HK1178392B - Method for manufacturing gelatinous food product - Google Patents

Abstract

The present invention addresses the problem of providing a method for manufacturing a gelatinous food product, said method being capable of inhibiting the proliferation of microorganisms in said gelatinous food product during a constant-temperature process. The present invention pertains to a method for manufacturing a gelatinous food product, said method being characterized by the adjustment of the water activity of a mix during a constant-temperature process performed at a temperature lower than a sterilization temperature and higher than a freezing temperature.

Description

Method for producing gel food

Technical Field

The present invention relates to a method for producing a gel-like food which can be sterilized effectively.

Background

In the production of a gelled food such as pudding, raw materials such as a dairy product, raw water, and a gelling agent are mixed, homogenized while heating, and the mixture is prepared. Then, the mixture is sterilized, added to a container, cooled, and gelled by the action of a gelling agent, a thickener, or the like.

Sterilization of the mixture is generally performed by heat treatment at high temperature, and by this heat treatment, salmonella, coliform bacteria, and the like, which cause food hygiene problems, can be killed. However, there is a high possibility that various bacteria (for example, spore bacteria having high heat resistance) affecting the product quality remain, and it is difficult to completely sterilize them.

In recent years, puddings have been produced using a raw material containing bacteria that cannot be completely sterilized by a sterilization step of a general heat treatment, and a method for suppressing the growth of bacteria having high heat resistance when producing such puddings has been studied. For example, a method for producing vegetable pudding by heat-sterilizing soil bacteria using a direct heating sterilizer with a vacuum chamber has been studied (patent document 1); and a method for producing cocoa pudding, which improves the bactericidal activity or bacteriostatic activity of spore bacteria in cocoa powder by using a specific emulsifier (patent document 2); and a method for producing chocolate pudding, in which the bactericidal activity or bacteriostatic activity of spore bacteria in chocolate is improved by using a specific emulsifier (patent document 3). However, these methods require a special apparatus and the addition of an emulsifier or the like which affects the flavor of the final product, and thus gel-like foods are not necessarily produced optimally.

Patent document 1: japanese laid-open patent publication No. 2004-166607

Patent document 2: japanese unexamined patent application publication No. 2010-075158

Patent document 2: japanese unexamined patent application publication No. 2010-075159

The present inventors have directly faced the problem that the quality of a product cannot be homogenized due to the proliferation of spore bacteria or the like in the production of a gel-like food, which contains almost no bacteria as raw materials, despite the fact that the product is produced by ordinary production, and for example, in the production of a commercial (large-scale) gel-like food, in the step of filling a mixture (preparation liquid) subjected to heat sterilization into a container, the product is kept for a long time in a high-temperature state without causing gelation and thickening in order to continue the work of filling the mixture into the container from a large-volume storage tank, and the proliferation of spore bacteria is allowed during such a time, thereby deteriorating the quality of the product.

Disclosure of Invention

Accordingly, an object of the present invention is to provide a method for reasonably suppressing the growth of undesired bacteria in the production process of a gel-like food by solving the above-mentioned novel problems.

The present inventors have made extensive studies to solve the above-mentioned problems, and have focused attention on the relationship between the water activity of a mixture and the proliferation of undesired bacteria in a gel-like product production process, particularly in a constant temperature step in which the mixture is kept at a high temperature in a storage tank for a long time without causing gelation and thickening, and have found that the proliferation of undesired bacteria can be suppressed by controlling the water activity of the mixture in the constant temperature step to a predetermined value, and have completed the present invention through further studies.

That is, the present invention relates to the following method for producing a gel-like food.

[1] A method for producing a gelatinous food product, comprising:

(1) a blending process of blending the mixture;

(2) a heat sterilization step of heat sterilizing the mixture;

(3) a constant temperature step of maintaining the mixture at a temperature lower than the sterilization temperature and higher than the solidification temperature, following the heat sterilization step;

wherein the manufacturing method comprises adjusting the water activity of the mixture in the constant temperature process.

