JP3009778B2 - Gel substitute for fat and food containing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a whey protein liquid composition, a whey protein liquid emulsion, and a gel obtained by gelling the same. The gelled product itself can be used as a novel food having a unique texture, and can also be used as a fat substitute, a bulking agent and a stabilizer.

[0002]

2. Description of the Related Art Whey contains many nutritious components such as proteins, carbohydrates and minerals among its components. Reports have been made. With respect to whey protein, its use in foods has been studied by applying its functions such as solubility, foaming property, emulsifying property, and gelling property. However, research is still in its infancy, and there are still many unknowns in terms of functionality. For example, regarding gelation, most of the means is ultimately performed by heating, and there are few known examples in which gelling means other than heat treatment is mainly used.

[0003] With respect to utilization in foods, a method is known in which lactic acid fermentation of whey protein is carried out, the pH is lowered to below the isoelectric point, and the whey protein is used as a fermented beverage based on it.
341 and JP-A-62-40248. These are used to convert whey protein solution to a pH below the isoelectric point.
It is adjusted to 2.5 to 3.5 and used as an acidic beverage. In the method described therein, the carbohydrate content in the fermentation liquor is higher than the protein content (the protein content is lower), and the saccharide is further added to this fermentation liquor in a large amount of 20 to 40%. Even at a pH below the isoelectric point, aggregation and precipitation of proteins are suppressed, and acidic beverages in a solution state are obtained.

[0004] In addition, glucono delta lactone (hereinafter referred to as GDL) is added to whey protein to obtain a gel which has a higher gel strength than egg protein, has no sulfur odor, and has no water separation, and uses this as a substitute for egg protein. Is disclosed in Japanese Unexamined Patent Publication No.
No., published in Japanese Unexamined Patent Publication No. It is thought that the main purpose of this technique is to prevent the aggregation of whey protein and obtain a uniform gel by heating the whey protein solution and then gradually lowering the pH. GDL is the most suitable means for gradually lowering the pH. However, this report does not describe a specific range of pH and its effect, and it is unclear whether the phenomenon is peculiar to GDL, the effect of pH, or the effect of isoelectric point.

[0005] Further, the interaction and the effect when whey protein is mixed with a milk protein material and fats and oils are not specifically described, and no report is made utilizing the characteristics thereof.

[0006]

However, in the above-mentioned prior art, the heating means and other auxiliary means cannot be separated from each other as a gelling operation of whey protein, so that there are restrictions on the processing operation, and there is also a disadvantage in the conventional method. The obtained gel has a very limited texture as a food material, and has poor functionality from the viewpoint of food processing properties, and thus its use has been limited. The present invention has been made in view of the above-described prior art, and has been made to make whey protein excellent in nutritional value widely available as various food materials, and cannot be obtained with a conventional heat-coagulated gel. It is intended to obtain a smooth gel having good water retention and the like without being limited to heat treatment, and to obtain a versatile food material having high texture and functionality.

[0007]

This object is achieved by the following means. That is, the present invention specifically denatures whey protein and has a hydrophobicity of 50 [FI / mg protein.
n] greater than or equal or is whey protein solution to 100 parts by weight of 20% or more is made of a molecular weight of 1,000,000 or more aggregate of its total protein to other proteins material 0.1-200
Whey protein liquid composition comprising parts by weight, or
With respect to 100 parts by weight of the whey protein solution, 0.1 g of fats and oils was added.
Fat obtained by using a whey protein liquid emulsion containing 1 to 200 parts by weight and lowering the pH thereof to a range having the isoelectric point of whey protein as a lower limit.
It is an alternative gel. Further, the present invention provides
It is a food containing a fluoride.

[0008] A feature of the present invention is that whey protein is denatured to a limited extent, and other proteins or fats and oils are mixed with the resulting solution, so that the pH is adjusted to a range having the isoelectric point as a lower limit. To obtain a gelled product.

