JP5027099B2 - Frozen fruit processed product manufacturing method, frozen strawberry processed product, and frozen dessert using the same - Google Patents

Description

  The present invention relates to a method for producing a processed frozen fruit product, a processed frozen strawberry product, and a frozen dessert using the same.

  With the recent development of freezing technology, fruits can be stored for a long time as frozen products. Thereby, various fruits can be eaten throughout the year, and they are used in various foods.

  For example, ice cream containing frozen fruits such as candied strawberries is eaten. In this case, since the frozen fruit is candied, if it melts, it becomes hard enough to eat, but usually the texture is completely different from that of the raw fruit. Therefore, there is a demand for a processed frozen fruit product that can be eaten deliciously like raw fruit in the frozen state.

For example, Japanese Patent No. 2711593 discloses a method for processing fruit material that makes the fruit material suitable for desserts and confectionery products, for example. However, according to the method described in the above publication, only fruit materials whose texture is still different from raw fruit materials can be obtained.
Japanese Patent No. 2711593

  The present invention provides a method for producing a processed frozen fruit product having a texture like a raw fruit in a frozen state, a processed frozen strawberry product, and a frozen dessert using the same.

The method for producing a processed frozen fruit product according to one aspect of the present invention includes:
Reducing the pressure in the reaction system containing the pectinesterase-containing aqueous solution while the fruit is immersed in the pectinesterase-containing aqueous solution having a sugar content of 1 to 2 times the sugar content of the fruit;
Removing the fruit from the pectinesterase-containing aqueous solution and then immersing the fruit in a sugar-containing aqueous solution to adjust the sugar content of the fruit to 25 to 50 degrees;
Removing the fruit from the sugar-containing aqueous solution and then freezing the fruit;
including.

  The frozen strawberry processed product according to another embodiment of the present invention satisfies the following (A) to (C).

  (A) Using a device that can measure the load of a substance by linear motion, using a needle-like plunger with a root diameter of 2 mm, a compression speed of 1 mm / second, and a clearance defined by the following formula (1) as 75% The load of the processed frozen strawberry product at a product temperature of −18 ° C. is 100 to 1000 g (where the frozen strawberry product to be measured is cut in half in the major axis direction). And the measurement is performed by placing the cut surface on the measurement table in contact with the measurement table).

  (B) Using a device that can measure the load of a substance by linear motion, using a wedge plunger with an angle of 30 °, a compression speed of 10 mm / sec, and a clearance defined by the following formula (1) as 20% The load of the frozen strawberry processed product thawed at a product temperature of 10 ° C. is 900 to 2000 g (here, the frozen strawberry processed product to be measured is in a hole shape and has a major axis direction) Is measured on the measurement table so as to be horizontal with the measurement table).

  (C) The sugar content is 25 to 50 degrees.

Clearance (%) = (height of frozen strawberry processed product-moving distance of plunger) / height of frozen strawberry processed product x 100 (1)
The frozen strawberry processed product is used for the frozen dessert according to another embodiment of the present invention.

  According to the manufacturing method of the said frozen fruit processed goods, the magnitude | size of an ice crystal and the state of a fruit structure | tissue are moderately controlled in the frozen state in the frozen fruit processed goods obtained by including the said process 1-3. Therefore, according to the manufacturing method of the said frozen fruit processed goods, the frozen fruit processed goods which have a food texture like a raw fruit in a frozen state can be obtained.

  Moreover, according to the said frozen strawberry processed goods, it has food texture like a raw strawberry in a frozen state by satisfy | filling said (A)-(C).

  Hereinafter, a method for producing a processed frozen fruit product, a processed frozen strawberry product, and a frozen dessert using the same according to an embodiment of the present invention will be specifically described. In the present specification, “part” means “part by mass”, and “%” means “mass%”.