[2] The production method according to [1], wherein the water activity is adjusted by blending the mixture in the compounding step.

[3] The production method according to [1] or [2], wherein the water activity of the mixture in the constant temperature step is adjusted to 0.90 to 0.98.

[4] The production method according to any one of [1] to [3], wherein a heat sterilization step of performing a treatment at a temperature of 95 ℃ or higher is included before the constant temperature step.

[5] The production method according to any one of [1] to [4], wherein the temperature of the constant temperature step is 40 to 65 ℃.

[6] The production method according to any one of [1] to [5], wherein the mixture contains a starch syrup, and the water activity of the mixture is adjusted by adjusting the content of the starch syrup.

[7] The process according to item [6], wherein the mixture contains 3 to 10% by weight of the starch syrup.

[8] The production method according to [6] or [7], wherein the weight ratio of the starch syrup to the raw material water in the mixture is from 0.035:1 to 0.15: 1.

[9] The production method according to any one of [1] to [5], wherein the mixture contains granulated sugar, and the water activity of the mixture is adjusted by adjusting the content of the granulated sugar.

[10] The production method according to [9], wherein the mixture contains 8 to 15 wt% of granulated sugar.

[11] The production method according to [9] or [10], wherein the weight ratio of the granulated sugar to the raw material water in the mixture is 0.1: 1 to 0.25: 1.

[12] The production method according to any one of [1] to [11], wherein the gel-like food is a soft cake.

[13] The method according to any one of [1] to [12], wherein the gel-like food contains a raw material derived from an egg and/or a milk.

[14] The method according to [13], wherein the gelatinous food is pudding or milk pudding.

[15] The production method according to any one of [1] to [14], wherein the proliferation of bacteria in the constant temperature step is suppressed by adjusting the water activity of the mixture.

[16] The production process according to [15], wherein the bacterium is a bacterium belonging to the genus Bacillus.

According to the present invention, in the method for producing a gel-like food such as pudding, the water activity is adjusted, whereby the growth of undesired bacteria, particularly spore bacteria resistant to a high temperature state, in the production stage can be suppressed without deteriorating the flavor of the raw material. That is, since it has not been studied at all in the past, it is possible to suppress the growth of bacteria such as spore bacteria by suppressing the water activity at the stage of food production, and therefore it is not necessary to control the water activity at the stage of the final product. In order to reduce the water activity in the stage of the final product to such an extent that the proliferation of bacteria is inhibited, there is a fear that the flavor and the taste (texture) of the final product and the like are sacrificed, but according to the present invention, there is no need to pay attention to the water activity of the final product, that is, the degree of freedom to bring the water activity of the final product to a desired value is maintained from the viewpoint of the flavor and the taste, while the deterioration of the flavor and the quality can be prevented and inhibited by controlling the proliferation of bacteria in the stage of the food production. In addition, in the present invention, no special equipment is required.

In addition, in the case of filling the container from a large-capacity storage tank, in the case of a constant temperature process requiring a relatively long time such as a case where preparation of the container takes a relatively long time, for example, when the sterilized mixture is held at a high temperature (for example, 75 to 95 ℃), deterioration of flavor becomes remarkable, while when the sterilized mixture is held at a low temperature (for example, 5 to 10 ℃), gelation (solidification) or thickening occurs at this stage because a gelling agent or a thickening agent is contained in the mixture, and further, heating is required for filling the mixture into the container again, which is also a cause of deterioration of flavor, but according to the method of the present invention, such a problem of sterilization and a problem of deterioration of flavor are not caused, and a gel-like food such as pudding can be continuously produced. Further, in the case of using an emulsifier (for example, patent documents 2 and 3), it is necessary to add an emulsifier at a concentration that inhibits the proliferation of heat-resistant bacteria, which is considered to affect the flavor of the final product, and according to the present invention, the emulsifier is not necessary and the final product of a desired flavor can be completed.