Very little is known about the interaction and the effect of mixing whey proteins with proteins and fats and oils, and these are considered to have a pH above the isoelectric point.
The characteristics of the gelled product obtained by adjusting the temperature were not known.

As a means for denaturing whey protein in a limited manner, not only a heat treatment but also a high pressure treatment, an organic solvent treatment or the like can be employed as long as it causes denaturation of protein molecules.

The gelled product of the present invention has a unique feature which cannot be obtained by whey protein alone by utilizing a unique action and effect which is exhibited only when proteins, especially milk proteins and fats and oils are mixed. . That is, by adding milk proteins, a gel having a fat-like texture with less acidity and richness can be obtained. Since this gel is soft and easy to mix uniformly with other materials, it can be used as a fat substitute or bulking agent.
Water retention can be improved. On the other hand, the addition of fats and oils provides a gel with less acidity and richness and good mouthfeel. This gel has particularly high water retention and does not cause water separation. Further, since the gel is soft and easily mixable with other materials, it can be mixed with other foods to give smooth texture and richness.

Furthermore, these gels also have heat resistance and are effective as food processing materials.

In the present invention, the degree of hydrophobicity means a value defined below.

Hydrophobicity: An appropriate concentration of whey protein (0.
(About 1-0.3 g / l), 8 mM 1-anilinonaphthalene-8-sulfonic acid was added as a fluorescent probe, and the excitation wavelength was 370 nm and the emission wavelength was 4 with a fluorometer.
Measurement was performed at 70 nm (fluorescence intensity FI), and the obtained value is shown per whey protein (mg).

Hereinafter, the present invention will be described in detail.

According to the prior art, gelation of whey protein is mainly performed by rapid polymerization between protein molecules by heat treatment or the like. Most of the gels obtained as a result are non-uniform, have poor water retention, and have the attribute of becoming cloudy, and their use as a food material gel is limited. These attributes are considered to be determined by the degree of denaturation between protein molecules, the mode, and the like.However, in the related art, it is considered that the above-described properties are expressed because the protein is thermally denatured until gel formation. Can be The present inventors have found the possibility of adjusting the gel properties by controlling the denaturation of protein molecules without being limited to thermal denaturation, and have reached the present invention.

That is, when whey protein (hereinafter referred to as WP) is limitedly denatured to form a soluble aggregate and increase the hydrophobicity of the molecular surface, the pH is then increased to a pH above the isoelectric point of WP.
It was considered that gelation having a uniform network structure would occur by adjusting and promoting hydrophobic bonding. In this way, a gel having good transparency and water retention is formed.

What is important here is the limited denatured WP
In the process of gelling, the presence of milk proteins or fats and oils
That is, it greatly contributes to the formation of the structure of the P molecule. W
It is not clear how milk proteins or fats and oils are involved in the formation of the P network structure, but it is thought that they exert a different effect than saccharides.

In order to induce gelation by adjusting the pH within the range of the isoelectric point of WP or higher, WP molecules must be sufficiently denatured and have high hydrophobicity. As a guide of the degree of hydrophobicity, 50 [FI / mg protein]
It is preferable that the number is 70 or more.

On the other hand, a soluble aggregate is formed as a result of denaturation of the WP molecule. The extent of the soluble aggregate is at least 20%, preferably at least 30%, of the total protein of WP from the aggregate having a molecular weight of 1,000,000 or more. That's enough. Where the molecular weight is 10
The reason that the molecular weight of the native WP is about tens of thousands on average is considered to be in a state of forming a gel when bound to about 1 million because the molecular weight of the native WP is about tens of thousands.
In addition, the molecular weight of the protein shows the value measured by high performance liquid chromatography (HPLC).

The degree of hydrophobicity and the state of the aggregate are guidelines for defining limited denaturation. If any of the above conditions is satisfied, it is considered that sufficient denaturation has occurred. Is done. Therefore, it is not necessary to simultaneously satisfy both conditions of the degree of hydrophobicity and the association, and the degree of denaturation can be evaluated using either one as an index. However,
Since the degree of hydrophobicity and the state of the aggregate are closely related, if one condition is satisfied, the other condition is usually satisfied.

