Dried vegetables and method for producing dried vegetables

Abstract

To provide dried vegetables in which sugar precipitation is suppressed, and a method for producing dried vegetables capable of suppressing sugar precipitation. [Solution] The present invention relates to a method for producing dried vegetables, comprising the steps of mixing blanched vegetables with carbohydrates to obtain vegetables containing carbohydrates, and drying the vegetables containing carbohydrates, wherein the carbohydrates are trehalose and / or cyclodextrin. The present invention also relates to dried vegetables obtained by the method for producing dried vegetables.

Description

[Technical field]

[0001] The present invention relates to dried vegetables and a method for producing dried vegetables. [Background technology]

[0002] Dried vegetables are widely used as ingredients for instant foods such as instant noodles, instant soups, and instant miso soup, snack foods, etc. In general, dried vegetables are produced by slicing or cutting vegetables into small pieces and then subjecting them to a drying process such as hot air drying or freeze drying. However, dried vegetables produced by hot air drying have the disadvantages of poor rehydration properties and discoloration, fading, browning, etc. Furthermore, when these vegetables are rehydrated in hot water, they suffer from discoloration and deterioration that is significantly different from the original color tone of the vegetables, and have poor flavor.

[0003] In recent years, dried vegetables for instant foods that can prevent discoloration or fading during storage have been proposed. For example, Patent Document 1 describes dried green vegetables for instant foods that are dried with hot air, and are characterized in that they contain 10% by weight or more of maltose and / or lactose, have a water content of 14% by weight or less, have a total sugar content of 65 to 80% by weight, and have a pH of 7 to 8 when diluted 20 times in water. When dried vegetables contain a large amount of sugar, the sugar precipitates from the vegetables, making them sticky and reducing manufacturability (manufacturing efficiency, ease of manufacturing, etc.). Regarding this point, Patent Document 1 describes that the stickiness caused by sugar can be suppressed by adding lactose. However, in production lines where long hours of work are carried out in high-temperature, high-humidity environments, it is difficult to prevent stickiness of dried vegetables due to sugar precipitation by adding lactose alone. In particular, in humid seasons, dried vegetables that had good fluidity for the automatic parts supplying device in the production line can become sticky and the vegetables can clump together, causing problems in the production line. In addition, when sugar precipitates on the surface of vegetables, there is also the problem that the vegetables look like they are growing mold. For these reasons, there is a demand for dried vegetables that can suppress sugar precipitation during storage.

[0004] Patent Document 2 also describes that by soaking the vegetables for 2 to 30 minutes in an aqueous carbohydrate solution containing 7.5 to 25% by mass of a carbohydrate derivative of α,α-trehalose at a temperature of 40°C or higher (lower than the blanching treatment temperature), carbohydrate-containing dried vegetables can be obtained that have excellent reconstitution properties and exhibit good shape, color, and flavor after reconstitution. However, because carbohydrates remain on the surface of dried vegetables, there is a risk that production lines will be disrupted if the production is continued for an extended period of time.

[0005] Patent Document 3 discloses a method for inhibiting sugar precipitation. The method for inhibiting sugar precipitation described in Patent Document 3 is characterized in that a polysaccharide is contained in a solution containing a high concentration of sugar. This method can effectively inhibit sugar precipitation or crystallization that occurs during storage of a solution containing a high concentration of sugar, but its effectiveness in the case of dried vegetables has not been verified. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6694786 [Patent Document 2] Patent No. 5172694 [Patent Document 3] Patent No. 4643280 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide dried vegetables in which sugar precipitation is suppressed, and a method for producing dried vegetables in which sugar precipitation can be suppressed. [Means for solving the problem]

[0008] The present inventors have found that mixing trehalose and / or cyclodextrin with blanched vegetables and then drying the vegetables can suppress sugar precipitation during storage. The present invention was completed based on this finding.