Detailed Description

The method for producing a gel-like food of the present invention is characterized in that the water activity in the constant temperature step is adjusted in the conventional production step of a gel-like food. That is, after the mixture is blended by a conventional method, the mixture is heat-sterilized, the temperature is lowered as necessary, and then the mixture is filled into a container and cooled to be gelled and thickened, thereby producing a gelled food.

The operation of adjusting the water activity of the mixture may be performed in any one of (stages of) the compounding step, the heat sterilization step, and the constant temperature step.

The constant temperature step requires a long time due to the size (capacity) of the storage tank actually used, the time (required time) for preparing the container for filling the product, and the like, and the necessity of adjusting the water activity is high when the time is 2 to 24 hours, further 3 to 18 hours, and particularly 4 to 15 hours or so in relation to the spore bacteria.

In the present invention, the "gel-like food" refers to a food which is gelled and solidified by the action of a gelling agent, and examples thereof include soft cake products (seed products) such as pudding, mousse, custard (ババロア), jelly, almond curd, and lamb jelly, and tofu and konjak. In addition, soft confectionery is defined as "containing 40% or more of water after the preparation (but containing 30% or more of water after the preparation in the case of using fillings, cream, jam, agar or the like)" in the hygienic standards of western confectionery and japanese confectionery, and the gel-like food according to the present invention includes these substances.

In the present invention, "mixture" means a mixture of raw materials. The raw material to be actually used is not particularly limited as long as it is a raw material generally used for food, and for example, a dairy product, eggs, a sugar, raw water, or the like may be used as a main raw material.

In the present invention, the "blending step" is a step of selecting the kind and the amount of a raw material and adjusting the selected raw material to blend (mix) a mixture.

In the present invention, the water activity is preferably 0.98 or less from the viewpoint of suppressing bacterial growth. From the viewpoint of maintaining the texture of the gel-like food, the water activity is desirably 0.90 or more, preferably 0.95 or more, and more preferably 0.97 or more. The adjustment of the water activity in the constant temperature step can be carried out as appropriate, and for example, the water activity of the mixture can be adjusted in the step of compounding the mixture, and the water activity of the mixture in the constant temperature step can be adjusted by adjusting the kind, the ratio, and the water content of the raw materials of the mixture.

The water activity of the mixture in the constant temperature step may be adjusted, for example, by adjusting the water content of the mixture by diluting and concentrating the mixture in water after heat sterilization, or by adding a substance of the same type as or different from the raw material which is separately sterilized, or the like.

The dairy product is milk, whole milk concentrate, whole milk powder, skim milk concentrate, skim milk powder, butter, cheese, whipped cream, condensed milk without sugar, condensed milk with sugar, buttermilk oil, buttermilk powder, whey powder, Milk Protein Concentrate (MPC), Whey Protein Concentrate (WPC), Whey Protein Isolate (WPI), etc., and is not particularly limited as long as it is generally used for food, and they may be used alone or in combination of two or more kinds. The amount of the dairy product to be added is determined in consideration of the water activity of the mixture in the constant temperature step and the flavor, texture, physical properties, quality, etc. desired for the gel-like food to be actually produced.

The eggs may be egg yolk or egg white alone or whole eggs, and may be processed into a material in the form of, for example, egg liquid or powder. The amount of eggs to be added is determined in consideration of the water activity of the mixture in the constant temperature step and the flavor, texture, physical properties, quality, etc. desired for the gel-like food to be actually produced.

The saccharide is not particularly limited, and examples thereof include granulated sugar (sucrose), honey, maple syrup, starch syrup, liquid sugar, glucose, hydrous crystalline glucose, fructose, sorbitol, xylitol, and isomaltulose, and any of them may be used alone or in combination as long as they are generally used for food production. From the viewpoint of reducing the water activity, glucose and/or starch syrup is preferably used, and starch syrup is preferably used because it can provide a suitable sweetness while reducing the water activity.

