JP2013233159A - Method for producing liquid nutritious food - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a more efficient and simplified method of producing liquid nutritious food such as liquid food and medical dietary food.SOLUTION: A method for producing liquid nutritious food includes a mixing step 12 of mixing raw materials, a sterilizing step 13 of carrying out heating treatment, and a homogenizing step 15 of carrying out homogenizing treatment, wherein a multifunctional tank capable of operating heating/cooling/stirring at least under reduced pressure is used as a mixing tank in the mixing step 12, and the average diameter of fat spheres is 1 μm or less.

Description

  The present invention relates to a liquid nutritional food such as liquid food / medical food and a method for producing the same.

  Conventionally, liquid nutritional foods such as liquid foods and medical foods have been used as nutritional supplements for patients after surgery, for example.

  In Japan, a country with a longevity, where the proportion of elderly people has increased in recent years, demand for liquid nutritional foods such as liquid foods and medical foods has increased in order to cope with poor nutrition intake due to mastication disorders and dysphagia.

  This liquid liquid food (enteral nutrition, tube feeding, etc.) is required to contain comprehensive nutrients such as vitamins, minerals, and fibers in addition to the inclusion of carbohydrates, lipids, and proteins. In addition to the taste, long-term quality maintenance that suppresses changes in physical properties such as fat flotation, water separation, sedimentation, and browning is required, and predetermined fluidity is also required in preparation for the use of tubes (tubes, etc.). There are many requests.

  In order to meet the above demands, it has a high solid content, is stable after heat treatment, has little precipitation and fat floatation, excellent long-term storage, and excellent fluidity through the tube. A method for producing a composition has been proposed (see Patent Document 1).

  In addition, thickening polysaccharides are added to prevent the formation of aggregated precipitates, but there is also a method for producing a concentrated liquid food having good tube fluidity by suppressing the decrease in fluidity caused by gelation caused by the thickening polysaccharides. It has been proposed (see Patent Document 2).

JP-A-11-332528 JP 2003-289830 A

  The production methods described in Patent Documents 1 and 2 above meet the demands required for liquid nutritional foods, but both require a high homogenization pressure in the homogenization process, and the raw material preparation process However, it is inevitable that the manufacturing cost and equipment cost will be large, such as requiring many operations and devices.

  FIG. 2 is a block diagram showing an example of a conventional liquid nutritional food production process including the production methods according to Patent Documents 1 and 2.

  As shown in FIG. 2, raw materials for total nutrition such as carbohydrates, proteins, and vitamins are inspected and weighed (S101), and charged into a mixing tank containing a predetermined amount of hot water at about 55 ° C. (S102). And in order to mix fats and oils stably and uniformly, fats and oils are proportionally inject | poured into the piping etc. in the post process of a preparation tank (inline mixing) (S103).

  Then, using a preliminary emulsifier (in-line homomixer), the proportionally injected fats and oils are mixed (S104).

  Thereafter, after a preheating step of about 85 ° C. (S105), a first homogenization step (homogeneous before the sterilization step) applied with a homogenization pressure for reducing the particle size of the liquid food (S106), and a sterilization step ( After the cooling process (85 ° C.) (S108) after the cooling process (85 ° C., 5 seconds) (S107), the second homogenous process (homogeneous after the sterilization process) (S109) is performed.

  Then, after the re-cooling process (10 ° C. or lower) (S110), the process continues to the filling process / shipment (S111).

  Thus, in the manufacture of liquid nutritional foods such as liquid foods and medical foods, many operations and facilities are required at each stage including the raw material preparation process and the homogeneous process.

  The present invention aims to improve the efficiency and simplification of a method for producing liquid nutritional foods such as liquid foods and medical foods, and to provide high-quality liquid nutritional foods.

  The present invention has reviewed the cooperation between the liquid nutritional food preparation process and the homogenization process, and has attempted to solve the above problems by selecting an optimal preparation tank and devising a method for using the same, and further adding a device for the homogenizer. It is a thing.

  That is, in order to achieve the above-described object, the present invention proposes a liquid nutritional food comprising a preparation process for preparing raw materials, a sterilization process for heat treatment, and a homogeneous process for homogeneous treatment. A manufacturing method using a multifunctional tank capable of heating, cooling and stirring at least in a reduced pressure (negative pressure) state for the preparation process of the preparation process, and an average fat globule diameter after the preparation process of 1 μm It is the manufacturing method of the liquid nutrition food characterized by the following.

  At this time, the lower the pressure in the decompressed state in the tank and the higher the degree of vacuum, the more efficiently the powder raw material is sucked into the tank and dissolved. This increases the effect of deodorization and defoaming as well as shortening the preparation time. However, in a product with high foamability (easy to foam), if the amount of liquid in the tank is large (the liquid level is high) and the head space is small, the foam overflows from the tank and the loss of the product increases. For example, since it is difficult to increase the head space in a small-capacity tank or the like compared to a large-capacity tank, it is difficult to set the degree of vacuum higher in a small-capacity tank or the like than in a large-capacity tank. Thus, care must be taken in setting the degree of vacuum in the tank.

  Therefore, for example, when the preparation process is performed at about 55 ° C. while suppressing the boiling of the preparation liquid, the reduced pressure is preferably −60 kPa or less (absolute pressure: 38 kPa (= 295 mmHg) or less, boiling at about 76 ° C. with water). More preferably, −70 kPa or less (absolute pressure: 28 kPa (= 218 mmHg) or less, boiling at about 69 ° C. with water), more preferably −80 kPa or less (absolute pressure: 18 kPa (= 140 mmHg) or less, about 59 with water. Boil).

  On the other hand, when the preparation process is performed with hot water at about 55 ° C. while evaporating and concentrating the preparation liquid, the reduced pressure state is −83 kPa or less (absolute pressure: 15 kPa (= 118 mmHg) or less, boiling at about 55 ° C. with water). Also good. The pressure in the reduced pressure state is a guideline, and when the preparation process is performed at about 60 ° C. or about 50 ° C., the pressure in the reduced pressure state can be appropriately adjusted and set while taking into account the pressure boiling at those temperatures. .

  In the method for producing the liquid nutritional food, a homogenous machine having a homogeneous disk or a multistage valve configured with a small gap is used for the homogenization of the homogenous process, and the average fat globule diameter after the homogenous process is 0.5 μm or less. It can be.

