JP2017225400A - Milk beverage in sealed container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a milk beverage in a sealed container having suppressed proliferation of spore-forming bacteria and good flavor for overcoming problems that food and beverage filled in a can, a bin, a retort pouch or the like is manufactured normally through a heating sterilization for long storage, however a part of spore-forming bacteria is not killed by the heating sterilization and causes deterioration of the food and beverage through spore and proliferation depending on storage conditions.SOLUTION: The above described problem is solved by adding sucrose aliphatic acid ester obtained by a manufacturing method, including a process for radiating a microwave to a mixture containing sucrose and aliphatic acid ester and/or aliphatic acid, to contain a milk solid content of 1.2 wt.% or more.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a milk beverage in a sealed container in which the growth of spore-forming heat-resistant bacteria is suppressed and the flavor is excellent.

  Foods and drinks filled in cans, bottles, retort pouches, etc. are usually manufactured through heat sterilization for long-term storage. However, bacteria that partially form spores are not killed by heat sterilization treatment, and depending on storage conditions, food and drink may be degraded through germination and proliferation. In order to avoid quality deterioration due to such highly heat-resistant bacteria, it is a common practice to add antibacterial emulsifiers such as sucrose fatty acid esters to suppress the growth of spore-forming heat-resistant bacteria.

  Sucrose fatty acid esters are synthesized using sucrose and fatty acids or fatty acid esters as raw materials, but the reaction is very difficult to proceed because of poor reaction efficiency. Therefore, in order to proceed with the reaction, methods such as a reaction at a high temperature using many organic solvents and soaps have been proposed. (For example, refer to Patent Document 1 or 2.)

  However, since these inventions are reacted at a high temperature for a long time, coloring and generation of by-products are observed, and the appearance and flavor of the purified sucrose fatty acid ester are not preferable. Therefore, when mix | blending with food-drinks, there exists a problem of impairing the flavor of food-drinks. In particular, when added to a milk beverage in a sealed container, a unique flavor is imparted, and the original taste and flavor of the milk beverage have been impaired.

JP 59-76098 A JP-A 61-189289

  An object of the present invention is to provide a milk beverage in a sealed container in which the growth of spore-forming thermotolerant bacteria is suppressed and the flavor is favorable.

  As a result of investigations to solve the above-mentioned problems, the present inventors have obtained by a production method comprising a step of irradiating a mixture containing sucrose and a fatty acid ester and / or a fatty acid as a spore-forming heat-resistant bacterial inhibitor. The sucrose fatty acid ester thus obtained was added, and it was found that the flavor was good in a sealed container-containing dairy drink containing 1.2% by weight or more of milk solids, thereby completing the present invention.

That is, the present invention relates to the following.
(1) A milk beverage in a sealed container containing (A) and (B) below.
(A) Sucrose and sucrose fatty acid ester obtained by the manufacturing method including the process of irradiating microwave to the mixture containing fatty acid ester and / or fatty acid 0.01-0.3 wt%
(B) Milk solid content is 1.2 wt% or more. (2) The milk beverage in a sealed container according to (1), wherein the milk fat content is 0.5 wt%.
(3) The milk beverage in a sealed container according to (1) or (2), wherein 70 mol% or more of the constituent fatty acids of the sucrose fatty acid ester is palmitic acid.
(4) The milk beverage in a sealed container according to any one of (1) to (3), wherein the milk beverage is any of milk coffee, milk tea, and cocoa.

  ADVANTAGE OF THE INVENTION According to this invention, the milk beverage in a sealed container with a favorable flavor can be provided.

FIG. 1 is a diagram showing a configuration of a chemical reaction apparatus. FIG. 2 is a diagram showing an example of the internal configuration of the reactor.

Details of the present invention will be described below.
The milk beverage in a sealed container of the present invention contains milk components such as cow's milk, skim milk powder, whole milk powder, concentrated milk, fresh cream, condensed milk, butter, a plastic bottle made of a polyester resin, a plastic cup, It is a type of milk beverage that is filled and sealed in containers such as metal cans, paper packs, and bottles made of metal plates such as tin, aluminum, and tin-free steel.

  In one aspect of the method for producing sucrose fatty acid ester obtained by the production method including the step of irradiating the mixture containing sucrose and fatty acid ester and / or fatty acid with microwaves in the present invention, a mixture containing sucrose and fatty acid ester In addition, an embodiment including a step of irradiating microwaves can be given. By irradiating with microwaves, the transesterification reaction is promoted, and a sucrose fatty acid ester can be obtained in a short time.