The amount of the saccharide to be added is determined in consideration of the desired sweetness of the gel-like food to be actually produced and the influence on the water activity of the mixture, and when starch syrup is used, the amount is, for example, 3 to 10% by weight, preferably 3 to 8% by weight, and more preferably 4 to 6% by weight based on the total amount of the mixture. In this case, it is preferable to use both the corn syrup and the liquid sugar, and in the case of using the liquid sugar, the amount of the liquid sugar is 9 to 18% by weight, preferably 10 to 15% by weight, and more preferably 11 to 13% by weight, based on the total amount of the mixture. On the other hand, in the same manner as in the case of the starch syrup, for example, in the case of using granulated sugar, the amount is 8 to 15% by weight, preferably 9 to 13% by weight, and more preferably 10 to 11% by weight based on the total amount of the mixture.

In addition, from the viewpoint of flavor, taste and the like in the gel food to be actually produced, the concentration of the raw water in the mixture is 20 to 35% by weight relative to the total amount of the mixture, and is preferably 23 to 33% by weight, more preferably 25 to 31% by weight in the case where the gel food is pudding or the like containing egg-derived raw material, and is preferably 20 to 30% by weight, more preferably 21 to 25% by weight in the case where the gel food is milk pudding or chocolate pudding or the like not containing egg-derived raw material. And the weight ratio of the starch syrup to the raw material water in the mixture is 0.035:1 to 0.15:1, preferably 0.04: 1 to 0.1: 1, and more preferably 0.05: 1 to 0.8: 1. On the other hand, the weight ratio of granulated sugar to raw material water in the mixture is 0.1: 1 to 0.25: 1, preferably 0.1: 1 to 0.2: 1, more preferably 0.1: 1 to 0.15: 1.

The other raw materials may contain any components that can be used in foods, and for example, flavors, seasonings, emulsifiers, tackifiers, stabilizers, colorants, and the like can be used. The present invention is also effective for use in a gel-like food containing a heat-resistant bacterium-containing material. On the other hand, puddings and milk puddings having a high ratio of eggs to dairy products in the mixture are also suitable for use in the present invention.

In the present invention, the "heat sterilization temperature" refers to a temperature sufficient for killing general bacteria other than heat-resistant bacteria, and varies depending on the sterilization method. From the viewpoint of flavor retention, bactericidal effect, and the like, continuous sterilization methods are often used, and the treatment is preferably performed at a sterilization temperature of 120 ℃ to 150 ℃, more preferably 125 ℃ to 145 ℃, and still more preferably 130 ℃ to 140 ℃. In this case, the sterilization time is preferably 1 second to 5 seconds, more preferably 1 second to 4 seconds, and still more preferably 1 second to 3 seconds. Further, a batch sterilization method may be employed, and the treatment is preferably carried out at a sterilization temperature of 90 ℃ or higher but less than 100 ℃, more preferably 93 ℃ or higher and 97 ℃ or lower, and still more preferably about 95 ℃ or higher. In this case, the sterilization time is preferably 1 minute to 10 minutes, more preferably 2 minutes to 7 minutes, and still more preferably about 5 minutes.

In the present invention, the sterilization treatment method is not particularly limited, and includes a low-temperature long-time sterilization method (LTLT method: 61.7 to 65 ℃ C., 30 minutes or more), a high-temperature short-time sterilization method (HTST method: 72 to 75 ℃ C., 15 seconds or more), an ultra-high-temperature sterilization method (UHT method: 120 to 150 ℃ C., 1 second or more and 5 seconds or less), and the like, and UHT method is preferable from the viewpoint of maintaining the flavor and the sterilization effect.

In the present invention, "undesired bacteria" refer to microorganisms undesirably mixed from raw materials, such as filamentous fungi, yeasts, and bacteria, and particularly to microorganisms present in a mixture in a constant temperature process. Among the above microorganisms, particularly problematic are bacteria that may not be killed by the sterilization treatment, for example, spore bacteria, more specifically, bacteria of the genus bacillus, and the like.