  In addition, the homogenization pressure in this homogenous process can be 50 Mpa or less.

  As described above, in the method for producing a liquid nutritional food of the present invention, an average fat globule diameter of 0. 0 MPa or less at a homogenization pressure at a real production scale of, for example, 6000 L / h is 50 MPa or less, which is a homogenization pressure lower than conventional. One of the characteristics is that the thickness is 5 μm or less.

  According to the method for producing a liquid nutritional food product of the present invention, a multifunctional tank capable of heating, cooling and stirring is used in the preparation step, for example, at least in a reduced pressure state, and in a homogeneous step, for example, a slight amount. By using a homogenous disk with a gap or a homogeneous machine with a multi-stage valve, it has become possible to improve efficiency and simplification in each process of manufacturing liquid nutritional foods such as liquid foods and medical foods. .

  In other words, by using the above-described multifunctional tank as a mixing tank, heating, cooling, and stirring operations can be performed collectively in a reduced pressure state. Defoaming, deoxygenation, deodorization, and homogenization of (raw milk) can be carried out efficiently in a short time.

  By carrying out heating, cooling, and stirring operations all at once in a reduced pressure state, the preparation liquid is defoamed (defoamed), and almost no gas (bubbles) is generated in the homogenization, sterilization, and filling processes after preparation. The liquid (preparation liquid) which does not contain can be processed. Therefore, the apparatus (equipment) of each process can be operated stably. Specifically, reducing the loss of preparation liquid, reducing the frequency of failure and parts replacement in each device, improving the dissolution effect and emulsification effect in a homogenizer, suppressing adhesion in a sterilizer, and cleaning The frequency can be reduced and the continuous operation time can be extended.

  In addition, heating, cooling, and agitation operations are performed collectively under reduced pressure to deoxygenate the prepared liquid, destroying or reducing nutrient components (vitamins, etc.) due to heating, enzyme action, etc. Loss can be suppressed. Furthermore, it has a deodorizing function that removes odors such as casein, which are considered to be unfavorable.

  In the multi-function tank, which is a compounding tank, the particle size of the raw material can be reduced by vigorous stirring, so the use of a pre-emulsifier can be omitted, and in the multi-function tank, fats and oils can be mixed and dispersed uniformly. Therefore, it can be charged together with other raw materials, and proportional injection (in-line mixing) of fats and oils is not necessary.

  At this time, as described above, the average fat globule diameter after the preparation step is preferably adjusted to 1 μm or less, more preferably 0.9 μm or less, and still more preferably 0.8 μm or less.

  By making the average fat globule diameter in the blending process smaller than the average fat globule diameter of commercially available milk (about 1 to 2 μm), the fats and oils are stabilized in the water phase in the sterilization process and the homogenous process that are the subsequent processes of the blending process. (Uniformly) and each manufacturing device can be operated stably. In the sterilization process, it is possible to suppress adhesion with a sterilizer, reduce the frequency of cleaning, extend the continuous operation time, and the like. In the homogeneous process, it is possible to improve the dissolution effect and emulsification effect in a homogenizer.

  In the multi-functional tank, since the powder raw material is automatically sucked into the dissolved water when placed in a reduced pressure state, the blending (dissolution) time can be shortened to about one-third that of the conventional one, saving labor. Can be Moreover, since the bubbles (generation of bubbles) in the preparation liquid are reduced, the defective dissolution of the powder raw material is reduced, and the centrifugal sedimentation amount (precipitation) of the preparation liquid is also reduced. Therefore, it is preferable to perform the preparation process in a reduced pressure state.

  In addition, the multi-functional tank can vigorously stir high-viscosity fluids, so that trace components can be mixed evenly, and deposits and sediment on the wall and bottom of the tank can be removed. Can be maintained in a good state.

  In the method for producing a liquid nutritional food according to the present invention described above, the homogenizer in the homogenization process has a homogenous disk or multistage valve configured with a small gap, so that the homogenization pressure is set lower than before. In the state, the emulsification effect reflected in the size of the fat globule diameter can be made equivalent to the conventional one.

  For example, by adopting a homogeneous disk and multistage valve in the homogenizer used after sterilization (second homogeneous process), the numerical value of the homogenization pressure is reduced to about three-quarters compared to the conventional, emulsifying effect. Can be made equivalent to the conventional one.

  However, these homogenous disks and single-stage valves cannot sufficiently reduce the homogenization pressure, and the homogenization pressure can be sufficiently reduced by the combined use with the above-described multifunctional tank (preparation tank).

  At this time, the average fat globule diameter after the homogenization step is preferably adjusted to 0.5 μm or less, more preferably 0.45 μm or less, and still more preferably 0.4 μm or less.

  That is, in the above-described homogeneous process in the method for producing a liquid nutritional food product of the present invention described above, at a real production scale, for example, 6000 L / h, a homogenization pressure lower than the conventional one is, for example, 50 MPa or less, preferably 40 MPa or less, more preferably. Is 35 MPa or less, more preferably 30 MPa or less, particularly preferably 25 MPa or less, and the average fat globule diameter after the homogenization step is 0.5 μm or less, for example, about 0.45 μm or 0.4 μm. One.

  By making the average fat globule diameter smaller than the average fat globule diameter (about 0.5μm) of commercially available liquid foods, oils and fats are stably (uniformly) dispersed in the aqueous phase even when the product is stored for a long period of time. However, there is little formation of precipitates and cream floating during storage of the product, and the quality is equal to or higher than that of conventional products.

  Here, as a homogenizer having a homogeneous disk or a multi-stage valve configured with a small gap, for example, an emulsifier (homogenizer) having a nanovalve (Niro Soavi) or a microgap (APV) is used. can do.

  These emulsifiers (homogenizers) having a nanovalve, microgap, etc. have a homogeneous disk or multistage valve constituted by a small gap of 20 to 80 μm, preferably 30 to 70 μm, more preferably 40 to 60 μm. And it can be used in the scale of the actual manufacture whose flow volume is about 6000 L / h.

  In conventional valves (Izumi Food Machinery Co., Sanwa Machinery Co., Ltd.) used on the scale of actual production, the gap between the homogeneous disk and the multistage valve is about 90 to 100 μm, whereas in the nano valve, 50 About 70 μm (about 60 μm), and in the micro gap, about 30 to 50 μm (about 40 μm).

