JP6928272B2 - Frozen spherical food and method for manufacturing frozen spherical food - Google Patents

Description

The present invention relates to a frozen spherical food having a calcium alginate film and a method for producing the same.

Conventionally, a technique for producing a spherical food using a calcium alginate film has been known. The calcium alginate film has been used for fish egg-like foods, raw egg yolk-like processed foods, and the like because it has water retention, elasticity, and an appropriate breaking stress that can be bitten by teeth.
Patent Document 1 describes a method of obtaining a roe-like food by dropping a sol-like substance containing calcium chloride into an aqueous solution of an alkali metal alginate to form a calcium alginate film.
Patent Document 2 describes a raw egg yolk-like processed food having a portion corresponding to the yolk membrane composed of a calcium alginate film.

Japanese Unexamined Patent Publication No. 2004-215536 Japanese Unexamined Patent Publication No. 2009-131215

The calcium alginate film is required to have a glossy appearance as if it were covered with a layer of water even after freezing and thawing, such as the fetal membrane of a fresh roe or the yolk membrane of a raw egg. Has been done. However, with the conventional technique, it has been difficult to stably develop preferable moisturizing and glossiness for the calcium alginate film after freezing and thawing.

In view of the above circumstances, an object of the present invention is to provide a frozen spherical food having a glossy appearance covered with a layer of water and a method for producing the same.

As a result of diligent research to achieve the above object, the present inventors, by adding a predetermined thickening polysaccharide to the film containing calcium alginate of a frozen spherical food, make them feel abundant water even after thawing. It has been found that a frozen spherical food having a glossy and preferable appearance can be stably obtained.
Furthermore, the present inventors have found a thickening polysaccharide suitable for stably expressing a unique texture such as a water film on the surface of a film containing calcium alginate, and completed the present invention. I came to do it.

That is, the present invention
(1) A frozen spherical food having a film covering the inclusions.
The film contains calcium alginate and a thickening polysaccharide (excluding a film containing only modified starch, only cross-linked starch, and only modified starch and cross-linked starch).
After moving the frozen spherical food to room temperature (25 ° C.) and allowing it to stand for 3 hours to thaw, the frozen spherical food is allowed to stand on a flat plate to perform imaging satisfying the following (1-1) to (1-5). Under the condition (1), the following analysis conditions (2-1) to (2-3) (2) are used from each of the plurality of images taken by partitioning the entire surface of the film with a digital microscope using a visual analyzer. The number of pixels of the largest glossy mass among the glossy masses extracted in) is 20000 pixels or more.
^{A frozen spherical food having an area of 144 mm 2} or more projected on a projection plane substantially parallel to the flat plate.
[Imaging conditions (1)]
(1-1) Lens used: Ultra-compact high-performance zoom lens (magnification 20-200) Model number VH-Z20R (manufactured by KEYENCE CORPORATION)
(1-2) Magnification of the lens: 20 times (1-3) Shutter speed: 1/120 sec
(1-4) Gain: 6db
(1-5) White balance: 2700K
[Analysis condition (2)]
(2-1) Color space used for analysis: HSV color space (2-2) Numerical range of gloss in HSV color space ・ H (hue): 0 to 180 (maximum selectable numerical range: 0 to 180)
-S (vividness): 0 to 65 (maximum selectable numerical range: 0 to 255)
-V (brightness): 110-255 (maximum selectable numerical range: 0-255)
(2-3) In the pixels extracted as the gloss, the shortest distance between each pixel and another pixel for being excluded from the gloss mass: 1 pixel or more (2) The frozen sphere according to (1). It ’s food,
A frozen spherical food in which the thickening polysaccharide is hydroxypropyl starch.
(3) A method for producing a frozen spherical food having a film covering the inclusions.
A step of preparing a film-forming aqueous solution containing an alkali metal alginate and a thickening polysaccharide (excluding a film-forming aqueous solution containing only modified starch, only cross-linked starch, and only modified starch and cross-linked starch).
A step of immersing a hemispherical cup filled with a filling material for forming inclusions containing calcium ions in the aqueous solution for forming a film, and a step of immersing the hemispherical cup.
A step of forming the film containing calcium alginate and the thickening polysaccharide on the surface of the inclusion-forming filler by holding the hemispherical cup in the film-forming aqueous solution.
A method for producing a frozen spherical food containing.
(4) The method for producing a frozen spherical food according to (3).
A method for producing a frozen spherical food in which the content of the thickening polysaccharide in the aqueous solution for forming a film is 0.5% or more.
Is.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a frozen spherical food having a glossy appearance as if it is covered with a layer of water, and a method for producing the same.

Hereinafter, the present invention will be described in detail. In the following description, "%" indicates a mass%, and "part" indicates a mass part.

<Frozen spherical food>
The frozen spherical food of the present invention is a spherical food formed spherically by a calcium alginate film covering the inclusions, and is frozen and stored at −15 ° C. or lower. The sphere of the present invention includes not only a sphere but also an elliptical sphere close to a sphere such as a raw egg yolk, a flat sphere, and the like.
The spherical food of the present invention includes a calcium alginate film, a lumen formed inside the film, and a liquid or sol-like inclusion filled inside the lumen. The calcium alginate film of the present invention has a glossy appearance as if it is covered with a layer of water even after thawing, and is rich in water. Therefore, it is elastic and has a unique texture in which the film is easily torn when it is contained in the mouth and the inclusions spread in the mouth. In addition, due to the flexibility of the film, the spherical food exhibits a flat spherical shape due to its own weight when served on a plate or the like. From such a texture and appearance, the spherical food of the present invention can be used as a raw egg yolk-like food described later, a seasoning and a dessert that can enjoy an eye-catching appearance and texture.

