Cooked egg product and its manufacturing method

Abstract

To provide an egg cooked product having at least one of the characteristics among having a juicy feeling, being reduced in a raw smell of an egg, having a soft texture, and imparting no water-separation feeling after time elapsing or being thawed; and a method of producing the egg cooked product capable of producing the egg cooked product having such characteristics even if a cook does not have expertise.SOLUTION: A cooked product of poultry egg includes fructan having a weight average molecular weight of 500 to 4,000, the fructan dissolved therein, and includes no whey. A method of producing the cooked product of poultry egg includes the steps of: preparing an egg liquid from a poultry egg; preparing fructan-containing egg liquid by dissolving the fructan, having the weight average molecular weight of 500 to 4,000 and including no whey, into the egg liquid; and coagulating at least part of the fructan-containing egg liquid by heating the liquid.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a cooked product made from bird eggs (hereinafter, bird eggs may also be simply referred to as "eggs") that is excellent in terms of texture, flavor, and / or water-releasing property, and to a method for producing the same. [Background technology]

[0002] Eggs are an excellent food ingredient that is supplied stably, and egg dishes are popular among many people, but the texture of egg dishes served after cooking can easily change depending on the heating temperature, cooking time, stirring method during cooking, etc., and a chef's skilled techniques are required to serve eggs with the soft, fluffy or creamy texture that is generally considered delicious. In addition, egg dishes tend to aggregate and solidify due to the residual heat after cooking and the passage of time, and the fluffy and creamy texture is only maintained for a short period of time. For this reason, it is difficult to cook large quantities of eggs, and in the food service industry, such as restaurants, eggs are sometimes cooked for each order.

[0003] Fructans are polymers of fructose linked by fructosidic bonds and are present in various plants as storage carbohydrates. In particular, inulin, a polymerized fructan found in chicory and Jerusalem artichoke, is becoming increasingly used as an important soluble dietary fiber.

[0004] Inulin is known to be indigestible, and therefore delivered to the large intestine, where it contributes to the proliferation of intestinal bacteria, especially the beneficial bifidobacteria. It is also known to be low in calories and to have the effect of keeping the GI value low.

[0005] Various uses for inulin have been investigated, and a paste made from a highly concentrated solution is used to replace fat in some foods because of its thick, mild taste, which is similar to lard. It is also known to have the effect of masking various bitternesses.

[0006] Patent document 1 states that adding inulin to heat-sterilized or frozen eggs makes it less likely for denaturation such as cloudy egg whites, gelling of egg yolks, or grainy texture to occur, but does not disclose whether the texture and taste are improved when the eggs are heated.

[0007] Patent Document 2 describes cooked egg products such as scrambled eggs, omelets, and rolled eggs, to which an oil-in-water emulsion with a total oil content of 5 to 50% by weight and adjusted to a pH of 4.0 to 6.8 has been added. The addition of this emulsion imparts a sufficient milky taste and rich flavor, while also producing a fluffy, creamy, soft texture without requiring the skill of a cook, and the texture can be maintained even after one hour has passed, but the addition of high-calorie lipids makes it difficult to use in low-calorie, healthy foods. In addition, Patent Document 2 lists milk, mayonnaise, and butter as additives for obtaining fluffy omelets.

[0008] Patent Document 3 describes a composition for enhancing the richness of eggs, which is obtained by adding trehalose to desugared liquid eggs and spray drying them. This composition does not solidify even when sterilized by heating, and there is no deterioration in flavor or roughness.

[0009] In addition, Non-Patent Document 1 states that the social welfare corporation Suiseikai's special nursing home for the elderly, Obihiro Keiseien The provided recipe for fried eggs is given using eggs, whey inulin cream, salt, a gelling agent, and oil. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2008-206399 A [Patent Document 2] JP 2018-143167 A [Patent Document 3] JP 2005-000014 A [Non-patent literature]

[0011] [Non-Patent Document 1] Tokachi ABC Project "Recipes using whey inulin cream", [Retrieved September 23, 2020], Internet <URL: http: / / www.tokachi-zaidan.jp / t-cityarea_new / recipe / kaigo01.html> Summary of the Invention [Problem to be solved by the invention]

[0012] The object of the present invention is to a) Juicy b) The fishy smell of eggs is reduced. c) It has a fluffy, soft texture; and d) The texture remains the same even after time has passed or after being frozen and thawed. The present invention aims to provide a cooked egg product having at least one of the following characteristics:

[0013] Another object of the present invention is to provide a method for producing a cooked egg product, which allows a cook without skilled techniques to produce a cooked egg product having the above-mentioned properties. [Means for solving the problem]

[0014] The present invention relates to a cooked egg product containing dissolved fructan having a weight-average molecular weight of 500 to 4,000, which does not contain whey.