In the present invention, the "setting temperature" refers to a temperature at which the mixture is gelled (solidified) or thickened by the action of a gelling agent or a thickening agent, and the setting temperature varies depending on the type, the compounding ratio, and the like of the gelling agent or the thickening agent, and is typically about 0 to 25 ℃.

The gelling agent or thickening agent used in the present invention is not particularly limited as long as it is a gelling agent or thickening agent that dissolves in a mixture and gels or solidifies upon cooling, and examples thereof include agar, gelatin, gellan gum, xanthan gum, locust bean gum (ロ - ストビンガム), guar gum, pectin, tamarind seed pectin, locust bean gum (ロブビ - ンガム), carrageenan, and hydroxymethyl cellulose (CMC).

In this case, in the case where the gel-like food is a pudding or the like containing an egg-derived material, since a smooth texture is generally preferred, it is preferable to use carrageenan and locust bean gum together, and in the case where the gel-like food is a milk pudding or a chocolate pudding or the like containing no egg-derived material, since a texture of sand crumbling into small pieces is generally preferred, it is preferable to use agar and gelatin together.

The type and amount of gelling agent to be added are determined in consideration of the texture desired in the gel product to be actually produced and the characteristics of each gelling agent, and are, for example, 0.2 to 1 wt%, preferably 0.3 to 0.9 wt%, and more preferably 0.4 to 0.8 wt% based on the total weight of the gel food.

In the present invention, the "constant temperature step" refers to a step of holding the mixture at a certain temperature or a temperature varying within a range allowable in production. Here, the temperature is lower than the sterilization temperature and higher than the solidification temperature. The temperature in the constant temperature step depends on the sterilization temperature actually used and the solidification temperature at which gelation occurs, but is 40 to 65 ℃, preferably 45 to 60 ℃, and more preferably 50 to 55 ℃ from the viewpoint of preventing thickening (increase in viscosity) of the mixture and deterioration in flavor and the like. The time of the constant temperature step is a time required for filling the container with the entire mixture in the tank, and may be appropriately changed depending on the size of the tank, the time required for preparing the container, and the like, and is typically 1 to 6 hours. In addition, when the constant temperature step is performed for 2 hours or more, further 3 hours or more, and particularly 4 hours or more, the product quality may deteriorate significantly due to the proliferation of spore bacteria or the like.

The present invention will be described in more detail with reference to examples, which are provided by way of illustration only and are not intended to limit the scope of the present invention.

Examples

Skim milk powder (tomorrow milk Co., Ltd.), fresh cream (tomorrow milk Co., Ltd.), starch syrup (composition: glucose 8 wt%, maltose 48 wt%, maltotriose 16 wt%, and other saccharides 28 wt%) (tomorrow milk フ - ドマテリア Co., Ltd.) and raw material water were mixed in the proportions (weight ratio) described in Table 1 to prepare a mixture.

[ Table 1]

Table 1: the proportion of the mixture

	Comparative example 1	Comparative example 2	Comparative example 3	Example 1	Example 2
						Defatted milk powder	7.0	7.0	7.0	7.0	7.0
Fresh cream	6.5	6.5	6.5	6.5	6.5
						Starch syrup	13.2	18.5	22.5	26.5	39.9
Raw material water	73.3	68.0	64.0	60.0	46.6
						Total up to	100.0	100.0	100.0	100.0	100.0

The water activity obtained at this time was measured by using a water activity measuring instrument EZ-100ST (フロイント made ), and the results are shown in Table 2.

The indicator bacteria were thermophilic aerobic bacteria, and were abortive bacteria in flat pots which form spores having high heat resistance, and the mixture was inoculated with Bacillus stearothermophilus (Bacillus stearothermophilus) and then sterilized at 95 ℃ for 5 minutes. The results of counting the number of thermophilic bacteria after culturing the mixture at 60 ℃ for 8 hours are shown in Table 2.