<Patagium>
The film of the present invention is a thin film containing calcium alginate and a predetermined thickening polysaccharide and formed on the outer edge of the inclusion. The thickness of the film is not particularly limited, but may be, for example, 50 μm to 3 mm, and more preferably 80 μm to 2 mm.

<Calcium alginate>
The calcium alginate of the present invention is the main component of the above-mentioned film and is formed by a contact reaction between an alkali metal alginate and calcium ions. Calcium alginate has a three-dimensional network structure and has water retention.
Calcium alginate is not included in the thickening polysaccharide of the present invention.

<Thickening polysaccharide>
The thickening polysaccharide of the present invention refers to a thickening polysaccharide contained in a film, but is neither modified starch alone, crosslinked starch alone, or modified starch or crosslinked starch only. Furthermore, the thickening polysaccharide of the present invention may contain modified starch and crosslinked starch as long as it contains other thickening polysaccharides, as long as the effects of the present invention are not impaired. The thickening polysaccharide of the present invention can stably develop a glossy luster that is covered with a layer of water even after thawing on the calcium alginate film.
As the thickening polysaccharide of the present invention, one or more of the following can be used under the condition that "only modified starch, only crosslinked starch, and only unmodified starch and crosslinked starch are excluded".
For example, examples of the thickening polysaccharide include starch, gum, pectin, curdlan, pullulan, and mannan.
Examples of starch include unprocessed starch and modified starch obtained by processing unprocessed starch. Specific examples of starch will be described later.
Examples of the gum quality include xanthan gum, gellan gum, carrageenan, locust bean gum, tara gum, guar gum, gum arabic, tamarind gum, silium seed gum and the like.

<Thickening polysaccharide / Modified starch>
The modified starch of the present invention refers to starch purified from raw materials such as potato, corn, tapioca, wheat, and rice, excluding the following modified starch. Specific examples of the unmodified starch include rice starch, corn starch, tapioca starch, potato starch, wheat starch and the like.
Here, the present inventors have obtained the finding that when unmodified starch is used alone or in combination with crosslinked starch as the thickening polysaccharide added to the above-mentioned film, a glossy appearance cannot be obtained. Therefore, in the thickening polysaccharide of the present invention, the embodiment in which the unmodified starch is used alone or in combination with the crosslinked starch is excluded.

<Thickening polysaccharide / Modified starch>
The modified starch of the present invention refers to unmodified starch that has been physically, enzymatically, and chemically processed. Specific examples of the processed starch include hydroxypropyl starch, acetylated oxidized starch, sodium octenyl succinate starch, acetate starch, oxidized starch, hydroxypropylated phosphoric acid cross-linked starch, phosphorylated starch and the like.

<Thickening polysaccharide / cross-linked starch>
The crosslinked starch of the present invention is a kind of modified starch, and refers to unprocessed starch that has been subjected to a treatment for cross-linking between a plurality of hydroxyl groups. Specific examples of the crosslinked starch of the present invention include acetylated adipic acid crosslinked starch, acetylated phosphoric acid crosslinked starch, phosphoric acid crosslinked starch, and phosphoric acid monoesterified phosphoric acid crosslinked starch.
Crosslinked starch is commonly known as a thickening polysaccharide that enhances stability and water retention. However, the present inventors have obtained a surprising finding that when crosslinked starch is used alone or in combination with modified starch in the calcium alginate film, a glossy appearance cannot be obtained. Therefore, in the thickening polysaccharide of the present invention, the mode in which the crosslinked starch is used alone or in combination with the unmodified starch is excluded.

<Thickening polysaccharide / Hydroxypropyl starch>
The thickening polysaccharide of the present invention may be, for example, hydroxypropyl starch. Hydroxypropyl starch is a modified starch in which a hydroxypropyl group is added to the unprocessed starch. In the film of the present invention, by using hydroxypropyl starch as the thickening polysaccharide, it is possible to stably express the gloss of a particularly large mass with respect to the calcium alginate film.

<Film / Other components>
In addition to calcium alginate and the thickening polysaccharide, the film in the present invention may contain other components as long as the effects of the present invention are not impaired. Examples of the other component include polyvalent metal salts other than the calcium salt of alginic acid, such as magnesium salt and aluminum salt.

<Inclusives>
The inclusions of the present invention refer to raw materials for frozen spherical foods contained by the above-mentioned film. The inclusions of the present invention may be, for example, a liquid or sol-like substance having fluidity. As a result, it is possible to give a peculiar texture that the inclusions flow out when the film is broken when it is contained in the mouth.
The components of the inclusions may be selected according to the use of the frozen spherical food. For example, when the spherical food is a raw egg yolk-like food, the inclusion may be an egg yolk-like liquid. Further, in the case of a seasoning, it is preferable that a known seasoning is included as an inclusion, and examples thereof include dressings and mayonnaise. In addition, by using a paste of vegetables and fruits as an inclusion, a substantially spherical jelly-like dessert can be produced.

<Viscosity of inclusions>
The viscosity of the inclusions is preferably 500 mPa · s or more and 30,000 or less mPa · s, 1000 mPa · s or more and 20000 mPa · s or less, and further 1500 mPa · s or more and 15000 mPa · s or less at 20 ° C. ..
By setting the viscosity of the inclusions in the above range, the inclusions can be easily encapsulated in the film in the manufacturing method described later. Further, by setting the viscosity to 1000 mPa · s or more and 20000 mPa · s or less, particularly 1000 mPa · s or more and 20000 mPa · s or less, it is good that the inclusions flow out when the film is broken by containing spherical food in the mouth. Can give a nice texture.