Those having a molecular weight of 1,000,000 or more account for 20% of the whole
When the degree of hydrophobicity is 50 [FI / mg protein] or less, gelation does not occur even after subsequent pH adjustment. If the molecular weight is 1,000,000 or more, or if the hydrophobicity is 50 [FI / mg protein] or more, the subsequent p
Gelation is ensured by H adjustment. If denaturation proceeds excessively, p
Since gelation occurs without H adjustment, the solution state cannot be maintained even after denaturation, and it is necessary to appropriately select WP concentration and denaturation conditions. That is, the upper limit of the denaturation is to the extent that the WP solution maintains a liquid state, and this extent varies depending on the WP concentration and the like, and is not uniquely determined as a numerical value.

In the present invention, any commonly available WP can be used. For example, whey, such as butter and cheese, separated in the dairy manufacturing process can be used by concentrating the protein by ultrafiltration. Preferred WPs include whey protein concentrate (WPC) and whey protein isolate (WPI). These are because they have a relatively low ash content and easily form an elastic gel. Usually, whey protein concentrate has a protein content of 50% or more. Hereinafter, the amount of whey protein (WP) refers to the protein content on the analytical value. Further, β-lactoglobulin and α-lactalbumin separated from WP can be used as WP.

Next, as a means of WP modification, any method of heating, pressure, and organic solvent may be used, that is, any means of modification may be used. This is because, in the present invention, the degree of denaturation of the WP molecule is a problem, and the WP molecule is not directly gelled by the denaturation treatment.

The concentration of the WP solution to be treated is in the range of 1 to 40%, the heating temperature is 60 ° C. or more, the pressure treatment is 100 to 1000 MPa, and the concentration of the organic solvent is 10% or more. Good to do. If the WP concentration is high and the processing conditions are severe, gelation may occur during the processing. On the other hand, if the WP concentration is too low, efficiency processing cannot be performed.

The pH of the solution during the denaturation treatment does not need to be particularly adjusted, but is preferably in the range of about 6.0 to 8.0. p
If the H is low, WP coagulates and precipitates during the treatment and a smooth gel cannot be formed, and the pH becomes high.
When it is about 9.0, it becomes unacceptable in flavor as food.

The denaturation treatment does not need to be carried out in a solution state of the WP. For example, the WP may be denatured in a powder state by a pressure treatment or a method of immersion in alcohol overnight. Even when WP treated with a powder is used as a solution, it does not cause precipitation or the like, and has a gelling function similar to that of WP treated in the state of a WP solution.

Subsequently, 100 parts of this modified WP solution (hereinafter referred to as
"Parts" represents "parts by weight", and 0.1 to 200 parts of a milk protein material is added to obtain a WP liquid composition. The step of preparing this composition can be performed separately from the above-mentioned modification treatment step. That is, the WP once denatured is an irreversible change that does not return to its original state even after being left.

Examples of the protein material include milk protein materials such as casein, skim milk powder, whole milk powder, and soybean protein, and preferably milk proteins having casein as a main protein. The WP concentration in the WP liquid composition is 1 to
It may be prepared in a range of 40%. At a concentration lower than this, gelation does not occur even by pH adjustment, and at a concentration higher than this, a gel having a hard texture is obtained. Milk proteins such as casein interact with denatured whey protein, and in a solution system having a whey protein concentration of 10% or less and a milk protein concentration of 10% or less, mixing is facilitated and a smooth gel composition is obtained by adjusting the pH. To form On the other hand, in a solution system having a concentration higher than both, a milk protein such as casein comes into close contact with the denatured whey protein and forms a composition having a strong structure after pH adjustment.