[ Table 2]

Table 2: relationship between water activity of mixture and bacterial proliferation

	Comparative example 1	Comparative example 2	Comparative example 3	Example 1	Example 2
						Water activity	0.990	0.985	0.983	0.980	0.970
Proliferation of bacteria	+	+	+	-	-

From the above results, it was found that when the water activity of the mixture was 0.98 or less, the growth of spore-forming bacteria having high heat resistance could be suppressed in the constant temperature step for a long period of time.

It was found that when 7% of skim milk powder, 6.5% of fresh cream, and 100% of the total amount of raw material water were used, the water activity of the mixture was adjusted to 0.98 or less of the amount of each of the sugars added (the amount of each of the sugars added is necessary to suppress the proliferation of thermophilic bacteria). Further, assuming that the sweetness degree is "1" in the case of an aqueous solution (10 wt%) of granulated sugar (sucrose), relative scores are filled, and the evaluation results of the respective sweetness degrees are shown in table 3.

In addition, as a control, the water activity and sweetness of a mixture using a usual amount of granulated sugar (6.2%) were evaluated.

[ Table 3]

Table 3: relationship between sugar type and Water Activity

The amount of addition varies depending on the kind of saccharide, and glucose is the saccharide which exerts an effect at the minimum amount of addition. In addition, when the saccharide is added in an amount necessary for inhibiting the proliferation of thermophilic bacteria, the most preferable saccharide giving a sweet taste is maltose starch syrup.

Table 4 shows the ratio of pudding. As the emulsifier, for example, in the case where the gel-like food is pudding or the like containing egg-derived raw materials, since a smooth texture is generally preferred, carrageenan and locust bean gum are used together. In the case where the gel-like food is milk pudding or chocolate pudding or the like containing no egg-derived raw material, agar and gelatin are used together because the taste of sand-broken pieces is generally preferred. The other raw materials contain a fat source, a protein source, a carbohydrate source, and the like in addition to the flavor.

[ Table 4]

Table 4: proportion of pudding

Industrial applicability of the invention

According to the method of the present invention, it is possible to produce a gelatinous food product having a desired texture without impairing the flavor of the starting material while suppressing the proliferation of microorganisms that cannot be killed by ordinary sterilization treatment.

Claims (11)

1. A method for producing a gelatinous food product, comprising:

(1) a blending step of blending a mixture for producing a gel-like food;

(2) a heat sterilization step of heat sterilizing the mixture;

(3) a constant temperature step of maintaining the mixture at 40 to 65 ℃ after the heat sterilization step;

wherein the mixture contains starch syrup, and the preparation method comprises adjusting the water activity of the mixture in the constant temperature process to 0.90-0.98 by adjusting the content of the starch syrup.

2. The method of claim 1, wherein the water activity is adjusted by formulating the mixture during the compounding process.

3. The method according to claim 1 or 2, wherein the constant temperature process is preceded by a heat sterilization process in which the treatment is performed at a temperature of 95 ℃ or higher.

4. A process according to claim 1 or 2, wherein the mixture contains 3 to 10% by weight of starch syrup.

5. The method according to claim 1 or 2, wherein the weight ratio of starch syrup to raw water in the mixture is between 0.035:1 and 0.15: 1.

6. A method according to claim 1 or 2, wherein the mixture further comprises granulated sugar, and the water activity of the mixture is adjusted by adjusting the content of the starch syrup and the granulated sugar.

7. The method according to claim 1 or 2, wherein the gelatinous food product is a soft pastry.

8. Method according to claim 1 or 2, wherein the gel-like food product contains raw material from eggs and/or from milk.

9. The method according to claim 8, wherein the gelatinous food product is a pudding or a milk pudding.

10. The method according to claim 1 or 2, wherein the proliferation of the microorganism in the constant temperature step is inhibited by adjusting the water activity of the mixture.

11. The method of claim 10, wherein the microorganism is a bacillus.