[0009] That is, the present invention is as follows. Section 1. A step of mixing the blanched vegetables with carbohydrates to obtain carbohydrate-containing vegetables; and The method includes a step of drying vegetables containing carbohydrates. A method for producing dried vegetables, comprising: A method for producing dried vegetables, wherein the carbohydrate is trehalose and / or cyclodextrin. Section 2. Item 1. The method for producing dried vegetables according to Item 1, wherein the blanched vegetables have a product temperature of less than 40 ° C. Section 3. Item 2. The method for producing dried vegetables according to Item 1, wherein the pH of a 20-fold diluted aqueous solution of the dried vegetables is less than 7.0. Section 4. Item 2. The method for producing dried vegetables according to Item 1, wherein the amount of the carbohydrate added is 1 part by mass to 25 parts by mass with respect to 100 parts by mass of the blanched vegetables. Section 5. Item 2. The method for producing dried vegetables according to Item 1, wherein the carbohydrate is a mixture containing trehalose and cyclodextrin. Section 6. Item 2. The method for producing dried vegetables according to Item 1, wherein the carbohydrate is trehalose. Section 7. Immediately after the production of the dried vegetables, CIE1976-L * a * b *L in color space * Value, CIE1976-L of dried vegetables after 14 days of storage at 35℃ and 75% humidity * a * b * L in color space * Difference from the value (ΔL * The method for producing dried vegetables according to claim 1, wherein the value of the dried vegetable extract is 2.0 or less. Section 8. Item 1. The method for producing dried vegetables according to Item 1, wherein the dried vegetables are dried vegetables in which sugar precipitation is suppressed. Section 9. Item 9. A dried vegetable obtained by the method for producing dried vegetables according to any one of items 1 to 8. Section 10. An agent for inhibiting sugar precipitation in dried vegetables, comprising trehalose and / or cyclodextrin. Section 11. A method for inhibiting sugar precipitation in dried vegetables, comprising a step of adding trehalose and / or cyclodextrin to vegetables. Section 12. A process for blanching vegetables; cooling the blanched vegetables; Mixing the cooled vegetables with carbohydrates to obtain carbohydrate-containing vegetables; and The method includes a step of drying vegetables containing carbohydrates. A method for inhibiting sugar precipitation in dried vegetables, comprising: A method for inhibiting sugar precipitation in dried vegetables, wherein the carbohydrate is trehalose and / or cyclodextrin.

[0010] In addition, since it is currently impossible or so difficult as to be impractical to completely specify the structure of the above-mentioned "dried vegetables obtained by the manufacturing method for dried vegetables," the invention of the product is described using a product-by-process claim. Effect of the Invention

[0011] According to the present invention, it is possible to provide dried vegetables in which sugar precipitation is suppressed, and a method for producing dried vegetables in which sugar precipitation can be suppressed. In addition, according to the present invention, since sugar precipitation in dried vegetables can be suppressed, excessive sweetness and stickiness can be suppressed, and dried vegetables can be obtained that can be stored for long periods of time even in containers for instant foods that have poor storage properties. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a photograph of the dried vegetables of Example 16 before the accelerated test. [Diagram 2] FIG. 2 is a photograph of the dried vegetables of Example 16 after the accelerated test. [Diagram 3] FIG. 3 is a photograph of the dried vegetables of Comparative Example 13 before the accelerated test. [Figure 4] FIG. 4 is a photograph of the dried vegetables of Comparative Example 13 after the accelerated test. [Diagram 5] FIG. 5 is a photograph of the dried vegetables of Example 1 before the accelerated test. [Figure 6] FIG. 6 is a photograph of the dried vegetables of Example 1 after the accelerated test. [Figure 7] FIG. 7 is a photograph of the dried vegetables of Comparative Example 1 before the accelerated test. [Figure 8] FIG. 8 is a photograph of the dried vegetables of Comparative Example 1 after the accelerated test. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The method for producing dried vegetables of the present invention will be described in detail below. However, the present invention is not limited to the following description.

[0014] Method for producing dried vegetables The method for producing dried vegetables of the present invention is as follows: A step of mixing the blanched vegetables with carbohydrates to obtain carbohydrate-containing vegetables; and The method includes a step of drying vegetables containing carbohydrates. A method for producing dried vegetables, comprising: The carbohydrate is trehalose and / or cyclodextrin. Here, the term "vegetables containing carbohydrates" refers not only to those that are attached to the surface of the vegetable, but also to those that have carbohydrates that have penetrated into the interior of the vegetable and been absorbed.

[0015] 1st process The first step is to mix blanched vegetables with carbohydrates to obtain carbohydrate-containing vegetables. The vegetables used in the present invention are not limited to a specific type. Examples of vegetables include leafy vegetables and root vegetables. Specific examples of the leafy vegetables include vegetables from the Brassicaceae, Amaranthaceae, Asteraceae, Amaryllidaceae, Tilia, and Apiaceae families. Examples of the Brassicaceae family include cabbage, bok choy, komatsuna, Nozawana, Chinese cabbage, and kale. Examples of the Amaranthaceae family include spinach. Examples of the Asteraceae family include lettuce, chicory, and garland chrysanthemum. Examples of the Amaryllidaceae family include green onions and Chinese chives. Examples of the Tilia family include molokheiya. Examples of the Apiaceae family include angelica tree and the like. The vegetables also include leafy vegetables other than those mentioned above, such as bean sprouts, taros, young tea leaves, tree buds, and perilla leaves.