  The gap between the homogeneous disk and multistage valve of the homogenizer used in the homogenization step in the production method of the present invention is as small as 20 to 80 μm, preferably 30 to 70 μm, more preferably 40 to 60 μm. The numerical value of this gap is derived from a calculation formula described later, and is supported experimentally and theoretically. The clearance between these homogeneous disks and multistage valves is a numerical value estimated and calculated from several assumptions and experimental results.

  In the method for producing a liquid nutritional food according to the present invention described above, examples of the multifunctional tank include a turbo mixer (Scanima: Turbo Mixer) and an equivalent multifunctional tank (Romaco Flyma Koruma: Dinex, APV). : Flex Mix etc.) can be used.

  These multifunctional tanks such as turbomixers have a rotor and a stator having a slit width of 1 to 7 mm in the tank.

  The rotor has a tank diameter of about 580 to 2500 mm and a tank height of about 400 to 2300 mm. For example, the diameter is 200 to 400 mm (radius is equivalent to 100 to 200 mm), and the rotational speed is 1000 to 3000 rpm.

  As a stator, for example, the slit width is 1 to 7 mm, preferably 2 to 6 mm, and more preferably 3 to 5 mm.

  The slit width means a short side or a short diameter when the gap (hole) is rectangular or elliptical, and means a diameter when the gap is circular.

  The movable stator is effective for stirring and atomization. Specifically, there is a dynamic stator (Scanima), and the stator moves up and down to switch between the circulation mode and the high shear mode. It is a system.

  The present invention further proposes a liquid nutritional food produced by the above-described method for producing a liquid nutritional food of the present invention.

  Here, the viscosity of the liquid nutritional food produced by the method for producing a liquid nutritional food of the present invention is preferably 15 to 100 cP.

  The method for producing a liquid nutritional food proposed by the present invention is suitable for producing a liquid food having a high concentration and a high viscosity, and the effect of the present invention is exhibited particularly at 15 cP or more. On the other hand, tube fluidity is required as a liquid food, and when the viscosity is 100 cP or more, it is difficult to flow through the tube (thin tube) during tube feeding. In addition, in this specification, a viscosity is a numerical value as a product below normal temperature.

  Moreover, as a composition of a liquid food, it is preferable that proteins are 30-100 mg / ml, lipids (oils and fats) are 20-100 mg / ml, and carbohydrates are 50-350 mg / ml, for example.

  In addition, according to the manufacturing method of the liquid nutritional food of this invention mentioned above, since a raw material can be mixed and processed in a short time by use of a multifunctional tank, a useful ingredient (for example, vitamin C) accompanying a heating, the action of an enzyme, etc. , B1, D, folic acid, etc.) can be provided. Moreover, since the holding time at high temperature can be shortened by a short preparation process, the growth of thermophilic bacteria can be suppressed and a liquid nutritional food can be produced.

  According to the present invention, an efficient liquid nutritional food can be produced in the preparation process and the homogeneous process. That is, since a multi-functional tank was used in the preparation process, proportional injection of fats and oils (in-line mixing), use of a preliminary emulsifier (in-line homomixer) and use of a homogenizer before sterilization (first homogenization process) are omitted. be able to.

  In addition, the particle size (fat globule diameter) can be made smaller than in the conventional manufacturing process by the blending process using the multi-functional tank. Can be lowered.

  Furthermore, according to the present invention, since the preparation process can be performed in a short time, it is possible to suppress the action of heating and enzymes, etc., and it is possible to produce a liquid nutritional food while minimizing the destruction or reduction of useful components. Similarly, since the retention time at high temperature can be shortened, the growth of thermophilic bacteria can be suppressed and a liquid nutritional food can be produced.

The block process drawing of the manufacturing method of the liquid nutrition food concerning the present invention. The block process figure of the manufacturing method of the conventional liquid nutritional food. The graph which showed the relationship between the preparation time (stirring holding time) and fat globule diameter (particle diameter) in a preparation process. The graph which showed the relationship between a homogenization pressure and a fat globule diameter (particle diameter). (A) Conceptual explanatory drawing of a strict model and a simplified model of shear stress in a homogeneous process. (B) A graph showing the relationship between shear stress and fat sphere diameter (particle diameter). (A) List of the number of high-temperature bacteria in a preparation process. (B) A list of the number of high-temperature bacteria in the preparation process. (A) The graph which showed the relationship between the preparation time (stirring holding time) and fat globule diameter (particle diameter) in a preparation process. (B) List of experimental conditions.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing an example of a method for producing a liquid nutritional food according to the present invention.

  As shown in FIG. 1, in the manufacturing process of liquid nutritional foods such as liquid foods and medical foods, raw materials are inspected and measured (S11). The raw materials vary depending on the use of liquid foods and medical foods. In general, in addition to carbohydrates, lipids and proteins, synthetic nutrients such as vitamins, minerals and fibers are included.

  The raw materials that have been inspected and weighed are put into a multi-function tank, which is a mixing tank in the mixing process, and mixed. This multifunctional tank contains a predetermined amount of hot water of about 55 ° C.

  In this embodiment, the multifunctional tank is a turbo mixer (manufactured by Scanima: Turbo Mixer). In this turbo mixer, the diameter of the tank is about 580 to 2500 mm and the height of the tank is about 400 to 2300 mm, whereas the diameter of the rotor is about 200 to 400 mm and the rotation speed is about 1000 to 2600 rpm, and the slit diameter Has a 4 mm stator in the tank. Since the stirring of the turbo mixer is strong, the raw materials can be mixed and dispersed in a predetermined uniform state in the tank.

  Therefore, fats and oils can be added simultaneously with the raw materials, and the proportional injection of fats and oils that has been performed in the conventional manufacturing process (in-line mixing, the block process of the conventional liquid nutritional food manufacturing method in FIG. Step) is unnecessary, and the equipment of the preliminary emulsifier can be omitted (S104 shown in FIG. 2).

