JPH0678693A - Oil-in-water type emulsion - Google Patents

Abstract

PURPOSE:To provide the subject emulsion comprising york treated with transglutaminase, improved in the emulsifying function of the york as an emulsifier, excellent in emulsion stability, reduced in the smell of the york, and useful for foods such as mayonnaises and dressings. CONSTITUTION:A prescribed amount of a transglutaminase originated from a microorganism (e.g. Streptoverticilliium.mobaraense IFO 13819) belonging to the genus Streptoverticilliium is dissolved in a small volume of water. The enzyme solution is added to york and subsequently heated at 50 deg.C for 30min to modify the york, thereby providing an oil-in-water type emulsifier which is improved in the emulsifying functions of the york as an emulsifier, has excellent emulsion stability, and is reduced in the smell of the york. The york emulsifier is mixed with aqueous phase raw materials, oily phase raw materials, etc., and subsequently subjected to an emulsifying treatment to provide the oil-in-water type emulsion food such as mayonnaise, various kinds of dressings or Sandwich spread.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-in-water emulsifier consisting of egg yolk treated with transglutaminase and an oil-in-water emulsion food using such an emulsifier.

[0002]

BACKGROUND OF THE INVENTION Egg yolk is well known as an oil-in-water emulsifier, and various oil-in-water emulsion foods containing this as an emulsifier are known, including mayonnaise, various dressings and sandwich spreads.

The stability of these foods against heat and pH is
Again, it depends on the stability of the emulsion itself.
These foods are often low pH foods, and the emulsion is unstable as it is. So if you can stabilize the emulsion by some technique,
Stabilization of these emulsion foods can be solved. One of the general efforts up to now for the problem of stabilization has been to reduce the size of oil droplets, that is, to increase the emulsification, by devising the emulsifying conditions such as an emulsifier and an emulsifying machine. . The other is polysaccharides, sugars such as gums,
Using protein modifiers such as egg white and casein,
It was to stabilize the emulsion.

Under such a technical background, egg yolk is one of the excellent natural protein emulsifiers. However, this egg yolk has a characteristic odor. In particular, oil-in-water emulsion foods often do not like the yolk odor because of the balance in flavor. In this case, if the amount of egg yolk added is reduced in order to suppress the yolk odor, there arises a defect in properties such as a reduction in emulsion stability.

Therefore, in the present situation, a relatively small amount of egg yolk having a strong emulsifying property is desired in the food industry. It should be noted that such a modified egg yolk can be said to be economically favorable.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems of egg yolk, and its object is to ensure emulsion stability with a relatively small amount of yolk. And to obtain an oil-in-water emulsion having a weak odor of egg yolk.

[0007]

Means for Solving the Problems The present inventor has conducted extensive studies to solve the above problems, and as a result, modified egg yolk modified by acting transglutaminase exhibits high emulsification and emulsion stability. And a food composition comprising an oil-in-water emulsion obtained by emulsifying the modified egg yolk as an emulsifier has excellent emulsion stability and reduced yolk odor, which cannot be obtained by conventional techniques. They found that they have quality and completed the present invention.

That is, the present invention relates to an in-water emulsifier consisting of egg yolk treated with transglutaminase, and an oil-in-water emulsion food product using such an emulsifier.

The present invention will be described in detail below.

The egg yolk referred to in the present invention may be not only raw egg yolk obtained by separating egg white from egg yolk, but also egg yolk liquid obtained by rehydrating whole egg or dried egg yolk, that is, it is used as an oil-in-water emulsifier. The form does not matter as long as it can be obtained.

The function of egg yolk as an emulsifying agent is improved by the action of transglutaminase because ε- (γ-Glu) Ly between protein molecules of transglutaminase or between glutamine and lysine within the molecule.
It is considered that the protein in the egg yolk is modified by the s-crosslinking polymerizing action.