On the other hand, 0.1 to 200 parts of fats and oils such as vegetable oil and animal oil are added to 100 parts of the modified WP solution and emulsified to obtain an emulsion. The WP concentration in the emulsion is preferably adjusted in the range of 1 to 40%. The fats and oils are preferably liquid because they are easy to mix, but may be solid or semi-solid at room temperature as long as they are liquid at the time of mixing the modified WP solution. The type does not matter whether it is vegetable or animal, or the type of constituent fatty acids. For example, soybean oil, corn oil, wheat germ oil,
Lard and the like can be used, but from the viewpoint of the function of forming an emulsion, vegetable oil containing a large amount of unsaturated fatty acids is preferable as the fat or oil. When fats and oils are added, emulsification with denatured whey protein is easily performed, and in a system of a solution having a whey protein concentration of 10% or less and a fat and oil concentration of 10% or less, a smooth and stable emulsion is formed by pH adjustment. The denatured whey protein has an emulsifying property and has a function of adsorbing to the oil-water interface to stabilize the emulsion. On the other hand, in the case of an emulsion solution having a concentration higher than both, the denatured whey protein adsorbed on the oil-water interface is further denatured more slowly, and gels with time-dependent increase in viscosity after pH adjustment to obtain a paste emulsion gel.

The type of the emulsion may be either W / O type or O / W type. If the amount of the fat or oil is small, the effect of the fat or oil is not exhibited, and if the amount is too large, the gel itself is difficult to be formed.

The milk protein and the fats and oils need not always be alternative, and the properties of the gel obtained by mixing may be changed. If necessary, both may be mixed.

In the subsequent step, the pH of the WP liquid composition or WP liquid emulsion is adjusted with the isoelectric point of whey protein as the lower limit. That is, when the denatured whey protein is gelled by adjusting the pH, the pH of the WP liquid composition and the emulsion is usually around neutral to weakly acidic (pH 6.5 to 7.0).
Therefore, in order to adjust the pH to a value lower than that and equal to or higher than the isoelectric point, pH 5.0 to 6.5, preferably pH 5.5 to 5.5.
Adjust the pH in the range of about 6.0. pH 5.0-6.
In the range of 5, a gel having elasticity and good transparency can be obtained. This is because the denatured whey protein has previously formed an aggregate in a limited manner. By adjusting the pH to the range of 5.0 to 6.5, the hydrophobicity is sharply increased, and the aggregate is further bound. It is considered that gelation occurs. Such gelation does not occur when an undenatured whey protein or a protein having a low degree of denaturation having a hydrophobicity of 50 [FI / mg protein] or less is used. When the pH is lowered to the isoelectric point or lower, the state becomes close to agglomeration, loses elasticity, and becomes a cloudy brittle gel.

The pH adjustment operation is performed by the WP liquid composition described above,
It can be performed separately from the operation for preparing the emulsion. That is, the WP liquid composition and the emulsion can be distributed and stored by themselves, and can be subjected to a gelling treatment as needed.

The means for adjusting the pH is not particularly limited. For example, lactic acid bacteria and acidifying agents such as GDL, low-pH milk, and acidic foods (eg, wine and vinegar) can be used.

The WP liquid composition was adjusted to pH 5.0 to 6.5.
When the pH is adjusted within the range, an elastic gel having a good mouth feel can be obtained. When a composition having a whey protein concentration of 10% or less and a milk protein concentration of 10% or less in the weight of the composition is adjusted to a pH of 5.5 to 6.5, an elastic soft gel can be obtained. That is, since the pH is 5.5 or more, it is higher than the isoelectric point of casein, has little acidity, has a texture similar to tiramisu, has a rich texture, and a fat-like texture can be obtained. Further, since the gel is soft and easily mixed uniformly with other materials, it can be used as a fat substitute or a bulking agent by adding it to dairy products such as cheese or kneading flour products such as noodles into dough.

