled to 15 DEG C of time up to the raw mixture of 100 DEG C of degree in sterilization process promotion temperature Within 10 minutes, within more preferably 5 minutes, and within more preferably 1 minute, within particularly preferably 30 seconds.By described Cooling process is able to suppress protein in raw mixture and is excessively denaturalized or the phenomenon that carbohydrate brown stain.

Leavening is carried out after cooling process or in cooling process adds process.Leavening addition process is mixed in raw material Object adds (mixing) lactic acid bacteria fermenting agent, thus the process for obtaining acidified milk substrate.It also that is, can be in the original after heat-sterilization step After material mixture is reduced to predetermined temperature, lactic acid bacteria fermenting agent is added, can also be dropped in the raw mixture after heat-sterilization step During predetermined temperature, lactic acid bacteria fermenting agent is added.In the present invention, leavening addition process is able to use known side Method.But in the present invention, lactic acid bacteria fermenting agent, which is preferably at least, contains lactobacillus bulgaricus and Thermophilic Bacteria.Also that is, " protecting and adding Leah lactobacillus " is lactobacillus delbruockii subspecies bulgaricus (Lactobacillus delbrueckii Subsp.Bulgaricus), " Thermophilic Bacteria " is streptococcus thermophilus (Streptococcus thermophilus).In addition, this hair In bright, leavening is added in process, other than lactobacillus bulgaricus and Thermophilic Bacteria, can also add lactic acid known to (mixing) Bacterium.For example, leavening addition process in, can add lactobacillus gasseri (L.gasseri), Lactococcus lactis (L.lactis), Lactococcus lactis subsp (L.cremoris), Bifidus (Bifidobacterium) etc..In addition, lactobacillus-fermented Agent is particularly preferably, and is only made of lactobacillus bulgaricus and Thermophilic Bacteria as lactic acid bacteria.On the other hand, lactic acid bacteria fermenting agent Quantity used by the manufacturing method of known acidified milk can be used in additive amount.

In the present invention, lactobacillus bulgaricus and Thermophilic Bacteria contained by lactic acid bacteria fermenting agent are preferably had the following properties (hereinafter referred to as " the first property "): in the skimmed milk power culture medium containing 0.1 weight % yeast extract, with 37 DEG C~43 DEG C When carrying out single bacterium culture in 12 hours, the lactic acid acidity of the culture medium becomes 0.8 or more and less than 1.0 (not including 1.0).More It is preferably 0.8~0.98, and more preferably 0.8~0.95 with the lactic acid acidity of the culture medium of condition." skimmed milk power culture Base " is the culture medium as composed by skimmed milk power and water, especially by skimmed milk power: 10 weight %, water: 90 weight % are formed Person.In addition, " yeast extract " specifically beer yeast extract, relative to 100 weight % of skimmed milk power culture medium, Contained with 0.1 weight % in skimmed milk power culture medium.In addition, " single bacterium culture " is separated in lactobacillus bulgaricus and Thermophilic Bacteria In the state of, the cultural method of lactic acid bacteria of the same race is cultivated in a culture medium.In addition, in present specification, culture medium " acidity " (lactic acid acidity) is that " test method(s) of the ingredient specification of cream etc. " is enabled to measure according to provinces such as creams.In particular, being tried in 10g Not carbonated ion exchange water 10ml is added in sample, and adds the phenolphthalein solution 0.5ml as indicator.Then on one side It adds sodium hydroxide solution (0.1mol/L), is titrated on one side using the range that blush does not disappear as boundary, from the hydrogen-oxygen The titer for changing sodium solution finds out the lactic acid content of the every 100g of sample as acidity (lactic acid acidity).In addition, phenolphthalein 1g is dissolved It refills in ethanol solution (50%) to 100ml, to modulate phenolphthalein solution.