The transcurtaminase used in the present invention is derived from mammals (see Japanese Patent Publication No. 1-50382), from fish (see page 180 of the Autumn Meeting of the Fisheries Society of Japan in 1991), plants It is known that it is derived from a microorganism, derived from a microorganism (see Japanese Patent Laid-Open No. 1-27471), genetically modified (see Japanese Laid-Open Patent Publication No. 1-300889), and the like, and it can be used regardless of its origin.

The amount of transglutaminase to be added to act on egg yolk is 0.1 per 1 g of egg yolk protein.
About a unit, preferably 0.3 unit or more is necessary. When the amount added is about 0.1 unit or less, there is almost no difference in emulsion stability from those without this enzyme. On the other hand, the upper limit of the amount added is not particularly limited in terms of the quality of the egg yolk as an emulsifier, but considering that the effect of the addition is in equilibrium at about 50 units or more, it can be said that it is about 50 units. . Finally, transglutaminase is generally used in the range of about 0.1 to about 50 units, preferably about 0.3 to about 50 units, per g of egg yolk protein. Incidentally, the effect of addition is judged by whether or not the amount of egg yolk used as an emulsifier can be reduced. That is, if the egg yolk not acting on transglutaminase is used as an emulsifier, the emulsion stability is smaller, and if the egg yolk reacted with transglutaminase is used as an emulsifier, the addition effect is Yes, and

The activity unit of transglutaminase referred to in the present invention is measured and defined as follows. That is, benzyloxycarbonyl-L-glutaminylglycine and hydroxylamine are reacted as substrates, the formed hydroxamic acid is allowed to form an iron complex in the presence of trichloroacetic acid, and the absorbance at 525 nm is measured to determine the amount of hydroxamic acid. Is calculated from the calibration curve to calculate the activity (see Japanese Patent Laid-Open No. 1-27471).

A specific method for causing transglutaminase to act on egg yolk is as follows, for example. That is, pH 5
Under the condition of about -9 (pH range in which enzymatic activity of transglutaminase is expressed), transglutaminase dissolved in a small amount of water is added to raw egg yolk, and this mixture is added at about 30 ° C.
The heat treatment is performed for about 25 minutes or more. The heat treatment temperature and heat treatment time are determined in relation to the heat denaturation of egg yolk and the inactivation of transglutaminase. For example, the emulsification performance of egg yolk that has undergone excessive heat denaturation decreases conversely, and in the production of an oil-in-water emulsion food product using this as an emulsifier, phase inversion occurs during emulsification, or the obtained oil-in-water emulsion Problems such as deterioration of the emulsified state occur. Therefore, for example, the heat treatment temperature of egg yolk is usually preferably 30 ° C. or higher and around 70 ° C. or lower, and the heat treatment time is usually preferably 25 minutes or longer.

Next, a method for producing an oil-in-water emulsion food using the egg yolk modified as described above as an emulsifier will be described.

The oil-in-water emulsion food referred to in the present invention is one in which egg yolk is the only emulsifier or one of the emulsifiers, and examples thereof include mayonnaise, dressing, and sandwich spread. In addition to such final products, oil-in-water emulsion foods as various intermediate products (food materials) can also be mentioned.

There is no particular limitation on the method for producing such an emulsion food in water, and any conventional method can be used except that the egg yolk modified by the action of transglutaminase is used as the egg yolk as an emulsifier.

For example, transglutaminase is added to egg yolk and the heat treatment as described above is performed. Then, an aqueous phase raw material is added and mixed and dissolved, and an oil phase raw material is further added to emulsify.
For egg yolk, after mixing the aqueous phase raw materials in the range of pH 5 to 9, transglutaminase is added and heat treatment is performed under the above conditions to modify the egg yolk, and then the acidic raw materials and oil phase raw materials are mixed and dissolved. , Finish with a colloid mill and emulsify.
Incidentally, the oil-in-water emulsifier consisting of egg yolk treated with transglutaminase also includes those which are generated in situ in the system during the production process of oil-in-water emulsion food.