On the other hand, a composition having a whey protein concentration and a milk protein concentration of 10% or more and 40% or less has a pH of 5.5 to 6.5.
A gel having excellent shape retention, high water retention, and high gel strength can be obtained by using the composition prepared in (1). This gel can also be added to tofu, jelly, flour products, etc. to improve shape retention and water retention. Further, when the composition has a whey protein concentration and a milk protein concentration of 40% or more, the gel has a somewhat messy texture, which is not preferable.

When the pH of the WP liquid emulsion is adjusted to the range of 5.0 to 6.5, a smooth gel can be obtained. The pH of the emulsion solution having a whey protein concentration of 10% or less and a fat or oil concentration of 10% or less is particularly adjusted to 5.5.
When adjusted to the range of ~ 6.5, the texture becomes similar to cream cheese with low acidity and tiramisu, and a gel having a rich feeling and excellent smoothness in the mouth can be obtained. This gel has particularly high water retention and does not cause water separation. Further, since the gel is soft and easily mixable with other materials, it can be mixed with other foods to give smooth texture and richness.

On the other hand, when the whey protein concentration
% To 40% emulsion solution at pH 5.5 to
When the gel is adjusted to 6.5, a gel having more excellent elasticity, shape retention and water retention can be obtained. Further, when the solution has a whey protein concentration and a fat concentration of 40% or more, emulsification becomes difficult, oil-off occurs, and a uniform gel is not obtained.

The gel obtained by adding milk proteins and fats and oils has such characteristics and excellent dispersibility, and becomes a paste as it is or by stirring. Has no adverse effect on That is, it also has heat resistance. In addition, these gels have high water retention, especially when fats and oils are added, when freezing and thawing, no water separation occurs, without adversely affecting the physical properties,
It is a gel with excellent storage properties.

The time required for gelation is about 0.2 to 2 hours at 5 to 25 ° C. The temperature during the gelling step does not need to be particularly controlled, and may be about room temperature. The higher the temperature, the easier the gelation is promoted. However, the temperature must be lower than the denaturation temperature of whey protein, and if it is too high, uneven aggregation occurs.

In the above pH adjustment treatment, the WP liquid composition and the emulsion may be brought into contact with a phase whose pH is substantially controlled. The solution may be dropped into the prepared solution (becomes a capsule-like gel), or may be mixed into the fermented product and injected. Therefore, pH adjustment treatments are extremely diverse and broad, and can be applied to foods. What is important here is that since the pH range of the pH adjustment is weakly acidic at or above the isoelectric point, the influence on the taste of the food is small, and treatment such as heating is not required during the pH adjustment.
Therefore, it is also effective as a fat substitute and as a bulking agent, a water retention agent, and a stabilizer. In this respect, the utility and practicality are extremely high as compared with the conventional whey protein gel technology. The WP liquid composition and emulsion described above contain WP as a gelling main component. In addition, gelatin and the like as gelling aids, sugars and amino acids as taste components, flavors, coloring materials Other sub-materials can be contained as needed within a range that does not substantially affect gelation.

[0043]

Embodiments of the present invention will be described below.

Test Example 1 Preparation of Denatured WP Solution Heat-denatured WPI (BIO-ISOLATES LTD. BIPRO, ash content 2% per 97% protein dry weight) was dissolved in water and 1000 g
(WP concentration 6%, pH 7). This was heated with stirring in a hot water bath, and the solution whose temperature reached a predetermined temperature (heated to the maximum temperature) and the solution held for 10 minutes (heated for 10 minutes) were cooled to 20 ° C. The molecular weight of the protein in it was determined by HPLC. Table 1 shows the results. As is clear from the table, sufficient protein denaturation did not occur at a heating temperature of 70 ° C. for about 10 minutes.

