JP2020046350A - Method for catching sign of bloom generation at early stage - Google Patents

Abstract

To provide a method capable of predicting whether or not bloom of a fat composition, especially oily food can be generated more quickly and at an earlier stage on the basis of an observation method for a surface fine structure in a fat composition of which fat is a continuous phase.SOLUTION: Disclosed is a method for catching a sign of bloom generation using at least one change of a surface structure B or a surface structure B' of the surface microstructure as an index in a fat composition whose fat is a continuous phase. The surface structure B refers to a fat crystal convex structure which is generated more upward than the reference surface and whose height is low and breadth is wide, and the surface structure B' refers to a concave structure engraved more downward than the reference surface around the surface structure B, respectively.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a method for observing a surface microstructure in a fat or oil composition in which the fat or oil is a continuous phase.

Chocolate research has a long history, and Bloom has been considered a number of issues in the past as its greatest concern. Bloom is a phenomenon in which fats and oils present on the surface of chocolate for some reason crystallize and whiten.
Bloom is evaluated as inferior in chocolate, so that it does not generally occur during storage or is one of the important items in quality evaluation.
As a general method, visual evaluation is used, but there is a concern that errors may occur due to the experience of the evaluator.

When observing the occurrence of bloom over time and comparing it with past studies, comparison is often made using photographs, but it is necessary to photograph the surface of chocolate under the same conditions such as light amount, reflection, color tone etc. There are technical difficulties. In addition, a certain period of time is required until the stage of visual evaluation, and the storage test is inevitably long, so sometimes an accelerated test (cycle test) that changes the temperature is performed for the purpose of catching the change quickly. is there.
On the other hand, in the case of product development, CBE (Cocoa Butter Equivalent: rich in 1,3- and 2-unsaturated symmetric triacylglycerols and can be mixed with cocoa butter at any ratio) and CBR (Cocoa Butter Equivalent) Replacer: Additive mainly composed of fats and oils such as laurin-based hard butter with low compatibility with cocoa butter, CBS (cocoa butter substitute: high elaidic acid type and low trans non-laurin type hard butter), and emulsifiers. When looking at the effect of, as the types increase, it becomes more difficult to grasp the difference visually.

Until now, the technology has succeeded in observing the bloom from the initial stage of the chocolate surface development, from the ejection of liquid oil to the growth of the bloom, at the nanometer level using a scanning probe microscope (SPM). ing. (Non-Patent Documents 1 and 2)
Patent Literature 1 considers the “gloss” of chocolate to be the effect of surface irregularities, and attempts to observe the chocolate surface using SPM in order to see the relationship between glossiness and surface irregularities.
However, SPM is capable of observing a morphological change at the nano level in the early stage of generation due to its measurement principle, but it is difficult to catch a change in a wide field of view. In addition, SPM can measure an ultra-fine form, but requires skill in operation, and has a problem of lack of versatility.
On the other hand, there is a report that the surface state is observed by profilometry or LV-SEM (low-vacuum scanning electron microscope) to check for irregularities. (Non-Patent Document 3, Patent Document 2)
Further, in Non-Patent Document 4, evaluation is made on the shape image and the obtained roughness and waviness from the measurement results of profilometry.
In these papers and inventions, the change in surface structure due to the occurrence and growth of bloom is evaluated using the index of "surface roughness" used for evaluation of luster, but has a poor quantitative property.

Japanese Unexamined Patent Publication No. 2007-512822 JP 2003-534017 A

Rousseau, D. On the porous mesostructure of milk chocolate viewed with atomic force miscroscopy, LWT Food Sci. Technol., (2006) 39, 852-860. Rousseau and colleagues published their study in the Journal of the American Oil Chemists Society (Microscale Surface Roughening of Chocolate Viewed with Optical Profilometry.Journal of the American Oil Chemists Society, 2010; 87 (10): 1127-1136). P. Bondioli, A. Gasparoli, L. Della Bella and S. Tagliabue, Eur. J. Lipid Sci. Technol., 104, 777 (2002). Rizwan S. Khan, Derick Rousseau, Hazelnut oil migration in dark chocolate-Kinetic, thermodynamic and structural considerations, European Journal of Lipid Science and Technology 108 (5): 434-443 (2006).

An object of the present invention relates to a method for observing a surface microstructure in an oil / fat composition in which the oil / fat is a continuous phase, and more specifically, a bloom of an oil / fat composition, particularly an oily food, occurs more quickly based on the above observation method. It is an object of the present invention to provide a method for predicting the possibility of an early stage.

  The inventors of the present invention have conducted intensive studies in view of the above points, and have found that a concave structure dug below a reference surface generated on a surface structure B, which is a convex structure having a low surface microstructure and a wide width, or a periphery thereof. By observing at least one change in the surface structure B ′, which is the structure, it was found that bloom was predicted, and the present invention was completed.

