Method for manufacturing frozen baked bread and frozen baked bread

Abstract

To provide a method of producing post-baking frozen bread that improves quality of the post-baking frozen bread.SOLUTION: In a method of producing post-baking frozen bread comprising a cooling step of cooling post-baking bread, and a freezing step of freezing the bread after the cooling step, a water droplet adhesion step is provided, in which water droplet that is less than 15 g / m2, desirably, water droplet of 0.5-10 g / m2 is adhered almost uniformly on a surface excluding a bottom surface of the bread before the freezing step. In the water droplet adhesion step, the water droplet is adhered on the surface of the bread within three minutes immediately before freezing in the freezing step.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This invention relates to a method for producing frozen baked bread, and more particularly to a method for producing frozen baked bread in which water is applied to the surface of the bread before freezing. Furthermore, the invention relates to frozen baked bread produced by this method. [Background technology]

[0002] Generally, the distribution of pre-baked frozen bread dough has been the mainstream in the bakery industry. However, in recent years, the convenience of providing freshly baked bread has become popular, and the demand for post-baked frozen bread has also increased. This demand has spread beyond the bakery industry to mass retailers, restaurants, and other establishments. However, freezing bread makes it difficult to sufficiently suppress the deterioration of its original quality, such as color, shape, aroma, and texture. As a result, it has been difficult to enjoy the original deliciousness of thawed bread. Therefore, recently, methods for manufacturing post-baked frozen bread that suppress quality deterioration have been proposed.

[0003] Conventionally, a known method for manufacturing this type of baked and frozen bread is the technique described in Japanese Patent Publication No. 2003-219794 (Patent Document 1). This method involves impregnating the inside of baked bread with water by means of spraying, coating, or dipping the surface of the bread, and then freezing it. This makes it difficult for the crust of the bread to peel off when the frozen, water-impregnated bread is thawed or heated to return it to a edible state, thus preventing deterioration of quality such as texture. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2003-219794 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] However, in the conventional method for manufacturing frozen baked bread described above, the timing of adding water is acceptable as long as it is within the range of immediately after baking, before freezing, during freezing, or after freezing. However, for example, if water is added to bread immediately after baking, the heat of vaporization when the water evaporates causes the surface temperature of the bread to drop rapidly, making it hard and prone to peeling during freezing or frozen storage. This does not necessarily adequately prevent the peeling of the bread's surface and deterioration of its quality, such as texture.

[0006] Furthermore, if too much water is added, for reasons unknown, the moisture from the water droplets impregnating the bread surface can cause the surface tissue to turn white during freezing or frozen storage (hereinafter referred to as "whitening"), and this whitening may not disappear even after thawing. In severe cases, consumers may mistake it for "white mold," which also poses a problem in terms of inferior quality.

[0007] This invention has been made in view of these circumstances, and aims to provide a method for producing frozen baked bread and frozen baked bread that improves the quality of frozen baked bread. [Means for solving the problem]

[0008] To achieve this objective, the present invention provides a method for producing baked frozen bread, comprising a cooling step for cooling baked bread and a freezing step for freezing the bread after the cooling step, Before the freezing process described above, within 3 minutes immediately before freezing, apply approximately 15g / m² evenly to the surface of the bread, excluding the bottom surface. 2 A water droplet attachment step is provided to attach water droplets smaller than 100ml, and in the freezing step, the structure is configured to attach ice particles to the surface of the bread products.

[0009] Here, bread is made by fermenting dough, which is made primarily from cereal flour and to which water, salt, edible oils, etc. are added, and then baking it, resulting in a crust on the surface and a crumb inside. Examples of bread suitable for the present invention include French bread, hard rolls, semi-hard rolls, hot dog buns, rolls, croissants, bagels, pastries, various sweet breads, muffins, focaccia, buns, etc., with French bread, hard rolls, semi-hard rolls, hot dog buns, rolls, croissants, and bagels being particularly suitable.

[0010] In the cooling process, it is desirable to lower the temperature of the baked bread to room temperature. Cool at room temperature. If necessary, a cooling conveyor or airflow may be used.

