Reheatable gel food

Abstract

To provide a gel food exhibiting heat resistance, avoiding excessive hardening after reheating, and having suppressed water separation.SOLUTION: A gel food comprising modified konjac flour and processed starch, wherein a ratio of the modified konjac flour to the processed starch is 1:1.5-15, the gel food thus obtained being capable of reheating by microwave heating, steam convection oven heating, or the like immediately before serving after cooling through freezing or a chilled temperature range.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a reheatable gel food, particularly a gel food that is heat-resistant, does not become too hard even after reheating, and is inhibited from syneresis, and a composition used for preparing said gel food. [Background technology]

[0002] In the field of food processing, various gel foods are known, and gel foods having heat resistance that can withstand cooking or heating for extending shelf life are also known. Gel foods for people with chewing difficulties are also known as foods for medical and nursing care purposes. These foods are characterized by their easy chewing in the mouth, easy crushing hardness, and easy swallowing. These gel foods were handmade for each meal at nursing care facilities such as hospitals and nursing homes. However, due to the small number of patients and the need to shorten cooking time, hospitals and nursing homes have recently begun purchasing convenient pre-processed gel foods, and there is a demand for these foods to be heat-resistant during cooking and reheating.

[0003] Under these circumstances, konjac flour and glucomannan are used as heat-resistant gelling agents in various foods. Known examples of heatable foods containing konjac flour include processed food materials for nursing care (see Patent Document 1), which contain a gelling agent containing konjac flour and retain their original shape and hardness even when cooked at temperatures above 150°C. However, gel foods using konjac flour or glucomannan are known to lose water when frozen or heated, and to change in hardness when reheated after gelation, posing challenges when reheating or cooking the prepared gel foods. In particular, when gel foods are used as foods for the elderly or those with difficulty chewing, the change in hardness affects the diet of the eater, burdening the cook by requiring them to adjust their diet accordingly. Specifically, the texture becomes hard when cooked at high temperatures, such as by simmering or by exposing the food to high-temperature hot air from a microwave or reheating cart. Furthermore, there was also the problem that it was prone to syneresis when reheated.

[0004] Therefore, the present invention aims to provide a gel food that solves the conventional problems and a composition used for preparing said gel food, and presents a gel food that changes little in hardness (strength) even when reheated at high temperatures and that is less prone to syneresis, a method for producing the same, and a method for suppressing an increase in the gel strength of a gel food. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-018129 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-93975 [Patent Document 3] Japanese Patent Application Laid-Open No. 2012-165658 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a gel food that is heat-resistant, does not become too hard even after reheating, and is inhibited from syneresis, and a composition for preparing the gel food. [Means for solving the problem]

[0007] As a result of intensive research to solve the above problems, the inventors of the present invention found that these problems could be solved by blending modified konjac flour that has been subjected to a modification treatment with processed starch, and thus completed the present invention. More specifically, they found that by using modified konjac flour and processed starch together in a food product at a specific blend ratio, a gel-like food product can be obtained that does not become too hard even after reheating and that exhibits suppressed syneresis.