[0045]

Table 1 Relationship between heating conditions of 6% WPI solution and protein molecular weight加熱 Ultimate temperature heating 10 minutes holding heating 量 Molecular weight Molecular weight 10,000 1,000,000 or more 10,000 1,000,000 or more ───────────────────────────────── 70 ℃ 100% 0% 100% 0% 80 ℃ 70% 30% 40% 60% 90 ° C 35% 65% 0% 100% 圧 力 Pressure Denaturation A solution similar to that described above was prepared, placed in a 20 ml laminate film, set in a cold isostatic press (Mitsubishi Kogyo), pressurized to a predetermined pressure, and held for 30 minutes. The temperature was 20 ° C. The molecular weight of the protein in the treated sample was measured in the same manner as described above.
Sufficient denaturation was observed with treatment at Pa or higher.

[0046]

[Table 2] Table 2 Relationship between pressure treatment conditions and protein molecular weight of 6% WPI solution ─────────────────────── Molecular weight of 11,000,000 or more ── ───────────────────── Untreated 100% 0% 100 MPa 80% 20% 400 MPa 40% 60% 1000 MPa 0 100% ─────────ゲ ル Gelation test 10 proteins with a molecular weight of 1,000,000 or more
% To 100% samples were prepared and their gelling ability was examined. In the test for gelling ability, pH was adjusted to 6.0 using GDL as an acidic agent, left at room temperature for 2 hours after the addition of the acidic agent, and it was observed by observation whether a gel was formed. Table 3 shows the results. As is clear from the table, gelation occurred when the molecular weight was 1,000,000 or more and 20% or more.

[0047]

[Table 3] Test Example 2 Preparation of Denatured WP Solution Heat Denaturation The WP solution was treated in the same manner as in Test Example 1, and the hydrophobicity of the protein was measured. Table 4 shows the results. As is clear from the table, the hydrophobicity reached 50 [FI / mg protein] only after holding at the heating temperature of 70 ° C. for 30 minutes. At 80 ° C., heating to a maximum temperature was sufficient.

[0048]

[Table 4] Gelation test As described above, the degree of hydrophobicity is 30 to 80 [FI / mg prote
in], and their gelling ability was examined in the same manner as in Test Example 1. As a result, as shown in Table 5, gelation occurred at a hydrophobicity of 50 [FI / mg protein] or more.

[0049]

Table 5 Relationship between hydrophobicity and gelation by pH adjustment に よ る Hydrophobic Degree [FI / mg ptn.] 30 40 50 60 70 80 ──────────────────────────────── Liquid Liquid Gel Gelation Gelation Gelation ──────────────────────────────── (pH 6.0) Example 1 10% WPI Solution (protein concentration 9.5%, pH 6.8)
After heating at 80 ° C. for 30 minutes (hydrophobicity 65 FI / mg protein
in), 150 g of hardened soybean oil heated to 60 ° C. was added to 850 g of these solutions, and homogenized at a pressure of 70 kg / cm ² using a high-pressure homogenizer. 4 g of GDL was further added to the obtained emulsion (5 ° C.), homogenized with a high-pressure homogenizer, and then left at 5 ° C. for 20 hours to obtain an emulsion gel. As a control, a gel containing no hardened soybean oil was similarly prepared. The pH was adjusted to 5.6. The physical properties of the gel were measured using a rheometer as follows. Table 6 shows the properties of the gel. [Measurement of texture characteristics] Measuring equipment: Rheometer (Fudo Industry Co., Ltd.) Clearance: 5 mm Plunger diameter: 50 mm Compression speed: 2 cm / min. Number of compressions: 2 times Measurement temperature: 20 ° C. Gel strength: Maximum load (g) at the first compression [Measurement of water separation] Filter paper (Toyo Filter Paper No. 2, 5.5 cm)
The gel was placed in a Petri dish with 5 pieces (diameter), left at 20 ° C. for 3 hours, and the amount of water separation was calculated from the amount of water absorbed by the filter paper.