  That is, the present invention provides, as (1), a sign of the occurrence of bloom, in which a change in at least one of the surface structure B and the surface structure B ′ of the surface microstructure is used as an index in an oil or fat composition in which the oil or fat is a continuous phase. However, the surface structure B is a convex structure of a fat crystal having a short height and a wide width generated above the reference plane, and the surface structure B ′ is formed around the surface structure B below the reference plane. Each refers to a dug concave structure. (2) A method of capturing a sign of the occurrence of bloom described in (1), wherein at least one change of the surface structure B or the surface structure B ′ is a change in volume, and (3) a method of capturing 3D profilometer, LSM, The present invention relates to a method for detecting a sign of bloom occurrence according to claim 1 or 2, wherein one or more kinds of observation instruments selected from SPM, AFM, SEM, and CT are used.

According to the present invention, by observing a change in at least one of the surface structure B or the surface structure B ′ of the surface microstructure, more specifically, by observing the volume change using an observation instrument that can measure the volume change, By distinguishing the surface structure A and the surface structure B or the surface structure B 'that could not be distinguished in the past, and the size can be quantitatively evaluated as a volume or area, in the quality evaluation of chocolate In addition, the period of the storage test can be significantly reduced.

It is a schematic diagram which shows the typical shape of a surface structure. It is a schematic diagram which shows a time-dependent change of a surface structure (early stage of surface structure A generation). It is a schematic diagram which shows a time-dependent change of the surface structure (early stage of surface structure B generation). It is a schematic diagram which shows the time-dependent change of surface structure (surface structure B extension period). It is a drawing substitute photograph which shows observation of a surface structure by LSM (laser image). It is a drawing substitute photograph which shows observation of the surface structure by LSM (height image). It is a drawing substitute photograph which shows observation of a surface structure by LSM (3D image). It is a drawing substitute photograph which shows the observation of the surface structure by LSM (DIC image). It is a drawing substitute photograph which shows the surface structure A by Cryo-SEM (observation magnification 250 times). It is a drawing substitute photograph which shows the surface structure A by Cryo-SEM (2000-fold observation magnification). It is a drawing substitute photograph which shows the surface structure B by Cryo-SEM (observation magnification 250 times). It is a drawing substitute photograph which shows the surface structure B by Cryo-SEM (2000 observation magnification). It is a drawing substitute photograph which shows surface structure B 'by Cryo-SEM (2000-fold observation magnification). It is a drawing substitute photograph which shows observation of the time-dependent change of the surface structure by LSM (3D image). It is a drawing substitute photograph which shows the position of the cross section profile by LSM (3D image). It is a drawing substitute photograph which shows the cross-sectional profile by LSM. It is a figure which shows the relationship between a preservation period and the maximum mountain height and the maximum valley depth. It is a figure which shows the relationship between a storage period and the area ratio of a convex part and a concave part. It is a figure which shows the relationship between the storage period and the volume of a convex part and a concave part.

(Oil composition)
Refers to a fat composition in which the fat is a continuous phase. Solids and moisture may be present in the form contained in the continuous phase. Since the surface structure of the oil / fat composition is generated by solidification of the oil / fat to form crystals, it is only necessary that the crystal part of the solid fat has a surface structure at the time of measurement, and its melting point and the like are not particularly limited.
The fat or oil composition to be observed may not be a food as long as the fat or oil is a continuous phase and the surface structure is changed by growing crystals. Examples include wax surfaces, oily foods, and the like.
An oil / fat composition having a commercial value when it becomes whitened or mottled due to a change in the surface structure, for example, a chocolate-like food is particularly suitably used.

(Oily food and chocolate)
The oily food in the present invention is not particularly limited as long as it is a food in which fats and oils form a continuous phase, but examples thereof include chocolate, chocolate-like foods, and glaze-like foods (sugars dispersed in fats and oils). Used for purposes such as overhanging) and solid curry roux.
Also, chocolate includes "chocolate dough" and "quasi-chocolate dough" according to the "Fair Competition Regulations on Labeling of Chocolate" (March 29, 1967, Notification No. 16 of the Fair Trade Commission). Cocoa mass prepared from cocoa beans, cocoa butter, cocoa powder and sugar as raw materials, if necessary, other edible oils and fats, dairy products, flavors, etc. are added, and those that have undergone the process of chocolate production are called so-called whites that do not use cocoa mass. It also includes chocolate dough.
Further, the chocolate-like food refers to foods that include so-called no-tempering type chocolates that do not require a tempering operation, in addition to conventional chocolates (many require a temperature operation called tempering at the time of production).