  Moreover, the aspect which includes the process of irradiating a microwave to the mixture containing sucrose and a fatty acid as another aspect is mentioned. By irradiating with microwaves, the esterification reaction is promoted, and a sucrose fatty acid ester can be obtained in a short time.

  Sucrose is not particularly limited, but because it has few impurities such as glucose and fructose and is relatively stable during the reaction, it is granulated sugar, white dichotose sugar, medium dichotose sugar, ice sugar, Lactose is preferred. Sucrose may be used alone or in combination of two or more.

  Examples of the fatty acid include saturated or unsaturated fatty acids having 8 to 22 carbon atoms. From the viewpoint of increasing the antibacterial action of the resulting sucrose fatty acid ester, carbon numbers of 16 (palmitic acid) or 18 (stearic acid) are preferable. . The ratio of palmitic acid to fatty acid is preferably 70 mol% or more from the viewpoint of antibacterial action.

  Examples of the fatty acid ester include lower (carbon number 1 to 4) alkyl esters of saturated or unsaturated fatty acids having 8 to 22 carbon atoms and vinyl esters. From the viewpoint of increasing the antibacterial action of the obtained sucrose fatty acid esters. A methyl ester having 16 carbon atoms (palmitic acid) or 18 (stearic acid) is preferred. The ratio of palmitic acid to fatty acid is preferably 70 mol% or more from the viewpoint of antibacterial action.

  A mixture containing sucrose and a fatty acid ester or a mixture containing sucrose and a fatty acid (hereinafter also simply referred to as “mixture”) may optionally contain an additive. The amount of each raw material used in the transesterification reaction or esterification reaction (use ratio) is not particularly limited, and is the same as the amount used in the conventional reaction system.

Examples of additives include emulsifiers, fatty acid soaps, and alkali catalysts.
Microwaves are irradiated to heat the mixture and promote the reaction.
Although the frequency of a microwave is not specifically limited, The frequency etc. in the range of 300 MHz-300 GHz can be used, for example, 2.45 GHz, 5.8 GHz, 24 GHz, 915 MHz etc. are mentioned.

  One frequency of microwaves may be irradiated, and two or more frequencies of microwaves may be irradiated. In the latter case, for example, microwaves of two or more frequencies may be irradiated at the same time, or may be irradiated at different times.

  When microwaves having two or more frequencies are irradiated at different times, for example, microwaves having a frequency that is easily absorbed by the raw material are irradiated at the start of the reaction, and the product is generated when the reaction proceeds. A microwave having a frequency that is easily absorbed by the light may be irradiated.

  Further, for example, microwaves having two or more frequencies may be irradiated at the same position or may be irradiated at different positions. When microwaves of two or more frequencies are respectively irradiated at different positions, for example, they are easily absorbed by the raw material at a position upstream of the flow reactor, that is, at a position where the ratio of the raw material is higher than that of the product. A microwave having a frequency may be irradiated, and a microwave having a frequency that is easily absorbed by the product may be irradiated at a position downstream of the reactor, that is, at a position where the ratio of the product is higher than that of the raw material.

  The method of irradiating the microwave is not particularly limited. For example, a waveguide capable of transmitting microwaves is placed in contact with the reactor, and the mixture is microscopically passed through the waveguide and the reactor. You may make it irradiate a wave.

  In any embodiment, the heating of the mixture may be performed only by microwaves or may be arbitrarily combined with heating means other than microwaves. Further, these may be performed in a batch type (batch type) reactor, or may be performed in a flow type reactor.

  The temperature at the time of synthesis is not particularly limited, but is preferably 60 to 250 ° C, more preferably 80 to 150 ° C. The reaction time is not particularly limited, but is preferably 1 to 20 hours. In carrying out the synthesis, the synthesis environment may be normal pressure or reduced pressure. The fatty acid composition of the sucrose fatty acid ester thus obtained preferably has a palmitic acid ratio of 70 mol% or more from the viewpoint of antibacterial action, and the monoester content in the sucrose fatty acid ester is preferably 70 mol% or more. The monoester content can be increased by purification with a solvent or the like. Although it does not specifically limit as a solvent which can be used, For example, ethyl acetate, isopropanol, propylene glycol, isobutanol, methyl ethyl ketone, etc. are mentioned.

  One aspect of the method for producing a sucrose fatty acid ester of the present invention includes an aspect further including a step of stirring the mixture in advance and / or during synthesis. The method of stirring is not particularly limited, and examples thereof include physical stirring by equipment such as paddle stirring and stirring by a homomixer. Further, a high pressure homogenizer may be used. By stirring the mixture, the reaction efficiency of the mixture is improved. An emulsion may be generated by the mixing.