In addition, in the present invention, lactobacillus bulgaricus and Thermophilic Bacteria are preferably from having the following properties (hereinafter referred to as " the Two properties " ") bacterial strain combination in select: when in skimmed milk power culture medium with 37 DEG C~43 DEG C mixed culture, 9 hours with Interior pH is reduced to 4.6 or less." mixed culture " refers in the state of mixing lactobacillus bulgaricus and Thermophilic Bacteria, trains at one Support the cultural method of two kinds of lactic acid bacterias of culture in base.In present specification, " pH " is measured according to following methods.Also that is, making With glass electrode formula pH meter (HM-30R, East Asia DKK system have temperature correction function), glass electrode, In are inserted into sample 100g Numerical value reads measured value when becoming the fixed stage, the pH as sample.

In the present invention, preferably lactobacillus bulgaricus and Thermophilic Bacteria with first property and the second quality are mixed The lactic acid bacteria fermenting agent of conjunction is for manufacturing acidified milk.As a result, shown in embodiment as be described hereinafter, it can make to add from raw mixture It is maintained the time required to (fermentation first half) during until the lactic acid bacteria fermenting agent to the pH of acidified milk substrate arrival 4.6 Within 9 hours, and make simultaneously the pH of acidified milk substrate from 4.6 be reduced to 4.4 until during (fermentation latter half) taken Between become 3 hours or more.

Lactobacillus delbrueckii Bao Jiali can be enumerated as the lactobacillus bulgaricus with first property and the second quality Subspecies OLL205013 (deposit number: NITE BP-02411).In addition, the Thermophilic Bacteria with the first property and the second quality OLS3290 plants of streptococcus thermophilus (deposit number: FERM BP-19638) and OLS3615 plants of (deposit numbers: NITE can be enumerated BP-01696).Therefore, in the present invention, lactic acid bacteria fermenting agent is preferably the OLL205013 using mixing lactobacillus bulgaricus Strain and Thermophilic Bacteria OLS3290 strain or OLS3615 plants.Especially by the OLL205013 for being selected as lactobacillus bulgaricus Strain, and it is selected as the OLS3290 strain of Thermophilic Bacteria, effect of the present invention is played to can dramatically.

In addition, in leavening addition process, the bacterium of lactobacillus bulgaricus and Thermophilic Bacteria contained by lactic acid bacteria fermenting agent Number (aerobic plate count) can be numerical value used by the manufacturing method of known acidified milk.Moreover, for example, the contained guarantor of lactic acid bacteria fermenting agent The bacterium number of Leah lactobacillus and the ratio of the bacterium number of Thermophilic Bacteria is added to be generally 1:4~1:5.In addition, in particular, leavening adds In process, with the bacterium number of Thermophilic Bacteria contained by lactic acid bacteria fermenting agent be 1 (benchmark) when, the ratio of the bacterium number of lactobacillus bulgaricus (bacterium number/Thermophilic Bacteria bacterium number of lactobacillus bulgaricus) can be 0.01~0.8, preferably 0.05~0.7, more preferably 0.1 ~0.5, and more preferably 0.2~0.4.On the other hand, Bulgarian contained by lactic acid bacteria fermenting agent in leavening addition process The bacterium number (aerobic plate count) of lactobacillus and Thermophilic Bacteria can also make in advance containing lactobacillus bulgaricus bacterium number more than Thermophilic Bacteria Bacterium number.For example, ratio of the bacterium number of lactobacillus bulgaricus relative to the bacterium number of the Thermophilic Bacteria contained by lactic acid bacteria fermenting agent It can be 1.0~5.0 or 1.5~4.0 etc..In addition, the bacterium number of lactic acid bacteria can measure according to known methods.