[0016] The method for producing dried vegetables of the present invention may include a step of washing the vegetables and cutting them to a desired size prior to the first step. If necessary, the vegetables may be washed and then sterilized with hypochlorous acid, etc. After washing, the vegetables may be directly blanched, or, if necessary, the edible parts may be removed and cut into small pieces of an appropriate size. Cutting includes slicing, cutting, crushing, etc. The size of the cut is not particularly limited. For example, in the case of the leafy vegetables, it is suitable to cut them to a length of usually about 3 to 50 mm, preferably about 5 to 40 mm. In the case of the root vegetables, it is suitable to cut them to a thickness of usually about 1 to 15 mm, preferably about 3 to 10 mm.

[0017] In this specification, "blanching" refers to heat treatment with an aqueous heat medium (e.g., hot water, heated steam, etc.) performed as a pretreatment when processing raw vegetables, and is usually performed by immersing raw vegetables in hot water for a relatively short period of time. This inactivates enzymes contained in the vegetables, thereby improving the shelf life of the vegetables. Heat treatment is not limited to the aqueous heat medium, and other heating means, such as Joule heating, infrared heating, microwave heating, and high-frequency heating, can also be used for heat treatment. Blanching conditions vary depending on the type of vegetable, heating means, etc. For example, the heating temperature is usually above 90° C., and preferably 95° C. or higher. The heating time is usually about 10 seconds to 20 minutes, and preferably about 30 seconds to 10 minutes.

[0018] The blanched vegetables are cooled and drained, if necessary, and then mixed with the carbohydrate. The blanched vegetables are preferably cooled until the product temperature is less than 40° C. The cooling means is not particularly limited, and any means such as water cooling, ice cooling, and air cooling may be used, with water cooling being preferred. For water cooling, a cooling liquid between 0° C. and room temperature can be used. The cooling liquid can be water, running water, or the like.

[0019] The carbohydrate includes monosaccharides, polysaccharides, sugar alcohols, etc. The carbohydrate used in the present invention is trehalose and / or cyclodextrin. The carbohydrate may be trehalose alone or cyclodextrin alone, or may be a mixture containing trehalose and cyclodextrin.

[0020] Trehalose is a disaccharide formed by 1,1-glycosidic bonds between glucose units.

[0021] Cyclodextrins (hereafter sometimes referred to as "CD") are cyclic oligosaccharides formed from glucose molecules linked through α-1,4-glucosidic bonds. Cyclodextrins contain a Greek letter as a prefix depending on the number of glucose molecules that make up the cyclodextrin. Such cyclodextrin is not particularly limited, and examples thereof include α-cyclodextrin having 6 glucose molecules, β-cyclodextrin having 7 glucose molecules, γ-dextrin having 8 glucose molecules, and δ-cyclodextrin having 9 glucose molecules. These cyclodextrins can be used alone or in combination of two or more. As the cyclodextrin (CD), α-cyclodextrin is preferred.

[0022] The amount of carbohydrate added is preferably 1 to 25 parts by mass, more preferably 1 to 20 parts by mass, and even more preferably 1 to 10 parts by mass, relative to 100 parts by mass of the blanched vegetables. The mass of the blanched vegetables is the mass including the water content of the vegetables after draining. Here, "draining" refers to removing water adhering to the surface of vegetables. Draining may be performed using, for example, a basket-type cone separator, an automatic food dehydrator, or the like. It may also be performed by spreading the blanched vegetables on a colander or the like and leaving them to stand. The amount of carbohydrate added refers to the amount of trehalose only when no cyclodextrin is contained, refers to the amount of cyclodextrin only when no trehalose is contained, and refers to the total amount of trehalose and cyclodextrin when both trehalose and cyclodextrin are contained.

[0023] The carbohydrate to be mixed with the blanched vegetables may further contain carbohydrates other than trehalose and / or cyclodextrin as cheaper carbohydrates from a cost standpoint. Examples of carbohydrates other than trehalose and / or cyclodextrin (hereinafter also referred to as other carbohydrates) include monosaccharides such as glucose and fructose, and disaccharides such as lactose, maltose, and sucrose. Among these, preferred other carbohydrates include monosaccharides such as glucose, and disaccharides such as lactose and maltose. When other carbohydrates are added, the amount added is preferably 24 parts by mass or less, more preferably 0.01 to 19 parts by mass, and even more preferably 0.1 to 9 parts by mass, relative to 100 parts by mass of the blanched vegetables. Furthermore, when other carbohydrates are added together with trehalose and / or cyclodextrin, it is preferable that the total amount of all carbohydrates added is 25 parts by mass or less per 100 parts by mass of the blanched vegetables.