<Specificity of inclusions>
The specific gravity of the inclusions is preferably 1.02 to 1.30, 1.04 to 1.20, and further 1.05 to 1.15 at 20 ° C. By setting the specific gravity of the inclusions in such a range, the inclusions can be easily included in the film in the manufacturing method described later.
The specific gravity of the inclusions can be measured, for example, as follows. First, the egg white processing liquid is filled in a container having a known weight and capacity. At this time, the inclusions are filled so as not to spill from the container due to surface tension, and the amount overflowing from the container is scraped off. Subsequently, the weight of the container filled with the inclusions is measured, and the weight of the inclusions is obtained by subtracting the weight of the container from the weight. Further, the specific gravity can be obtained by dividing the weight of the inclusions by the weight of water (capacity of the container). The temperature of the inclusions at the time of measuring the specific gravity can be 20 to 40 ° C., for example, 20 ° C.

<Raw egg yolk-like food>
The frozen spherical food of the present invention may be a food obtained by freezing a raw egg yolk-like food.
The raw egg yolk-like food of the present invention refers to a spherical food containing an egg yolk-like liquid as an inclusion, as described above, and refers to a spherical food that imitates a raw egg yolk that is still wrapped in an egg yolk membrane such as a chicken egg. The egg yolk-like liquid is a liquid material having a viscosity and color tone similar to that of raw liquid egg yolk, which imitates raw liquid egg yolk. The egg yolk-like liquid may contain an appropriate amount of fresh liquid egg yolk.
The raw egg yolk-like food of the present invention can be preferably used as a substitute for raw egg yolk because the film has the same elasticity and breaking stress as the egg yolk film. Further, according to the present invention, since a glossy and glossy appearance can be maintained even after thawing, it is possible to provide a more easy-to-use raw egg yolk-like food as a frozen food with improved distribution and storage stability. Can be done.

<Appearance of frozen spherical food>
The frozen spherical food of the present invention is characterized by having a large glossy mass. That is, in the frozen spherical food of the present invention, in order to move the frozen spherical food to room temperature (25 ° C.) and prevent drying, at least the upper surface of the frozen spherical food is covered with a packaging film such as a nylon pouch or a wrap. Let stand for 3 hours to thaw. At this time, the spherical food and the packaging film may be in contact with each other or may not be in contact with each other. Further, the state of the packaging film covering the spherical food may be a sealed state or an unsealed state. After thawing, the entire surface of the frozen spherical food placed on a flat plate is partitioned, and each of the plurality of images taken with a digital microscope is subjected to the "shape" described later under predetermined analysis conditions using a visual analyzer. Among the glossy lumps calculated by performing the "information" process, the number of pixels of the largest glossy lump is equal to or greater than a predetermined value.

<Digital microscope>
The digital microscope used in the imaging of the present invention refers to a digital imaging device having an imaging lens provided with a light source (illumination) and an imaging element, which can magnify an object and perform imaging under the following imaging conditions.
In the present invention, the frozen spherical food after thawing is placed on a flat plate (sample table) using the above digital microscope, and an image of the entire surface of the spherical food is taken from above in the vertical direction of the flat plate. Specifically, a plurality of images are taken by partitioning the entire surface of the film when the frozen spherical food after thawing is viewed from above. It is preferable that the imaging regions do not overlap in each image, but a part of the imaging region may overlap. As a result, the gloss of the entire surface of the film of the frozen spherical food can be appropriately imaged. The size of each image is a size that can capture an area of 12 mm × 16 mm based on the following lens and magnification.

<Imaging conditions (1)>
In the present invention, the following imaging condition (1) is used in order to appropriately image the gloss using the digital microscope. The imaging condition (1) is as follows.
(1-1) Lens used: Ultra-compact high-performance zoom lens (magnification 20-200) Model number VH-Z20R (manufactured by KEYENCE CORPORATION)
(1-2) Magnification of the above lens: 20 times (1-3) Shutter speed: 1/120 sec
(1-4) Gain: 6db
(1-5) White balance: 2700K
As a result, the image size used for the analysis can be defined, and an image with an image quality suitable for the analysis of the glossy mass can be captured.

<Visual Analyzer>
The visual analyzer used in the present invention is an image capable of defining the size of a glossy mass by performing an analysis process on the image of the film surface captured by the digital microscope under the following analysis condition (2). It is a processing device. The visual analyzer used in the present invention is "IRIS" manufactured by Alpha Moss Japan Co., Ltd.

<Analysis condition (2)>
The analysis condition (2) of the present invention is as follows.
(2-1) Color space used for analysis: HSV color space (2-2) Numerical range of gloss in HSV color space ・ H (hue): 0 to 180 (maximum selectable numerical range: 0 to 180)
-S (vividness): 0 to 65 (maximum selectable numerical range: 0 to 255)
-V (brightness): 110-255 (maximum selectable numerical range: 0-255)
(2-3) In the pixels extracted as the gloss, the shortest distance between each pixel and other pixels for being excluded from the gloss mass: 1 pixel or more The analysis condition (2-2) is calcium alginate. Defines a range of colors suitable for the gloss peculiar to the film.
The analysis condition (2-3) defines the condition to be extracted as a glossy mass. The detailed extraction processing method will be described below.