1. Process for producing frozen fruit processed product A method for producing a frozen fruit processed product according to an embodiment of the present invention comprises the step of immersing a fruit in a pectinesterase-containing aqueous solution having a sugar content of 1 to 2 times the sugar content of the fruit. A step of reducing the pressure in the reaction system containing the pectinesterase-containing aqueous solution (hereinafter referred to as “step 1”), taking out the fruit from the pectinesterase-containing aqueous solution, immersing the fruit in a sugar-containing aqueous solution, A step of adjusting the sugar content of the fruit to 25 to 50 ° C. (hereinafter referred to as “Step 2”), and a step of freezing the fruit after removing the fruit from the sugar-containing aqueous solution (hereinafter referred to as “Step 3”). And).

  When raw fruits are frozen, the water in the fruits freezes and hardens, so it is usually difficult to eat frozen fruits in a frozen state.

  On the other hand, according to the manufacturing method of the frozen fruit processed goods which concern on this embodiment, the frozen fruit processed goods obtained by performing the said process 1-process 3 are ice crystals (frozen fruit in the frozen state) The size of the fruit and the state of the fruit tissue, which are sometimes formed in the fruit and the water in the fruit is frozen and crystallized, are moderately controlled. As a result, in a frozen state, the texture is like that of a raw fruit, that is, a fresh, crisp, and moderately hard texture (specifically, when the fruit is chewed, the skin peels off and the inside A frozen fruit processed product having a texture that allows water to escape can be obtained.

1.1. Process 1
As described above, step 1 is a step of reducing the pressure in the reaction system containing the PME-containing aqueous solution while the fruit is immersed in a pectinesterase (PME) -containing aqueous solution having a sugar content of 1 to 2 times the sugar content of the fruit. is there.

1.1.1. Preparation of fruit The fruit used in the method for producing a processed frozen fruit product according to the present embodiment may be any edible fruit, for example, strawberry, apple, pear, pear, peach, pineapple, fig, banana, mango, Examples include papaya. Unlike the vegetables having mainly plant stems, leaves, and rhizomes, the fruits used in the method for producing a processed frozen fruit product according to the present embodiment are both fragile in cell membrane and cell wall. If it is not carried out by a specific method, the size of ice crystals and the state of the fruit tissue are not adequately controlled in the frozen state, and the effect of the present invention having a texture like raw fruits can be obtained even in the frozen state. Absent.
The method for producing a processed frozen fruit product according to the present embodiment is particularly useful for a fruit having a fragile cell membrane and cell wall. Examples of such a fruit include strawberries and peaches. It is preferable to prepare and use these fruits in an edible state. For example, if it's a strawberry, take a sticker, and if it's an apple or peach, peel it and cut it into an appropriate size.

1.1.2. Pectinesterase (PME) -containing aqueous solution In the method for producing a processed frozen fruit product according to this embodiment, the hardness of the fruit cell wall in the frozen state can be increased by immersing the fruit in the PME-containing aqueous solution.

  PME used in the PME-containing aqueous solution is an enzyme that catalyzes a reaction that hydrolyzes the methyl ester bond of pectinic acid to produce pectic acid and methyl alcohol. PME may be plant-derived, microorganism-derived, or prepared by genetic recombination. Further, the PME may be a purified product or a crude product. Examples of the crude product include an extract of plant tissue containing PME and a culture solution of microorganisms.

  The concentration of PME in the PME-containing aqueous solution is usually 0.0005 to 10% by mass, preferably 0.001 to 3% by mass in terms of protein contained in the enzyme with respect to 100 g of fruit. 1-1000P. E. U. , Preferably 5 to 300 p. E. U. It is. In addition, the titer of the enzyme which produces 1 mmol equivalent of acid in 1 minute is 1P. E. U. And

  In order to increase the hardness of the fruit cell wall in a frozen state by immersing the fruit in a PME-containing aqueous solution, a divalent cation such as calcium ion contained in the fruit may be sufficient, but is insufficient. In some cases, it is preferable to add a divalent cation to the PME-containing aqueous solution.

  Examples of the divalent cation include calcium chloride, calcium acetate, fermentation L-type calcium lactate, synthetic calcium lactate, calcium gluconate, monobasic calcium phosphate, calcium malate, calcium sulfate, calcium hydroxide, calcium citrate, second Examples thereof include calcium phosphate, tricalcium phosphate, bone powder, calcium carbonate, shellfish powder, and eggshell powder. Of these, calcium chloride, calcium lactate, and calcium gluconate are preferred because of their high solubility in fresh water and high calcium content.