[0024] The carbohydrate may be mixed with the vegetables in a powdered state, or may be mixed with the vegetables as an aqueous solution of the carbohydrate. Alternatively, the carbohydrate may be mixed with the vegetables by immersing the vegetables in the aqueous solution of the carbohydrate. From the viewpoint of ease of operation, it is preferable to mix the carbohydrate with the vegetables as it is in a powdered state. The means for mixing the vegetables and the carbohydrate is not particularly limited as long as the carbohydrate is evenly applied to the surface of the vegetables, and can be carried out using, for example, a spiral mixer, a rheokneader, etc.

[0025] 2nd process The second step is a step of drying the carbohydrate-containing vegetables obtained in the first step. There are no particular limitations on the drying means as long as it can sufficiently reduce the amount of moisture contained in the carbohydrate-containing vegetables. Examples of drying means include hot air, freezing, vacuum freezing, dry heat, microwaves, infrared rays, and the like. Hot air drying is preferred because it allows drying in a relatively short time and does not affect the texture of the vegetables. Specifically, a hot air dryer or the like can be used. The temperature of the hot air in hot air drying is usually 120°C or less, and preferably 100°C or less. More specifically, it is preferably 40 to 120°C, more preferably 45 to 110°C, and even more preferably 50 to 90°C. The drying temperature here may be gradually increased within the above temperature range, or may be increased in two or more stages. The drying time varies depending on the drying means and drying temperature, but is usually about 1 to 24 hours, preferably about 2 to 12 hours.

[0026] Dried vegetables The above-mentioned method for producing dried vegetables can provide dried vegetables in which sugar precipitation is suppressed. The obtained dried vegetables can suppress sugar precipitation during storage. In addition, since sugar precipitation is suppressed in the dried vegetables of the present invention, excessive sweetness and stickiness are suppressed, and the dried vegetables can be stored for a long time even in containers for instant foods that have poor storage properties.

[0027] The moisture content in the dried vegetables is preferably low, specifically, preferably 14% by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less. The moisture content may be measured by a normal pressure drying method under drying conditions of 105°C and 4 hours. The carbohydrate content in the dried vegetables is usually 5 to 85% by mass, preferably 45 to 83% by mass, and more preferably 50 to 80% by mass. The carbohydrate content can be measured, for example, by HPLC (high performance liquid chromatography).

[0028] Furthermore, the pH of the dried vegetables is preferably less than 7.0, more preferably 5.8 to 6.9, and even more preferably 6.2 to 6.9, in a 20-fold diluted aqueous solution of the dried vegetables. For example, the pH can be measured by adding 190 g of pure water to 10 g of dried vegetables, pulverizing and stirring in a mixer, and measuring the pH of the 20-fold diluted aqueous solution containing the pulverized vegetables with a pH meter (electrode type) while stirring.

[0029] Immediately after the production of the dried vegetables, CIE1976-L * a * b * L in color space * value and CIE1976-L after storage for 14 days at 35°C and 75% humidity * a * b * L of dried vegetables in color system * Difference from the value (ΔL * value) is preferably 2.0 or less, more preferably 1.7 or less, even more preferably 1.5 or less, particularly preferably 1.0 or less, and most preferably 0.85 or less.

[0030] Immediately after the production of the dried vegetables, CIE1976-L * a * b * A in color space * value and CIE1976-L after storage for 14 days at 35°C and 75% humidity * a * b * Color space for dried vegetables * Difference from the value (Δa * The value of Δa is preferably 5.0 or less, and more preferably 4.0 or less. * The value is when the vegetables are green leafy vegetables, and Δa * The value may vary.

[0031] Immediately after the production of the dried vegetables, CIE1976-L * a * b * b in color space *value and CIE1976-L after storage for 14 days at 35°C and 75% humidity * a * b * Color system for dried vegetables b * Difference from the value (Δb * The value of Δb is preferably 3.0 or less, and more preferably 2.5 or less. * The value is when the vegetables are green leafy vegetables, and Δb * The value may vary.

[0032] CIE1976-L * a * b * L in color space * Value, a * value and b * The value can be measured using a color difference meter.

