JPH11318358A - Modification of gelatin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a modified gelatin capable of retaining a stable emulsified state even when heat-treated. SOLUTION: Gelatin and saccharides added to water are preheated and dissolved therein and the resultant solution is then heat-treated at 100-130 deg.C. In this case, the formulating ratio of the gelatin to the saccharides is (1:1) to (100:1) expressed in terms of weigh ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for modifying gelatin, and more particularly, to a method for modifying gelatin in which gelatin and saccharides are preliminarily heated and dissolved, followed by heat treatment.

[0002]

2. Description of the Related Art Gelatin is well known as a material having food functions such as gel-forming properties and emulsifying properties, and is used in various products by utilizing those functions. For example, a solid mayonnaise which is solid at room temperature (Japanese Patent Laid-Open No.
48903) and the production of mayonnaise that is stable at a low temperature (JP-A-49-26439). However, since gelatin is inherently heat-soluble, about 50%
It has the property of melting at a temperature of not less than ° C. For this reason,
In the case of emulsified foods such as mayonnaise using gelatin, when heated, the viscosity sharply decreases, and there is a problem that it is extremely difficult to maintain an emulsified state.

[0003]

As a method for modifying the functionality of a protein, Japanese Patent Application Laid-Open (JP-A) No. 3-215498 has been proposed.
As disclosed in JP-A Nos. 9-107886 and 9-107886, a protein and a saccharide are mixed under low water content,
There is a method of reacting at 0 ° C. or lower for several days to several weeks. However, these methods require a long time for work, and also have problems in terms of cost, equipment and other economical aspects, and have not been put to practical use at present.

Accordingly, it is an object of the present invention to solve the above-mentioned various problems and to provide a modified gelatin which can maintain a stable emulsified state even after heat treatment. The present inventors have conducted intensive studies and found that, after preliminarily heating and dissolving gelatin and saccharides added to water, a heat treatment is performed at a predetermined temperature to maintain a stable emulsified state against heating. Was found, and the present invention was completed based on such findings.

[0005]

The present invention according to claim 1 is characterized in that gelatin and saccharide added to water are preheated and dissolved, and then heat-treated at 100 to 130 ° C. This is a method for reforming. The present invention according to claim 2 is the method according to claim 1, wherein the mixing ratio of gelatin and saccharide is the former: the latter = 1: 1 to 100: 1 by weight.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. First, the kind of gelatin used in the present invention may be either acid-treated gelatin or alkali-treated gelatin, and those having a jelly strength of about 70 to 250, preferably 80 to 150 are suitably used. If the jelly strength is less than 70, the original functionality of gelatin is reduced, so that the functional modification cannot be expected even if the treatment of the present invention is performed. on the other hand,
If it exceeds 250, there will be disadvantages such as poor solubility and too high viscosity.

Various saccharides can be used as the saccharide used in the present invention. For example, monosaccharides such as xylose, glucose and fructose, disaccharides such as maltose, lactose and sucrose, guar gum decomposed products and tamarind gum And the like, and one or more of them can be appropriately selected and used.

[0008] The reforming method of the present invention can be carried out according to the following procedure. First, gelatin and sugar are added to water. At this time, the mixing ratio of the two is the former: the latter = 1: 1 by weight ratio.
１００100: 1, preferably 1: 1 to 50: 1. If the blending ratio is less than 1: 1 by weight, the effect of modifying gelatin cannot be expected, while if it exceeds 100: 1,
The effect of modifying gelatin is insufficient, which is not preferable. The amount of the mixture of gelatin and saccharide added to water is suitably from 5 to 50% by weight, and preferably from 10 to 35% by weight. If the amount is out of this range, the handleability becomes inconvenient and economically unfavorable. The mixture is then preheated to dissolve it in water. The preheating temperature is usually 40 to 80
° C, preferably 50-60 ° C. Since the pH of the aqueous solution in which gelatin and saccharides are dissolved is preferably about 5 to 8, it is adjusted with an alkali such as sodium hydroxide as needed. In the acidic region where the pH is less than 5, the effect of the modification treatment is not sufficient. On the other hand, when the pH exceeds 8, the liquid after treatment is undesirably browned or imparts an unpleasant taste.