  The concentration of the divalent cation in the PME-containing aqueous solution is usually 0.1 to 6% by weight. Preferably, it is prepared to be 0.2 to 1% by weight. When the divalent cation salt concentration is higher than 6% by weight, the fruit often becomes bitter, and when the divalent cation salt concentration is lower than 0.1% by weight, the effect cannot be expected.

  In the method for producing a processed frozen fruit product according to this embodiment, the sugar content of the PME-containing aqueous solution is adjusted to 1 to 2 times, preferably 1.0 to 2 times the sugar content of the fruit. By adjusting the sugar content of the PME-containing aqueous solution to 1 to 2 times the sugar content of the fruit, there is a balance between the penetration of the PME-containing aqueous solution into the cells constituting the fruit tissue and the elution of water from the inside of the cells to the outside. Since it is kept moderate, tissue destruction due to cell expansion can be prevented. Thereby, destruction of the structure | tissue when the immersion process to the saccharide-containing aqueous solution of the fruit mentioned later and freezing process are made, and the fall of the food texture of the frozen state accompanying it can be prevented.

  Here, when the sugar content of the PME-containing aqueous solution is less than 1 times the sugar content of the fruit, the PME-containing aqueous solution excessively penetrates into the fruit tissue and causes each cell constituting the fruit tissue to expand like a balloon. Can damage the cells, resulting in damage to the tissue. This induces the destruction of the fruit tissue and the accompanying decrease in the texture of the frozen fruit in the immersion treatment and freezing treatment of the fruit in the sugar-containing aqueous solution described later.

  That is, since fruits generally have weak tissues unlike vegetables and the like, when the sugar content of the PME-containing aqueous solution is less than 1 times the sugar content of the fruits, as described above, damage to the fruit tissues causes damage of the fruits described later. In the immersion treatment and freezing treatment in the sugar-containing aqueous solution, it induces severe destruction of the fruit tissue.

  On the other hand, when the sugar content of the PME-containing aqueous solution exceeds twice the sugar content of the fruit, excessive water flows out from each cell constituting the fruit tissue, so that the cell contracts, resulting in damage to the tissue. . This induces the destruction of the fruit tissue and the accompanying decrease in the texture of the frozen fruit in the immersion treatment and freezing treatment of the fruit in the sugar-containing aqueous solution described later.

  The sugar content of the fruit and the PME-containing aqueous solution can be measured with a commercially available sugar content meter. The sugar content of the PME-containing aqueous solution can be adjusted, for example, by blending a water-soluble substance such as a saccharide described later that can increase the sugar content.

  In the method for producing a processed frozen fruit product according to the present embodiment, the pressure when reducing the pressure in the reaction system (in the container) containing the PME-containing aqueous solution is preferably 1 to 650 mmHg, more preferably 5 to 400 mmHg, and further Preferably it is 10-100 mmHg. Although the time for depressurization depends on the size of the fruit, it is preferably 3 minutes or more, more preferably 5 minutes or more from the viewpoint that PME sufficiently penetrates and acts on the fruit. Since efficiency becomes low, it is preferably within 24 hours, more preferably within 3 hours.

  Moreover, it is preferable that the temperature of the PME containing aqueous solution in the process 1 is a temperature which PME can fully express activity, for example, is 10-50 degreeC.

1.2. Process 2
As described above, in Step 2, after removing the fruit from the PME-containing aqueous solution after Step 1, the fruit is immersed in the sugar-containing aqueous solution so that the sugar content of the fruit is 25 to 50 degrees, preferably 25 to 40 degrees. It is a process of adjusting. In step 2, by immersing in a sugar-containing aqueous solution and adjusting the sugar content of the fruit to 25 to 50 degrees, preferably 25 to 40 degrees, a fruit having an appropriate hardness close to raw fruit even in a frozen state is obtained. be able to. Moreover, after making PME act on a fruit in the process 1, a fruit structure | tissue is hard to be destroyed by immersing this fruit in sugar containing aqueous solution. Here, the frozen fruit processed product obtained by performing step 2 and step 3 without performing step 1 is too soft in the frozen state and has a poor texture compared to raw fruits.