[0011] In the water droplet deposition process, water droplet deposition can be carried out, for example, by using a general spraying device. While a nozzle that sprays water may be used, it is preferable to use a spraying device that uses a nozzle that mixes air and water and sprays it.

[0012] As a result, in the water droplet adhesion process, 15 g / m² is applied to the surface of the bread, excluding the bottom surface. 2 Tiny water droplets adhere to the bread. In this case, if water droplets are applied to baked bread immediately after baking, the moisture will evaporate easily and adhesion cannot be expected. However, since the baked bread is cooled in the cooling process, water droplets can be reliably applied. These water droplets then attempt to impregnate the crust of the bread until the freezing process. In this invention, the time from the water droplet application process to the freezing process is set to allow time for the water droplets on the surface of the bread to adhere as ice particles without being impregnated into the crust during the freezing process. Then, when the bread is frozen during the freezing process, fine ice particles, which are the remaining water droplets that have frozen, adhere almost uniformly to the surface of the bread.

[0013] And in the present invention, in the water droplet adhesion step, water droplets are adhered to the surface of the bread products within 3 minutes immediately before freezing in the freezing step. Therefore, the water droplets can surely remain on the surface of the bread products without being overly impregnated into the crust of the bread products until the freezing step, and can surely be adhered as ice particles to the bread products in the freezing step. Desirably, it is within 1 minute immediately before freezing, and more desirably, within 30 seconds immediately before freezing.

[0014] Also, if necessary, the amount of water droplets adhered to the surface of the bread products in the water droplet adhesion step is set to 0.5 to 10 g / m 2 This configuration enables the reliable exertion of the actions and effects of the present invention within this range. For example, if the amount of water droplets adhered is more than 10 g / m 2 the prevention of the whitening phenomenon becomes insufficient. On the other hand, if the amount of water droplets adhered is less than 0.5 g / m 2 the ice particles adhered to the bread surface become insufficient, and the effect of suppressing quality deterioration cannot be obtained.

[0015] Furthermore, if necessary, the average particle diameter D of the water droplets adhered to the surface of the bread products in the water droplet adhesion step is set to D = 1 mm or less. Desirably, D = 100 μm or less. With this size, the water droplets can surely be adhered. For example, if it is larger than 1 mm, the prevention of the whitening phenomenon becomes insufficient. If it is smaller than 10 μm, it is technically difficult.

[0016] Also, in order to achieve the above object, the baked and frozen bread products of the present invention have a configuration in which fine ice particles of less than 15 g / m 2 are adhered substantially uniformly to the surface excluding the bottom surface. According to such baked and frozen bread products, the same actions and effects as described above are exhibited.

[0017] In this case, it is effective that fine ice particles of 0.5 to 10 g / m 2 are adhered substantially uniformly to the surface excluding the bottom surface of the bread products. The actions and effects of the present invention can surely be exerted within this range.

Effects of the Invention

[0018] According to the present invention, compared to conventional methods of impregnating bread with water and then freezing it, this method more reliably prevents the crust from peeling off when the bread is thawed or heated to return it to a edible state, thereby preventing deterioration of quality such as texture. Furthermore, it also prevents whitening and the hardening of the bread surface due to the evaporation of water droplets adhering to the surface. Specifically, since the transition time from the water droplet application process to the freezing process is set to within 3 minutes, if water were to be applied to bread immediately after baking, the heat of vaporization as the water evaporates would cause a rapid drop in the surface temperature of the bread, making it hard and prone to peeling during freezing. In addition, during the water droplet application process, 15g / m² of water is applied to the surface of the bread, excluding the bottom surface. 2 Because tiny water droplets adhere to the bread and freeze immediately, the amount of moisture impregnated into the crust can be reduced, which suppresses the whitening phenomenon that occurs on the surface of bread after freezing, thus improving quality. [Brief explanation of the drawing]