[0008] That is, the present invention is as follows. (1) A composition containing modified konjac flour and modified starch, with the modified starch being 1.5 to 15 parts by weight per 1 part by weight of modified konjac flour. (2) The composition according to (1), further comprising one or more of xanthan gum, agar, and locust bean gum. (3) A gel food containing modified konjac flour and processed starch, characterized in that the blending ratio of modified konjac flour to processed starch is 1:1.5 to 15. (4) A gel food according to (3), further comprising one or more of xanthan gum, agar, and locust bean gum. (5) The composition according to (1) above or the gelled food according to (3) above, characterized in that the modified starch is one or more crosslinked starches selected from the group consisting of hydroxypropylated phosphate crosslinked starch, phosphate crosslinked starch, phosphate monoesterified phosphate crosslinked starch, acetylated adipate crosslinked starch, acetylated oxidized crosslinked starch, or acetylated phosphate crosslinked starch. (6) The gel food according to (3) above, wherein the blending amount of the modified starch is 1.0 to 10.0% by mass. (7) The gel food according to (3) above, wherein the blending amount of the modified konjac flour is 0.3 to 5.0% by mass. (8) Hardness at 20°C: 5,000 to 60,000 N / m 2 The gel food according to (3) above, characterized in that: (9) A method for producing a gel food, characterized by mixing modified konjac flour and processed starch with water or food ingredients containing water, and heating the mixture to 80°C or higher. (10) A method for suppressing an increase in gel strength when a gel food using modified konjac flour and processed starch is reheated, wherein the modified konjac flour and processed starch are used in an amount of 1.5 to 15 parts by weight of processed starch per 1 part by weight of modified konjac flour. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a gelled food and a composition for preparing the same that are heat-resistant when reheated, do not become too hard after heating, are refrigerated and frozen, and exhibit reduced syneresis. Furthermore, by further blending a specific polysaccharide, it is possible to adjust the viscosity of a solution or sol containing the composition of the present invention before gelation, which makes it easier to handle the gelled food during production and allows the production of a gelled food with an improved gel texture. DETAILED DESCRIPTION OF THE INVENTION

[0010] The composition of the present invention is a composition for preparing a gelled food containing modified konjac flour and processed starch. The composition contains modified konjac flour and processed starch in an amount of 1.5 to 15 parts by weight, preferably 3.5 to 12 parts by weight, more preferably 5.5 to 12 parts by weight, and even more preferably 8.5 to 12 parts by weight, of processed starch per part by weight of modified konjac flour. If the modified konjac flour and processed starch are outside these ranges, the gel formed when the gelled food is prepared will be insufficient, or the gel will become too hard when reheated, which is undesirable.

[0011] The modified konjac flour of the present invention refers to a konjac flour that has been modified from conventionally known konjac flour to allow for easy formation of a gel without the need for pH adjustment, and differs from ordinary konjac flour, which requires an alkaline agent for dissolution and gelation or requires a long time for swelling. Such modified konjac flour can be obtained, for example, by modifying the physical properties of konjac flour by heat-treating the konjac flour with an alkaline solution while suppressing its swelling, or by adding konjac flour to an alcohol solution to semi-swell the konjac flour, and then adding an alkaline solution to the alcohol solution containing the konjac flour to cause a reaction and modify the konjac flour. The modified konjac flour obtained in this manner swells before use in a shorter time than conventional konjac flour, for example, within 12 hours, 6 hours, 3 hours, or 1 hour, or even if swelling is not required. It can be dispersed in water without the need for an alkali agent to form a dispersion, and then gelled by heating or stirring, thereby easily producing a gel with high gel strength and low pH. Such modified konjac flour can be produced by methods such as those described in JP 2011-072304 and JP 2021-078448, or by other manufacturing methods, as long as it has similar water dispersibility and gelling ability without the need for alkali. Commercially available modified konjac flours include "Ultramannan" (Ina Food Industry Co., Ltd.) and "Magic Mannan" (Sansho Co., Ltd.). The amount of modified konjac flour to be added is not particularly limited, but is preferably 0.3 to 5.0% by mass, and more preferably 0.5 to 3.5% by mass, of the gelled food.

[0012] The modified starch in the present invention is obtained by chemically modifying starch extracted from potatoes, corn, tapioca, etc., and specific examples thereof include starch acetate, oxidized starch, hydroxypropyl starch, hydroxypropyl phosphate cross-linked starch, phosphate cross-linked starch, phosphated starch, phosphate monoesterified phosphate cross-linked starch, acetylated phosphate cross-linked starch, acetylated adipate cross-linked starch, acetylated oxidized cross-linked starch, and sodium octenyl succinate starch. Cross-linked starch, which is starch obtained by treating raw starch with a cross-linking agent and chemically cross-linking it, is preferred to achieve the effects of the present invention. Cross-linked starch in which the substituents have been esterified or etherified is more preferred. Specific examples of particularly preferred examples include hydroxypropyl phosphate cross-linked starch, phosphate cross-linked starch, phosphate monoesterified phosphate cross-linked starch, acetylated adipate cross-linked starch, acetylated oxidized cross-linked starch, and acetylated phosphate cross-linked starch. The amount of modified starch added is not particularly limited, but is generally 1.0 to 10.0% by mass, preferably 2.0 to 8.0% by mass, and more preferably 2.0 to 6.0% by mass in the gelled food.