(Storage conditions)
Over time, the surface structure of the fat or oil in the fat or oil composition changes due to crystal growth or crystal transition. The state is called preservation, and the temperature is called preservation temperature. The storage temperature may fluctuate. In addition, even when the temperature exceeds the melting point of fats and oils, not all solid fat crystals are instantaneously melted to become a liquid, but some remain, and the remaining crystals are used as seed crystals to grow new crystals and surface structure. To form Furthermore, since the surface structure of the crystal growth is different from that in the state where the seed crystal is present even from the state where the seed crystal is completely melted once to the state where the seed crystal is cooled, the upper limit of the storage temperature is not particularly limited.
In some cases, the crystals are promoted by mediating liquid fats and oils by raising or lowering the storage temperature.Store the crystals under temperature changes according to the situation where the product is placed, or store them under more severe conditions. In some cases, a change in the surface structure may be observed at an earlier stage. Therefore, the temperature during storage may not be constant and can be set as appropriate.
The above-mentioned preservation for changing the temperature includes what is called a cycle test. The pattern of the temperature change is appropriately set according to the type of the fat or oil composition. Examples of the case where the fat or oil composition is chocolate include various kinds such as 17C to 28C, 18C to 25C, 18C to 28C, and 17C to 32.5C. In some cases, the temperature may reach 40 ° C., which is higher than the melting point of the fat for chocolate. Even then, the chocolate of interest does not completely melt and solid fat crystals remain. The transition of the temperature is performed over a period of about 1 to 2 hours, and is often repeated in a 24-hour cycle.

(Composition of fat composition)
The content of the fat or oil is not particularly limited as long as the fat or oil is in a continuous phase and a change in the surface microstructure of the fat or oil composition can be seen. The upper limit may be 100% by weight composed of only fats and oils. On the other hand, if there is no oil or fat, it cannot be formed into an oil or fat composition, so it must be contained at least. That is, although the content is not particularly limited, it is desirable that the amount of the fat or oil is 10% by weight or more and 100% by weight or less, preferably 20% by weight or more based on the whole fat and oil product.
Further, as described above, since the fat or oil can be 100% by weight with respect to the whole fat or oil product, the amount of solid content used in the fat or oil composition is not limited, and may be 0% by weight. In addition, since it may be 0% by weight, the type of solid content is not particularly limited. If the oil or fat composition is an oily food, for example, curry roux, the spices used for flour and curry are finely ground, but among the oily foods, sugars and milk powder, chocolate, cocoa solids, matcha powder, fruits Powders, nuts and the like can be mentioned. Furthermore, as long as the fat or oil of the oily food is in a continuous phase, it may be combined with another food. Examples include chocolate pasted on biscuits and chocolate chips buried in cookies.

(Oil of fat composition)
The type of fat used in the fat composition is a triacylglyceride having a symmetrical molecular structure as a main component, and a tempering operation is required (tempered). Chocolate-like food, laurin, or treatment such as hydrogenation or random transesterification. (Tempered) that does not require a tempering operation (no-tempered), and contains a large amount of liquid fats and oils, so that high-melting fats and oils with a soft texture are agglomerated to form a hard granular composition. (Graining) Western chocolate-like foods, and those chocolate foods that contain a lot of oils and fats having a molecular structure different from those used in other oil-based foods such as shortening, such as chocolate-like foods. Chocolate parts such as chips-containing cookies.
As the solid fat crystals of the oil / fat composition grow, the surface structure becomes disordered and the rate of irregular reflection of light on the surface increases, so that the surface becomes white or mottled. This is called bloom.
In addition, although the above-mentioned graining is also classified and included in bloom in a broad sense, in the present invention, in order to pay special attention to a phenomenon associated with a change in surface structure leading to whitening, it is simply referred to as bloom. Does not include this graining.

(Method for observing surface microstructure)
The surface microstructure refers to a crystal in which a fat or oil forming a continuous phase of the fat or oil composition grows and appears on the surface. The present invention predicts bloom by distinguishing from the surface structure other than the surface structure B or the surface structure B ′ in order to use the change of at least one of the surface structure B and the surface structure B ′ as an index among the surface microstructures. be able to.
For that purpose, it is necessary to be able to measure three dimensions. Here, three-dimensional refers to two axes (directions belonging to the plane and a specific horizontal direction (x-axis)) which are directions along a plane constituting the surface of the oil and fat composition, and also belonging to the plane and belonging to the vertical direction. Observation methods that can measure the vertical direction (y-axis), which is perpendicular to the plane, and the height direction (z-axis), which is perpendicular to the plane (ie, the x-axis and the y-axis). is necessary.