[0019] [Figure 1] This figure shows the steps for a method of producing baked and frozen bread according to an embodiment of the present invention. [Figure 2] This is a perspective view showing a spraying device used in the water droplet application step in a method for producing baked and frozen bread according to an embodiment of the present invention. [Figure 3] This figure shows the spray patterns and flow rate distributions of various spray nozzles (a), (b), and (c). [Figure 4] This graph relates to Test Example 1 of the present invention and shows the relationship between the amount of water droplets attached to a test piece of bread and the brightness difference, "Brightness after freezing (L*) - Brightness before spraying (L*)", which is an indicator of the degree of whitening. [Figure 5] This is a table-like diagram relating to Test Example 2 of the present invention, showing the relationship between the time from when water droplets are applied to bread products until they are frozen, and the resulting whitening. [Figure 6]This is a diagram illustrating the composition (a) and manufacturing process (b) of a semi-hard roll bread used as a test specimen, relating to Test Example 3 of the present invention. [Figure 7] This figure shows a method for measuring crust peeling of a semi-hard roll bread as a test specimen, relating to Test Example 3 of the present invention. [Figure 8] This figure relates to Test Example 3 of the present invention and shows the relationship between the amount of water droplets attached to a test piece of bread and the degree of peeling. [Figure 9] This table shows Examples 1 to 3 of the present invention together with Comparative Examples 1 to 13. [Modes for carrying out the invention]

[0020] The method for producing baked and frozen bread products and the baked and frozen bread products according to embodiments of the present invention will be described in detail below with reference to the attached drawings. The method for producing baked and frozen bread according to an embodiment of the present invention, as shown in Figure 1, comprises a cooling step (1) for cooling the baked bread, a water droplet application step (2) for applying water droplets to the surface of the bread excluding the bottom surface after the cooling step, and a freezing step (3) for freezing the bread after the water droplet application step. Each step will be described below.

[0021] Here, bread is made by fermenting dough, which is made primarily from cereal flour and to which water, salt, edible oils, etc. are added, and then baking it, resulting in a crust on the surface and a crumb inside. Examples of bread suitable for the present invention include French bread, hard rolls, semi-hard rolls, hot dog buns, rolls, croissants, bagels, pastries, various sweet breads, muffins, focaccia, buns, etc., with French bread, hard rolls, semi-hard rolls, hot dog buns, rolls, croissants, and bagels being particularly suitable.

[0022] (1) Cooling process The baked bread is cooled. In this cooling process, the temperature of the baked bread is lowered to room temperature. Cooling to room temperature is possible, and if necessary, a cooling conveyor or airflow may be used.

[0023] (2) Water droplet adhesion process Water droplets less than 15 g / m are adhered uniformly to the surface of the bread excluding the bottom surface. Preferably, it is 0.5 - 10 g / m 2 less. In this water droplet adhesion process, the adhesion of water droplets is carried out using, for example, a spraying device as shown in Fig. 2. This spraying device includes a water-permeable mesh belt conveyor for transporting baked bread, and a nozzle provided above the belt conveyor via a stand for injecting a mist of air and water onto the bread on the belt conveyor. The injection nozzle is directed downward and installed at a position perpendicular to the belt conveyor. A nozzle with a fan-shaped spray pattern with an injection angle of 110 degrees is used, and it is set to spread in the short side direction of the belt conveyor, and a mist with an average particle diameter of 20 μm - 100 μm is injected from the injection nozzle. The amount of water droplets is adjusted by the conveying speed of the belt conveyor and the injection amount from the injection nozzle, and water droplets can be evenly adhered to the surface of the bread at any position on the belt conveyor. As shown in Fig. 3, the injection nozzle has a fan-shaped spray pattern (a), a hollow conical spray pattern (b), and a full conical spray pattern (c). When spraying using an injection nozzle other than the fan-shaped spray pattern, depending on the position of the belt conveyor, the amount of water adhering to the water droplets is different and unevenness occurs, so it is not suitable for the implementation of the present invention.

[0024] Also, in the water droplet adhesion process, if the time from when the water droplets are injected and adhered to the bread until reaching the freezing process is too long, the bread will be impregnated with the crumb of the bread. Therefore, the time from the water droplet adhesion process to the freezing process is set within 3 minutes. In the embodiment, water droplets are adhered to the surface of the bread within 3 minutes immediately before freezing in the freezing process. Preferably, it is within 1 minute immediately before freezing, and more preferably, within 30 seconds immediately before freezing.