Heating process is carried out after leavening adds process.Heating process is to will be cooled to that lactic acid bacteria fermenting agent can be added Degree (1 DEG C~15 DEG C) acidified milk substrate be warming up to fermentation promote temperature range (for example, 30 DEG C~50 DEG C) process.In This, " fermentation promotes temperature range " refers to activation microorganism (lactic acid bacteria etc.) and carries out or promote the temperature of acidified milk substrate fermentation Degree.In the present invention, heating process is able to use known method.Such as in heating process, heat-exchangers of the plate type, tubular type can be passed through Heat exchanger etc. is heated, and can also be heated by the charging basket with heating mantle.Moreover, for example, lactic acid The fermentation of bacterium promotes temperature range to be generally 30 DEG C~50 DEG C.In addition, in particular, in heating process, preferably by acidified milk Substrate is warming up to 30 DEG C or more.In addition, acidified milk substrate is preferably warming up to 30 DEG C~50 DEG C, more preferably in heating process To be warming up to 33 DEG C~48 DEG C, and more preferably it is warming up to 35 DEG C~46 DEG C.

In addition, in heating process, preferably by the acidified milk substrate of the temperature reduction in a cooling process in pre- timing Between (short period) be warming up to fermentation promote temperature range.For example, temperature in process will be kept to reduce in low temperature in heating process To 10 DEG C of degree acidified milk substrate be warming up to fermentation promote temperature range time be preferably within 1 hour more preferably 30 Within minute, and within more preferably 10 minutes, within particularly preferably 1 minute.In addition, temperature can be made in heating process Reduced acidified milk substrate is directly moved to the fermenting cellar that room temperature is set as 30 DEG C~50 DEG C degree, and in fermenting cellar on one side by The temperature that edges up carries out heating treatment on one side.

Fermentation procedure is carried out after heating process.Fermentation procedure is to make to be warming up to the acidified milk base that fermentation promotes temperature range The process that material ferments while being maintained at the fermentation and promoting temperature range.In particular, the fermentation of acidified milk substrate It is the temperature range progress at 35 DEG C~50 DEG C.Fermentation procedure is able to use known method.For example, fermentation procedure can pass through hair Ferment room etc. carries out fermentation process, can also carry out fermentation process by the charging basket with heating mantle.In addition, in such as fermentation procedure, The indoor temperature that can will ferment (fermentation temperature) maintains 30 DEG C~50 DEG C, and by the temperature of acidified milk substrate in the fermenting cellar Degree maintains 35 DEG C~50 DEG C, to carry out the fermentation process of acidified milk substrate.In addition, can also will have in the charging basket of heating mantle Temperature (fermentation temperature) maintain 30 DEG C~50 DEG C, and the temperature of the acidified milk substrate in the charging basket is maintained 35 DEG C ~50 DEG C, to carry out the fermentation process of acidified milk substrate.Wherein, in fermentation procedure, the condition for making acidified milk substrate ferment can Consider the type or quantity of raw mixture or lactic acid bacteria, the flavor of acidified milk or mouthfeel etc., with appropriate adjustment fermentation temperature or Fermentation time etc..In addition, in particular, acidified milk substrate is preferably maintained at 35 DEG C or more in fermentation procedure.In addition, hair In ferment process, acidified milk substrate is preferably maintained at 35 DEG C~50 DEG C, more preferably 37 DEG C~48 DEG C, particularly preferably 40~ 46℃.In addition, in particular, acidified milk substrate is preferably maintained at the state that fermentation promotes temperature range in fermentation procedure Lower 1 hour or more.Moreover, (fermentation time) is preferably 3 hours~30 small during the holding of acidified milk substrate in fermentation procedure When, more preferably 6 hours~25 hours, and more preferably 10 hours~20 hours.In addition, in the present invention, in fermentation procedure, hair The temperature of kefir milk substrate, which can fix, maintains 35 DEG C~50 DEG C of range, without going up and down temperature.

Fermentation procedure includes fermentation first half and fermentation latter half.Fermentation first half is to add lactic acid from raw mixture During bacterium leavening agent is until the pH of acidified milk substrate reaches 4.6.The time of the fermentation first half is shorter, then is fermentation Newborn production efficiency is higher.In the present invention, under the conditions of the temperature for making the temperature of acidified milk substrate maintain 35 DEG C~50 DEG C, fermentation Within the required time of first half becomes 9 hours.Furthermore it is preferred that be within 8 hours the time required to being fermentation first half, it is more excellent It is selected as within 7 hours.The required time lower limit of fermentation first half is not particularly limited, such as preferably 4 hours or more, 5 hours Above or 6 hours or more.