(Surface microstructure observation method)
Here, a method for observing the surface microstructure will be described in detail. Conventionally, there has been an observation device for measuring the height of a surface from a reference plane for observing the surface microstructure of an object. Examples include conventional SPM for measuring "surface roughness", profilometry, and LV-SEM. However, it is shown by observing the volume fluctuation of the present invention that the change of the surface microstructure actually changes in the following course. This is insufficient because the initial movement of the microstructure may be missed. Also, 2D Profilometer and Raman / FT-IR, which cannot obtain three-dimensional (height direction) information, are not desirable.
The device to be used is not particularly limited as long as the device satisfies the requirement that the volume fluctuation of the surface microstructure described below can be measured. Preferably, 3D Profilometer, SPM, AFM (Atomic Force Microscope, a kind of SPM), SEM (Scanning Tunneling Microscope), CT (Computed Tomography) are preferable, and especially 3D Profilometer, especially LSM (Laser Scanning). Microscopy) is desirable.
In the prior art, the conventional SPM is not desirable because it can measure only the height. However, by adding an additional option to the measuring device, the volume fluctuation can be measured. As long as it satisfies the requirement that the measurement can be performed, an example of the observation apparatus which is desirable for solving the problem of the present invention is adopted. Naturally, conventional SPMs that can only measure height can discriminate two or more completely different surface structures, as shown below, if volume fluctuations cannot be measured, even if the height itself is highly accurate. And its use is undesirable.
In addition, it is difficult to make continuous measurements with an observation device, or a high vacuum is applied at the time of measurement, and there are many damages to the sample to be observed. At that point, the LSM can be repeatedly observed nondestructively. Especially desirable.

(Surface microstructure analysis method)
After measuring the surface microstructure using an observation device, it is necessary to analyze the measured value with an analysis device. Some observation devices are provided with an analysis device. However, there is no particular limitation as long as information obtained using an observation device capable of obtaining information on length, width, and height can be analyzed. An example is "MountainsMap (registered trademark)" by Digital Surf.
According to these analysis methods, the three-dimensional information of the surface microstructure is visually recognized by actual image information, or the following changes in the surface structure B or surface structure B ′ of the surface microstructure are captured as three-dimensional information, and the change is detected. Can be used as an index to predict bloom.

(Shape of surface microstructure)
The information obtained when the surface microstructure of the measurement object is measured by a measuring instrument is as follows, and the correspondence is shown in FIG.
The fat and oil composition to be measured has a surface to be observed, and each time the surface is measured, a plurality of portions with less unevenness of the surface structure are specified in the measurement field of view every time the measurement is performed. Is referred to as a reference plane (G in FIG. 1). This is a reference for defining the following Sp and Sv.

(Change in surface microstructure over time-using chocolate as an example)
In examining the change in the surface microstructure of the oil / fat composition, a specific example of chocolate, which is an oily food, will be described.
Chocolate causes a phenomenon in which the fat component constituting it becomes coarser due to crystal transition with time, and by accumulating changes in the surface microstructure, it eventually becomes a bloom that can be confirmed with the naked eye, leading to damage to the commercial value .
However, the detailed behavior at the very beginning was not known about the change of the fine surface structure. However, the present invention has revealed one of them.
As an example, using the three-dimensional measurement information of the present invention instead of the conventional observation of only the height, for example, in the case of solidifying the sweet chocolate without performing the tempering operation and observing its fine surface structure at 20 ° C. This shows that observation by volume change is particularly suitable.

First, in the initial stage of storage, a projection (surface structure A, A in the figure) that is taller than the area grows due to crystal growth. In observation by conventional height, a value appears as Sp, which is the maximum peak height of the surface structure A. Note that in the case of a surface structure having a certain degree of isotropicity, the fact that the surface is taller than the area may be approximated as being taller than the maximum length of the diameter of a portion corresponding to the area. Further, it is prescribed again how the height of the surface structure A is distinguished from the surface structure B or the surface structure B '(postoperative) with respect to the area (diameter). (Fig. 2)
However, short protrusions (surface structure B, B in the figure), which could not be known by the conventional idea, start to grow immediately after this irrespective of the surface structure A. However, the conventional observation with the height still shows Sp, which is the maximum peak height of the surface structure A.
The surface structure A also gradually grows, and Sp increases. However, since the surface structure B grows in the form of expanding in the lateral direction, Sp is maintained at a maximum peak height of the surface structure A even when the storage period is advanced. , The existence of the surface structure B does not appear at all in the numerical value of the observation. At this point, the bloom on the appearance is completely invisible to the naked eye. (Fig. 3)

Although the surface structure A also grows, the increase in Sp reaches a plateau, but the surface structure B rapidly expands in the lateral direction. Sp still shows the maximum peak height of the surface structure A, but the surface structure B is large in volume, albeit low, and due to the growth of the surface structure B, the oil and fat near the surface layer around the surface structure B (FIG. 4) (FIG. 4). In this case, since the chocolate is chocolate, a solid content remains, and the solid content of the surface structure B and the surface structure B 'which spread widely spread rapidly lowers the reflectivity of the surface. After that, the surface structure B and the surface structure B ′ gradually continue to spread, so that the appearance finally becomes so-called bloom, which is a degree of whiteness that can be observed with the naked eye.