[0033] The dried vegetables obtained by the above-mentioned method for producing dried vegetables can be rehydrated (reconstituted) by cooking with hot water, cooking in a pot, cooking in a microwave oven, or the like, and used as ingredients for instant foods.

[0034] Agent for inhibiting sugar precipitation in dried vegetables and method for inhibiting sugar precipitation in dried vegetables The present invention includes an agent for inhibiting sugar precipitation in dried vegetables, which contains trehalose and / or cyclodextrin. The present invention also includes a method for inhibiting sugar precipitation from dried vegetables, comprising the step of adding trehalose and / or cyclodextrin to vegetables. The method for inhibiting sugar precipitation in dried vegetables comprises: A process for blanching vegetables; cooling the blanched vegetables; Mixing the cooled vegetables with carbohydrates to obtain carbohydrate-containing vegetables; and The method includes a step of drying vegetables containing carbohydrates. A method for inhibiting sugar precipitation in dried vegetables, comprising: This is a method for inhibiting sugar precipitation in dried vegetables, wherein the carbohydrate is trehalose and / or cyclodextrin. EXAMPLES

[0035] Hereinafter, the present invention will be described more specifically by way of examples, but the technical scope of the present invention is not limited to these exemplifications.

[0036] The sugars used in the following examples and comparative examples are as follows. · Glucose: anhydrous crystalline glucose manufactured by San-Ei Chemical Co., Ltd. · Lactose: lactose manufactured by Reprino Foods · Maltose: Shiro, a product of Hayashibara Co., Ltd. (registered trademark) · Trehalose: Treha (registered trademark) manufactured by Hayashibara Co., Ltd.

[0037] <Experimental Example 1> The influence of the type of sugar on the sugar precipitation of dried vegetables was examined. Example 1 After washing the leaves of fresh cabbage with water, they were cut into 30 mm × 30 mm pieces, and 120 g of cabbage was boiled in boiling water (1 L) at 98°C for 2 minutes. This cabbage was taken out in a colander once, placed in a running water tank, and cooled so that the product temperature of the cabbage was less than 40°C. Then, in order to remove excess moisture, it was drained in a colander, and about 120 g of the drained cabbage was obtained. To 100 parts by mass of the obtained drained cabbage, 20 parts by mass of trehalose was mixed and allowed to stand at 25°C for 1 hour. Then, it was dried with hot air at 80°C for 2.5 hours using a dryer (manufactured by Philips, product name: Non-Fryer) to obtain about 20 g of the dried vegetable (cabbage) of Example 1. The water content of the dried vegetable of Example 1 was 10%, and the water activity was about 0.3 or less. In the present disclosure, the water content used was the value measured by the normal pressure heating drying method, and the water activity used was the value measured by a water activity measuring device (manufactured by Meter Japan Co., Ltd., product name: Water Activity Measuring Device AquaLab).

[0038] <pH measurement> The pH was measured for the 20-fold diluted aqueous solution of the dried vegetables obtained in Example 1. Specifically, 190 g of pure water was added to 10 g of dried vegetables, and the mixture was pulverized and stirred in a mixer, and the pH of the 20-fold diluted solution containing the pulverized cabbage was measured with a pH meter (electrode type) (manufactured by Horiba, Ltd., product name: tabletop pH meter F-72) while stirring. The pH of the dried vegetables of Example 1 (20-fold diluted aqueous solution) was 6.4.

[0039] Examples 2 to 12 and Comparative Examples 1 to 7 The dried vegetables of Examples 2 to 12 and Comparative Examples 1 to 7 were obtained by the same production method as in Example 1, except that the carbohydrates shown in Tables 1 to 3 below were used in the amounts (parts by mass) shown in Tables 1 to 3 below. The pH of the dried vegetables in Examples 2 to 12 (20-fold diluted aqueous solution) was less than 7.0 (6.1 to 6.8).

[0040] <Test Example> The dried vegetables obtained in Examples 1 to 12 and Comparative Examples 1 to 7 were subjected to an acceleration test as follows.

[0041] Acceleration Test The dried vegetables were placed in a petri dish and allowed to stand for 14 days in a thermo-hygrostat (EYELA photostability tester LST-300, manufactured by Tokyo Rikakikai Co., Ltd.) set at a temperature of 35°C and a humidity of 75%.

[0042] <Evaluation of sugar precipitation> The presence or absence of sugar precipitation was visually confirmed 14 days after the start of the accelerated test. The results are shown in Tables 1 to 3.