  Here, if the sugar content of the sugar-containing aqueous solution is less than 25 degrees, ice crystals become large in the frozen state, so that a hard frozen fruit processed product may be obtained. On the other hand, if the sugar content exceeds 50 degrees, ice crystals are extremely small. Since it is formed minutely or hardly formed, the texture may become soft, or the tissue may be broken when the sugar solution penetrates into the tissue.

  In order to adjust the sugar content of the fruit to 25 to 50 degrees, preferably 25 to 40 degrees by immersing the fruit in a sugar-containing aqueous solution, the fruit contains a sugar having a sugar content of 25 to 70 degrees, preferably 25 to 60 degrees. What is necessary is just to immerse in aqueous solution. The sugar content of the sugar-containing aqueous solution can be measured with a commercially available sugar content meter.

  In order to prepare a sugar-containing aqueous solution having a sugar content of 25 to 70 degrees, for example, when the sugar is sucrose, the sugar-containing aqueous solution can be prepared by adding 33 to 233 g of sucrose to 100 g of water.

1.2.1. Sugar-containing aqueous solution The sugar-containing aqueous solution can be prepared by, for example, blending a water-soluble substance capable of increasing the sugar content such as sugar. Such a water-soluble substance is preferably a water-soluble saccharide from the viewpoint of good flavor. Examples of the water-soluble saccharide include glucose, sorbitol, sucrose, maltose, lactitol, trehalose and the like, dextrin prepared by hydrolyzing starch, and reduced dextrin as a reduced product thereof. Here, as the dextrin, commercially available products such as dextrin, starch saccharified product, starch decomposed product, starch hydrolyzed product can be used, and reduced dextrin includes reduced dextrin, dextrin alcohol, sugar alcohol, etc. What is marketed with the name of can be used.

1.2.2. Immersion treatment In the method for producing a processed frozen fruit product according to the present embodiment, the time for immersing the fruit in the sugar-containing aqueous solution depends on the size of the fruit. 30 minutes or longer, more preferably 1 hour or longer. Thus, by performing the immersion treatment for a sufficient time, the sugar content of the sugar solution and the sugar content of the fruit can be made substantially the same. In addition, since manufacturing efficiency will become low when the time of immersion treatment is too long, the time for performing immersion treatment is preferably within 24 hours, more preferably within 3 hours.

  Moreover, in the manufacturing method of the frozen fruit processed goods which concern on this embodiment, when immersing a fruit in sugar containing aqueous solution, it is preferable to set so that the product temperature of a fruit may be 1-95 degreeC, and set to 5-60 degreeC More preferably. Here, if the product temperature of the fruit is less than 1 ° C., ice crystals may be generated and penetration may not proceed, whereas if it exceeds 95 ° C., the flavor of the fruit may be impaired.

1.3. Process 3
As described above, step 3 is a step of freezing the fruit after removing the fruit from the sugar-containing aqueous solution after step 2.

  The freezing of the fruit may be performed by appropriately adjusting the conditions of the fruit after performing Steps 1 and 2 using a freezer. For example, a frozen fruit processed product can be obtained by allowing the fruit to stand for about 10 minutes to 3 hours at an air speed of 1 to 40 m / s in an atmospheric temperature of about −60 to −15 ° C.

  The obtained frozen fruit processed product is preferably stored at an atmospheric temperature of −18 ° C. or lower from the viewpoint of preventing the texture and flavor from being lowered. When stored at −18 ° C. or lower, for example, good quality can be maintained even when stored for about 2 years or less.

2. Frozen strawberry processed product The frozen strawberry processed product according to one embodiment of the present invention satisfies the following (A) to (C).