Amount of water separation (%) = (weight of water absorbed by filter paper / weight of gel) × 100

[0051]

[Table 6] Table 6 Properties of gel ────────────────────────── Soybean oil not added 無──────────────── No syneresis 20% syneresis Gel strength [g / cm ² ] 450 700 Brittleness None Yes Good texture Mouth good Slightly smooth Slightly thick Thick appearance Appearance White cloudy Gel properties Paste kneading not possible kneading possible heat resistance good none ────────────────────────── Evaluation criteria for the following evaluation items in the table Is as follows. -Brittleness: "No" indicates that the gel does not crack in the texture measurement, and "Yes" indicates that the crack has occurred.-Heat resistance: Does not cause the brittleness of the gel even at 80 ° C for 20 minutes. "Good", gel brittleness "none" ・ Gel properties: extensible at room temperature, paste-like "kneadable", non-extensible at room temperature "kneadable" As shown in Table 6, the addition of soybean oil gave a white gel having good water retention, smooth mouthfeel, good mouthfeel, but rich texture. It was also flexible and had good heat resistance.

Example 2 A 10% WPI solution (protein concentration: 9.5%) was added at 20 ° C.
A pressure treatment of 600 MPa was performed for 0 minute (molecular weight 10
70,000 or more). Thereafter, 50 g or 150 g of casein was added to 1000 g of the solution, and GD was further added.
4 g of L was added and left at 5 ° C. for 20 hours to obtain a gel.
As a control, a gel without addition of casein was similarly prepared. The pH was adjusted to 5.6, and the physical properties of the gel were measured using a rheometer.

[0053]

Table 7 Table 7 Properties of the gels {no addition casein casein 50g 100g}離 Water separation 15% Water separation None None Gel strength [g / cm ² ] 650 500 750 Fragility Yes No No Texture Good Meal Good mouthfeel Good mouthfeel Smooth smooth Smooth Appearance Cloudy Transparent Transparent Gel-like Kneading not possible Paste-like Kneading possible after stirring Kneading possible Heat resistance None Good Good ────────よ り From Table 7, the casein-added product has excellent water retention, is smooth and easy to drink, and has heat resistance. There was also a clear gel. In the case of 50 g of casein, the paste was in the form of a paste, and in the case of 100 g of casein, the paste had a shape-retaining property. However, after stirring, the paste became a uniform paste until kneading became possible. On the other hand, without casein, only a brittle gel was obtained.

Example 3 A 5% WPI solution (protein concentration: 4.8%, pH: 6.8) was subjected to pressure treatment at 20 ° C. for 30 minutes at 600 MPa (70% for a molecular weight of 1,000,000 or more). Then this solution 10
50 g of powdered powder (35% of protein) was added to 00 g, and after dissolution, this solution was dropped (about 300 mg per drop) into an acidic solution of pH 5.5 to obtain a capsule-like gel. As a control, a gel to which no dedusting was added was similarly prepared. Comparing the capsule-like gelled product, in the system to which the powder was added, the gel film forming the capsule was elastic and strong. On the other hand, in the system to which no powdering was added, the gel film forming the capsule was brittle and easily collapsed.

Example 4 A 9% WPC solution (protein concentration: 6.8%, pH: 6.8) was heated at 85 ° C. for 30 minutes, and then this solution (hydrophobicity: 70 FI /
To 1000 g of each (mg protein), 60 g and 120 g of butter oil heated to 60 ° C. were mixed and homogenized using a high-pressure homogenizer at a pressure of 80 kg / cm ² . Then, at room temperature, p
1000 g of milk in which H was adjusted to 5.5 with GDL was mixed and emulsified, and allowed to stand for 1 hour to obtain a gel. As a control, a gel to which no butter oil was added was similarly prepared. Table 8 shows the results.