<Analysis processing by visual analyzer>
In the visual analyzer, each image is automatically analyzed by performing "Shape Descriptors" processing under the above analysis condition (2).
The “shape information” refers to information regarding the shape of a glossy mass extracted from each image by the visual analyzer assuming that the analysis condition (2-3) is satisfied.
The "shape information" process is a process of extracting glossy lumps of each image in the visual analyzer and automatically calculating the number of pixels of each of the extracted glossy lumps. Specifically, an input operation is performed so that the "shape information" is displayed on the visual analyzer. As a result, the "shape information" data of each sample is displayed on a display or the like connected to the visual analyzer, and the calculated number of pixels of the glossy mass is displayed as an "Area".
More specifically, the visual analyzer performs the following processing:
First, pixels satisfying the above analysis condition (2-2) in the image are extracted as "glossy pixels".
Subsequently, among the glossy pixels extracted as the glossy, the range satisfying the analysis condition (2-3) is extracted as a glossy mass. Specifically, it is determined whether or not each gloss pixel is adjacent to another gloss pixel in any of vertical, horizontal, and diagonal directions. A gloss pixel determined to be adjacent to another gloss pixel is determined to be part of a gloss mass. On the other hand, glossy pixels that are not adjacent to other glossy pixels, that is, that are determined to be one or more pixels away from other glossy pixels, are excluded from the glossy mass.
Then, the number of pixels of each extracted glossy mass is calculated.
In the frozen spherical food of the present invention, when it has a moist and desired appearance, the pixels extracted as gloss are densely extracted and extracted in a large mass. On the other hand, in the case of a spherical food having a dry surface or not having a desired appearance, these pixels are scattered or the density is low, and the area is larger than the number of pixels described later. Is not extracted.

<Maximum number of pixels of glossy mass on the surface of the film>
The maximum number of pixels of the glossy mass on the surface of the film of the present invention means the largest number of pixels of the glossy mass extracted from each image of one spherical food under the above analysis conditions. .. The maximum number of pixels is 20,000 pixels or more, preferably 30,000 pixels or more, and even more preferably 32,000 pixels or more. By defining the glossy mass in this way in the frozen spherical food of the following size, it is possible to provide the frozen spherical food having a moist and glossy luster.

<Size of frozen spherical food>
The size of the frozen spherical food of the present invention is defined by the projected area of the frozen spherical food placed on the flat plate projected onto a projection plane substantially parallel to the flat plate. The projected area is 144 mm ² or more, and more preferably 400 mm ² or more. For example, the projected area is preferably 2500 mm ² or less. Examples of the frozen spherical food having such a size include the above-mentioned raw egg yolk-like food. As a method of calculating the projected area, for example, a frozen spherical food can be imaged with a digital microscope or another imaging device, and the frozen spherical food can be measured by using the automatic area measurement function.

<Manufacturing method of frozen spherical food>
The method for producing a frozen spherical food of the present invention is a method for producing a frozen spherical food having a film covering inclusions.
The method for producing a frozen spherical food of the present invention includes a step of preparing an aqueous solution containing an alkali metal alginate and a thickening polysaccharide (excluding modified starch only, cross-linked starch only, and unmodified starch and cross-linked starch only). , A step of immersing a hemispherical cup filled with an inclusion-forming filler in the above-mentioned film-forming aqueous solution, and a step of forming a film containing calcium alginate and a thickening polysaccharide on the surface of the inclusion solution. ..

<Preparation process>
First, a film-forming aqueous solution containing an alkali metal alginate and a thickening polysaccharide (excluding modified starch only, crosslinked starch only, and unmodified starch and crosslinked starch only) is prepared.
The alkali metal alginate used in the present invention refers to salts of alginic acid which are abundantly contained in brown algae as polysaccharides, and refers to, for example, sodium alginate, potassium alginate and the like.
As the thickening polysaccharide used in this step, the above-mentioned ones can be used.

<Content of thickening polysaccharide in aqueous solution for film formation>
The content of the thickening polysaccharide in the aqueous solution for forming a film of the present invention is preferably 0.5% or more, 1% or more, and further 2% or more. Thereby, the above-mentioned preferable luster can be stably expressed. Further, there is no particular upper limit on the content of the thickening polysaccharide, but for example, it is preferably 15% or less, and is preferably 10% or less. As a result, it is possible to develop gloss on the film while suppressing the cost of raw materials.

<Immersion process>
Next, the hemispherical cup filled with the inclusion-forming filler is immersed in the film-forming aqueous solution. By this step, the alkali metal alginate in the aqueous solution for forming a film comes into contact with calcium ions, and a film is formed as described later.
In this step, for example, even if the bottom of the hemispherical cup is filled with a small amount of the film-forming aqueous solution, the filling is filled on the aqueous solution, and then the hemispherical cup is immersed in the film-forming aqueous solution. good. Alternatively, the filling may be filled in a hemispherical cup immersed in a film-forming aqueous solution. Filling can be performed by a conventional method using a filling machine capable of automatically filling a predetermined amount of filling, a syringe, or the like.