In the oil-in-water emulsion food of the present invention, the raw material constituting the water phase is appropriately selected from water, egg yolk, vinegar, water-soluble seasonings, spices, sweeteners, colorants, etc. The type and amount added are determined according to the application.

On the other hand, the oil phase raw material is animal and vegetable oils and fats which are liquid at room temperature, and salad oil and the like are particularly suitable. In addition to these, oil-soluble flavoring agents, spices, coloring agents and the like are appropriately added.

The ratio of the oil phase in the emulsion is 50-
About 85% is appropriate. If it is less than about 50%, the viscosity becomes insufficient and the current state of creaming occurs, resulting in separation water in the lower phase, which is not preferable. On the contrary, if it exceeds about 85%,
It is not preferable because phase inversion occurs during emulsification and the emulsified state of the obtained oil-in-water emulsion food is deteriorated.

As described above, the emulsion of the low-pH oil-in-water emulsion food is unstable, but when the modified egg yolk of the present invention is used as an emulsifier, it has a low pH, for example, a pH of 6 or less in water. The destabilization of the emulsion of the oil-based emulsion food is prevented.

[0024]

The present invention will be described in more detail with reference to the following examples. Of course, this does not limit the technical scope of the present invention.

Example 1 Based on the blending amounts shown in Table 1 below, each blending material (raw material) was prepared so that the finally obtained oil-in-water emulsion composition would be 3 kg. A microorganism belonging to the main bacterium Streptoverticillium (Streptroverticillium mobara
ense IFO 13819) origin transglutaminase (specific activity 1.04 units / mg) was dissolved by adding a small amount of water, and this enzyme solution was added to egg yolk and mixed. As shown in Table 1, the predetermined amount of the enzyme is 0 unit (sample 1A), 0.3 unit (sample 1B), 0.6 unit (sample 1C) and 3 units (sample 1D) per 1g of egg yolk protein. did. The egg yolk was modified by heat-treating them at 50 ° C for 30 minutes. After mixing the aqueous phase raw materials, soybean oil was added and pre-emulsified for about 2 minutes with a propeller mixer. Furthermore, finish emulsification was performed with a colloid mill to obtain an emulsion composition.

The results of evaluating the characteristics of the obtained emulsion composition are shown in Table 3 below.

[0027]

[Table 1]

Example 2 According to the formulation of Sample 1D shown in Example 1, transglutaminase was added to egg yolk in an amount of 3 per 1 g of egg yolk protein.
After adding the unit, the egg yolk was subjected to a modified heat treatment under the conditions shown in Table 2 below. Next, after mixing the aqueous phase raw materials, in the same manner as in Example 1, each emulsion composition sample 2A, 2
B and 2C were obtained.

The results of evaluating the physical properties of the obtained emulsion composition are also shown in Table 3.

[0030]

[Table 2]

[0031]

[Table 3]

In Table 3, the average particle diameter was measured by a Coulter counter manufactured by Nikkaki Co., the emulsion stability was evaluated visually by the emulsion state on the emulsion surface, and the egg yolk odor of the emulsion was refined. Each was performed by a sensory test by a panel.

[0033]

EFFECTS OF THE INVENTION By applying transglutaminase to egg yolk to modify it, an egg yolk emulsifier having excellent emulsifying property and emulsion stability can be provided. In addition, such an egg yolk emulsifier is added with a water phase raw material and an oil phase raw material and then emulsified to easily provide an oil-in-water emulsion food such as mayonnaise with improved emulsion stability and egg yolk odor. became. In addition, it will contribute to the expansion of the range of utilization of egg yolk in emulsion foods.

Claims (3)

[Claims] 1. An oil-in-water emulsifier consisting of egg yolk treated with transglutaminase. 2. An oil-in-water emulsion food product using an effective amount of the oil-in-water emulsifier according to claim 1 as an emulsifier. 3. The oil-in-water emulsion food according to claim 2, which has a pH of 6 or less.