  One aspect of the method for producing a sucrose fatty acid ester of the present invention includes an aspect further including a step of irradiating the mixture with ultrasonic waves. Ultrasonic waves are irradiated to improve the mixing state of the mixture. An emulsion may be generated by the mixing.

  The frequency of the ultrasonic wave is not particularly limited, but a frequency within a range of 15 kHz to 10 GHz can be used, and examples thereof include 20 kHz, 25 kHz, and 40 kHz.

  Ultrasonic waves may be emitted from a single ultrasonic source, or ultrasonic waves of the same or different frequencies may be emitted from two or more ultrasonic sources. Ultrasound is irradiated continuously, intermittently, or temporarily during the reaction of the mixture, regardless of the presence or absence of microwave irradiation, and ultrasonic waves with different frequencies depending on the time are irradiated from one ultrasonic source. Also good.

  The method of irradiating the ultrasonic wave is not particularly limited. For example, an ultrasonic vibrator may be disposed inside the reactor and the mixture may be directly irradiated with the ultrasonic wave from the ultrasonic vibrator. Alternatively, an ultrasonic transducer may be placed in contact with the reactor, and the mixture may be irradiated with ultrasonic waves through the reactor.

  The microwave and the ultrasonic wave may be irradiated at the same time, or may be irradiated at different times. In the latter case, in order to obtain the effect of microwave irradiation and the effect of ultrasonic irradiation at the same time, for example, the microwave irradiation and the ultrasonic irradiation are switched alternately in a short period of time. It may be.

  FIG. 1 is a diagram showing an example of the configuration of a chemical reaction apparatus 1 used for the above reaction. The chemical reaction apparatus 1 includes a mixing unit 12, a reactor 13, a microwave generator 14, a waveguide 15, a microwave control unit 16, an ultrasonic vibrator 17, an ultrasonic oscillator 18, and an ultrasonic wave. The control part 19 and the process liquid storage tank 20 are provided.

  In the mixing unit 12, the first liquid (sucrose-containing solution) and the second liquid (fatty acid ester-containing solution or fatty acid-containing solution) are premixed before being charged into the reactor 13. For example, the mixing unit 12 may mix the first and second liquids by rotating a blade-shaped member, a wing-shaped member, or a screw-shaped member. Further, the catalyst may be mixed in the mixing unit 12 together with the first and second liquids. The catalyst may be a solid catalyst (heterogeneous catalyst) or a liquid catalyst (homogeneous catalyst). The solid catalyst may, for example, have microwave absorption or microwave sensitivity or not. When the solid catalyst has microwave absorptivity or microwave sensitivity, the solid catalyst is heated by the microwave when the microwave is irradiated inside the reactor 13 described later, and in the vicinity of the solid catalyst. The chemical reaction will be promoted. For example, when 2.45 GHz microwaves are irradiated, carbons other than fullerene (eg, graphite, carbon nanotubes, activated carbon, etc.), iron, nickel, cobalt, Or there is ferrite. In addition, the preheating may or may not be performed in the mixing unit 12. The first and second liquids mixed in the mixing unit 12 are input to the upstream side of the reactor 13.

  The reactor 13 is a horizontal flow type reactor in which the contents flow in the horizontal direction with an unfilled space above. The contents are a mixture of the first and second liquids. In addition, since the product (sucrose fatty acid ester) is produced | generated from the substance contained in the 1st and 2nd liquid by the chemical reaction in the reactor 13, when the product is contained in the contents of the reactor 13 You may think. That is, the contents can be said to be the first and second liquids and / or products. The contents are usually liquid. The inner wall of the reactor 13 is preferably made of a material that reflects microwaves. An example of a substance that reflects microwaves is metal. The internal configuration of the reactor 13 will be described later.

  The microwave generator 14 generates a microwave. The chemical reaction apparatus 1 may include one microwave generator 14 or may include two or more microwave generators 14. The frequency of the microwave is not particularly limited, and may be, for example, 2.45 GHz, 5.8 GHz, 24 GHz, 913 MHz, or the like, and may be other frequencies in the range of 300 MHz to 300 GHz.

  The waveguide 15 transmits the microwave generated by the microwave generator 14 to the unfilled space of the reactor 13. As shown in FIG. 1, there are usually as many waveguides 15 as the number of microwave generators 14. In addition, it is preferable to use the waveguide 15 having a standard corresponding to the frequency of the microwave generated by the microwave generator 14.

  The microwave control unit 16 controls the output of the microwave irradiated to the reactor 13 according to the temperature measured by the temperature measurement unit 25 described later. By the control by the microwave control unit 16, the inside of the reactor 13 can be maintained at a desired temperature or a desired temperature range.