<Filling for inclusion formation>
The inclusion-forming filler of the present invention refers to a liquid or gel-like substance that can be an inclusion that is coated on the film of the frozen spherical food and contains calcium ions. The filler for forming inclusions is also hereinafter simply referred to as “filler”. The inclusion forming filler can supply calcium ions for forming a film in the dipping step and the film forming step.
The inclusion-forming filler may contain a water-soluble calcium salt as calcium ions. The water-soluble calcium salt is not particularly limited as long as it is a calcium salt having the property of being soluble in edible water, and examples thereof include calcium chloride, calcium lactate, calcium gluconate, and hydrates of these compounds. ..
The calcium ion concentration of the inclusion-forming filler may be adjusted so that the film has appropriate flexibility, for example, 0.1 to 1.7%, and further 0.3 to 1. It should be 5%.
Further, the viscosity and specific gravity of the inclusion-forming filler may be adjusted from the viewpoint of ease of molding and the like.

<Viscosity of filler for forming inclusions>
The viscosity of the inclusion forming filler is preferably 500 mPa · s or more and 30,000 or less mPa · s, 1000 mPa · s or more and 20000 mPa · s or less, and further 1500 mPa · s or more and 15000 mPa · s or less at 20 ° C. It is good to be.
By setting the viscosity of the packing for forming inclusions within the above range, molding of the film becomes easy. Further, by setting the viscosity to 1000 mPa · s or more and 20000 mPa · s or less, particularly 1000 mPa · s or more and 20000 mPa · s or less, the texture of the spherical food can be improved as described above.
The viscosity of the inclusion-forming filler can be adjusted by adjusting the blending amount of the raw material of the inclusion-forming filler, the type and amount of the thickener, and the like.

<Specific gravity of filler for forming inclusions>
The specific gravity of the inclusion forming filler is preferably 1.02 to 1.30, 1.04 to 1.20, and further 1.05 to 1.15 at 20 ° C. .. By setting the specific gravity of the inclusion forming filler in such a range, molding of the film becomes easy.
The specific gravity of the inclusion-forming filler can be measured, for example, at 20 ° C. in the same manner as the inclusions described above.
For adjusting the specific density, for example, sugars such as starch syrup, sucrose, trehalose, dextrin, and reduced dextrin are used.

<Hemispherical cup>
The hemispherical cup of the present invention is a cup having a recessed hemispherically recessed portion. By using a hemispherical cup, a spherical food of the above size can be molded. The shape and material thereof are not particularly limited, but for example, those made of resin or stainless steel are used. Further, the hemispherical cup may have a continuously formed curved surface. Alternatively, depending on the filling and dipping method in the dipping step, one or more and 100 or less small holes may be formed on the bottom surface and the side wall surface. The size of the hemispherically recessed recess of the hemispherical cup can be determined according to the size of the frozen spherical food to be produced.

<Film formation process>
Next, by holding the hemispherical cup in the film-forming aqueous solution, a film containing calcium alginate and the thickening polysaccharide is formed on the surface of the filling.
More specifically, when the alkali metal alginate in the film-forming aqueous solution and the calcium ion of the filler come into contact with each other, the two carboxyl group molecules of the alkali metal alginate are cross-linked via the calcium ion to generate calcium alginate. .. As a result, a film containing calcium alginate as a main component is formed.
The holding time of the hemispherical cup in the aqueous solution for forming a film is preferably such that a film having an appropriate thickness is formed, for example, about 1 to 10 minutes.
Further, the holding method is not limited, and for example, the hemispherical cup may be shaken in an aqueous solution for forming a film. As a result, the reaction between the film-forming aqueous solution and the filling material is promoted, and it becomes easy to mold into a spherical shape.
By this film forming step, a spherical food in which a film containing calcium alginate and the thickening polysaccharide covers the inclusions can be obtained.

<Freezing process>
By freezing the above spherical food, a frozen spherical food can be obtained.
The freezing treatment in this step is performed, for example, by freezing a spherical food filled and sealed in a packaging bag or container in a freezer or a freezing room at −15 ° C. to −40 ° C. or lower. The time required for the freezing process is not particularly limited. The frozen spherical food after the freezing treatment is stored in a freezer or a freezing room at −30 ° C. or lower, for example.

<Action and effect of the present invention>
The frozen spherical food of the present invention has a calcium alginate film containing a predetermined thickening polysaccharide, so that a large mass of gloss can be imaged and has a glossy luster as if covered with a layer of water. ..
Conventionally, spherical foods having a film containing calcium alginate have been known as raw egg yolk-like foods and fish egg-like foods. Such spherical foods have a glossy, elastic and water-retaining film that easily breaks when placed in the mouth and the inclusions spread in the mouth, which is a unique food similar to raw egg yolk or roe. Have a feeling.
Here, in order to evoke a peculiar elastic texture from the calcium alginate film, it is preferable to have a moist and glossy texture as if a water film is stretched on the surface of the film. Therefore, the present inventors have diligently studied a frozen spherical food that can stably express such a unique texture even after freezing and thawing, and have come up with the idea of adding a predetermined thickening polysaccharide to the calcium alginate film.
As shown in the following examples, as the thickening polysaccharide of the present invention, the modified starch and the crosslinked starch do not give a desired glossy appearance when used alone or when used alone. .. In particular, when crosslinked starch is used alone, the gloss on the film surface is lost. On the other hand, in the film, when hydroxypropyl starch is used among the modified starches, a particularly glossy and glossy appearance can be obtained.
Both modified starch and crosslinked starch are widely used thickening polysaccharides, and crosslinked starch is particularly known to have high water retention and stability. Therefore, the fact that these do not exert sufficient effects is a surprising result in view of the conventional common general knowledge, and it can be considered that a phenomenon peculiar to the calcium alginate film has occurred. That is, the thickening polysaccharide contained in the film of the present invention enhances the water retention function of the surface by a mechanism peculiar to the film by some interaction with calcium alginate forming a three-dimensional network structure, and freezes and freezes. It is considered that a supple and moisturized appearance can be stably obtained after thawing.
In particular, when the size is about the size of raw egg yolk, which is larger than that of fish eggs, the texture of the surface of each spherical food becomes conspicuous. According to the present invention, even in a large spherical food having a film containing calcium alginate and having a size similar to that of raw egg yolk, it has a moist and glossy luster, and has a good appearance that gives a fresh impression and evokes a favorable texture. Can be realized. Therefore, according to the present invention, the possibilities of the spherical food can be expanded to include not only raw egg yolk-like foods but also seasonings, desserts and the like having a spherical and eye-catching appearance and a unique texture.