  At this time, the decompressed state in the tank is used as -60 kPa (absolute pressure: 38 kPa) to -80 kPa (absolute pressure: 18 kPa), and the powder raw material and the like are efficiently sucked into the tank and dissolved. In the tank, the lower the pressure in the reduced pressure state and the higher the degree of vacuum, the more efficiently the powder raw material is sucked into the tank and dissolved. This increases the effect of deodorization and defoaming as well as shortening the preparation time. However, in a product with high foamability (easy to foam), if the amount of liquid in the tank is large (the liquid level is high) and the head space is small, the foam overflows from the tank and the loss of the product increases. For example, since it is difficult to increase the head space in a small-capacity tank or the like compared to a large-capacity tank, it is difficult to set the degree of vacuum higher in a small-capacity tank or the like than in a large-capacity tank. Thus, care must be taken in setting the degree of vacuum in the tank.

  The graph of FIG. 3 shows the relationship between the blending time (stirring holding time) in the blending process by the turbo mixer (SRB50), the particle diameter of the blended particles, and the homogenization pressure. It should be noted that the blending time here does not include the time for charging the powder raw material into the blending tank.

  As shown in FIG. 3, when mixed (stirred) for 15 minutes with a turbo mixer, the particle diameter (average fat globule diameter) becomes about 0.7 μm. The particle diameter (average fat sphere diameter) here is a measured value (volume average value) by SALD-2000J (Shimadzu Corporation).

  Here, referring to the conventional manufacturing process shown in FIG. 2, a pre-emulsifier is used immediately after the proportional injection of fats and oils (FIG. 2, S103) (FIG. 2, S104), and before and after sterilization. Are subjected to high-pressure treatment using a homogenizer (homogenizer) twice. At this time, the particle diameter of the raw material processed with the preliminary emulsifier was about 1.5 μm, and the particle diameter after processing in the first homogeneous process (homogeneous process before sterilization) was about 0.6 μm.

  Therefore, it turns out that a preliminary emulsifier becomes unnecessary by mixing for 15 minutes with the turbo mixer in the present Example. Furthermore, the particle diameter after processing in the first homogenous process (homogeneous process before sterilization) in the conventional manufacturing process is about 0.6 μm, whereas after blending for 15 minutes with the turbo mixer in this example Therefore, the first homogenous process (homogeneous process before sterilization) in the conventional manufacturing process may be omitted. The turbo mixer is merely an example, and other equivalent multi-functional tanks (Romaco Flyma Koruma: Dinex, APV: Flex Mix, etc.) can be used.

  Next, as described above, the raw material of the liquid nutritional food that has undergone the blending process by mixing with the turbo mixer omits the proportional injection of fats and oils and the use of the preliminary emulsifier in the conventional manufacturing process, and the sterilization process (145 (S14). This sterilization process is the same as the conventional manufacturing process.

  After passing through the sterilization step, homogenization at high pressure using a homogenizer (homogenizer) is performed (S15).

  Examples of the homogenizer (homogenizer) include a large-sized homogeneous disk having a small gap (Niro Soavi: Nano Valve) and a multistage valve having a large number of small gaps (APV: Micro Gap).

  That is, by using an emulsifier having a nanovalve or a micro gap, the homogenization pressure can be greatly reduced as compared with the conventional production process.

  The nanovalve and microgap are merely examples, and other equivalent disks and valves can be used with the gap set to a predetermined value.

  Specifically, referring to the graph showing the relationship between the homogenization pressure and the particle diameter in FIG. 4, the fat globule diameter of the liquid nutritional food when the second homogenization pressure is treated at 40 MPa in the conventional homogenization process In order to make it equal to (particle diameter: about 0.4 μm), the homogenization pressure in the homogenization process of this example was determined. As a result, it is proved that the homogenization pressure in this embodiment may be about 23 MPa.

  Therefore, the liquid nutritional food having a particle size of about 0.4 μm by the homogenization process (S15) is subjected to a cooling process (S16), followed by a filling process and shipping (S17).

  As described above, in the production process of the present embodiment in the method for producing a liquid nutritional food according to the present invention, the number of steps and the number of production equipment used can be reduced as compared with the conventional production process of a liquid nutritional food.

  That is, in the production of a liquid nutritional composition such as a liquid food, it is essential to prevent emulsion breakage, and it is very important to atomize fat globules and stabilize emulsion by pre-emulsification and homogenization. Therefore, in the conventional manufacturing process, the following three operations (treatments) have been indispensable in order to improve atomization of fat globules and stabilization of emulsification.

  (1) Inline proportional injection of fats and oils and mixing / dispersion (preliminary emulsification treatment) by a pre-emulsifier (in-line mixer): It is necessary not to add oils and fats excessively to the protein.

  (2) Homogenization (atomization treatment) by the first (before sterilization) homogenizer (homogenizer): Necessary as a pretreatment in order to improve the emulsified state after sterilization (heat treatment).

  (3) Homogenization (emulsification treatment) by a second (after sterilization) homogenizer (homogenizer): high-pressure treatment is required to prevent the cream from being floated or precipitated during storage.

  In the case of producing a liquid nutritional product having a relatively high concentration and high viscosity (for example, Maybalance 1.5HPZ manufactured by Meiji Dairies Co., Ltd., viscosity: 20 to 35 cP) using this conventional production process, the average fat globule The diameter is about 15 μm after the pre-emulsification process (in-line mixer, step (1) above), and about 0.6 μm (homogenization after the atomization process (first homogenizer, step (2) above)). Pressure: 15-30 MPa), and after the emulsification treatment (second homogenizer, step (3) above), the pressure is about 0.4 μm (homogenization pressure: 40-50 MPa).

  On the other hand, when Maybalance 1.5ZCS (viscosity: 10 to 20 cP) was prepared using a multifunctional tank (Skanima Inc .: SRB50, turbo mixer), the elapsed time and the particle size of the end of preparation (completion) The relationship is shown in FIG. In this turbo mixer, the tank diameter is about 580 mm, the tank height is about 400 mm, the rotor diameter is 200 mm, the rotor rotation speed is 2000 rpm, the slit diameter is 4 mm, the feed amount is 40 L, and the scale of the pilot plant (model: model: SRB50). The decompressed state in the tank is −60 kPa (absolute pressure: 38 kPa).

  From FIG. 3, it can be confirmed that the average particle diameter becomes about 0.77 μm 15 minutes after the completion of the charging of the powder raw material and the like. In other words, if the preparation liquid is held in the tank for 15 minutes while circulating the rotor and stator installed in the lower part of the multi-function tank (turbo mixer), the average fat globule diameter can be reduced to about 0.7 μm only by the preparation operation. It became clear that atomization was possible.