Thereafter, the above solution is subjected to a heat treatment to modify the gelatin. The heating temperature at this time is 100 to 13
0 ° C is appropriate, and 110 to 120 ° C is more preferable.
Heat treatment is performed at this temperature for 1 hour or more, usually 1 to 6 hours, preferably 2 to 4 hours. Heat treatment temperature is 100 ° C
Therefore, a heat and pressure resistant device such as an autoclave should be selected as the device used for this treatment. If the heating temperature is lower than 100 ° C., the effect of modifying gelatin is poor. If the heating temperature is higher than 130 ° C., the treated liquid may be remarkably browned or have an unpleasant taste, which is not preferable. On the other hand, if the treatment time is less than 1 hour, the effect of modifying gelatin is insufficient, which is not preferable. The solution after the heat treatment is left for cooling or cooled by an appropriate means and then used as it is or as a powder by applying means such as freeze-drying for various uses.

[0010] The modified gelatin obtained by the above method retains its original functions such as gel-forming property and emulsifying property, and is completely different in heat stability from untreated gelatin. Even when heated to the above temperature, a stable emulsified state is maintained. Although the mechanism by which gelatin is modified has not been fully elucidated, it is speculated that gelatin and saccharides may have formed a substance having a complicated structure by an aminocarbonyl reaction.

There is no special condition for the method of use and use of this modified gelatin, and it is the same as conventional gelatin, and can be used in the fields where the above functions can be exhibited, such as dressings, mayonnaise, spreads and the like. It can be used for various kinds of emulsified foods such as.

[0012]

EXAMPLES The present invention will be described below in more detail with reference to examples and the like, but the present invention is not limited by these examples. Examples 1 to 5 Gelatin (jelly strength: 100) and various sugars were added to water so as to have the mixing ratios shown in Table 1 and dissolved by heating at 50 ° C. The obtained solution was subjected to heat treatment at a predetermined temperature and time in a sterilizing autoclave (Autoclave KT-40, manufactured by Shimadzu Corporation) to obtain 2 kg of a modified gelatin solution. Table 1 shows the conditions.

[0013]

[Table 1]

Comparative Examples 1 to 4 2 kg of a modified gelatin solution was obtained in the same manner as in Example 1 except that the mixing ratio of the raw material gelatin and the saccharide and the conditions of the heat treatment were changed. The conditions at this time are shown in Table 1.

Reference Example 1 After the modified gelatin solutions prepared in Examples 1 to 5 and Comparative Examples 1 to 4 were cooled to room temperature, oil-in-water emulsions were prepared according to the formulations shown in Table 2. That is, a predetermined amount of rapeseed oil is added to an aqueous phase obtained by mixing and dissolving a predetermined amount of a gelatin solution, vinegar (10% acetic acid solution), salt and water, and a low-speed 3 min. Pre-emulsified. Then, a colloid mill (clearance 7/100)
Finish emulsification was performed at 0 inch at a rotation speed of 3000 rpm to obtain an oil-in-water emulsion.

[0016]

[Table 2]

Next, the heat resistance of this oil-in-water emulsion was evaluated. The evaluation was performed by the following method. 100 g of the oil-in-water emulsion was filled in a heat-resistant retort pouch, and heat-treated at 120 ° C. for 30 minutes in an autoclave, and the appearance was visually observed. Those with no oil separation were rated "good", those with partial separation were "somewhat good", and those with clear oil separation were "poor". The results are shown in Table 3.

[0018]

[Table 3]

As is evident from the table, the oil-in-water emulsion prepared using the modified gelatin obtained according to the method of the present invention has no or little degree of partial separation of the oil component. High heat resistance. On the other hand, in the oil-in-water emulsion prepared using the gelatin obtained in Comparative Example, clear separation of the oil component occurred, and the heat resistance was poor.

[0020]

According to the method of the present invention, a modified gelatin which maintains an emulsified state stable to heating can be obtained. Therefore, this modified gelatin can be suitably used for emulsified foods and the like that require a heat treatment step.

Claims (2)

[Claims] 1. A method for modifying gelatin, comprising preliminarily heating and dissolving gelatin and saccharide added to water, followed by heat treatment at 100 to 130 ° C. 2. The method according to claim 1, wherein the mixing ratio of the gelatin and the saccharide is the former: the latter = 1: 1 to 100: 1 by weight.