[0013] In the present invention, other polysaccharides can be used in the composition or gel food of the present invention to adjust the texture and shape retention of the gel food. Examples include xanthan gum, guar gum, locust bean gum, tara gum, carrageenan, glucomannan, native gellan gum, deacylated gellan gum, tamarind seed gum, pectin, gelatin, gum arabic, curdlan, cellulose, alginic acid, agar, etc. In the present invention, one or a combination of two or more of these thickening polysaccharides can be suitably used, and among these, the use of one or more of xanthan gum, agar, and locust bean gum is particularly preferred for gel foods for the elderly and those who have difficulty chewing. The amount of these polysaccharides used is not particularly limited, but can be, for example, 0.01 to 0.5% by mass each in the gel food.

[0014] The composition of the present invention may be used in combination with food ingredients such as seasonings, spices, and sweeteners, as well as dextrin, oils and fats, food additives, and food ingredients including food paste, or food ingredients for people with difficulty chewing, including food paste, for purposes such as improving the flavor, texture, and shelf life of the gel food, as long as the effects of the invention are not impaired. Food pastes are water-containing paste-like foods made from vegetables, fruits, seafood, meat, eggs, dairy products, or processed products thereof, which are either raw or cooked and then finely divided into small pieces using conventional methods such as crushing, grinding, or straining to eliminate large lumps. In addition to food pastes, food ingredients for people with difficulty chewing may also contain animal and vegetable oils and fats, thickening polysaccharides other than modified konjac flour and processed starch, water-soluble dietary fiber, carbohydrates such as starch syrup and dextrin, preservatives, flavorings, and colorings, as appropriate.

[0015] The gelled food of the present invention may be prepared by mixing the composition of the present invention containing the above-mentioned modified konjac flour and processed starch with water or a food ingredient containing water, or the modified konjac flour and processed starch may be prepared separately and mixed with water or a food ingredient containing water, as long as the blending ratio of the modified konjac flour to the processed starch is 1:1.5 to 15, preferably 1:3.5 to 12, more preferably 1:5.5 to 12, and even more preferably 1:8.5 to 12.

[0016] The gel food of the present invention is a gel food containing modified konjac flour, processed starch, and water, and is a gel food containing modified konjac flour, processed starch, and food paste, or a gel food containing modified konjac flour, processed starch, and food paste and one or more selected from the group consisting of animal and vegetable oils and fats, carbohydrates other than modified konjac flour and processed starch, preservatives, flavorings, coloring agents, etc. ... It can also be said to relate to a gel-type food for people who have difficulty chewing that contains food ingredients for people who have difficulty chewing, including konjac flour, processed starch, and food paste, or a gel-type food for people who have difficulty chewing that contains food ingredients for people who have difficulty chewing that are composed of modified konjac flour, processed starch, and food paste and one or more ingredients selected from the group consisting of animal and vegetable oils and fats, carbohydrates other than modified konjac flour and processed starch, preservatives, flavorings, coloring agents, etc.

[0017] Examples of the animal and vegetable oils include vegetable oils such as olive oil, palm oil, palm kernel oil, rapeseed oil, coconut oil, peanut oil, safflower oil, sunflower oil, cottonseed oil, corn oil, sesame oil, soybean oil, rice oil, and cacao butter, as well as animal oils such as beef tallow, lard, fish oil, whale oil, and milk fat. Examples of preservatives include antibacterial organic acids and salts thereof, amino acids such as glycine, proteins such as lysozyme and protamine, and antioxidants such as L-ascorbic acid and tocopherol.

[0018] The composition of the present invention containing the above-mentioned modified konjac flour and processed starch is mixed with food ingredients containing water or food paste when producing a gelled food product, and is contained in the gelled food product. The composition of the present invention may be dispersed in water in advance, and seasonings or the like may be added to the dispersion to form a gelled food product, or the dispersion may be mixed with separately prepared food ingredients, or may be directly mixed with food ingredients containing water. Similarly, when the modified konjac flour and processed starch are used separately, rather than as the composition of the present invention, they may be mixed with water or food ingredients and contained in the gelled food product.