  The ultrasonic transducer 17 generates ultrasonic waves. The ultrasonic transducer 17 is disposed inside the reactor 13 and is connected to the ultrasonic oscillator 18 via a flange or the like. Note that it is preferable that microwaves do not leak in the connection. The ultrasonic vibrator 17 applies ultrasonic vibrations to the contents of the reactor 13 according to the high frequency output received from the ultrasonic oscillator 18. It is preferable that the first and second liquids are mixed with each other according to the ultrasonic vibration. For example, the first and second liquid emulsions may be generated by the ultrasonic vibration. The ultrasonic oscillator 18 generates a high frequency output and supplies it to the ultrasonic transducer 17. The ultrasonic oscillator 18 is controlled by the ultrasonic control unit 19.

  The ultrasonic control unit 19 controls the high frequency output of the ultrasonic oscillator 18. The control may be, for example, control of output (power) magnitude or on / off control. For example, the ultrasonic control unit 19 uses ultrasonic waves so that the magnitude of the high-frequency output according to the first and second liquids and the on / off pattern of the high-frequency output according to the first and second liquids are obtained. The oscillator 18 may be controlled.

  When the contents of the reactor 13 include a catalyst, a catalyst separation unit (not shown) for separating the catalyst from the product after the reaction in the reactor 13 between the reactor 13 and the treatment liquid storage tank 20. ) May or may not be present. In the catalyst separation unit, for example, the solid catalyst may be separated by a filter or precipitation. When the solid catalyst contains a magnetic material, the solid catalyst may be separated by adsorbing the solid catalyst with a magnet. The separated solid catalyst can be reused as appropriate. When a liquid catalyst is used, the catalyst may be separated by distillation, extraction, or neutralization in the catalyst separation unit.

  A product discharged from the reactor 13 is placed in the processing liquid storage tank 20. And it will be divided into final products and by-products as appropriate. That is, a product that is a sucrose fatty acid ester and a by-product such as alcohol and water are obtained, and both are separated in the treatment liquid storage tank 20.

  It should be noted that a cooler (not shown) for cooling the substance after the reaction in the reactor 13 may be provided after the reactor 13 or not. In the former case, for example, the cooler may cool the substance after the reaction in the reactor 13 with water.

  FIG. 2 is a diagram illustrating an example of the internal structure of the reactor 13 according to the present embodiment. In FIG. 2, the reactor 13 has a plurality of chambers 31, 32, and 33 that are continuous in series. Each of the chambers 31 to 33 is partitioned by a plurality of partition plates 21 that partition the inside of the reactor 13. As described above, the unfilled space 22 exists above the reactor 13. The unfilled space 22 is irradiated with the microwave generated by the microwave generator 14 through the waveguide 15. The partition plate 21 may be microwave transmissive, microwave absorptive, or may reflect microwaves. Examples of the material that transmits microwaves include Teflon (registered trademark), quartz glass, ceramic, and silicon nitride alumina. Moreover, the partition plate 21 may be comprised by the combination of arbitrary 2 or more materials among a microwave transparent material, a microwave absorptive material, and a microwave reflective material.

  The contents 30 that are the first and second liquids that have entered the reactor 13 flow between the chambers 31 to 33 and are finally output from the downstream (the right end of the reactor 13 in FIG. 2). The partition plate 21 has a flow path through which the contents flow. The flow path is a flow path in which the contents mainly flow from the upstream side (left side in FIG. 2) to the downstream side (right side in FIG. 2) of the reactor 13, but the short arrows shown in FIG. Thus, a part may flow from the downstream side to the upstream side. The flow path of the partition plate 21 may be, for example, a flow path in which the content overflows above the partition plate 21, or may be a flow path in which the content flows in a gap between the partition plates 21. As such a partition plate 21, for example, various partition plates 21 described in International Publication No. 2013/001629 may be used. The reactor 13 may or may not have a slope that decreases from the upstream side toward the downstream side.

  It should be noted that a stirring means for stirring the contents 30 may or may not exist inside the reactor 13. If stirring means are present, the stirring means may or may not be present for each chamber 31-33.

  In addition, as shown in FIG. 2, the reactor 13 may also include a temperature measurement unit 25. The temperature inside the reactor 13 is preferably the temperature of the content 30 of the reactor 13. Although FIG. 2 shows a case where the temperature measuring unit 25 is present in each of the chambers 31 to 33, this need not be the case. For example, the temperature measurement unit 25 may measure temperature using a thermocouple, measure temperature using an infrared sensor, measure temperature using an optical fiber, or measure temperature using other methods. Good. The temperature measured by the temperature measuring unit 25 is passed to the microwave control unit 16 and used for controlling the microwave output by the microwave generator 14. As described above, the control is for maintaining the temperature of each of the chambers 31 to 33 at a desired temperature or a desired temperature range.