  About this preparation liquid (average fat globule diameter: about 0.7 μm), in order to further atomize the fat globule, using a homogenizer (Nirosoabi: NS-3024H, sharp edge, treatment flow rate: 250 L / h), Emulsification was performed at 40 to 50 MPa. As a result, the average particle size was about 0.4 μm, which was the same as in the case of the conventional manufacturing method (FIG. 2).

  In the conventional manufacturing method (FIG. 2), in addition to the operation of mixing (stirring and mixing powder raw materials) in the tank, (1) proportional injection of fats and oils in-line and in-line mixer (preliminary emulsification treatment), (2 ) Homogenization (atomization treatment) with the first (before sterilization) homogenizer (homogenizer), (3) Homogenization (emulsification) with the second (after sterilization) homogenizer (homogenizer) A nebulization operation (three emulsifiers) was required.

  On the other hand, by using the production method of the present invention using a multi-functional tank, a relatively high concentration and high viscosity product (for example, May balance 1.5HPZ of Meiji Dairies Co., Ltd., viscosity: 20 to 35 cP) In the case of manufacturing, in addition to the blending operation in the multifunctional tank, one stage (one emulsifying device) of the atomization treatment corresponding to the second (after sterilization) homogenizer (homogenizer) is sufficient, The quality was the same as before.

  That is, it became clear that the two-stage atomization operation (two emulsifiers) can be omitted in total of the in-line mixer (preliminary emulsification treatment) and the first (before sterilization) homogenizer (homogenizer).

  Next, the relationship between the homogenization pressure and the particle diameter in FIG. 4 will be described in detail.

  In a homogeneous valve (homogeneous disk or multistage valve configured with a small gap) having a narrow flow path diameter (gap) used on an actual production scale, the gap is 30 to 60 μm (homogenization pressure: 40 to 60 MPa, processing flow rate: 6000 L / h), and a homogenizer provided with a homogeneous valve having a narrow flow path diameter is applied to the liquid food.

  In the conventional (normal) homogeneous valve used on the scale of actual production, the gap is 90 to 100 μm (homogenization pressure: 40 to 60 MPa, treatment flow rate: 6000 L / h). In other words, the homogeneous valve having a narrow flow path diameter has a flow path diameter (gap) of about ½ (1/2) compared to a conventional homogeneous valve.

  When fluid (liquid) is passed through such a narrow gap, it is expected (imagined) that the pressure becomes higher than usual. However, with nanovalves (homogeneous valves with a narrow flow path diameter), the flow path diameter of the valve body (within the valve housing) is increased (the valve diameter is increased), and the flow diameter of the working (wetted) part is reduced as much as possible. By shortening the flow path length, the pressure is made lower than usual to efficiently apply force (shear stress) to the fluid.

  On the other hand, in the micro gap (homogeneous valve having a narrow flow path diameter), the flow path of the valve main body (in the valve housing) is branched in parallel (for example, five). By dividing the fluid into these branch channels and reducing the flow rate at each branch, the channel diameter of the working (wetted) part is made as narrow as possible, while the pressure is made lower than usual and the force is efficiently applied to the fluid. (Shear stress) is applied.

  That is, in either case of nanovalves or micro gaps, it is important to devise how to reduce the pressure and allow fluid to pass through narrow gaps. Because of this ingenuity, the flow rate (linear velocity) of the action (wetted) part is slower in the nanovalve and microgap than in the conventional (normal) homogenizers (Izumi Food Machinery, Sanwa Machinery, etc.). Yes.

  Using a conventional homogenizer equipped with a normal valve (homogenizer) and a homogenizer equipped with a homogeneous valve with a narrow channel diameter, the liquid food “Maybalance 1.5ZCS (viscosity: 10 to 20 cP) (manufactured by Meiji Dairies) ) "Was homogenized with the processing capacity of the actual machine (6000 L / h).

  As a pretreatment, using a first homogenizer (Sanwa Machinery Co., Ltd .: H100), the liquid food is homogenized (homogenization pressure: 25 MPa, treatment flow rate: 6000 L / h), and then directly heated (Iwai Machine) Company: SN50) was used to sterilize the liquid food (145 ° C., 5 seconds) and then cool (about 85 ° C.).

  Using a normal valve (Izumi Food Machinery Co., Ltd .: HV-5EH, flat type homogeneous valve) and a homogeneous valve with a narrow channel diameter (Niro Soabi Co .: Nanovalve), the liquid food processed as described above is homogeneous. Treated and compared the effect of atomization.

  In FIG. 4, when the homogenization pressure is homogenized at 40 MPa using a normal valve (flat type), the particle diameter becomes 0.43 μm. On the other hand, in order to set the particle diameter to 0.43 μm using a homogeneous valve (nanovalve) having a narrow channel diameter, the homogenization pressure may be about 23 MPa. In other words, the narrow gap valve can reduce the homogenization pressure by about 35% compared to a normal valve.

  Here, the relationship between the homogenization pressure and the shear stress applied to the valve (homogeneous valve) of the homogenizer is expressed by a simplified model shown in FIG. Since it is difficult to calculate the shear stress strictly, the shear stress was estimated using the simplified model shown in FIG. FIG. 5A is a conceptual explanatory diagram of a strict model and a simplified model of the shear stress in the homogeneous process, and FIG. 5B is a graph showing the relationship between the shear stress and the particle diameter.

  It was assumed that the particle diameter would be equivalent if the shear stress was equivalent, but the basis for this assumption is obtained from the experimental result (actual measurement value) shown in FIG. Here, an experiment was conducted on an eight-fold scale-up in which the flow rate of 50 L / h was changed to 400 L / h. It was estimated that there was a correlation between shear stress and particle size between homogenizers with different flow rates. The shear stress is estimated based on the above-described theory.

According to the calculation result of this theory, in order to make the fat sphere diameter (particle diameter) of the second homogenizer about 0.4 μm in the conventional homogeneous process, the “shear stress” of the homogeneous valve is set to 20 × 10 ⁴ N / there needs to be about m ^2. And in order to make the particle diameter after the homogenization process by the homogenizer in the homogenization process in the present embodiment about 0.4 μm, the homogenization pressure should be about 26 MPa.