Fermentation latter half be acidified milk substrate pH from 4.6 be reduced to 4.4 during.The time of fermentation latter half is longer, It is then that the acidified milk is not allowed to be also easy to produce even if fermentation promotion temperature range (such as 30 DEG C~50 DEG C) is kept for a long time yet It is inconsistent in quality (especially acidity).In the present invention, the temperature of acidified milk substrate is being maintained to 35 DEG C~50 DEG C of temperature Under the conditions of degree, the required time for latter half of fermenting becomes 3 hours or more.In addition, the required time of fermentation latter half is preferably 3.5 Hour or more, more preferably 4 hours or more, and more preferably 4.5 hours or more.The required time upper limit of fermentation latter half does not have Especially limitation, such as preferably 10 hours hereinafter, 8 hours hereinafter, or 6 hours or less.

In addition, in accordance with the invention it is possible to the tart flavour of acidified milk substrate is inhibited to be promoted and be can be carried out simultaneously in fermentation procedure Long-term fermentation.Therefore, the present invention is suitble to the concentration acidified milk of manufacture inhibition tart flavour.Therefore, in fermentation procedure, standing hair can be carried out Kefir milk substrate, so that the acidified milk substrate be made to be separated into the enrichment process of light liquid (whey) and heavy-fluid (concentration acidified milk).Point After process, light liquid is removed from acidified milk substrate, thus, it is possible to obtain the concentrated acidified milk of milk composition (concentration acidified milk).This Outside, this so-called " standing ", which refers to, is not stirring or mixing cultured milk substrate, is separated into the light liquid of light weight in its natural state And the degree of the heavy-fluid of quality weight, and external pressure is not applied to acidified milk substrate and stood in advance.It is excellent when carrying out this enrichment process It is selected as making the temperature of the acidified milk substrate in fermentation procedure to promote in 30 DEG C~50 DEG C (preferably 35 DEG C~50 DEG C) of fermentation Temperature range makes fermentation time 9 hours or more (preferably 10 hours or more).In fermentation procedure, although acidified milk can be made The temperature of substrate be cooled to such as 10 DEG C hereinafter, but the separating rate of the light liquid in the case of this and heavy-fluid it is obviously slack-off, therefore not It is preferred that.In addition, in the present invention, enrichment process and nonessential process can also manufacture general hair under without enrichment process Kefir milk (Yoghourt).

Secondary cooling process is carried out after fermentation procedure.Secondary cooling process is cooling and fermentation process acidified milk obtained The process of (especially concentration acidified milk).In secondary cooling process, the temperature by reducing acidified milk inhibits the progress of fermentation. At this point, making acidified milk be cooled to the temperature that more below fermentation promotes temperature range in secondary cooling process.In the present invention, two Secondary cooling process is able to use known method.For example, in secondary cooling process can Tong Guo Leng KURA room, freezing chamber and cooled down Processing, can also carry out cooling treatment by heat-exchangers of the plate type, tubing heat exchanger, the charging basket with heating mantle.In addition, tool It says to body, in secondary cooling process, acidified milk is preferably made to be cooled to 15 DEG C or less.Moreover, in secondary cooling process, preferably So that acidified milk is cooled to 1 DEG C~15 DEG C, is more preferably cooled to 3 DEG C~10 DEG C, and be more preferably cooled to 5 DEG C~8 DEG C.Pass through The secondary cooling process, makes acidified milk be cooled to edible temperature, and thus, it is possible to inhibit or prevent the flavor of acidified milk (tart flavour etc.), mouthfeel (the tip of the tongue sense of touch etc.), physical property (hardness etc.) generate variation.Acidified milk after secondary cooling process can It is stored in cold KURA room etc., and is saved during 3 DEG C~10 DEG C of low temperature is long.