Here, it is the surface structure B and the surface structure B ′ that are actually considered to be the main cause of the bloom by visual observation, but since the height of the surface structure A is extremely different from the surface structure A, it is difficult to be observed by the measurement based on the height. , Appearing as a value is the maximum peak height of the surface structure A. In this case, the surface structure A is considered to be grained, does not grow much in the direction of the surface, and also grows in the height direction (Z axis) at a certain point, and reaches a plateau. Although there is a feeling of granular foreign matter, this is one of the factors for lowering the quality of the oil and fat composition, but it cannot be a main factor in the appearance.
The graining (surface structure A) and the bloom are generated by different mechanisms. In some cases, the surface structure A does not lead to bloom, which is a whitening phenomenon of the surface, while the surface structure A is generated. It cannot be a predictable material.
Therefore, the conventional observation of only the height only shows the behavior of the surface structure A, which is not directly related to the whitening phenomenon in bloom, but directly affects whitening by using the three-dimensional measurement information of the present invention. The behaviors of the surface structure B and the surface structure B ′ having the presence can be grasped.

As described above, the fine structure of the surface is largely divided into a surface structure A extending mainly in the height direction (Z-axis) and a spine generated above the reference surface (z-axis) of the fat / oil composition surface. There is a surface structure B, which is a convex oil and fat crystal having a low width and a wide width, and a surface structure B ', which is a concave structure dug below the reference plane, around the surface structure B. Bloom can be predicted by using the change of the connected surface microstructure, that is, the surface structure B as an index.
The surface structure B and the surface structure B ′ have the same mechanism, and the surface structure B ′ is dug widely as the surface structure B grows.

(How to distinguish surface structure B and surface structure B 'from surface structure A)
The surface structure B and the surface structure B ′ can be found by visualizing information obtained by an observation device capable of measuring three dimensions by an analysis device, and bloom can be predicted.
As described in the mechanism of occurrence, the surface structure A protrudes sharply from the reference plane, and has a rock-like shape suddenly appearing on a smooth plane. On the other hand, the surface structure B has a shape in which the fat and oil crystals are spread thinly in the horizontal direction on a plane, and the grass is prosperous. The surface structure B 'is exposed as a material on which the surface structure B grows by absorbing fats and oils on the surface, so that solids (such as sugar and cocoa solids in the case of chocolate) are exposed, as if the topsoil was washed away by rainwater, Pebble will be exposed.
In order to distinguish the surface structure A from the surface structure B and the surface structure B ′, the following method can be considered.
That is, if the ratio of (maximum length in the Z-axis direction) / (maximum length on the plane to which the x and y axes belong) of the target independent surface structure is 0.1 or more, preferably 0.2 or more, and more preferably 0.5 or more. If it is a surface structure A, less than 0.1, preferably less than 0.08, more preferably less than 0.05, it can be considered a surface structure B. Note that the maximum length in the Z-axis direction is an absolute value, and may be in the negative direction (that is, “dug” below the reference plane), and the surface structure B ′ is based on the same reference as the surface structure B. I can judge.
In addition, an independent individual refers to a region surrounded by a closed line having a height of 0.

(Bloom prediction due to volume change)
As described above, at least one of the surface structure B and the surface structure B ′ is found by visualizing the information obtained by the observation device capable of measuring three dimensions by the analysis device, the surface structure A is identified, and the change in the surface structure is performed. Although it is possible to predict changes in the surface structure leading to bloom at a very early stage, a method for predicting bloom by volume change will be described.
In the present invention, it is desirable to use a measuring method capable of measuring the volume of the convex part (part B in FIG. 4) and the concave part (part D in FIG. 4) which are upward from the level surface. (Part B in FIG. 4) It is desirable to measure the volume of the concave portion and the convex portion over time. For this purpose, the visual field is fixed in the same state, and the reference surface (G in FIG. 1) is used. It is desirable that the volume of the concave / convex portions can be obtained by measurement. In addition, although the above-mentioned preferred instruments for observation are described above, an observation or analysis apparatus capable of measuring not only height (z-axis) information but also surface (x-y-axis) position information by adding a program. The device is not particularly limited as long as three-dimensional information can be observed by adding it.