  There is a slight error between the actual measured value of 23 MPa and the calculated value of 26 MPa, but the homogenous machine's homogeneous pressure can be reduced by applying a nano-valve or microgap to the homogenizer after applying the turbo mixer to the compounding tank. Could be proved theoretically.

  Thus, according to the manufacturing method of the liquid nutritional food in the present embodiment, since the turbo mixer was used as a multifunctional tank in the raw material preparation step, it was possible to perform strong stirring as compared with the conventional preparation tank, Can be mixed with raw materials at the same time. And both the conventional proportional injection (in-line mixing) of fats and oils and the use of a pre-emulsifier accompanying this became unnecessary.

  For this reason, it has become possible to efficiently produce high-concentration and high-viscosity liquid nutritional food (such as liquid food) in a short time. Compared with the preparation (raw material dissolution) operation by the circulation type powder dissolving apparatus or the one-pass (one-through) type powder dissolving apparatus which is a conventional apparatus, the multifunctional tank (for example, a turbo mixer, etc.) according to this embodiment is used. In the blending operation, the blending time can be shortened and the number of staff members involved in the blending operation can be reduced. This point will be described in more detail below.

  In the conventional circulation type powder dissolving apparatus (Comparative Example 1), at the start of the dissolving operation, the amount of powder to be added to the dissolving solution is small and the concentration of the dissolving solution is low. The dissolution rate of the body is high.

  However, as the dissolution operation proceeds, the amount of powder added to the solution increases, and when the concentration of the solution increases, the viscosity of the solution increases and the dissolution rate of the powder decreases.

  At this time, when the viscosity of the solution increases, the circulation flow rate also decreases as a whole, and the dissolution rate of the powder becomes extremely small.

  In addition, since there are many circulation lines (lines) in the circulation type, when producing several types (batch) of products per day, the risk of bacterial growth in this line increases.

  When producing 10 kL of a relatively high-concentration and high-viscosity product (for example, Maybalance 1.5HPZ, viscosity: 20 to 35 cP by Meiji Dairies) using this circulation type powder dissolving apparatus, It takes about 100 minutes to complete the operation. Moreover, when manufacturing these comparatively high concentration and high viscosity products, it takes 4 persons / 8 hours as the arrangement personnel.

  On the other hand, the conventional one-pass (one-through) type powder melting apparatus (Comparative Example 2) uses a melting machine (Funken Co., Ltd .: Flow Jet Mill) that is particularly excellent in powder dispersibility, so that conventional circulation is possible. This solves some of the problems of the powder melting device. In other words, the 1-pass method can eliminate the decrease in the dissolution rate of the powder and can dissolve the powder in a higher concentration in a shorter time.

  However, in this one-pass blending operation, all powder raw materials except minerals must be charged in a time for feeding a predetermined amount of dissolved water.

  In addition, in this one-pass blending operation, it is necessary to push the pipes (lines) with water (rinse with water) after all of the powder raw materials have been added, limiting the amount of fresh water for dissolving the powder raw materials. However, it is necessary to leave fresh water for water pushing. For this reason, in a powder dissolver, it is necessary to dissolve proteins at a considerably higher concentration than the actual product, which increases the risk of poor dissolution.

  In the addition of fats and oils, the conditions in the blending operation are more severe, and all the fats and oils must be added (injected) and stably emulsified while the proteins are dissolved.

  At this time, the fats and oils must be introduced at a considerably high concentration in proportion to the concentration of the proteins. It is difficult to obtain a stable emulsified state by introducing high-viscosity fats and oils into a high-concentration protein solution at a high mixing ratio.

  In addition, since this one-pass powder dissolver cannot be cleaned in place (CIP), it must be manually cleaned (hand-washed), which requires labor and time for cleaning.

  And from the viewpoint that high-viscosity fats and oils must be quantitatively added to a high-concentration solution, a MONO pump must be used as a pump for liquid feeding. The MONO pump requires a cleaning pipe (line) as a bypass in addition to the manufacturing pipe (line), and is not a very convenient pump in consideration of the management of the rotor and stator.

  When producing 10 kL of a relatively high-concentration and high-viscosity product (for example, Meiji Dairy's Maybalance 1.5HPZ, viscosity: 20 to 35 cP) using this one-pass powder dissolving device, Approximately 80 minutes are required to complete the blending operation. Moreover, when manufacturing these comparatively high concentration and high viscosity products, it takes 4 persons / 8 hours as the arrangement personnel.

  The liquid nutrition food preparation operation in the present embodiment uses a multi-functional tank (for example, a turbo mixer), and this multi-functional tank has a rotor and a stator installed at the bottom of the tank. Agitation, mixing, emulsification, and dispersion are promoted by passing the solution (treatment liquid) through the rotor and the stator. A specific example of this blending operation will be described below.

  Fresh water (dissolved water) is put into the tank, and powder raw materials (powder) are charged when the liquid level (level) is reached. When dextrins and fats and oils are in a liquid state, dextrins and fats and oils can be charged simultaneously with the operation of adding fresh water to the tank.

  In addition, minerals can be added simultaneously with the operation of dissolving the proteins. At this time, most of the blending operation is completed at the same time as the charging of the powder raw material is completed. In order to stabilize the composition and physical properties of the dissolution liquid (treatment liquid) or to sufficiently degas the dissolution liquid (treatment liquid), the dissolution liquid (treatment liquid) can be held for an arbitrary time.

  In the blending operation in the multifunctional tank, the inside of the tank is decompressed, and the decompression effect allows the powder to be sucked into the inside of the tank and the solution.

  Therefore, in the circulation-type blending operation, as the viscosity of the solution (treatment) increases, the powder is less likely to penetrate (intrude) or disperse into the solution, and thus the problem is that the powder dissolution rate decreases ( However, in the blending operation in this multi-functional tank, the dissolution rate of the powder does not decrease with the increase in the viscosity of the solution.

  Furthermore, in the blending operation in the multi-functional tank (this example), unlike the conventional circulation type apparatus (Comparative Example 1), the piping for circulation in the entire manufacturing process such as the blending process and the liquid feeding process (line) ), The risk of bacterial growth is reduced even during continuous production for a long time.