[0019] The gel food of the present invention is not particularly limited, but the hardness at a product temperature of 20°C is preferably 5000 to 60000 N / m 2 For use as a food for people with difficulty in chewing, the strength of the food may be preferably 5000 to 50000 N / m 2 , more preferably 5000 to 20000 N / m 2 Here, the hardness of the gel food is indicated as the result of measurement using a device capable of measuring the compressive stress of a substance, such as a texture analyzer or creep meter, specifically, by using a sample size of 40 mmφ x 15 mm height with a cylindrical plunger of 20 mm diameter at a compression rate of 10 mm / sec with a clearance of 5 mm.

[0020] A detailed example of the method for producing a gel food product of the present invention involves appropriately mixing a food ingredient containing a food paste to be used as the gel food material with modified konjac flour, processed starch, and water, filling the mixture into a cup or food mold, and then heating it to 80°C or higher, preferably 90°C or higher. Heating the ingredients filled into a cup or food mold at 80°C or higher in this way causes the modified konjac flour to gel, resulting in a gel food product with a solidified food paste. The gel food product thus obtained can be refrigerated or frozen, and, because it is heat-resistant, can also be cooked. Furthermore, after freezing or cooling in the chilled zone, it can be reheated in a microwave oven, steam convection oven, or reheating cart before serving, and its hardness remains stable even after such reheating.

[0021] The gelled food of the present invention has the advantage that, after heat solidification for gelation, the shape of the gelled food is not easily distorted by heating, even when reheated for cooking or to extend shelf life. Furthermore, the shape is not easily distorted not only when refrigerated but also when frozen, thawed and reheated to eating temperature, and the syneresis that generally occurs with gelled foods after refrigeration or freezing is minimal.

[0022] Furthermore, when the gel food of the present invention is heated and molded in a cup or food mold, refrigerated or frozen, and then returned to room temperature, the amount of water contained in the gel food can be determined by the fact that the water that is not contained in the shape-retaining food gel spreads onto the plate when the gel food is served on a plate or the like.

[0023] Furthermore, the present invention provides a method for suppressing an increase in gel strength when a gel food containing modified konjac flour and processed starch is reheated. This method is characterized by setting the blending ratio of modified konjac flour to processed starch in a gel food containing modified konjac flour and processed starch to 1:1.5 to 15, preferably 1:3.5 to 12, more preferably 1:5.5 to 12, and even more preferably 1:8.5 to 12. By using this blending ratio, the resulting gel food has the advantage of suppressing an increase in hardness and not becoming too hard, even when reheated in a steam convection oven, microwave oven, reheating cart, etc.

[0024] The present invention will be specifically explained below with reference to examples, but the technical scope of the present invention is not limited to these examples. The modified konjac flour used was "Ultramannan G" (which can swell within one hour) from Ina Food Industry Co., Ltd., and the processed starch used was a commercially available acetylated phosphate cross-linked starch as a representative example of cross-linked starch. For comparative examples, the following were used: "Shirayuki Special Grade" konjac flour from Ogino Shoten Co., Ltd.; and "Leolex RS" glucomannan from Shimizu Chemical Co., Ltd., a commercially available glucomannan that requires no swelling or requires an alkaline agent for gelation due to its unmodified nature, but which is commercially available for short-term or no swelling.

[0025] <Examples 1 and 2> Modified konjac flour, modified starch, and water were prepared according to the formulations of Examples 1 and 2 listed in Table 1. These were mixed in a mixer and then filled into food cups in 40g portions. The modified konjac flour was used without any swelling time (0 hours). The cups were heat-sealed with film, heated in a steam convection oven at 95°C for 30 minutes, and then cooled to below 10°C in a blast chiller to obtain a gel food product.