  Further, the ultrasonic oscillator 18 outputs a high frequency output to the ultrasonic transducer 17 according to the control by the ultrasonic control unit 19, and the ultrasonic transducer 17 generates an ultrasonic wave according to the high frequency output. As a result, in each of the chambers 31 to 33, the contents 30 are irradiated with ultrasonic waves, and the first and second liquids are mixed. In addition, the emulsion of the 1st and 2nd liquid may be produced | generated or maintained by the irradiation. By performing such mixing, the contact area between the first and second liquids is increased, and as a result, the reaction between the first and second substances is promoted. This is believed to be particularly noticeable when an emulsion is produced or maintained. Therefore, compared with the case where the first and second liquids are simply stirred with a stirring blade or the like and reacted, when the reaction time is the same, the yield is higher than when no ultrasonic wave is irradiated. When the yield is the same, the reaction time is shorter than when no ultrasonic wave is irradiated.

  The shape of the reactor 13 does not matter. For example, the reactor 13 may have a cylindrical shape in which the horizontal direction in FIG. 2 is the length direction, may have a rectangular parallelepiped shape, or may have another shape. The wall surface of the reactor 13 may be covered with a heat insulating material. By doing so, it is possible to prevent the heat inside the reactor 13 from being released to the outside.

  Next, the operation of the chemical reaction apparatus 1 will be briefly described. The first and second liquids are supplied to the mixing unit 12 by the pump 11. And it mixes in the mixing part 12, and is thrown into the reactor 13. FIG. The supply speed of the raw material or the like to the reactor 13 may be determined in advance.

  The raw material supplied to the reactor 13 flows from the upstream side to the downstream side. At that time, the microwave generated by the microwave generator 14 is transmitted to the unfilled space 22 of the reactor 13 through the waveguide 15 and irradiated to the contents 30. As a result, the content 30 is heated, and the reaction is promoted. In addition, the temperature of each chamber 31-33 is measured by the temperature measurement part 25, and is passed to the microwave control part 16 by the path | route which is not shown in figure. And the microwave control part 16 controls the output of the microwave generator 14 so that the temperature of each chamber 31-33 may become desired temperature or a desired temperature range. Further, the ultrasonic wave generated by the ultrasonic transducer 17 is irradiated to the contents 30. As a result, the first and second liquids are mixed, and the reaction of the substances contained in the first and second liquids is promoted. In addition, the emulsion of the 1st and 2nd liquid may be produced | generated or maintained by irradiation of a microwave and an ultrasonic wave.

  The product output from the reactor 13 is charged into the processing liquid storage tank 20, and is divided into a target product and a by-product in the processing liquid storage tank 20. In this way, the final product, sucrose fatty acid ester, is obtained. By repeatedly executing such processing, sucrose fatty acid esters are sequentially generated.

  Moreover, although the case where the ultrasonic transducer | vibrator 17 exists in each chamber 31-33 of the reactor 13 was demonstrated, it may not be so. For example, in the case of the first and second liquids in which the emulsion is maintained for a long time even after the irradiation of ultrasonic waves is finished, the ultrasonic vibrator 17 is disposed only in the chamber 31, and the emulsion is stored in the chamber 31. You may make it produce | generate. Moreover, although the reactor 13 which has the three chambers 31-33 continued in series was demonstrated, the number of these chambers is not ask | required. The number of chambers may be one, two, or four or more.

  Moreover, although the chemical reaction apparatus 1 provided with the temperature measurement part 25 and the microwave control part 16 was demonstrated, the chemical reaction apparatus 1 does not need to be provided with the temperature measurement part 25 and the microwave control part 16. FIG. For example, when the temperature of the reactor 13 can be maintained at a desired temperature or temperature range by setting the microwave output to a predetermined value, the microwave output control using the temperature is performed. It is not necessary to perform.

  Moreover, although the case where the 1st and 2nd liquid was mixed and thrown into the reactor 13 was demonstrated, it may not be so. For example, the first and second liquids may be charged into the reactor 13 without being premixed. In such a case, the chemical reaction device 1 may not include the mixing unit 12. Moreover, although the case where the chemical reaction apparatus 1 was provided with the process liquid storage tank 20 was demonstrated, it may not be so. For example, with respect to a mixture of products and by-products output from the chemical reaction device 1, the product may be extracted in another device.