[0025] Furthermore, in the water droplet adhesion process, water droplets less than 15 g / m 2 are adhered to the surface of the bread excluding the bottom surface. Preferably, it is 0.5 - 10 g / m 2 ​​Water droplets are attached to the surface of the bread. Furthermore, the average particle size D of the water droplets attached to the surface of the bread is kept to D=1mm or less. Preferably, D=100μm or less.

[0026] (3) Freezing process The bread is frozen using a freezer or a dedicated freezer. The freezing temperature is, for example, -50°C to -30°C. In this freezing process, when the bread is frozen, water droplets attached to the surface of the bread freeze and form ice crystals, and these fine ice crystals, formed from frozen water droplets, adhere almost uniformly to the surface of the bread. As a result, 15g / m² of ice crystals adhere almost uniformly to the surface of the bread, except for the bottom. 2 Water droplets smaller than 0.5-10 g / m², preferably 0.5-10 g / m². 2 This process produces baked and frozen bread products in which fine ice particles, formed by the freezing of water droplets, are attached almost uniformly.

[0027] Therefore, compared to conventional methods of impregnating bread with water and then freezing it, this manufacturing method more reliably prevents the crust from peeling off when the frozen bread is thawed or heated to return it to a edible state, thus preventing deterioration of quality such as texture. Furthermore, it also prevents whitening and the hardening of the bread surface due to the evaporation of water droplets attached to the surface. Specifically, since the transition time from the water droplet application process to the freezing process is set to within 3 minutes, if water is applied to bread immediately after baking, the heat of vaporization as the water evaporates causes a rapid drop in the surface temperature of the bread, which hardens it and makes it more prone to peeling during freezing. 2 Because tiny water droplets adhere to the bread and freeze immediately, the amount of moisture impregnated into the crust is reduced, which suppresses the whitening phenomenon that occurs on the surface of bread after freezing, thus improving quality.

[0028] Next, we will show an example of a test. <Test Example 1> The relationship between the amount of water droplets applied to bread and whitening was investigated. 2g of bread dough was flattened into a cracker-like shape and baked to create numerous crust models (test pieces) with a diameter of 60mm and a thickness of 1mm. Three of these crust models were then treated with 0g / m³ of water. 2 10g / m 2 12.5g / m 2 15g / m 2 25g / m 2 37.5g / m 2 Water droplets were sprayed, and after 30 seconds, the crust model was rapidly frozen in a shock freezer. After that, the crust model was removed from the shock freezer and its lightness (L*) was measured. The surface lightness (L*) was also measured before spraying. The relationship between the spray volume and the crust color difference "lightness after freezing (L*) - lightness before spraying (L*)" was then obtained. The amount of water sprayed was adjusted using the apparatus shown in Figure 2, by spraying a constant amount of water from the nozzle and adjusting the conveyor speed. The conveyor speed and the unit area (m²) were determined in advance. 2 The relationship between the amount of spray per unit area was determined, and the amount of spray applied to the crust model (test specimen) was calculated.

[0029] The results are shown in Figure 4. Figure 4(a) is a graph showing the relationship between the spray amount and the crust color difference "lightness after freezing (L*) - lightness before spraying (L*)" (degree of whitening), and Figure 4(b) shows the underlying numerical data and the visual evaluation of whitening. 15g / m 2 It was found that whitening could be suppressed with a spray volume below a certain level, and that whitening was more likely to occur with a larger spray volume.

[0030] <Test Example 2> We investigated the relationship between the time it takes for water droplets to adhere to bread products and freeze, the state of the ice crystals after freezing, and the whitening observed after thawing. A crust model (test specimen) was prepared as follows: The top crust portion of a square loaf of bread was cut to a thickness of 5 mm to obtain a flat crust.

[0031] As shown in Figure 5, water (0.03g / drop) was dropped one drop at a time at five locations on the crust. The diameter of the water droplets and the degree of penetration were checked at 0 seconds, 30 seconds, 1 minute, 3 minutes, and 5 minutes after dropping. The water droplets spread out over time after dropping. Penetration into the bread was observed from around 1 minute onwards.