Hereinafter, the present invention will be further described based on examples and the like. The present invention is not limited to these.

[Example 1]
In Example 1, a frozen egg yolk-like processed product was produced as the frozen spherical food of the present invention.

(Preparation of filling for inclusion formation)
First, an egg yolk-like liquid was produced as a filling material for forming inclusions in a frozen egg yolk-like processed product. According to the formulation table below, the raw materials for the egg yolk-like liquid were blended and stirred with a mixer until uniform. After stirring, the mixture was heated to 90 ° C., degassed, and then cooled to 5 to 10 ° C. to obtain an egg yolk-like liquid. The obtained egg yolk-like liquid was refrigerated until use.

(Combining egg yolk-like liquid)
Egg yolk 10%
Syrup 10%
Dextrin 10%
Calcium lactate 1%
Modified starch 5%
Thickening polysaccharide 1%
Shimizu Residual ――――――――――――――――――――――
Total 100.0%

(Measurement of viscosity and specific gravity of egg yolk-like liquid)
The viscosity of the egg yolk-like liquid was measured by a BH type viscometer (manufactured by Toki Sangyo Co., Ltd.) at a product temperature of 20 ° C., a rotation speed of 10 rpm, and a rotor No. It was measured under the condition of 4. The viscosity of the egg yolk-like liquid was 12000 mPa · s.
In addition, the specific gravity of each egg yolk-like liquid was measured by the following method. First, each egg yolk-like liquid was filled in a plastic cup (capacity 230 ml). At this time, each egg yolk-like liquid was filled so as not to spill from the cup due to surface tension, and the amount overflowing from the cup was scraped off. Subsequently, the weight of each egg yolk-like liquid filled in the cup was measured, and the weight was divided by the weight of water (230 g) to obtain the specific gravity. The specific gravity of the egg yolk-like liquid was 1.10 at 20 ° C.

(Adjustment of alginic acid aqueous solution)
Next, an alginic acid aqueous solution was prepared as a film-forming aqueous solution. According to the formulation table below, an aqueous alginic acid solution was blended and stirred with a mixer until uniform. After stirring, it was stored in a refrigerator.
(Combining alginic acid aqueous solution)
Na alginate 1%
Hydroxypropyl starch derived from tapioca 10%
Shimizu Residual ――――――――――――――――――――――――――――――――――――――
100% in total

(Manufacturing of frozen processed egg yolk-like products)
Subsequently, a hemispherical cup filled with the prepared egg yolk-like liquid was immersed in an aqueous alginic acid solution. Specifically, after injecting a small amount of alginic acid aqueous solution into the bottom of the hemispherical cup, 10 g of egg yolk-like liquid was filled on the alginic acid aqueous solution in the hemispherical cup. The hemispherical cup was formed of a continuous curved surface without small holes, and a cup having a major axis of 50 mm, a minor axis of 30 mm, and a depth of 30 mm was used. A hemispherical cup filled with egg yolk-like liquid was immersed in an aqueous alginic acid solution. The holding time of the hemispherical cup in the aqueous solution was 4 to 5 minutes. Then, the hemispherical cup was pulled up from the alginic acid aqueous solution, the yolk-like processed product was taken out from the hemispherical cup, and washed with water. This was filled in a packaging bag, sealed, and then frozen at −30 ° C. or lower.

[Examples 2 to 7 and Comparative Examples 1 to 6]
In Examples 2 to 7 and Comparative Examples 1 to 6, a frozen egg yolk-like processed product was produced in the same manner as in Example 1 except that the types of thickening polysaccharides and their blending ratios were shown in Table 1.

[Example 8]
In Example 8, as the frozen spherical food of the present invention, a frozen spherical food containing a blueberry sauce was produced.

(Preparation of blueberry sauce)
First, a blueberry sauce was prepared as a filling material for forming inclusions in Example 8. According to the formula below, the ingredients for the blueberry sauce were blended and mixed with a mixer until uniform. After stirring, the mixture was degassed to obtain a blueberry sauce. The resulting blueberry sauce was refrigerated until use.

(Mixed with blueberry sauce)
Commercial blueberry sauce 90%
Calcium lactate 1%
Syrup 9%
―――――――――――――――――――――――
100% in total

(Measurement of viscosity and specific density of blueberry sauce)
The viscosity and specific density of the blueberry sauce were measured in the same manner as the measurement of the viscosity and specific density of the egg yolk-like liquid.
The viscosity (20 ° C.) of the blueberry sauce was 1590 mPa · s.
The specific gravity of the blueberry sauce was 1.10 at 20 ° C.

(Making frozen spherical food with blueberry sauce)
In Example 8, a frozen spherical food was produced in the same manner as in Example 1 except that the filling was a blueberry sauce.