  In the above description, the case where the reaction is performed in the horizontal flow type reactor 13 having the unfilled space 22 inside is described. However, the reaction is performed in the flow type reactor 13 having no unfilled space inside. May be. In that case, microwaves are directly irradiated to the contents 30. The flow reactor 13 having no unfilled space inside may be, for example, a vertical reactor. In the vertical reactor, the contents circulate from below to above or from above to below.

In the above description, the case where the ultrasonic transducer 17 is disposed inside the reactor 13 has been described. However, the ultrasonic transducer 17 is disposed outside the reactor 13, and the reactor 13 itself is disposed by the ultrasonic transducer 17. The contents 30 may be irradiated with ultrasonic waves by vibrating the. In the above description, the case where the reaction is performed in the flow type reactor 13 has been described. However, the reaction may be performed in a batch type reactor.
Moreover, you may make it make the 1st and 2nd substance contained in both liquids react by irradiating a microwave and an ultrasonic wave with respect to the 1st and 2nd liquid, without performing premixing.

  In the above description, at least one of the first and second liquids to be irradiated with the microwave and the ultrasonic wave is a liquid that is heated when heated. There may be. Specifically, the first solid solidified from the first liquid and the second liquid are mixed, and the first solid contained in the mixture is irradiated with microwaves or ultrasonic waves by preliminary heating. May be melted into the first liquid. Even in that case, as a result, the first and second liquids are irradiated with microwaves and ultrasonic waves, and the reaction of the first and second substances contained in both liquids can be promoted. it can.

  According to the method for producing a sucrose fatty acid ester according to the embodiment of the flow type reactor, when substances contained in the first and second liquids are reacted, both liquid emulsions are produced and reacted. The area of the liquid interface is increased, and as a result, the reaction is accelerated. Even if the emulsion is not generated by irradiating the first and second liquids with microwaves and ultrasonic waves, both are mixed by the irradiation, and the area of the interface between the two liquids increases. The reaction will be promoted. As a result, a higher yield and a shorter reaction time can be realized, heat-degrading components that cause off-flavors are reduced, and the flavor of the resulting sucrose fatty acid ester is preferable. It is estimated that

  In the milk beverage in a sealed container according to the present invention, the content of the sucrose fatty acid ester obtained by the production method including the step of irradiating the mixture containing sucrose and the fatty acid ester and / or fatty acid with microwave is preferably 0.01. It is -0.3weight%, More preferably, it is 0.02% -0.1%. When the content is less than 0.01% by weight, a sufficient bacteriostatic effect may not be exhibited, and 0.3% by weight or more may not be preferable in terms of production cost.

  Examples of the milk component in the present invention include raw milk, fresh cream, butter, sweetened condensed milk, defatted condensed condensed milk, concentrated milk, defatted concentrated milk, defatted powdered milk, whole fat powdered milk, cheese, milk and other foods. The milk product is not particularly limited as long as it is a dairy product made from milk. These may be used alone or in combination of two or more.

  The content of the milk component in the milk beverage in the sealed container of the present invention is desirably 1.2% by weight or more as the milk solid content in terms of milk flavor, and the milk fat content in terms of exhibiting a good fat feeling. More preferably, it is 0.5% by weight or more. As used herein, the term “milk solid content” refers to a dried product obtained by drying milk components using a general drying method (freeze drying, evaporation to dryness, etc.) to remove moisture.

  The milk beverage of the present invention is coffee, tea or cocoa in which the above milk components are blended. In the present invention, the other components that can be contained in these beverages are usually components that can be contained in these beverages. For example, flavors, coloring agents, emulsifiers, stabilizers, sweeteners, acidulants, spices, antioxidants. An agent, an anti-browning agent, etc. can be contained.

The sterilization treatment of the milk beverage in the sealed container according to the present invention is not particularly limited by sterilization conditions, sterilization apparatuses, or the like, but for example, retort sterilization or UHT sterilization can be employed.
The conditions for retort sterilization and UHT sterilization are not particularly limited as long as they are the conditions used in ordinary sealed dairy beverages, but generally in the range of 120 ° C. to 145 ° C. for 15 seconds to 60 seconds. Done within minutes.
The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to the examples.