[0026] <Comparative Examples 1 and 2> As comparative examples, gel foods were obtained in the same manner as in the examples, except that no processed starch was used (Comparative Example 1) and 1 part by weight of processed starch was used for every 1 part by weight of modified konjac powder (Comparative Example 2). <Comparative Examples 3 to 6> Furthermore, as a comparative example, the modified konjac flour of Example 2 was replaced with regular konjac flour "Shiroyuki Special Grade," and a gelled food was obtained by the same method as in Example 2 (Comparative Example 3). Similarly, the modified konjac flour of Example 2 was replaced with "Leolex RS," and a gelled food was obtained by the same method as in Example 2, except that an alkaline agent for gelling (calcium hydroxide) was added during blending in the mixer. This gelled food was designated Comparative Example 4. When using the same amount of Leolex RS as modified konjac flour or regular konjac flour, the viscosity was very high when blended with water in a blender, making it difficult to work with. Therefore, the ratio of modified starch was the same as in the examples, and the blending amount was reduced for testing. The blending composition is shown in Table 1.

[0027] [Table 1]

[0028] For each of the gel foods of Examples 1 and 2 and Comparative Examples 1, 2, and 4, "heat resistance" was evaluated based on the shape after reheating, and "reheat resistance" and "freeze resistance" were evaluated comprehensively by combining evaluations of changes in hardness, texture, and syneresis. Note that for the formulation of Comparative Example 3, when it was removed from the food cup after heating in a steam convection oven and cooling in a blast chiller, it did not gel, and although it had some cohesion, it was a sticky paste-like substance, and could not be used for the subsequent evaluation tests as a gel food. The heat resistance evaluation was described in detail below. The resulting gel food was removed from the food cup and cut into cylindrical shapes measuring 40 mm in diameter and 15 mm in height. Each shape was then identical before the test, and the food was then placed on a plate for the heating test. The heating method was microwave heating (500 W for 1 minute), after which the shape was visually evaluated. Alternatively, instead of microwave heating, the food was heated in a steam convection oven (also called a "steam oven") (hot air 120°C for 30 minutes), and the shape was visually evaluated in the same manner as for microwave heating. The evaluation criteria were ascertaining whether the shape was maintained after heating, with a rating of ○ if the gel retained its shape after heating, a rating of △ if it slightly lost its shape but was still able to stand on its own, and an × if it lost its shape.

[0029] Next, we will explain the details of the evaluation of "reheat resistance." "Reheat resistance" is a comprehensive evaluation of the syneresis, changes in hardness, and changes in texture of the gel food obtained when it is reheated (hot air 120°C, 30 minutes) in a steam convection oven while still in the food cup. Regarding water release, when the reheated gel food was cooled to room temperature and removed from the food cup, a rating of ○ was given if almost no water spread, a rating of △ if a small amount of water leaked out but was within the acceptable range, and an × if a large amount of water spread onto the plate. Hardness was measured by adjusting the sample gel food to 20°C, removing it from the food cup, and using a creep meter. The change in hardness of the gel food after reheating was confirmed using the gel food before reheating as the standard. If the change in hardness was about ±20% compared to the standard hardness measurement, it can be said that there is little change in hardness, and in particular, if it does not exceed +20%, it can be said that the food has not become too hard due to reheating. The changes in texture were evaluated by a trained panel and their comments were recorded regarding the differences from before reheating.

[0030] Next, we will explain the details of the evaluation of "freeze resistance." "Freeze resistance" is a comprehensive evaluation of syneresis, changes in hardness, and changes in texture after the obtained gel food is frozen overnight while still in the food cup, and then thawed by heating in a steam convection oven at 120°C for 30 minutes. The evaluation criteria for syneresis, the method for measuring hardness, and the evaluation of texture are the same as for "reheat resistance." The results are shown in Table 2.

[0031] [Table 2]

[0032] As can be seen from the results in Table 2, the gel foods of Examples 1 and 2 were heat resistant when reheated, syneresis was suppressed, and the degree of change in hardness was suppressed compared to Comparative Examples 1 and 2. Syneresis was also suppressed compared to Comparative Example 4.