  (A) Using a device that can measure the load of a substance by linear motion, using a needle-like plunger with a root diameter of 2 mm, a compression speed of 1 mm / second, and a clearance defined by the following formula (1) as 75% The load of the processed frozen strawberry product at a product temperature of −18 ° C. is 100 to 1000 g, preferably 100 to 500 g (here, the processed frozen strawberry product to be measured is half in the major axis direction). And is measured by placing it on the measurement table in a state where the cut surface is in contact with the measurement table).

  (B) Using a device that can measure the load of a substance by linear motion, using a wedge plunger with an angle of 30 °, a compression speed of 10 mm / sec, and a clearance defined by the following formula (1) as 20% The load of the frozen strawberry processed product thawed at 10 ° C. is 900 to 2000 g, preferably 100 to 500 g (where the frozen strawberry processed product to be measured is in a hole shape) And is measured on the measurement table so that the major axis direction is horizontal to the measurement table).

  (C) The sugar content is 25 to 50 degrees.

Clearance (%) = [(height of frozen strawberry processed product−movement distance of plunger) / height of frozen strawberry processed product] × 100 (1)
In the above (A) and (B), the “major axis direction” refers to the direction from the center of the fruit (frozen strawberry processed product) to the tip of the fruit.

  In the above formula (1), “the height of the processed frozen strawberry product” means the distance from the upper surface of the measurement table of the measuring device to the maximum height of the strawberry, and “the movement distance of the plunger” It means the movement distance of the plunger in the direction perpendicular to the upper surface of the measurement table of the measuring device.

  According to the frozen strawberry processed product according to the present embodiment, by satisfying the above (A) to (C), in the frozen state, a texture like a fresh fruit (that is, fresh and moderate hardness) Have a texture).

  The frozen strawberry processed product according to this embodiment can be manufactured by the above-described method for manufacturing a frozen fruit processed product.

2.1. (A)
In the processed frozen strawberry product according to the present embodiment, the fact that “the load of the processed frozen strawberry product at −18 ° C. is 100 to 1000 g” in (A) above is eaten in a frozen state (product temperature −18 ° C.). It means that it is hard enough. That is, the load in the above (A) is a value measured on the assumption that the processed frozen strawberry product is eaten in a frozen state. Here, the temperature of −18 ° C. is because the management temperature of the frozen processed food is set to −18 ° C. or lower.

  If the load is less than 100 g, the texture is too soft and the texture is poor, while if it exceeds 1000 g, it is too hard to eat.

  In addition, the load in said (A) can be measured by the method of the Example description later mentioned.

  In addition, when a frozen strawberry processed product having a product temperature of −18 ° C. is placed in a hole shape on a measurement table for measurement, the frozen strawberry processed product is in a frozen state, so the surface is smooth and Slippery. For this reason, in (A) above, the frozen strawberry processed product cut in half in the major axis direction is the measurement object, and the frozen strawberry processed product is placed on the measurement table in a state where the cut surface is in contact with the measurement table. By measuring the load, it is possible to prevent the processed frozen strawberry product from moving on the measurement table when the plunger touches the measurement object during measurement. Thereby, stable measurement can be performed.

2.2. (B)
In the frozen strawberry processed product according to the present embodiment, the fact that “the load of the frozen strawberry processed product thawed at 10 ° C. in the product (A)” is 900 to 2000 g when melted in the mouth (product temperature 10 ° C. ) Means that the texture of the pulp is firm and crisp like a crisp raw fruit. That is, the load in (B) is a value measured assuming that the frozen strawberry processed product is eaten in a frozen state and melted in the mouth. Here, the temperature of 10 ° C. is a temperature at which almost all the frozen processed food is melted in the mouth.

  When the load is 900 to 2000 g, when a frozen frozen strawberry processed product is eaten and melted in the mouth, an appropriate texture close to that of raw strawberry is obtained.

  In addition, the load in said (B) can be measured by the method of the Example description later mentioned.

  Moreover, in the said (B), since the frozen strawberry processed goods of a measuring object are 10 degreeC of article | item temperature, compared with the frozen strawberry processed goods of article | item temperature -18 degreeC, the surface smoothness is low. For this reason, in (B) above, stable measurement can be performed on the measurement table even if the processed frozen strawberry product has a hole shape.