  In addition, in the blending operation (this example) in the multi-function tank, unlike the conventional one-pass type device (Comparative Example 2) described above, the amount of fresh water for pushing water in pipes (lines) is reduced. The amount of fresh water for dissolving body materials can be increased.

  That is, it is not necessary to dissolve proteins at a high concentration, and the risk (risk) of poor dissolution is reduced. In addition, the addition of fats and oils eliminates the time limitation and makes it easier to obtain a stable emulsified state.

  The multi-function tank is easy to clean and can be cleaned in place (CIP). For this reason, in addition to reducing the risk of bacterial growth, hand washing as in the conventional one-pass type powder dissolver described above is completely unnecessary, and the burden of daily cleaning work is reduced.

  In the case of producing 10 kL of a relatively high concentration and high viscosity product (for example, May balance 1.5 HPZ, viscosity: 20 to 35 cP of Meiji Dairies) using the multifunctional tank used in this example. It takes about 30 to 40 (about 35) minutes to complete the powder dissolution (preparation) operation.

  In this multi-functional tank, containers for dextrins (carbohydrates) and powder mixers (powder silos) for proteins can be used together. When manufacturing these relatively high-concentration and high-viscosity products, , 2 persons / 8 hours are required as the arrangement staff.

  In other words, by using a multi-functional tank for the blending operation, it is possible to improve the efficiency of various incidental facilities, so the blending time is about 1/3 (1/3) that of the conventional circulation type apparatus described above, Compared to the conventional one-pass device, the number of personnel involved in the blending operation can be reduced to about ½ compared to the conventional circulation device and one-pass device described above. It can be reduced to (1/2).

  Furthermore, since the multifunctional tank can remove deposits and sediment on the inner surface of the tank by vigorous stirring, the heat transfer properties of the wall surface and the bottom surface can be maintained in a good state.

  Furthermore, the use of a turbomixer with strong stirring power that collectively performs heating, cooling, and stirring operations under reduced pressure provides a preparation liquid that contains almost no bubbles, thus improving the effect of dissolution and emulsification. .

  Moreover, since the dissolution in the preparation process can be performed with high efficiency, the preparation work can be saved. And it can bring deoxygenation effect to the preparation liquid, and it can suppress the destruction and decrease of nutritional components (for example, vitamin C, vitamin B1, folic acid, vitamin D, etc.) due to heating, enzyme action, etc. The quality of the liquid nutritional food manufactured by the manufacturing method in an Example can also be aimed at.

  It is possible to suppress the destruction and reduction of nutrients and useful ingredients associated with heating and the action of enzymes, etc. in a short time with a multi-function tank (for example, a turbo mixer) in this embodiment. In this case, it was also confirmed from an experiment in which the content of vitamin C in the preparation liquid was measured over time when held at a predetermined temperature for a predetermined time.

  In this experiment, a liquid preparation “Maybalance 1.5HPZ (viscosity: 20 to 35 cP)” (manufactured by Meiji Dairies) was held at 50 ° C. with stirring by a three-one motor (rotation speed: 200 rpm) The content of C is confirmed over time.

  Vitamin C (VC) was added to this preparation liquid so that it might become 48 mg / 100 ml, and the sample (preparation liquid) was extract | collected temporally after 0 to 4 hours, and the density | concentration of vitamin C was measured. The standard value of “Maybalance 1.5HPZ” is 24 mg / 100 ml of vitamin C, and 48 mg / 100 ml, which is the experimental condition of this time, is increased by 200%.

  According to the results of this experiment, the content of vitamin C (VC), which was initially 36.4 mg / 100 ml (elapsed time 0 hours), was 31.0 mg / 100 ml after 1 hour and 24 hours after 2 hours. .8 mg / 100 ml, it has been confirmed that it becomes 18.2 mg / 100 ml after 3 hours, and 14.8 mg / 100 ml after 4 hours. From this experiment, it was found that vitamin C deteriorates when the preparation liquid (liquid food) is held at a predetermined temperature for a predetermined time.

  That is, it has been found that shortening the preparation time is an effective means for suppressing destruction and deterioration of useful components.

  The viscosity of the liquid nutritional food is preferably 15 to 100 cP. The method for producing a liquid nutritional food proposed by the present invention is suitable for producing a liquid food having a high concentration and a high viscosity, and the effect of the present invention is exhibited particularly at 15 cP or more. On the other hand, tube fluidity is required as a liquid food, and when the viscosity is 100 cP or more, it is difficult to flow through the tube (thin tube) during tube feeding.

  Powerful agitation with a turbomixer can reduce the particle size of the raw material compared to conventional blending tanks, so large homogenous disks with small gaps (Niro Soavi: Nanovalve) and multistage valves can be used in the homogenizer in the subsequent homogenization process. (APV: Microgap), that is, by using an emulsifier having a nanovalve or a microgap, it is possible to significantly reduce the homogenization pressure as compared with the conventional production process.

  In addition, as described above, in this embodiment, since the turbo mixer as a multifunctional tank is used in the blending process, the blending process can be performed in a lump without using any other powder dissolver or pump. By simply cleaning and managing the tank of the turbo mixer as a multifunctional tank, the risk (risk) of the growth of thermophilic bacteria can be reduced.

  In conventional blending equipment, the blended liquid (formulated milk, mix) remains not only in the tank but also in the mechanical seal portion of the powder dissolver and pump. Due to the remainder of this formulation, as the production is repeated (the more batches are added), the possibility of bacterial contamination increases. However, in the blending facility of the present invention, all blending operations can be completed with only a tank without using a powder dissolver or a pump. Therefore, if only the tank can be washed sufficiently, there is an advantage that the risk of growth of thermophilic bacteria is reduced.

  Actually, using a turbo mixer (Skanima: SRB50, charge amount: 40 L) as a multifunctional tank, a concentrated solution (1.5 times) of May balance C was continuously prepared to grow bacteria (increase). The tendency (situation) of (bacteria) was confirmed over time before and after washing (rinsing). 6 (a) and 6 (b) are a list of the number of high-temperature bacteria in the preparation process. According to this result, a tendency of enrichment was observed after 9 hours of preparation.

  At this time, the tank was rinsed manually with warm water using a hose, but a tendency of enrichment was observed thereafter (Study 1). On the other hand, it has been found that the increase in bacteria can be suppressed by sufficiently rinsing the tank with warm water automatically for about 5 minutes using a shower ball (Study 2).