[0056]

Table 8 Properties of gel No additive Butter oil Butter oil 60 g 120 g離 Water separation 20% Water separation None None Gel strength [g / cm ² ] 450 300 350 Fragility Yes No No Texture Slightly Mealy Good mouthfeel Good mouthfeel Smooth Smooth Smooth Gel properties Not kneadable Paste Kneadable after agitation Kneadable Kneadable Heat resistance None Good Good ────────────ゲ ル As shown in Table 8, the gel to which butter oil was added had excellent water retention, was smooth and mellow, and had good heat resistance. Was also excellent. The gel of 60 g of butter oil is a paste, 12 g.
The sample of 0 g was a solid having shape-retaining properties, but after stirring, the paste became uniform enough to be kneaded. On the other hand, without addition, only a brittle gel was obtained.

Example 5 A 9% WPC solution (protein concentration: 6.8%, pH: 6.8) was heated at 85 ° C. for 30 minutes, and 60 g of dedusting was added to 850 g of this solution (molecular weight: 1,000,000 or more, 65%). And dissolved. This solution was added to the cheese and utilized as a bulking agent and fat substitute. When the cheese is heated and emulsified, cheese 1
400, 1000, 160
0 g was added to emulsify. This allows the solution to have a pH
5.8. As a control, a solution to which no flour was added was added to the cheese and emulsified. In the system to which the powder was added, uniform emulsification was performed, and the resulting cheese was smooth and had a good texture as shown in Table 9. On the other hand, in the system without the addition of powdering, the solution could not be uniformly emulsified with the cheese, and the resulting cheese had a feeling of milky.

[0058]

[Table 9] Table 9 Properties of cheese (addition of flour) ───────────────────────────────── Milk protein Milk Protein Milk protein solution 400 g Solution 1000 g Solution 1600 g ───────────────────────────────── Tissue Hard Soft Elastic Strong Cream cheese-like Gel-like Texture Good mouthfeel Good mouthfeel Good mouthfeel Smooth Smooth Smooth Rich rich Rich rich rich 感───────────

[0059]

According to the present invention, a gel having unique characteristics can be obtained by utilizing a specific effect which is obtained when milk protein and fats and oils are mixed, which cannot be obtained by using whey protein alone. Addition of milk protein gives a gel with a less fatty taste and a rich texture with a fat-like texture. In addition, since the gel is soft and easily mixed with other materials uniformly, it can be used as a fat substitute or a bulking agent, and when added to food, can improve shape retention and water retention. With the addition of fats and oils, a gel with less sourness and richness and excellent smoothness in the mouth can be obtained. This gel has particularly high water retention and does not cause water separation. In addition, since the gel is soft and easily mixed with other materials evenly, it can be mixed with other foods to give a smooth texture and richness. The gel obtained by adding milk protein and fats and oils has such characteristics, and also has excellent dispersibility, and can be used as is or by stirring to form a paste. Has no effect. That is, it also has heat resistance. In addition, these gels have high water retention properties, and particularly when added with fats and oils, do not cause water separation during freezing and thawing, do not adversely affect the physical properties, and have excellent preservability.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-79940 (JP, A) JP-A-56-26159 (JP, A) JP-A-2-145175 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) A23J 3/08 A23C 19/09 A23C 21/04-21/06 A23J 3/00

Claims (3)

(57) [Claims] 1. A whey protein solution having a degree of hydrophobicity of 50 [FI / mg protein] or more, or 20% or more of the total protein is composed of a whey protein aggregate having a molecular weight of 1,000,000 or more per 100 parts by weight of a whey protein solution. , Other protein materials 0.1-2
P of a whey protein liquid composition containing 100 parts by weight
H should be reduced with the isoelectric point of whey protein as the lower limit.
And a gel substitute for fat obtained by 2. A whey protein solution having a degree of hydrophobicity of 50 [FI / mg protein] or more or 20% or more of the total protein is composed of a whey protein aggregate having a molecular weight of 1,000,000 or more per 100 parts by weight of a whey protein solution. , pH of whey protein liquid emulsion comprising fats and oils 0.1 to 200 parts by weight
Lowering the isoelectric point of whey protein as a lower limit
And a fat substitute gel obtained by the above method. 3. The gel-substituted fat substitute according to claim 1 or 2.
Food containing.