2.3. (C)
The sugar content of the frozen strawberry processed product according to the present embodiment is 25 to 50 degrees, preferably 25 to 40 degrees. The sugar content of raw strawberries is generally about 7 to 15 degrees, and the processed frozen strawberry product according to the present embodiment has a sugar content adjusted to a range higher than that of raw strawberries (25 to 50 degrees).

  In the present invention, the sugar content can be measured by a commercially available sugar content meter (for example, a hand-held refractometer (manufactured by Atago Co., Ltd.)).

  According to the frozen strawberry processed product according to this embodiment, by setting the sugar content to 25 to 50 degrees, preferably 25 to 40 degrees, moderate hardness is maintained in the frozen state in the frozen state, It can have a good texture close to that of strawberries.

2.4. Applications The frozen strawberry processed product according to the present embodiment can be used for various foods in a frozen state.

  The frozen strawberry processed product according to the present embodiment can be suitably used for, for example, frozen desserts. As frozen desserts, for example, ice cream (milk solid content 15% or more, milk fat content 8% or more), ice milk (milk solid content 8% or more, milk fat content 3% or more), lact ice Ice creams (milk solid content of 3% or more, milk fat content not specified), ice candy called ice confectionery, shaved ice, cracked ice, sherbet and the like can be mentioned.

  Examples of the method of using the frozen dessert include a method of using it in the frozen dessert or topping the frozen dessert.

  Alternatively, the frozen strawberry processed product according to the present embodiment may be used for a frozen cake or the like to be eaten after thawing, or may be used for various foods after thawing the frozen strawberry processed product according to the present embodiment. For example, the frozen strawberry processed product according to the present embodiment can be used as a raw material for strawberry sauce or strawberry jam as a topping application for cakes.

3. Examples Hereinafter, the present invention will be described in more detail by way of examples. However, the present invention is not limited to the examples.

3.1. Example 1 (Preparation of processed frozen strawberry products)
3.1.1. Raw fruit treatment Raw strawberry (sugar content 10 degrees) (raw material) was prepared as a fruit. The raw strawberries were washed with water, and then the cuts were removed with a knife. The sugar content was crushed by crushing raw strawberries, and the pulverized product was measured using a hand-held refractometer MASTER α (manufactured by Atago Co., Ltd.).

3.1.2. Manufacture of frozen strawberry processed product First, a PME-containing aqueous solution was prepared. That is, 12 parts of sucrose and 87 parts of fresh water and further PME were added to the stirring tank and mixed by stirring to prepare a pectinesterase (PME) -containing aqueous solution having a sugar content of 12 degrees. The amount of PME input was 50 P. per 100 g of strawberries in the immersion treatment described below. E. U. It was made to become.

  Next, 100 parts of the PME-containing aqueous solution and 100 parts of raw strawberries were put into a reduced pressure treatment tank (reaction system), the inside of the tank was decompressed to 75 mmHg, and then decompressed by holding for 10 minutes. During the decompression process, the strawberry was completely immersed in the aqueous solution containing PME. After the decompression treatment, the strawberry and the PME aqueous solution were separated by a colander, and the strawberry was taken out from the PME aqueous solution.

  Subsequently, 100 parts of a sugar-containing aqueous solution having a sugar content of 65 degrees (mixed with 65 parts of sucrose and 35 parts of fresh water) and 100 parts of the strawberry after the reduced pressure treatment are added to the double pot, and the strawberry is added to the sugar-containing aqueous solution. Soaked in. Heating was started and heated until the product temperature reached 90 ° C. After reaching the product temperature of 90 ° C., the heated sugar-containing aqueous solution and strawberry were transferred from the double kettle to a container and stored in a refrigerator at 10 ° C. to continue the immersion treatment. Ten hours after the start of soaking, the strawberry and sugar solution were separated in a colander, and the strawberry was taken out of the sugar-containing aqueous solution.