[0033] <Examples 3 to 5> Gel foods were prepared according to the formulations of Examples 3 to 5 shown in Table 3. The same procedures as in Examples 1 and 2 were carried out except that xanthan gum was added to water together with modified konjac flour and modified starch, and then mixed in a mixer.

[0034] <Comparative Examples 5 and 6> As comparative examples, gel foods were obtained in the same manner as in Examples 3 to 5, except that no modified starch was used (Comparative Example 5) and that 1 part by weight of modified starch was used per 1 part by weight of modified konjac flour (Comparative Example 6). The evaluation results of the obtained gel foods are shown in Table 4.

[0035] [Table 3]

[0036] [Table 4]

[0037] As can be seen from the results in Table 4, the gel foods of Examples 3 to 5 were more heat-resistant and reheat-resistant than the gel foods of Comparative Examples 5 and 6. Furthermore, the gel foods of Examples 3 to 5, which contained xanthan gum, had a moderate viscosity of the pre-gelling solution after being mixed in a mixer, and were able to produce gels. Furthermore, the texture of the gel foods was softer and more elastic than the strong elastic texture of konjac, making them suitable for people who have difficulty swallowing and chewing.

[0038] <Examples 6 and 7> Carrot paste-containing gel foods were prepared according to the formulation shown in Table 5. A commercially available heated carrot paste was used, and the modified konjac flour, processed starch, and optionally other ingredients and water were premixed in a mixer, after which the paste was added and further stirred and mixed in the mixer. The procedure was the same as in Examples 1 and 2, except that the heated carrot paste was blended with any other ingredients. The evaluation results of the obtained gel foods are shown in Table 6.

[0039] [Table 5]

[0040] [Table 6]

[0041] As can be seen from the results in Table 6, the gel foods of Examples 6 and 7 containing carrot paste were heat resistant when reheated, had little syneresis, and showed little change in hardness. Furthermore, Example 6 had a mousse-like texture, and Example 7 had a jelly-like texture, which was also good in terms of texture.

[0042] The hardness of the gel foods of Examples 6 and 7 was 20,000 N / m before and after reheating. 2 The hardness was below 100g, which was suitable for use as food for people with difficulty in chewing. [Industrial Applicability]

[0043] The gel food of the present invention does not harden too much when reheated, syneresis is suppressed, and changes in hardness are suppressed, which allows for a wider range of applications of gel foods. Furthermore, the gel food of the present invention can also be used as a food for people who have difficulty chewing, and has industrial applicability in the fields of medical care and nursing.

Claims

1. A composition comprising modified konjac flour and modified starch, with the modified starch being 1.5 to 15 parts by weight per part by weight of the modified konjac flour.

2. The composition according to claim 1, further comprising one or more of xanthan gum, agar, and locust bean gum.

3. The gel food contains modified konjac flour and processed starch, characterized in that the blending ratio of the modified konjac flour to the processed starch is 1:1.5 to 15.

4. 4. The gel food according to claim 3, further comprising at least one of xanthan gum, agar, and locust bean gum.

5. 4. The composition according to claim 1 or the gelled food according to claim 3, wherein the modified starch is one or more crosslinked starches selected from the group consisting of hydroxypropylated phosphate crosslinked starch, phosphate crosslinked starch, phosphate monoesterified phosphate crosslinked starch, acetylated adipate crosslinked starch, acetylated oxidized crosslinked starch, and acetylated phosphate crosslinked starch.

6. 4. The gel food according to claim 3, wherein the amount of the modified starch blended is 1.0 to 10.0% by mass.

7. 4. The gel food according to claim 3, wherein the amount of modified konjac flour blended is 0.3 to 5.0% by mass.

8. Hardness at 20°C is 5,000 to 60,000 N / m ２ 4. The gel food according to claim 3, wherein

9. A method for producing a gel food, comprising mixing modified konjac flour and processed starch with water or a food ingredient containing water, and heating the mixture to 80°C or higher.

10. A method for suppressing an increase in gel strength when a gel food using modified konjac flour and processed starch is reheated, in which the modified konjac flour and processed starch are used in an amount of 1.5 to 15 parts by weight of processed starch per 1 part by weight of modified konjac flour.

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