(Reference plane (x / y axis) direction accuracy)
The reference plane direction is, as shown in FIG. 1G, a direction along a plane constituting a reference plane that defines the heights of the upwardly protruding portion and the downwardly concave portion, and the resolution in the reference plane direction is as follows. It is necessary to observe the first occurrence of the surface structure A. On the other hand, the surface structure B, which has a shape that is widely spread in the direction of the reference plane, is generated later than the surface structure A and the size of the surface structure in the reference plane direction is larger than that of the surface structure. Greater than A. Therefore, it is desirable that the surface structure A can be confirmed at the time when the surface structure A has grown beyond the height described later. The resolution in the reference plane direction is 10 μm or less, preferably 5 μm or less, and more preferably 1 μm or less. It is desirable to measure

(Height (z-axis direction) accuracy)
Height (z-axis direction) Accuracy It is desirable to measure the fluctuation of the height of the microstructure with an accuracy of 1 μm or less, preferably 0.5 μm or less, and more preferably 0.2 μm or less, to measure the volume fluctuation.
If the accuracy is at least 1 μm, the volume fluctuation of the surface structure B can be observed. Since the volume fluctuation A is much larger than the volume fluctuation B or the surface structure B ′, the difference can be sufficiently observed.

(Bloom prediction due to volume fluctuation)
It is desirable to measure the volume variation of the surface microstructure by measuring the volume variation with an accuracy of 10 μm ³ or less, preferably 5 μm ³ or less, more preferably 1 μm ³ or less.
Observe volume fluctuations with this accuracy. As described in the case of the change of the surface microstructure with the lapse of time in the case of chocolate, the surface structure A has a gradual increase in the bottom area, a sharp rise in its height, and reaches a plateau at a certain point. That is, the volume fluctuation accompanying the growth of the surface structure A largely depends on the extension of the height (z axis). On the other hand, unlike the surface structure A, the surface structure B gradually increases in height in the surface direction (x and y axis directions), although the increase in height after generation is slow. That is, the volume fluctuation accompanying the growth of the surface structure B (and the accompanying surface structure B ′) largely depends on the extension of the plane (in the x and y axes directions), and the surface structure A which depends on the height of the first power term. And the surface structure B depending on the square term, which is a plane, the surface structure B greatly increases. Therefore, it is easier to see the increase in the surface structure B by looking at the volume fluctuation.
In particular, there is no specific rule for catching the increase, but it can be predicted from the fact that the amount of the increase is sharply increased in a graph or the like.

(Forecast of bloom due to area change)
In addition, as described above, the point that a bloom can be predicted by a volume change analyzed based on information obtained by an observation device capable of measuring three dimensions is as described above, but two dimensions (area) based on three dimensional information are as described above. Describe a method of predicting bloom based on fluctuations.
That is, it is to observe the change in the area of the portion where the height data is positive, that is, the area that is raised above the reference plane, and the area that is negative, that is, the area that is dug below the reference plane.
As described in the above mechanism, the surface structure A has a tendency that the fluctuation of the height rapidly increases and then flattens, but the portion corresponding to the bottom surface is not so large. This means that the increase in area is small.
On the other hand, the surface structure B is characterized in that although the fluctuation in height is not so large, the portion corresponding to the bottom surface rapidly expands. This indicates that the increase in area is large.
Further, the surface structure B ′ has a large increase similarly to the surface structure B, and the surface structure A itself does not cause a phenomenon such as the surface structure B that the surroundings are depressed so much. It can be more desirably used because it is easily connected to the increase in the surface structure B.

  As shown above, the observation of the surface structure B or surface structure B 'of the surface microstructure, and the observation of the volume fluctuation using an observation instrument capable of measuring the volume fluctuation, have conventionally distinguished the occurrence. By distinguishing the surface structure A and the surface structure B or the surface structure B ′ that could not be formed, and by being able to quantitatively evaluate the size as a volume or an area, the storage test in the quality evaluation of chocolate is greatly improved. It is possible to shorten the period.

Hereinafter, the effects of the present invention will be clarified by illustrating examples, but the spirit of the present invention is not limited to the following examples. In addition,% and a part mean a weight basis in an example.
Experimental example 1 (mixing of chocolate, manufacturing method)
In 90 parts by weight of commercially available sweet chocolate (oil content: 35.3%, manufactured by Fuji Oil Co., Ltd.), 10 parts by weight of cocoa butter (trade name: Cocoa Butter 201, manufactured by Fuji Oil Co., Ltd.) is added, and completely immersed in a hot water bath. After dissolution and mixing, the mixture was cooled to 30 ° C., poured into a mold, and solidified at 10 ° C. for 30 minutes. In addition, since it was the purpose of grasping the change of the surface microcrystal in the early stage of preservation, chocolate was prepared under the conditions of no seeding agent added and no tempering.
The chocolate was transferred to a laboratory at a constant temperature of 20 ° C. and used as a material for evaluation.