Preparation of Sucrose Fatty Acid Esters Synthesis Examples 1-2 Microwave Heating and Ultrasound Irradiation As Synthesis Example 1, 34 g of sucrose, 2 g of sucrose palmitate as an emulsifier, and 50 g of water as an emulsifier were added for 30 minutes at 60 ° C. The solution was completely dissolved by stirring with heating. Further, 27 g of methyl palmitate was heated and melted at 60 ° C. and charged into a three-necked flask. The three-necked flask was placed in a microwave reactor equipped with a stirrer and a thermometer (thermocouple), and then an ultrasonic horn was introduced from the top of the three-necked flask. Then, microwaves (2.45 GHz) and ultrasonic waves (20 kHz) were simultaneously irradiated while stirring, and a transesterification reaction was performed for 5 hours while maintaining the temperature at 90 ° C. ± 2 ° C. The liquid during the transesterification reaction was an oil-in-water emulsion. After completion of the reaction, the mixture was purified using water, methyl ethyl ketone, and ethyl acetate to obtain sucrose palmitate ester A. The ratio of palmitic acid in the constituent fatty acid of this sucrose palmitic acid ester was 80 mol%. It used for the evaluation in the following test examples.

  As Synthesis Example 2, sucrose palmitate ester B was obtained in the same manner except that the palmitic acid ratio was 50 mol% in the synthesis step.

Synthesis Examples 3-4 Microwave Heating As Synthesis Example 3, 34 g of sucrose, 2 g of sucrose palmitate as an emulsifier, and 50 g of water were added to a three-necked flask and completely dissolved by heating and stirring at 60 ° C. for 30 minutes. I let you. Further, 27 g of methyl palmitate was heated and melted at 60 ° C. and charged into a three-necked flask. The three-necked flask was placed in a microwave reactor equipped with a stirrer and a thermometer (thermocouple). Then, microwaves (2.45 GHz) were irradiated while stirring, and a transesterification reaction was performed for 5 hours while maintaining the temperature at 90 ° C. ± 2 ° C. After completion of the reaction, the mixture was purified using water, methyl ethyl ketone and ethyl acetate to obtain sucrose palmitate ester C.

  As Synthesis Example 4, sucrose palmitate ester D was obtained in the same manner except that the palmitic acid ratio was 50 mol% in the above synthesis step.

Comparative Example Normal Heating A three-necked flask was charged with 34 g of sucrose, 2 g of sucrose palmitate as an emulsifier, and 50 g of water, and completely dissolved by heating and stirring at 60 ° C. for 30 minutes. Further, 27 g of methyl palmitate was heated and melted at 60 ° C. and charged into a three-necked flask. The three-necked flask was placed in an oil bath, and a transesterification reaction was carried out for 30 hours while maintaining the temperature measured with a thermometer (thermocouple) at 90 ° C. ± 2 ° C. while stirring. In this comparative example, microwave irradiation was not performed. Further, the liquid during the transesterification reaction was a two-layer liquid. After completion of the reaction, the mixture was purified using water, methyl ethyl ketone and ethyl acetate to obtain sucrose palmitate ester a.

Examples 1-5 and Comparative Examples 1-5
Extracted with hot water (extraction efficiency 25%) using 60 g of roasted coffee beans with L value of 21 to a coffee extract with a Brix value of 3.0, milk, fresh cream, granulated sugar and polyglycerin fatty acid ester in 60 ° C hot water , Sodium caseinate and sucrose palmitate A, B, C, D, a solution was added, adjusted to pH 6.9 with sodium bicarbonate, water was added to make the total amount 1000 g, Table 1 It was set as the coffee mix of the mixture ratio described in (1). The weight-adjusted coffee mix was homogenized using a high-pressure homogenizer at a temperature of 65 to 75 ° C. and a pressure of 15 MPa, filled in a can container, and then subjected to retort sterilization at 121 ° C. for 30 minutes. The pH of the coffee mix after sterilization was 6.6.
The Brix value here means the solution-soluble solid content concentration, and is the weight (g) of soluble solids per 100 g of solution calculated using a saccharimeter, a refractometer or the like.

Examples 6-8 and Comparative Examples 6-8
30 g of roasted coffee beans with an L value of 21 was extracted with hot water (extraction efficiency 25%), a coffee extract with a Brix value of 3.0, milk, granulated sugar, polyglycerin fatty acid ester and hot water at 60 ° C. Add a solution in which one of the sugar palmitates A, B, C, D, and a is dissolved, adjust to pH 6.9 with sodium bicarbonate, add water to make the total amount 1000 g, and mix the proportions shown in Table 3 It was a coffee mix. The weight-adjusted coffee mix was homogenized using a high-pressure homogenizer at a temperature of 65 to 75 ° C. and a pressure of 15 MPa, filled in a can container, and then subjected to retort sterilization at 121 ° C. for 30 minutes. The pH of the coffee mix after sterilization was 6.6.