[0032] When water is dropped onto bread and then rapidly frozen at -38°C for 15 minutes in a freezer, the dropped water freezes into ice crystals that adhere to the bread. After more than 3 minutes, the diameter of the ice crystals doubles. Also, after more than 3 minutes, if the water droplets are small, it is highly likely that the droplets will soak into the bread and the crystals will disappear. If the water droplets are large, it is highly likely that the ice crystals will fuse together and lose their granular properties.

[0033] After being frozen at -20°C for 7 days, the test specimens were thawed at room temperature for 30 minutes, and the whitening state was observed. When frozen within 30 seconds of water application, no whitening was observed. On the other hand, a very slight whitening was observed in the parts that were frozen 1 minute after water application, and clear whitening was observed in the frozen parts after 5 minutes. From these results, it was found that it is preferable to apply water droplets to the surface of the bread within 3 minutes immediately before freezing.

[0034] <Test Example 3> We conducted tests to investigate the relationship between the amount of water droplets applied to bread products and their subsequent detachment. Eighteen semi-hard rolls prepared according to the method shown in Figure 6 were used as test specimens. These were divided into three sections, with six pieces each, and 0 g / m² was applied to each section. 2 10g / m 2 20g / m 2 Water droplets were applied to the semi-hard rolls, and after 30 seconds, they were rapidly frozen in a shock freezer. After that, the semi-hard rolls were removed from the shock freezer, and the peeling condition was observed after thawing. As shown in Figure 7, the semi-hard roll test pieces were cut into 1 cm thick slices, and the presence or absence of gaps between the crumb and crust was examined in each slice (total number of slices: 62). The peeling risk, as defined below, was then measured and evaluated based on the degree of peeling of the semi-hard rolls. Bark peeling risk (%) = (Number of pieces with gaps) ÷ (Total number of pieces) × 100

[0035] The results are shown in Figure 8. Figure 8(a) is a graph showing the relationship between the amount of water sprayed on semi-hard rolls and the risk of crust peeling, and Figure 8(b) shows the underlying numerical data and visual evaluation of whitening and texture. 10, 20 g / m 2 Both are 0g / m 2 Compared to that, the risk of peeling was reduced by approximately half. Also, 20g / m 2 is 10g / m 2 There was no advantage in peeling compared to 20g / m 2 There was a bleaching phenomenon. [Examples]

[0036] Figure 9 shows Examples 1-3 along with Comparative Examples 1-13. Examples 1-3 were manufactured based on the above test examples. In all cases, compared to the comparative examples, peeling was reduced, whitening was reduced, and the appearance quality was superior, as was the texture.

[0037] In the above examples, semi-hard rolls, small French bread, and dinner rolls were tested, but the test is not limited to these, and can be modified as appropriate. The present invention is not limited to the embodiments described above, and those skilled in the art will readily be able to make many modifications to these exemplary embodiments without substantially departing from the novel teachings and effects of the present invention, and many of these modifications will fall within the scope of the present invention.

Claims

1. A method for manufacturing frozen baked bread, comprising a cooling step for cooling baked bread and a freezing step for freezing the baked bread after the cooling step, Before the freezing process described above, within 3 minutes immediately before freezing, apply approximately uniformly 0.5 g / m² to 15 g / m² to the surface of the bread products, excluding the bottom surface. ２ A method for producing baked frozen bread, characterized by including a water droplet attachment step in which water droplets less than a certain amount are attached, and attaching ice particles to the surface of the bread in the freezing step.

2. The method for producing baked and frozen bread according to claim 1, characterized in that the water droplet attachment step involves attaching water droplets to the surface of the bread within one minute immediately before freezing in the freezing step.

3. The amount of water droplets to be applied to the surface of the bread products in the above water droplet application process is 0.5 to 10 g / m². ２ A method for producing baked and frozen bread according to claim 1 or 2, characterized by the following:

4. In frozen baked bread products in which water droplets are applied to the surface of baked bread products and then frozen, On the surface of the above bread products, excluding the bottom, apply 0.5 g / m² to 15 g / m². ２ A post-baked and frozen bread product characterized by having fine ice particles of less than 100mm attached almost uniformly.

5. On the surface of the above bread products, excluding the bottom, apply 0.5 to 10 g / m². ２ The baked and frozen bread products according to claim 4, characterized in that fine ice particles are attached almost uniformly.

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