[0043] <ΔL * Value, Δa * value, and Δb * Value Measurement> The dried vegetables were placed in a beaker and packed as flat as possible. Using a color difference meter (Konica Minolta, Inc., CR-410 color difference meter), the L * Value, a * value, and b* The measurements were taken three times before the start of the acceleration test and 14 days after the acceleration test, and the average value was calculated. * Value, Δa * value, and Δb * The value was calculated according to the following formula. Formula:ΔL * Value = [L after 14 days of acceleration test * value]-[L before the acceleration test starts * value] Δa * Value = [a after 14 days of acceleration test * value]-[a before the acceleration test starts * value] Δb * Value = [b after 14 days of acceleration test * value]-[b before the acceleration test starts * value] In addition, the more sugar that precipitates on the surface of the cabbage, the whiter it appears. * value becomes large. Therefore, L * A larger value indicates a whiter color. L before and after acceleration test * Value, a * value, and b * value, as well as ΔL * Value, Δa * value, and Δb * The values ​​are shown in Tables 1 to 3.

[0044] [Table 1]

[0045] [Table 2]

[0046] [Table 3]

[0047] From these results, no sugar precipitation was observed even after 14 days of the acceleration test at a temperature of 35°C and a humidity of 75°C for the dried vegetables of Examples 1 to 4 to which only trehalose was added, and the dried vegetables of Examples 5 to 12 to which trehalose was added in combination with other carbohydrates. Thus, by mixing blanched vegetables and trehalose and drying them, it became possible to suppress sugar precipitation even when the dried vegetables were stored in a poorly preservable container for a long time. Also, for the dried vegetables of Examples 1 to 12, the ΔL * value was also low. On the other hand, in Comparative Examples 1 to 7 to which one or two to four types of carbohydrates other than trehalose were added, sugar precipitation was observed on the surface of the cabbage after 14 days of the acceleration test, and the ΔL * value was also high.

[0048] <Experimental Example 2> The influence of the presence or absence of pH adjustment on sugar precipitation in dried vegetables was examined. As the pH adjuster, sodium hydrogen carbonate: baking soda (food additive) manufactured by Marufuku Chemical Co., Ltd. was used.

[0049] Examples 13 to 15 and Comparative Examples 8 to 12 Dried vegetables (cabbage) of Examples 13 to 15 and Comparative Examples 8 to 12 were obtained in the same manner as in Example 1, except that the carbohydrates and pH adjuster (sodium hydrogen carbonate) shown in Table 4 below were mixed in the amounts (parts by mass) shown in Table 4 below with the blanched cabbage cooled to less than 40°C and drained.

[0050] <pH Measurement> For the dried vegetables of Examples 13 to 15 and Comparative Examples 8 to 12 obtained, the pH of the 20-fold diluted aqueous solution was measured in the same manner as in Experimental Example 1 above. The results are shown in Table 4.

[0051] Acceleration Test An acceleration test was conducted for 14 days in the same manner as in Experimental Example 1 above on the dried vegetables obtained in Examples 13 to 15 and Comparative Examples 8 to 12. <Evaluation of Sugar Precipitation> The presence or absence of sugar precipitation was visually confirmed 14 days after the start of the acceleration test. The results are shown in Table 4.

[0052]

Table 4

[0053] From these results, when trehalose was added, sugar precipitation was not observed 14 days after the acceleration test, whether pH adjustment was performed (Example 15) or not (Examples 13 and 14). On the other hand, when glucose, lactose, or maltose was added (each of the above comparative examples), sugar precipitation was observed even when pH adjustment was carried out, and the results were the same as those without pH adjustment. In Comparative Example 12, since the pH was too high, many parts of the leaf veins had already turned brown at the stage after drying.

[0054] <Experimental Example 3> The influence of the difference in vegetables on sugar precipitation in dried vegetables was examined. Example 16 and Comparative Examples 13 to 14 Using chingensai instead of cabbage, dried vegetables (chingensai) of Example 16 and Comparative Examples 13 to 14 were obtained in the same manner as in Example 1 above, except that the saccharides described in Table 5 below were mixed in the amounts (parts by mass) described in Table 5 below.

[0055] <pH Measurement> For the obtained dried vegetables of Example 16 and Comparative Examples 13 to 14, the pH of the 20-fold diluted aqueous solution was measured in the same manner as in Experimental Example 1 above. The results are shown in Table 5.

[0056] Acceleration Test For the dried vegetables obtained in Example 16 and Comparative Examples 13 to 14, an acceleration test was conducted for 14 days in the same manner as in Experimental Example 1 above. <Evaluation of Sugar Precipitation> 14 days after the start of the acceleration test, the presence or absence of sugar precipitation was visually confirmed. The results are shown in Table 5.