[0015] The present invention also provides a method for producing a cooked egg product, comprising the steps of preparing liquid egg from eggs, dissolving whey-free fructan having a weight-average molecular weight of 500 to 4000 in the egg liquid to prepare a fructan-containing egg liquid, and heating the fructan-containing egg liquid to solidify at least a portion of it. Effect of the Invention

[0016] According to the cooked egg product of the present invention, a) Juicy b) The fishy smell of eggs is reduced. c) It has a fluffy, soft texture; and d) The texture remains the same even after time has passed or after being frozen and thawed. The effect of having at least one of the following characteristics is obtained. Furthermore, the method for producing a cooked egg product of the present invention has the advantage that a cooked egg product having the above-mentioned properties can be obtained even if the cook does not have a high level of skill. [Brief description of the drawings]

[0017] [Figure 1] 1 is a photograph showing scrambled eggs obtained in Comparative Example 1 after heating for 90 seconds. [Diagram 2] 1 is a photograph showing scrambled eggs obtained in Example 1 after heating for 90 seconds. [Diagram 3] 1 is a photograph showing scrambled eggs obtained in Example 2 after heating for 90 seconds. [Figure 4] 1 is a photograph showing scrambled eggs obtained in Example 3 after heating for 90 seconds. [Diagram 5] 1 is a photograph showing scrambled eggs obtained in Example 4 after heating for 120 seconds. [Figure 6] 1 is a photograph showing scrambled eggs obtained in Example 5 after heating for 120 seconds. [Figure 7] 1 is a photograph showing a cross section of the thawed omelet obtained in Comparative Example 2. [Figure 8] 1 is a photograph showing a cross section of the thawed omelet obtained in Example 6. [Figure 9] 1 is a photograph showing a cross section of the thawed omelet obtained in Example 7. [Figure 10] 1 is a photograph showing a cross section of the thawed omelet obtained in Example 8. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The present invention relates to a cooked egg product that does not contain whey and contains dissolved fructans having a weight-average molecular weight of 500 to 4000. Whey is also called "whey" or "whey".

[0019] The fructan used in the cooked food of the present invention is a polymer made up of fructose monomers linked by fructosidic bonds. Natural fructosidic bonds include 1,2-fructosidic bonds and 1,6-fructosidic bonds, and linear and branched fructans exist depending on the combination of these bonds.

[0020] The linear fructan used in the present invention is preferably inulin. Inulin is known to be present in the rhizomes of Asteraceae plants, and inulin extracted from chicory is the most widely used. In addition, this linear fructan can also be enzymatically synthesized and is commercially available as a food ingredient, so it can be used in the present invention.

[0021] On the other hand, branched fructans are often found in plants of the lily family, and agave inulin extracted from agave is widely used as a food, and is also used in the present invention.

[0022] The fructan used in the present invention may be either linear or branched, but inulin with a linear molecular weight fractionated to a certain extent is particularly preferred. As such, inulin extracted from chicory is the most preferred in terms of stable supply.

[0023] The weight-average molecular weight of the fructan used in the present invention is preferably in the range of 500 to 4000, more preferably 500 to 1500, and most preferably 800 to 1500. When a low molecular weight fructan is used, a smaller amount can be used to obtain a desired coagulation, and the higher the molecular weight, the more the amount required. On the other hand, when the molecular weight is low, the fructan itself has a sweet taste, so it may not be suitable for use.

[0024] The amount of fructan used in the present invention is generally in the range of 0.5 to 20 parts by mass, based on 100 parts by mass of the amount of eggs used. The range of the amount of fructan added to obtain a higher effect is also related to the molecular weight of the fructan used. As a guideline, when using fructan with a molecular weight lower than 1500, it is 0.5 to 10 parts by mass, and when using fructan with a molecular weight of 1500 to 4000, it is 0.5 to 5 parts by mass.

[0025] In the present invention, the addition of fructan slows down the thermal changes of eggs, which normally proceed rapidly, and the effect of fructan makes it difficult for water to separate. In particular, the effect of slowing down thermal changes is stronger with fructans with lower molecular weights, and the effect can be obtained even with a smaller amount of fructan added.

[0026] The eggs used in the present invention are avian eggs, such as chicken eggs, quail eggs, and duck eggs.