(Fixed point observation with laser microscope)
Using a laser microscope (Laser Microscope (3D & Profile Measurement, hereinafter referred to as LSM) and Keyence VK-X150 (hereinafter referred to as LSM), fixed-field observation was performed with the field of view fixed. 5), four types of images, a height image (FIG. 6), a 3D image (FIG. 7), and a differential interference image (hereinafter referred to as a DIC image, which can display surface irregularities simply) (FIG. 8) can be obtained. Using a 50 × lens, continuous images of 4 × 4 were obtained and analyzed according to two purposes: single images or connected images (16 images connected).
At the time of observation, the atmospheric temperature was kept at 20 ° C. ± 1 ° C., and a field of view of 1500 × 1000 μm was fixed, and the measurement was performed over time for 7 days. Based on the observation data, the surface roughness and unevenness (volume / surface area) were analyzed using the multi-file analysis application attached to Keyence's LSM. When the whole image is mainly a connected image and more detailed analysis is required, a single image is used to avoid noise due to image connection.

(Cryo-SEM observation of fine surface structure)
After the storage test is completed, a sample 8 days after the storage test (hereinafter referred to as D + 8, where the number after + is the number of days elapsed) is cut out, and 20 mA using an osmium plasma coater (HPC-20, HOLLOW CATHODE PLASMA CVD, vacuum device). × 15 sec. Evaporated to obtain an observation sample. The sample was observed under an atmosphere of -160 ° C using a HITACHI SU3500 scanning electron microscope (Gatan Alto-1000 Cryo-Unit).
Because it is difficult to find the position where the fixed point observation was performed by LSM, the SEM was to observe the vicinity of the LSM field of view. The observation area of the Cryo-SEM was measured in advance by LSM, and the surface condition near the observation position was confirmed.

Observation of the shape of the fine surface structure by Cryo-SEM is difficult to understand from the image, but the precise shape and size along the surface direction can be sufficiently observed. From the properties of the observation device, it is not possible to ensure the same field of view as the LSM, but the fine surface structure belonging to the same classification as the surface structure A, surface structure B, and surface structure B 'observed by the LSM is not I can clarify.
9 and 10 show a surface structure having a maximum length of 9 to 15 μm and shaped like a steep rock.
FIGS. 11 and 12 are already large enough to overflow the field of view, have a maximum length of 200 μm or more, and have a surface structure in a shape like grass growing. FIG. 13 shows a surface structure having the same shape as that of FIG. 12 and a surface structure in which solids such as small rocks and gravel remaining after the topsoil flows out are exposed. Therefore, it can be seen that the surface structure A has the shape shown in FIGS. 9 and 10, the surface structure B has the shape shown in FIGS. 11 and 12, and the surface structure B 'has the shape shown in FIG.

(Measurement by LSM (3D image))
FIG. 14 shows a 3D image at the same position from D + 0 to D + 5.
From black to dark gray, gray, light gray, and white, the closer to white, the higher the structural position. (Although the original analyzer can express the height in color for better visibility, the present invention expresses the height by gray gradation from black to white. Since A is extremely large as compared with many structures, the gray gradation is controlled so that the gradation is obtained with more emphasis on the surface structure B. Therefore, the surface structure A is light gray and the gradation is relatively high. Although there is no expression, the size of the surface structure A can be understood by giving a slope.
From D + 2, a small granular structure appears on the surface, and the number increases with the passage of days. The structure formed near the center at D + 3 spreads concentrically with D + 4 and D + 5.

Due to the morphological features, the surface structure A becomes taller but the growth reaches a plateau, and the area corresponding to the bottom does not greatly expand, while the surface structure B and the surface structure B ′ greatly spread over the surface and roughen the surface structure. It can be estimated that. However, at this time, no bloom was found at all, since the surface was not glossy, and the bloom was visually observed after D + 8.
Here, (maximum length in the Z-axis direction) / (maximum length on the plane to which the x and y axes belong) of the independent surface structures regarded as the surface structures A and B are obtained.
At time D + 6, three-dimensional data is obtained. Originally, the observation device measures three-dimensional data, and the attached analysis device analyzes and obtains the height and 3D image from the obtained 3D information electronically. Height data is acquired in the form of a cross section connecting A and the surface structure B (FIG. 15, line segment C1C2). (FIG. 16)
A sharp peak at the left end is referred to as a peak A, and a peak having a large central width but a low height is referred to as a peak B. The height of peak A was 15.56 μm and the width was 19.23 μm, the height (depth) of peak B was 5.31 μm, the width was 179.62 μm, and the height of peak B ′ was 3.07 μm and the width was 385.90 μm. Was.
From this, (maximum length in the Z-axis direction) / (maximum length on the plane to which the xy axes belong) of the surface structure corresponds to the maximum length on the plane to which the xy axes belong. Since the shape of the structure is concentric, the width in this section may be regarded as the maximum length.) Since the height corresponds to the maximum length in the Z-axis direction, the peak A is 0.809 and the peak B is 0.030 and peak B 'were 0.008.
Therefore, peak A is classified into surface structure A, peak is classified into surface structure B, and peak B 'is classified into surface structure B'.
In addition, it is possible to determine whether the surface structure is the surface structure A or B from the data of the cross section. However, if the 3D image is not known, the cross section cannot be set to the correct maximum peak height of the peak. Therefore, it is difficult to predict the occurrence of bloom based on the surface structure.