[Confirmation of moldability]
In order to confirm the moldability of the prepared frozen spherical foods (hereinafter, also referred to as samples) of Examples 1 to 9, the shape of the prepared frozen spherical food after being taken out from the hemispherical cup before the freezing treatment was visually confirmed.
In each of the spherical foods, the film could be molded into a substantially spherical shape with a smooth surface. From this, the viscosity of the packing (inclusion) is within the range of 500 mPa · s or more and 30,000 mPa · s or less (for example, 1590 mPa · s (Example 8), 12000 mPa · s (Examples 1 to 7)), and the specific gravity. It was confirmed that by setting the value to 1.02 or more and 1.30 or less (for example, 1.10), it is possible to mold into a beautiful substantially spherical shape.

[Thawing frozen spherical food and checking size]
Subsequently, the samples of Examples 1 to 8 and Comparative Examples 1 to 6 were thawed and allowed to stand on a flat plate to confirm the size.
Specifically, first, each sample frozen at -30 ° C is moved to room temperature (25 ° C) together with the packaging bag, left to stand for 3 hours with the mouth of the bag open, thawed, and then taken out of the bag and flat plate. It was left on top. The surface of each static sample was imaged from above in the vertical direction of a flat plate using a digital microscope (“VHX-20000”, manufactured by KEYENCE CORPORATION). As the lens, an ultra-compact high-performance zoom lens (magnification 20 to 200) "VH-Z20R" (manufactured by KEYENCE CORPORATION) was used. Then, the size (projected area) of each sample was calculated using the automatic area measurement function.
As a result, in each sample, the planar shape was a substantially elliptical sphere having a minor axis of about 30 mm and a major axis of about 30 mm, and the projected area was about 900 mm ² .

[Evaluation of gloss on the film surface after thawing of frozen spherical food]
(Image of frozen spherical food)
Subsequently, the gloss on the surface of the coatings of the samples of Examples 1 to 8 and Comparative Examples 1 to 6 which were allowed to stand on a flat plate after thawing was analyzed and evaluated.
Specifically, first, the entire surface of the frozen spherical food thawed as described above and placed on a flat plate was imaged using the above digital microscope. The following conditions were used for imaging. That is, the magnification was 20 × 20 (400 times), the shutter speed was 1/120 sec, the gain was 6db, and the white balance was 2700K. As an imaging lens, an ultra-compact high-performance zoom lens model number VH-Z20R (manufactured by KEYENCE CORPORATION) was used. The image pickup lens includes a light source arranged in a ring around the image pickup lens, and the light source is a halogen lamp of 12 V and 100 W, which moves as the image pickup lens moves up and down.
The frozen spherical food placed on the flat plate was imaged from above in the vertical direction of the flat plate under the above imaging conditions. At this time, the surface of each sample was imaged in each section of 12 mm × 16 mm, and about 6 images were obtained for each sample.

(Analysis of the maximum value of glossy mass)
Subsequently, in order to evaluate the size of the glossy mass with respect to the captured image, analysis was performed using a visual analyzer (“IRIS”, manufactured by Alpha Moss Japan Co., Ltd.).
Specifically, first, the threshold values of the colors to be extracted were set to 0 to 180 for H (hue), 0 to 65 for S (vividness), and 110 to 255 for V (brightness) in the HSV color space. Then, by performing an input operation so as to display "shape information" on the visual analyzer, "shape information" processing was performed, and the number of pixels for each block was calculated.
Then, among the number of pixels of the glossy mass output for the image obtained by capturing each sample, the largest one is defined as the "maximum value of the glossy mass" of the sample. The results are shown in Table 1.

(Evaluation criteria)
Based on the analysis results of the maximum value of the above glossy mass, the gloss of each sample was evaluated based on the following evaluation criteria. Table 1 shows the results of each sample.
(Evaluation criteria)
A: It has a very large glossy mass of 32000 pixels or more and has a very clean, glossy and good appearance.
B: It has a large glossy mass of 30,000 pixels or more and less than 32,000 pixels, and has a good appearance with a clean gloss.
C: It has a slightly large glossy mass of 20000 pixels or more and less than 30,000 pixels, and has a glossy appearance.
D: The glossy mass is less than 20000 pixels, and the glossy mass is small or hardly seen, giving an impression of dullness.

(Analysis result of glossy mass)
As shown in Table 1, in Examples 1 to 8, the maximum value of the glossy mass (hereinafter, also simply referred to as “glossy mass”) was 20000 pixels or more, and the surface of the film was glossy even after freezing and thawing.
Specifically, as shown in Table 1, the glossy mass of Comparative Example 2 in which the alginic acid aqueous solution did not contain the thickening polysaccharide was 18120 pixels, whereas the glossy mass of Examples 1 to 8 was more than that. It was large, over 20000 pixels. The glossy mass of the examples was 26657 pixels (Example 7) or more and 41459 pixels (Example 1) or less. As described above, it was confirmed that the size of the glossy mass was increased by using the predetermined thickening polysaccharide, and the surface of the film had a glossy and fresh appearance even in the image taken with a microscope.
In particular, in Examples 1 to 6 and 8 using hydroxypropyl starch, it was confirmed that the lumps of offal were 30,000 pixels or more, and that the actual image had a very glossy and glossy appearance.
In addition, when the amount of thickening polysaccharide in the alginic acid aqueous solution was large, the size of the glossy mass tended to increase.
On the other hand, even if the alginic acid aqueous solution is a sample containing a thickening polysaccharide, Comparative Example 1 using modified starch has only 5077 pixels of glossy lumps, and even in an actual image, the surface is dry and fine irregularities are formed. It was confirmed that it was in a rough state. Similarly, in Comparative Examples 3 to 6 using the crosslinked starch, the lumps of the offal were 150 pixels or less. Therefore, the surfaces of these films were visually confirmed to be very rough and had almost no gloss. As described above, it was confirmed that when only modified starch was used as the thickening polysaccharide in the alginic acid aqueous solution or when only crosslinked starch was used, the desired luster could not be imparted to the film. Further, although not shown in Table 1, when only two types of thickening polysaccharides, modified starch and crosslinked starch, are used in the alginic acid aqueous solution, the glossy mass is similarly 150 pixels or less, which is desired for the film. It was confirmed that gloss could not be imparted.