  Furthermore, using the freezer, the strawberry after the said immersion process was frozen on the conditions of -30 degreeC and the wind speed of 2-3 m / s, and the frozen strawberry processed goods were manufactured. The sugar content of the PME-containing aqueous solution and the sugar-containing aqueous solution was measured with a handheld refractometer MASTER α (manufactured by Atago Co., Ltd.).

3.2. Example 2 (Preparation of processed frozen apples)
A raw apple (raw material) cut into a 3 cm square was peeled off as a fruit to remove the core. The sugar content of this raw apple was 8 degrees. In Example 1, a processed frozen apple was produced in the same manner as in Example 1 except that this raw apple was used as a fruit and the sugar content of the PME-containing aqueous solution was adjusted to 12 degrees.

3.3. Example 3 (Preparation of frozen peach processed product)
As a fruit, a raw peach (raw material) was prepared by peeling the skin, removing the seeds, and cutting into 3 cm square. The sugar content of this raw peach was 15 degrees. A processed frozen peach product was produced in the same manner as in Example 1 except that this peach was used as a fruit in Example 1 and the sugar content of the PME-containing aqueous solution was adjusted to 18 degrees.

3.4. Example 4 (Preparation of frozen strawberry processed product)
A processed frozen strawberry product was produced in the same manner as in Example 1 except that a sugar-containing aqueous solution having a sugar content of 40 degrees was used.

3.5. Test example 1
3.5.1. Measurement of load In this test example, the load was measured under the following conditions.

(measuring equipment)
The load was measured using a texture analyzer (TA.XT plus) and a temperature control cabinet (TC / LN2). Moreover, the product temperature of the fruit was measured by installing a thermocouple at a position of about 5 mm from the surface of the pulp.

  In addition, a 2 mm diameter Stainless Steel Needle probe (manufactured by SMS) is used as a plunger for measuring the load (the load specified in (A)) of a frozen fruit processed product at a product temperature of -18 ° C. A / WEG Fracture Wedge Set Upper wedge 30mm width angle 30 ° (manufactured by SMS) was used as a plunger for measuring the load (the load specified in (B)) of the processed frozen fruit product at a temperature of 10 ° C. .

(Measurement sample preparation method)
Samples for measuring the load of frozen processed fruit products at -18 ° C are prepared by cutting the frozen fruit processed product in half with a knife in order to prevent the sample from touching the plunger during movement. It was done. The measurement sample was placed on the measurement table in a state where the cut surface produced by cutting in half was in contact with the measurement table, and the load was measured.

  In addition, the sample for measuring the load of a frozen fruit processed product having a product temperature of 10 ° C. was used while the fruit was used in a hole shape, and the load was measured by placing it on the measurement table so that the major axis direction was parallel to the measurement table.

3.5.2. Sugar content In this test example, the sugar content of the frozen fruit processed product was measured by crushing and pulverizing the frozen fruit processed product having a product temperature of 10 ° C., and measuring the pulverized product using a handheld refractometer MASTER α (manufactured by Atago Co., Ltd.).

3.5.3. Evaluation results Table 1 shows the results of the following evaluations on the processed frozen fruit products obtained in Examples 1 to 3.

  From the results of Table 1, it can be understood that the processed frozen fruit products of Examples 1 to 3 have a good texture when eaten in a frozen state (−18 ° C.).

3.6. Test example 2
The following tests were conducted in order to examine the effects of the strawberry dipping treatment in the PME-containing aqueous solution and the strawberry dipping treatment in the sugar-containing aqueous solution on the product (frozen strawberry processed product). That is, using the raw strawberry (raw material) used in Example 1, the processed strawberry product was produced by changing the treatment process as shown in Table 2 below. About the obtained processed strawberry product, the sugar content and the load were measured using the method described in Test Example 1 (in the measurement of the load, the product temperatures were −18 ° C. ± 0.2 ° C., 10 ° C. ± 0. Adjusted to a range of 2 ° C).

  Table 2 shows the results of evaluating the texture when the processed strawberry product was eaten in a frozen state (−18 ° C.).