  In Study 1, the mixture was continuously prepared for a long time using a turbo mixer. At this time, the growth of mesophilic bacteria, mesophilic spore bacteria, thermophilic bacteria, and thermophilic spore bacteria was confirmed. The result of Study 1 is shown in the list of FIG. As shown in this list, even if rinsing with warm water using a hose, bacterial growth could not be suppressed.

  In Study 2, based on the results of Study 1, the cleaning method was improved. At this time, the growth of mesophilic bacteria, mesophilic spore bacteria, thermophilic bacteria, and thermophilic spore bacteria was confirmed. The result of Study 2 is shown in the list diagram of FIG. As shown in this list, bacterial growth could be suppressed by rinsing the tank with warm water for 5 minutes using a shower ball. This can be easily recognized by comparing the number of high-temperature bacteria after holding for 9 hours and the number of high-temperature bacteria after holding for 12 hours after washing with a shower ball.

  Next, as other examples, liquid food Maybalance 1.5ZCS (viscosity: 10 to 20 cP) and Maybalance 1.5 HPZ (viscosity: 20 to 35 cP) which are liquid nutritional foods described in the above examples are higher. The manufacturing process of May Balance 2.0 (viscosity: 30 to 70 cP) of Meiji Dairies Co., Ltd., which is a product with high viscosity at a concentration, will be described.

  Using a multi-functional tank (Skanima Inc .: SRB50 and SPM3000, turbo mixer), May Balance 2.0 was prepared with a 1.3 times concentrated solution. FIG. 7A shows the relationship between the preparation time (stirring holding time) and the fat sphere diameter (particle diameter).

  May balance 2.0 (2.0 kcal / ml) is a product having a higher concentration and higher viscosity than May balance 1.5ZCS (1.5 cal / ml) as described above. At this time, in order to confirm the stirring effect (action) of the multifunctional tank for the product with higher concentration and higher viscosity, the amount of fresh water (dissolved water) in the blending operation is reduced, and Maybalance 2.0 is set to 1.3. It was decided to prepare with a double concentrated solution. That is, in order to evaluate the mixing performance of the multifunctional tank, a concentrated liquid (about 55 ° C.) 1.3 times as large as May Balance 2.0 was used as a simulation liquid. The simulated solution was prepared by adding only carbohydrates, proteins, fats and oils, without adding minerals and vitamins. By the way, in liquid nutritional compositions such as liquid foods, May Balance 1.0 (1.0 kcal / ml) is a standard concentration and is a highly versatile product.

  The experimental conditions are as shown in FIG. 7 (b). The charged amounts are 40L (model: SRB50) and 3000L (model: SPM3000), the rotational speeds are 2000rpm (model: SRB50) and 1200rpm (model: SPM3000), and the rotor diameter. Are 200 mm (model: SRB50) and 300 mm (model: SPM3000), the slit diameter is 4 mm (model: SRB50 and SPM3000), and the scale of the pilot plant (model: SRB50) and actual machine (model: SPM3000).

  At this time, the depressurized state in the tank was used as -60 kPa (absolute pressure: 38 kPa) for SRB50 and -80 kPa (absolute pressure: 18 kPa) for SPM3000. Since the head space is smaller in the SRB50 than in the SPM3000, it is difficult to set the degree of vacuum higher in the SRB50 than in the SPM3000.

  It was revealed that the average fat globule diameter could be atomized to about 0.8 μm only by the preparation operation if the preparation liquid was held for 10 minutes in a tank (model: SRB50) of a pilot plant scale. Further, it was revealed that the average fat globule diameter could be atomized to about 0.9 μm only by the blending operation if the blended solution was held for 5 minutes in a tank of the actual scale (model: SPM3000).

  That is, in any case of the pilot plant and the actual machine, if the preparation liquid is held in the tank for 5 to 10 minutes while circulating the rotor and the stator after the preparation (raw material dissolution), the average fat globule can be obtained only by the preparation operation. It became clear that the diameter can be reduced to about 0.9 μm.

  About this preparation liquid (average fat globule diameter: about 0.9 micrometer), in order to further atomize a fat globule, it emulsified at 40-50 Mpa using the homogenizer (Niro Soabi company: NS-3024H). As a result, the average particle size was about 0.4 μm, which is equivalent to the case of the conventional manufacturing method.

  When manufacturing a product with a high concentration and high viscosity (for example, Meiji Dairies' Maybalance 2.0) using a manufacturing method using a multifunctional tank, in addition to the blending operation in the multifunctional tank, In one stage (one emulsifier) of the atomization process corresponding to a homogenizer (after sterilization), the quality was equivalent to that of the prior art, which was sufficient. That is, it became clear that the two-stage atomization operation (two emulsifiers) can be omitted in total of the in-line mixer (preliminary emulsification treatment) and the first (before sterilization) homogenizer (homogenizer).

S11 Preparation process (feeding raw materials to turbo mixer, mixing, stirring)
S15 Homogeneous process

Claims (6)

A method for producing a liquid nutritional food comprising a preparation process for preparing raw materials, a sterilization process for heat treatment, and a homogeneous process for homogeneous treatment,
Liquid nutrition characterized by using a multifunctional tank capable of heating, cooling and stirring at least in a reduced pressure state for the blending process of the blending process, and having an average fat globule diameter of 1 μm or less after the blending process A method for producing food.  A homogenous machine having a homogeneous disk or a multistage valve configured with a small gap is used for the homogenization of the homogenization process, and the average fat globule diameter after the homogenization process is 0.5 μm or less. A method for producing a liquid nutritional food according to claim 1.  The method for producing a liquid nutritional food according to claim 2, wherein the homogenizer is an emulsifier having a homogeneous disk or a multistage valve constituted by a small gap of 20 to 80 µm.  The liquid multifunctional food production according to any one of claims 1 to 3, wherein the multifunctional tank is a blending tank having a rotor and a stator having a slit width of 1 to 7 mm in the tank. Method.  A liquid nutritional food produced by the method for producing a liquid nutritional food according to any one of claims 1 to 4.  The liquid nutritional food according to claim 5, wherein the liquid nutritional food has a viscosity of 15 to 100 cP.

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