[summary]
As described above, all of the obtained frozen spherical foods had a substantially spherical shape, and had a glossy appearance with a moist texture as if the surface was covered with a layer of water.
Further, in the samples of Comparative Examples 1 to 6, the size of the glossy mass was small and the surface was confirmed to be rough, whereas in Examples 1 to 8, the size of the glossy mass was large and good. there were.
In particular, with respect to Examples 1 to 6 and 8 in which hydroxypropyl starch was used, the lumps of offal were of sufficient size and had a good glossy appearance with the above-mentioned preferable texture.
Further, in Example 7 using xanthan gum, which is a gum, the size of the glossy mass was slightly smaller than that in the other examples, but it had an appearance giving a glossy and moist impression.
In addition, from the results of Example 8, according to the present invention, a frozen spherical food having the same size as the raw egg yolk-like food and having a glossy appearance with the above-mentioned preferable texture is produced regardless of the inclusions. It was confirmed that it could be done. As a result, it was confirmed that the frozen spherical food of the present invention can be used as a seasoning to be added to desserts and other foods by devising the inclusions.

Claims (2)

A frozen spherical food having a film that covers the inclusions.
The film contains calcium alginate and modified starch and / or gum (excluding the film containing only crosslinked starch as the modified starch).
After moving the frozen spherical food to room temperature (25 ° C.) and allowing it to stand for 3 hours to thaw, the frozen spherical food is allowed to stand on a flat plate to perform imaging satisfying the following (1-1) to (1-5). Under the condition (1), the following analysis conditions (2-1) to (2-3) (2) are used from each of the plurality of images taken by partitioning the entire surface of the film with a digital microscope using a visual analyzer. The number of pixels of the largest glossy mass among the glossy masses extracted in) is 20000 pixels or more.
^{A frozen spherical food having an area of 144 mm 2} or more projected on a projection plane substantially parallel to the flat plate.
[Imaging conditions (1)]
(1-1) Lens used: Ultra-compact high-performance zoom lens (magnification 20-200) Model number VH-Z20R (manufactured by KEYENCE CORPORATION)
(1-2) Magnification of the lens: 20 times (1-3) Shutter speed: 1/120 sec
(1-4) Gain: 6db
(1-5) White balance: 2700K
[Analysis condition (2)]
(2-1) Color space used for analysis: HSV color space (2-2) Numerical range of gloss in HSV color space ・ H (hue): 0 to 180 (maximum selectable numerical range: 0 to 180)
-S (vividness): 0 to 65 (maximum selectable numerical range: 0 to 255)
-V (brightness): 110-255 (maximum selectable numerical range: 0-255)
(2-3) In the pixels extracted as the gloss, the shortest distance between each pixel and other pixels for being excluded from the gloss mass: 1 pixel or more. A method for producing a frozen spherical food having a film covering the inclusions.
A step of preparing a film-forming aqueous solution containing an alkali metal alginate and modified starch and / or gum (however, the film-forming aqueous solution containing only modified starch as the modified starch is excluded).
A step of immersing a hemispherical cup filled with a filling material for forming inclusions containing calcium ions in the aqueous solution for forming a film, and a step of immersing the hemispherical cup.
A step of forming the film containing calcium alginate and the thickening polysaccharide on the surface of the inclusion-forming filler by holding the hemispherical cup in the film-forming aqueous solution.
Including
After moving the frozen spherical food to room temperature (25 ° C.) and allowing it to stand for 3 hours to thaw, the frozen spherical food is allowed to stand on a flat plate to perform imaging satisfying the following (1-1) to (1-5). Under the condition (1), the following analysis conditions (2-1) to (2-3) (2) are used from each of the plurality of images taken by partitioning the entire surface of the film with a digital microscope using a visual analyzer. The number of pixels of the largest glossy mass among the glossy masses extracted in) is 20000 pixels or more.
A method for producing a frozen spherical food having an ^{area of 144 mm 2} or more projected on a projection plane substantially parallel to the flat plate.
[Imaging conditions (1)]
(1-1) Lens used: Ultra-compact high-performance zoom lens (magnification 20-200) Model number VH-Z20R (manufactured by KEYENCE CORPORATION)
(1-2) Magnification of the lens: 20 times (1-3) Shutter speed: 1/120 sec
(1-4) Gain: 6db
(1-5) White balance: 2700K
[Analysis condition (2)]
(2-1) Color space used for analysis: HSV color space (2-2) Numerical range of gloss in HSV color space ・ H (hue): 0 to 180 (maximum selectable numerical range: 0 to 180)
-S (vividness): 0 to 65 (maximum selectable numerical range: 0 to 255)
-V (brightness): 110-255 (maximum selectable numerical range: 0-255)
(2-3) In the pixels extracted as the gloss, the shortest distance between each pixel and other pixels for being excluded from the gloss mass: 1 pixel or more.