  From the results in Table 2, it is understood that the processed frozen fruit product of Example 1 has a good texture when eaten in a frozen state (−18 ° C.) by satisfying the above (A) to (C). it can.

3.7. Test example 3
In order to investigate the effect of sugar content (processed frozen strawberry product) on strawberries, the following tests were conducted. That is, in the raw strawberry (raw material) used in Example 1 above, processed frozen strawberry products were produced by changing the sugar content of the sugar solution as shown in Table 3 below. About the obtained frozen strawberry processed goods, the sugar content and the load were measured (in the measurement of the load, the product temperature was adjusted to the range of −18 ° C. ± 0.2 ° C. and 10 ° C. ± 0.2 ° C., respectively). Moreover, the food texture when eating in the frozen state (-18 degreeC) of the obtained frozen strawberry processed product was evaluated.

  From the results of Table 3, it is understood that the frozen fruit processed product of Example 4 has a good texture when eaten in a frozen state (−18 ° C.) by satisfying the above (A) to (C). it can.

3.8. Comparative Example 5
In Example 1, a processed frozen strawberry product was produced in the same manner as in Example 1 except that sucrose was not added to the PME-containing aqueous solution (the sugar content of the used PME-containing aqueous solution was less than 1 degree). The obtained frozen strawberry processed product had a sugar content of 35 ° C., a load at −18 ° C. of 120 g, and a load at 10 ° C. of 850 g. The texture when the frozen strawberry processed product of this comparative example was eaten in a frozen state was crisp and poor in texture.

3.9. Comparative Example 6
In Example 5, a processed frozen strawberry product was produced in the same manner as in Example 5 except that the strawberry was not immersed in the PME-containing aqueous solution. The obtained frozen strawberry processed product had a sugar content of 30 ° C., the load at −18 ° C. was 300 g, and the load at 10 ° C. was 810 g. The texture when the frozen strawberry processed product of this comparative example was eaten in a frozen state was crisp and poor in texture.

3.10. Comparative Example 7
A processed frozen fruit product was prepared in the same manner as in Example 1 except that the reduced pressure treatment was not performed. As in Comparative Example 1, the obtained frozen fruit processed product had a poor texture when eaten in a frozen state.

3.11. Comparative Example 8
A processed frozen fruit product was prepared in the same manner as in Example 1 except that the PME treatment was performed using a PME-containing aqueous solution having a sugar content three times that of the fruit. The obtained processed frozen fruit product had an unpleasant texture when eaten in a frozen state, which was different from that of fresh strawberries.

3.12. Example 7 (Preparation of ice cream)
Ice cream was prepared using the processed frozen strawberry product obtained in Example 1. That is, first, 63.5 parts of milk, 15 parts of fresh cream, 15 parts of granulated sugar, 5 parts of milk powder, 1 part of an emulsion stabilizer and 0.5 part of strawberry flavor were put into a homogenizer and homogenized. Next, the product was sterilized by heating until the product temperature reached 85 ° C. and then cooled to obtain an ice cream mix. After freezing the obtained ice cream mix with an ice creamer, 100 g of this ice cream mix and one processed frozen strawberry product obtained in Example 1 were filled in a container to obtain a strawberry flavored ice cream.

  The obtained strawberry-flavored ice cream was very preferable because the frozen strawberry processed product had a crisp and good texture like a fresh strawberry.

Claims (2)

A step of depressurizing the reaction system containing the pectinesterase-containing aqueous solution at 1 to 650 mmHg for 3 minutes to 24 hours in a state where the fruit is immersed in a pectinesterase-containing aqueous solution having a sugar content of 1 to 2 times the sugar content of the fruit;
After the fruit is taken out from the pectinesterase-containing aqueous solution, the step of adjusting the sugar content of the fruit to 25 to 50 degrees by immersing the fruit in a sugar-containing aqueous solution so that the product temperature of the fruit is 1 to 95 ° C When,
Removing the fruit from the sugar-containing aqueous solution and then freezing the fruit;
A method for producing a processed frozen fruit product. The method for producing a processed frozen fruit product according to claim 1, wherein the fruit contains pectinic acid.