Since the height information (Sa, Sz, Sp, Sv) from which the height image is calculated and the position information of the convex part and the concave part position are obtained from the height data, the area of the convex / concave position is obtained. And the volume (μm ³ ) was obtained from the area ratio (% with respect to the visual field) and the height information in that region. (Table 1)
As described above, it was verified whether it is possible to detect the surface structure A (graining), the surface structure B, and the surface structure B ′ based on the obtained information.

(LSM data analysis (surface roughness))
First, paying attention to the maximum peak height Sp, the maximum valley depth Sv, and the step Sz, the values are shown over time to show the behavior.
FIG. 17 shows graphs of Sa (average peak height) and Sz (maximum peak height) which are conventionally used indices of surface roughness. The surface roughness (Sa, Sz), particularly the step, changes greatly from D + 1 to D + 2. This is faster than the shape information changes. The surface structure A has already been generated on the second day of storage and Sp has a large peak. However, since the surface structures B and B ′ generated thereafter are all smaller than the surface structure A, three days have elapsed. All the increases in Sp after the eye were due to surface structure A. On the second day, the surface structure B 'also shows its signs, and on the third day, it is definitely seen. On the fourth day, the unevenness rapidly spreads over the entire surface, but it can be seen from Sv. Can not.
Since the surface structure A can be seen from the DIC images (FIGS. 9 and 10), the surface structure B and the surface structure B ′ (FIGS. 11 and 12), and the blooming that spreads over the entire surface thereafter can be seen as graining. The occurrence of the Sp value of the surface structure A (day 1) and a sharp rise (day 2) cannot be regarded as a final sign of the occurrence of bloom.

(LSM data analysis (volume / area ratio))
FIG. 19 is a graph showing the volume and FIG. 18 is the area ratio of the convex and concave portions based on the measured data. The area ratio is the ratio of the target range to the visual field. And although it is the area ratio, being above (convex portion) or below (concave position) from the reference plane means that if it is not possible to measure the height in a specific region, it is impossible to judge whether it is any portion of unevenness, This measurement method cannot be obtained without all three-dimensional measurement values.
Both the volume and the area ratio increased remarkably from D + 3, and in particular, the volume showed logarithmic growth. This coincides with the time of surface change in the LSM image. When the unevenness was further evaluated separately, the volume of the convex portion was remarkably increased with respect to the concave portion.
In the area ratio, the increase in the area of the concave portion was more remarkable, but this was probably because the surface structure A was growing in the vertical direction. In the volume, it was confirmed that the number of protrusions (surface structure B) was remarkably increased.
From these results, it can be seen that in order to quantitatively evaluate the growth of bloom, the evaluation can be made based on the movement amount (volume) of the fat or oil, and also by observing the area ratio in consideration of the height information.

G: Reference plane B: Part (projection) projecting upward from the reference plane
D: Portion recessed from the reference plane (recess)
Sp: the maximum peak height of the convex portion in the region Sv: the maximum valley depth of the concave portion in the region Sz: the maximum height (step) Sa corresponding to Sp + Sv: the average of the absolute value of the concave and convex from the plane, Sz / Line segment C1-C2 corresponding to 2: line segment from which height data was acquired

According to the present invention, by observing the surface structure B of the surface microstructure, and further observing the volume fluctuation using an observation instrument capable of measuring the volume fluctuation, the surface structures A and B, whose generation could not be distinguished in the past, can be distinguished. By discriminating the quality of the chocolate and quantitatively evaluating the size as a volume or area, it was possible to significantly shorten a storage test period in chocolate quality evaluation.

Claims (3)

A method for capturing a sign of bloom occurrence in an oil / fat composition in which the oil / fat is a continuous phase, using a change in at least one of the surface structure B and the surface structure B ′ of the surface microstructure as an index.
However, the surface structure B is a convex structure of a fat crystal having a short height and a wide width generated above the reference surface, and the surface structure B ′ is a concave structure dug below the reference surface around the surface structure B. Refers to each structure. 2. The method for predicting bloom occurrence according to claim 1, wherein the change in at least one of the surface structure B and the surface structure B 'is a volume change. 3. The method for capturing a sign of bloom occurrence according to claim 1 or 2, wherein at least one observation device selected from a 3D profilometer, LSM, SPM, AFM, SEM, and CT is used.