[0057] <ΔL * Value, Δa * value, and Δb* Value Measurement> For the dried vegetables obtained in Example 16 and Comparative Examples 13 to 14, the L before and after the acceleration test was performed in the same manner as in Experimental Example 1. * Value, a * value, and b * Measure the value and ΔL * Value, Δa * value, and Δb * The values ​​were calculated, and the results are shown in Table 5.

[0058] [Table 5]

[0059] In Example 16, in which trehalose was added to bok choy, no sugar precipitation was observed 14 days after the accelerated test. * The value was also low. In Comparative Examples 13 and 14, in which sugars other than trehalose were added to bok choy, it was visually observed that the surface was white 14 days after the acceleration test. * The values ​​were higher than in Example 16.

[0060] In order to observe the condition of the vegetable surface in more detail, the dried vegetables (bok choy) of Example 16 and Comparative Example 13 were photographed at 200x magnification using a microscope (manufactured by Keyence Corporation, product name: VH-7000) before and 14 days after the acceleration test. A photograph of the dried vegetables of Example 16 before the acceleration test is shown in FIG. 1, and a photograph of the dried vegetables of Example 16 after the acceleration test is shown in FIG. 2. A photograph of the dried vegetables of Comparative Example 13 before the acceleration test is shown in FIG. 3, and a photograph of the dried vegetables of Comparative Example 13 after the acceleration test is shown in FIG. 4. As shown in Figure 2, no sugar precipitation was observed in the photograph (200x magnification) of the dried vegetables after the accelerated test of Example 16, but white sugar crystals were even visible in the photograph (200x magnification) of the dried vegetables after the accelerated test of Comparative Example 13 shown in Figure 4. These results show that the addition of trehalose to bok choy, a leafy vegetable like cabbage, suppresses sugar precipitation.

[0061] Here, for the dried vegetables (cabbage) of Example 1 and Comparative Example 1, photographs were taken at 200x magnification using a microscope (manufactured by Keyence Corporation, product name: VH-7000) before and 14 days after the acceleration test. Photographs of the dried vegetables of Example 1 before the acceleration test are shown in FIG. 5, and photographs of the dried vegetables of Example 1 after the acceleration test are shown in FIG. 6. Photographs of the dried vegetables of Comparative Example 1 before the acceleration test are shown in FIG. 7, and photographs of the dried vegetables of Comparative Example 1 after the acceleration test are shown in FIG. 8. As shown in Figure 6, no sugar precipitation was observed in the photograph (200x magnification) of the dried vegetables after the accelerated test of Example 1, but sugar precipitation was observed in the photograph (200x magnification) of the dried vegetables after the accelerated test of Comparative Example 1 shown in Figure 8.

[0062] <Experimental Example 4> A type of carbohydrate different from that used in Example 1 was used to examine the effect of the type of carbohydrate on sugar precipitation in dried vegetables. As the carbohydrates, in addition to the glucose, lactose, maltose, and trehalose used in Example 1, the following carbohydrates were used. α-Cyclodextrin: Celldex (registered trademark) A-100 manufactured by Nihon Shokuhin Kako Co., Ltd. β-Cyclodextrin: Celldex (registered trademark) B-100 manufactured by Nihon Shokuhin Kako Co., Ltd. Polysaccharide (DE9): SPD manufactured by Showa Sangyo Co., Ltd. Polysaccharides (DE23): VIANDEX-BH manufactured by Showa Sangyo Co., Ltd. Polysaccharides (DE30): PSK-M manufactured by Showa Sangyo Co., Ltd. DE (Dextrose Equivalent) is an index that shows how much starch has been broken down. The closer the DE is to 100, the closer it is to a monosaccharide state and the smaller the average molecular weight.

[0063] Examples 17 to 26 and Comparative Examples 15 to 17 The dried vegetables (cabbage) of Examples 17 to 26 and Comparative Examples 15 to 17 were obtained in the same manner as in Example 1 above, except that the cabbage was blanched, cooled to less than 40°C, and drained of its liquid, and mixed with the carbohydrates shown in Tables 6 to 7 below in the amounts shown in Tables 6 to 7 below.

[0064] Acceleration Test For the dried vegetables obtained in Examples 17 to 26 and Comparative Examples 15 to 17, an accelerated dehydration test was carried out for 14 days in the same manner as in Experimental Example 1 above.