[0027] The eggs used in the present invention may be whole eggs or a part of them, or may be only egg yolks, only egg whites, or a mixture of egg yolks and egg whites in any ratio. Egg products such as frozen eggs, sweetened eggs, and composition-adjusted eggs may also be used.

[0028] The fructan is dissolved in the cooked food of the present invention, that is, the fructan is present in a dissolved state in the water contained in the cooked food of the present invention.

[0029] The cooked food of the present invention may have a region in which the fructan is dissolved. For example, even if the fructan is no longer dissolved in a part of the cooked food due to the loss of moisture in the part of the cooked food, so long as there is another region in which the fructan is dissolved, the cooked food of the present invention is still a cooked food of the present invention.

[0030] However, it is preferable that the fructan in the cooked food of the present invention is dissolved at a uniform concentration throughout the cooked food so that the texture is uniform.

[0031] The term "heating" in the case of the cooked food of the present invention means heating to a degree that causes coagulation of at least a part of the egg. That is, the cooked food of the present invention may be a food in which the egg is heat-coagulated in part or in whole.

[0032] Here, egg coagulation refers to the process in which eggs become solid and lose their fluidity. The degree of coagulation is not important as long as it is visible to the human eye. Egg yolks usually begin to coagulate at around 65°C and are completely coagulated at 75°C or higher, while egg whites usually begin to coagulate at around 60°C and are completely coagulated at 80°C or higher.

[0033] Furthermore, the term "cooked product" is used in this specification, but this term is expressed by a typical example of the heating operation of eggs, and is synonymous with "heat-processed product," "heat-treated product," "heat-coagulated product," or "heat-denatured product," and all of these are included in the concept of the cooked product of the present invention as long as they contain the above-mentioned part of the egg that has been heat-coagulated. Therefore, the cooked product of the present invention is not limited to those produced using cooking utensils or kitchen equipment, but also includes those produced at the time of sale at food factories, research facilities, and food stores.

[0034] Common cooking methods include frying pan heating, microwave heating, pot heating, and hot water bath heating.

[0035] In addition to eggs, the cooked food of the present invention may or may not contain dairy products such as cheese, butter, milk, and cream, vegetables such as tomatoes and onions, food additives for nutritional value, food additives for improving storage stability, and food additives for improving texture (e.g., gelling agents).

[0036] Examples of cooked eggs of the present invention include scrambled eggs, omelets, and tamagoyaki.

[0037] The present invention also provides a method for producing a cooked egg product, comprising the steps of preparing liquid egg from eggs, dissolving whey-free fructan having a weight-average molecular weight of 500 to 4000 in the egg liquid to prepare a fructan-containing egg liquid, and heating the fructan-containing egg liquid to solidify at least a portion of it.

[0038] The definitions, specific examples, and preferred examples of "egg" and "fructan", as well as "heating", "coagulation", "cooking", and "cooked products" used in the manufacturing method of the present invention are all the same as those described above for the cooked products of the present invention.

[0039] The "liquid egg" in the production method of the present invention can be prepared by cracking the eggs. The eggs can be cracked manually or by using an egg cracking machine. The cracked eggs can be automatically separated into egg yolk and egg white. If necessary, a filtration step may be added to remove small pieces of eggshell, chalaza, vitelline membrane, etc. When such a filtration step is performed, it is preferable to perform the filtration while appropriately cooling the liquid egg.

[0040] Usually, the liquid egg is homogenized by mixing, but the degree of homogenization varies depending on the cooked food to be produced, and insufficient homogenization may be preferable. Liquid egg may also be subjected to a pasteurization process that does not cause coagulation by heating.

[0041] The step of dissolving fructan in the egg liquid to prepare fructan-containing egg liquid may be performed manually or by using a fructan feed device or a stirring device, as long as the egg liquid in which the fructan is dissolved can be obtained. It is preferable that the fructan is dissolved uniformly in the liquid egg, but as long as the fructan is dissolved in at least a part of the liquid egg, it is included in the scope of the production method of the present invention.

[0042] The step of heating the fructan-containing egg liquid to at least partially solidify it may be carried out in a stationary state or with occasional or constant stirring.

[0043] The manufacturing method of the present invention includes a step of preparing liquid egg from eggs, a step of preparing fructan-containing egg liquid, and a step of heating and coagulating the fructan-containing egg liquid, and these steps are usually performed in the order listed.