Examples 9-12 and Comparative Examples 9-13
Hot water extraction (extraction efficiency 25%) using 10 g of tea leaves with a black tea extract with a Brix value of 3.0, milk, fresh cream, granulated sugar, succinic monoglyceride and sucrose palmitate in 60 ° C hot water A solution in which any of A, B, C, D, and a was dissolved was added, adjusted to pH 6.8 with sodium bicarbonate, water was further added to a total amount of 1000 g, and a black tea mix with the blending ratio shown in Table 5 was obtained. . The black tea mix whose weight was adjusted was homogenized at a temperature of 65 to 75 ° C. and a pressure of 17 MPa using a high-pressure homogenizer, and then filled in a can container and sterilized by retort at 121 ° C. for 40 minutes. The pH of the black tea mix after sterilization was 6.5.

Examples 13-16 and Comparative Examples 14-18
Cocoa powder is dispersed in water, and a solution in which any of milk, fresh cream, granulated sugar, monoglyceride, and sucrose palmitate A, B, C, D, a is dissolved is added, and the pH is 7.0 with sodium bicarbonate. After adjustment, water was further added to make the total amount 1000 g, and a cocoa mix having a blending ratio shown in Table 7 was obtained. The cocoa mix whose weight was adjusted was homogenized at a pressure of 20 MPa at a temperature of 65 to 75 ° C. using a high-pressure homogenizer, and then subjected to retort sterilization at 121 ° C. for 60 minutes. The pH of the cocoa mix after sterilization was 6.7.

<Bacteriostatic test>
In the beverages of Examples 1 to 16 and Comparative Examples 1 to 18, the spore suspensions of Moorella thermoacetica, Thermoanaerobacter mathranii, and Geobacillus stearothermophilus activated at 100 ° C. for 30 minutes to a concentration of 1 × 10 ⁵ / ml Each of the spore suspensions was inoculated into 2 ml x 5 drinks in a glass tube, and the open end was sealed with a flame. After storing this at 55 ° C. for 4 weeks, the presence or absence of deterioration was determined. Judgment was made based on the difference in appearance and pH from the inoculation-free area. Tables 2, 4, 6 and 8 show the number of deterioration.

<Taste evaluation>
The beverages of Examples 1 to 16 and Comparative Examples 1 to 18 were tasted at room temperature in a room at 25 ° C., subjected to a sensory test, and evaluated according to the following criteria. The results are shown in Tables 2, 4, 6 and 8.
・ Natural taste ◎: Does not feel strange taste ○: Feels almost no strange taste △: Feels slightly strange taste ×: Feels strange taste

・ Milk flavor ◎: Feels a very rich feeling of milk ○: Feels a rich feeling of milk △: Slightly poor feeling of milk ×: Poor feeling of milk

  Comparing Comparative Examples 1-18 and Examples 1-16, coffee beverages, café au lait beverages, tea beverages, and cocoa beverages added with sucrose palmitate synthesized by microwave irradiation are excellent in flavor. Recognize. Even if the reaction mixture is purified in the same manner, it is presumed that there are few heat-degraded components that cause off-flavors by using microwaves. Further, when the palmitic acid ratio was 80%, the flavor was particularly good. In each beverage to which 50 ppm of sucrose palmitate was added, the growth of spore-forming heat-resistant bacteria could not be sufficiently suppressed. On the other hand, the coffee beverage added with 4000 ppm of sucrose palmitate was not preferable in terms of flavor. Further, a rich milk flavor was felt in a beverage having a milk solid content of 1.2% by weight or more.

  The present invention is not limited by the above-described embodiments and examples. Various embodiments can be taken without departing from the scope of the present invention.

  The present invention is useful in the field of milk beverages in sealed containers.

DESCRIPTION OF SYMBOLS 1 Chemical reaction apparatus 11 Pump 12 Mixing part 13 Reactor 14 Microwave generator 15 Waveguide 16 Microwave control part 17 Ultrasonic vibrator 18 Ultrasonic oscillator 19 Ultrasonic control part 20 Treatment liquid storage tank 21 Partition plate 22 Unfilled Space 25 Temperature measurement unit 30 Contents 31-33 Room

Claims (4)

Hereinafter, a milk beverage in a sealed container containing (A) and (B).
(A) Sucrose and sucrose fatty acid ester obtained by the manufacturing method including the process of irradiating microwave to the mixture containing fatty acid ester and / or fatty acid 0.01-0.3 wt%
(B) Milk solid content is 1.2 wt% or more   The milk beverage in a sealed container according to claim 1, wherein the milk fat content is 0.5% by weight.   The milk beverage in a sealed container according to claim 1 or 2, wherein 70 mol% or more of the constituent fatty acids of the sucrose fatty acid ester is palmitic acid.   The milk beverage in a sealed container according to any one of claims 1 to 3, wherein the milk beverage is one of milk coffee, milk tea, and cocoa.

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