[0065] <Evaluation of sugar precipitation> The surfaces of the vegetables were visually inspected immediately after drying. Then, 14 days after the start of the accelerated test, the presence or absence of sugar precipitation was visually inspected. The results are shown in Tables 6 and 7.

[0066] <ΔL * Value, Δa * value, and Δb * Value Measurement> For the dried vegetables of Examples 23 to 26, the L before and after the acceleration test was performed in the same manner as in Experimental Example 1. * Value, a * value, and b * Measure the value and ΔL * Value, Δa * value, and Δb * The values ​​were calculated, and the results are shown in Table 7.

[0067] [Table 6]

[0068] [Table 7]

[0069] From these results, sugar precipitation was not observed after 14 days of the accelerated test in the dried vegetables of Examples 17 to 22 to which α-cyclodextrin or β-cyclodextrin was added. Furthermore, sugar precipitation was not observed after 14 days of the accelerated test in the dried vegetables of Examples 23 and 25 to which α-cyclodextrin was added in combination with other sugars, and in the dried vegetables of Examples 24 and 26 to which α-cyclodextrin and trehalose were added in combination with other sugars. On the other hand, in Comparative Examples 15 to 17 in which polysaccharides other than cyclodextrin were added, it was confirmed by visual inspection immediately after drying that the vegetable surface was white. This showed that not all of the added carbohydrates penetrated into the cabbage leaves.

Claims

1. cutting the vegetables to obtain small pieces of vegetables; A step of mixing the vegetable obtained by blanching the small pieces of the vegetable with carbohydrates to obtain a vegetable containing carbohydrates; and The method includes a step of drying vegetables containing carbohydrates. A method for producing dried vegetables in which sugar precipitation is suppressed, The carbohydrate is trehalose and maltose; Cyclodextrin and maltose; or Contains trehalose, cyclodextrin and maltose, The carbohydrate is mixed in powder form with the blanched vegetables, The method does not include a freezing step between the step of obtaining the carbohydrate-containing vegetables and the step of drying the carbohydrate-containing vegetables, and The method for producing dried vegetables in which sugar precipitation is suppressed, wherein the pH of a 20-fold diluted aqueous solution of the dried vegetables is less than 7.

0.

2. The method for producing dried vegetables in which sugar precipitation is suppressed according to claim 1, wherein the blanched vegetables have a product temperature of less than 40°C.

3. The carbohydrate further includes at least one sugar selected from the group consisting of glucose and lactose. The method for producing dried vegetables in which sugar precipitation is suppressed according to claim 1.

4. The method for producing dried vegetables in which sugar precipitation is suppressed according to claim 1, wherein the amount of the carbohydrate added is 1 to 25 parts by mass per 100 parts by mass of the blanched vegetables.

5. The method for producing dried vegetables in which sugar precipitation is suppressed as described in claim 3, wherein the carbohydrate is a mixture containing trehalose, maltose, glucose and lactose.

6. CIE1976-L immediately after the production of the dried vegetables ＊ a ＊ b ＊ L in color system ＊ Value, CIE1976-L of dried vegetables after 14 days of storage at 35°C and 75% humidity ＊ a ＊ b ＊ L in color system ＊ The difference between the values ​​(ΔL ＊ The method for producing dried vegetables in which sugar precipitation is suppressed according to claim 1, wherein the sugar precipitation value is 2.0 or less.

7. A dried vegetable in which sugar precipitation is suppressed, obtained by the method for producing a dried vegetable in which sugar precipitation is suppressed according to any one of claims 1 to 6, The carbohydrate is trehalose and maltose; Cyclodextrin and maltose; or A dried vegetable in which sugar precipitation is inhibited, the mixture being a mixture containing trehalose, cyclodextrin and maltose.

8. cutting the vegetables to obtain small pieces of vegetables; A step of mixing the vegetable obtained by blanching the small pieces of the vegetable with carbohydrates to obtain a vegetable containing carbohydrates; and The method includes a step of drying vegetables containing carbohydrates. A method for inhibiting sugar precipitation in dried vegetables, comprising: The carbohydrate is trehalose and maltose; Cyclodextrin and maltose; or Contains trehalose, cyclodextrin and maltose, The carbohydrate is mixed in powder form with the blanched vegetables, The method does not include a freezing step between the step of obtaining the carbohydrate-containing vegetables and the step of drying the carbohydrate-containing vegetables, and The method for inhibiting precipitation of sugar in dried vegetables, wherein the dried vegetables have a pH of a 20-fold diluted aqueous solution of less than 7.0.

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