[0044] However, it is also possible to carry out a step of dissolving fructan in liquid egg while carrying out a step of preparing the liquid egg, such as a stirring operation, or to carry out a step of adding fructan while carrying out a step of heating it, and these are also included in the scope of the manufacturing method of the present invention. EXAMPLES

[0045] In the following examples of the present invention, the following evaluation methods were employed. (1) Weight average molecular weight: Measured by gel filtration chromatography under the following conditions. Liquid chromatograph: Shimadzu Prominence, detector: RID-10A, column: Tosoh TSKgel G2500WXL, mobile phase: water.

[0046] (2) Flavor evaluation: A panel of 5 or 6 people evaluated the flavor of the food. Cooked foods without added inulin were used as a control, and cooked foods with a specified amount of added inulin were evaluated. The evaluation criteria were as follows: Moisture: Moist 2, slightly moist 1, almost the same 0 Fluffiness Fluffy 2, slightly fluffy 1, almost the same 0 Odor: Weaker 2, slightly weaker 1, almost the same 0 Texture: Very juicy 2, Slightly juicy 1, Almost the same 0 For these items, the snacks were evaluated 15 minutes and 2 hours after production, as well as after being frozen for one week and thawed at room temperature, and the average scores were calculated.

[0047] (3) Freezing resistance evaluation: Tamagoyaki (see recipe below) was made, wrapped and frozen. Thereafter, the meat was thawed at room temperature and the tissue condition and flavor were evaluated by cross-sectional observation. (4) Scrambled egg production Whole eggs, inulin, butter, and salt were mixed according to the composition shown in Table 1-3 to prepare a scrambled egg stock solution. This was stirred in a ring placed on a frying pan heated to 120°C. The cooking time was measured as a guide to processability by video recording. (5) Manufacture of rolled omelets Whole chicken eggs, stock, sugar, and inulin were mixed according to the compositions shown in Tables 4 and 5 to prepare a base liquid for tamagoyaki. The tamagoyaki pan was heated to about 120°C, and half of the liquid was added at a time and rolled up while cooking to prepare tamagoyaki. For the rolled omelet, a sensory test was carried out using the method (2) above.

[0048] [Examples 1 to 5, Comparative Example 1] Scrambled eggs having the compositions shown in Table 1-3 were produced as Comparative Example 1 and Examples 1 to 5, and the results are summarized in Table 1-3. The scrambled eggs of Examples 1 to 5 maintained a thicker texture than the scrambled eggs of Comparative Example 1, which did not contain inulin. In addition, the cooking time was not too short, which made it difficult to control the target product, and sufficient processability was ensured.

[0049] [Table 1]

[0050] [Table 2]

[0051] [Table 3]

[0052] [Examples 6 to 8, Comparative Example 2] As Comparative Example 2 and Examples 6 to 8, omelet products having the compositions shown in Tables 4 and 5 were produced and frozen. The thawed products were then evaluated by the sensory test described in (2). The results are summarized in Tables 4 and 5. The rolled eggs of Examples 6 to 8 had less egg odor and maintained a juicy texture compared to the rolled egg of Comparative Example 2, which did not contain inulin.

[0053] Furthermore, when the omelet of Comparative Example 2 was observed after thawing, many coarse holes were found on its cross section, whereas the omelets of Examples 6 to 8 had relatively dense cross sections even after thawing.

[0054] [Table 4]

[0055] [Table 5] [Industrial Applicability]

[0056] The present invention is applicable to, for example, a manufacturing industry that produces cooked eggs for retail sale, and a manufacturing industry that provides cooked eggs. This technology can be used in the food service industry.

Claims

1. A cooked product made from whole avian eggs, containing no whey and having dissolved inulin having a weight-average molecular weight of 500 to 4000, said cooked product being scrambled eggs, omelets or rolled eggs, and containing 0.5 to 20 parts by mass of dissolved inulin per 100 parts by mass of whole avian eggs.

2. A cooked product as described in claim 1, in which the inulin is dissolved at a uniform concentration throughout the cooked product.

3. A method for producing a cooked product from whole avian eggs, comprising the steps of: preparing an egg liquid from whole eggs from avian eggs; dissolving whey-free inulin having a weight-average molecular weight of 500 to 4000 in the egg liquid to prepare an inulin-containing egg liquid; and heating the inulin-containing egg liquid to coagulate at least a portion of it, wherein the cooked product is scrambled eggs, omelets or rolled eggs, and the amount of inulin dissolved is 0.5 to 20 parts by mass per 100 parts by mass of the scrambled eggs, omelets or rolled eggs.

Images