Processed food product for microwave cooking

Abstract

The purpose of the present invention is to provide a processed food product for microwave cooking that makes it possible to achieve an appearance and texture like that of grilled fish, obtained by heating and cooking a food product from the outside, even when a microwave cooking appliance is used to heat and cook the food product at a prescribed output and time setting. Provided is a processed food product formed by vacuum packing seafood and a liquid seasoning, wherein the oil and fat content of the entire liquid seasoning is 20% to 95% in terms of weight ratio and the water content of the entire liquid seasoning is more than 0% to 10% in terms of weight ratio.

Description

Microwave-safe processed foods

[0001] The present invention relates to a processed food for microwave cooking, which can be distributed and stored in a refrigerated or frozen state and is cooked using a microwave oven.

[0002] BACKGROUND ART There is an increasing demand for processed foods that can be easily cooked using a microwave cooker, or so-called microwave oven, for both commercial and home use.

[0003] Patent Document 1 describes a method for producing processed foods that includes a processing step of wetting the surface of the seafood material with a sugar-containing solution after seasoning it, a drying step, and a coating step of applying oil or fat to the surface of the seafood material, with the aim of obtaining a desirable browning similar to that of fish grilled over an open flame and a good flavor and texture resulting from the moderate evaporation of moisture, which concentrates the umami of the ingredients, when the seafood is cooked in a microwave oven from an unprocessed state.

[0004] In order to achieve the same purpose as in Patent Document 1, Patent Document 2 describes a process of making cuts in the skin and flesh of the fish to be processed, a process of applying a seasoning liquid to the surface of the fish, a method of grilling the fish by placing the fish on a special tray and heating it, a seasoning liquid containing wheat protein hydrolyzate, sake, corn syrup, salt, a sweetener, a thickener, an acidulant, and sake lees, and a special tray with ribs protruding from the bottom.

[0005] Patent Document 3 describes a food product for microwave cooking in which the moisture content of unheated food material is adjusted to 50-65%, and a paste-like browning agent made of edible oil, soy sauce, and grain flour is applied around the food, resulting in a browned appearance after microwave heating. According to the examples, the browning agent is made up of 50% to 70% by mass of oil, 27% to 46% by mass of soy sauce, and the remainder is grain flour, and the amount of moisture contained in the soy sauce is at least 20% by mass.

[0006] JP 2012-161286 A JP 2014-50348 A JP 2006-25773 A

[0007] Microwave cookers, such as microwave ovens, heat food by vibrating the water molecules contained in the food with microwave irradiation, making them easy to cook, but the temperature rises rapidly from the inside of the food, making it difficult to adjust the heating temperature uniformly throughout the food. As a result, excessive water evaporation can cause the food to become dry, or conversely, too much water can remain in the food.

[0008] The present invention aims to provide a processed food for microwave cooking that, when cooked using the above-mentioned microwave cooker with a specified output and time setting, can have the appearance and texture of grilled fish obtained by cooking the food from the outside.

[0009] According to the present invention, a processed food for microwave cooking is obtained, which is a vacuum-packed product of seafood and a seasoning liquid, characterized in that the amount of fat and oil in the entire seasoning liquid is 20% or more and 95% or less by weight, and the amount of water in the entire seasoning liquid is more than 0% and 10% or less by weight.

[0010] According to the present invention, the processed food for microwave cooking is obtained, characterized in that the amount of seasoning liquid added to the seafood is 3% or more and 20% or less by weight.

[0011] The processed food for microwave cooking of the present invention contains 20% to 95% by weight of oil or fat, preferably vegetable oil or fat, in the seasoning liquid, which allows the seafood to be cooked to be kept uniformly at a high temperature, giving it the appearance of grilled fish.

[0012] By using powdered soy sauce for the seasoning liquid, for example, and using ingredients other than fats and oils with extremely low moisture content, and by controlling the moisture content of the seasoning liquid to 10% or less by weight, it is possible to obtain the appearance, texture, and flavor of grilled fish without using sugar coating or ingredients that cause browning such as grain flour.

[0013] Furthermore, by adding a seasoning liquid amount of 3% to 20% by weight of the seafood to be cooked and vacuum-packing it, the amount of oil and fat contained in the seafood after cooking can be appropriately adjusted, and the texture and flavor of grilled fish can be obtained.

[0014] 1 is a graph showing the results of fracture analysis of a giant buffalo dory, a silver salmon, a redfish, and a whitefish.

[0015] The present invention is a processed food that can be stored in a refrigerator or freezer, and is prepared by adding a predetermined amount of raw seafood and a seasoning liquid that is rich in oil and fat and has a low water content, and then vacuum-packing the food.

[0016] The seafood used in the present invention is raw seafood that has not been heat-processed, and fillets of fish with lenticels are particularly suitable for processing. Furthermore, particularly preferred fish species include ocean perch (red fish (Alaskan ocean perch), white fish (northern ocean perch), red snapper, etc.), sea bream (big-eyed dory, spotted sea bream, etc.), mackerel (chub mackerel, yellowtail, etc.), salmon (coho salmon, white salmon (autumn salmon), etc.), silver cod, Pacific cod, and yellowtail, but other fish species may also be used. Furthermore, fish with firm flesh, or so-called muscular fish, are more preferred. Furthermore, squid, octopus, shrimp, shellfish, etc. may also be used.

[0017] The present invention is characterized by having an oil content of 20% to 95% by weight in the entire seasoning liquid, and a water content of more than 0% to 10% by weight. By increasing the amount of oil, the temperature of the food can be kept high when heated in a microwave oven, resulting in an appearance such as browning on the skin like that of grilled fish.In addition, by reducing the amount of water contained in the seasoning liquid significantly compared to conventional products, it is thought that the seafood is steamed mainly using the water contained in the seafood, resulting in a texture similar to that of grilled fish, without being dry or sticky.

[0018] Microwave heating utilizes the dielectric loss of water by irradiating it with 2.4 GHz electromagnetic waves, vibrating the water molecules contained in food. As is well known, water boils at 100°C under 1000 hectopascals of atmospheric pressure. However, the crystalline water contained in the crystal lattice of inorganic compounds such as calcium sulfate does not liberate even at temperatures above 100°C due to interactions with the inorganic compounds. Similarly, the polar groups of edible oils and water do not liberate even at temperatures above 100°C due to interactions such as hydrogen bonding, and the temperature rises to a point where seafood browns. In other words, adding a certain amount of oil or fat to a liquid seasoning is thought to produce a browned texture and flavor in seafood. However, various experiments have shown that seafood contains a certain amount of moisture, and this amount is sufficient to create a grilled fish-like texture when vacuum-packed seafood is microwaved. Adding more moisture than necessary from liquid seasonings, etc., can result in a watery texture, such as dryness or stickiness.

[0019] Based on the above considerations, the amount of fats and oils in the entire seasoning liquid depends on the type of seafood used, but when emphasis is placed on flavor and grilled fish texture, it is more preferably 40% to 80% by weight. The fats and oils may be any commonly available fats and oils, but vegetable fats are preferred, such as salad oil, olive oil, corn oil, safflower oil, sesame oil, soybean oil, sunflower oil, cottonseed oil, grapeseed oil, and rice (bran) oil. These fats and oils may be used alone or in combination. For flavoring purposes, flavored edible oils or animal fats and oils such as butter and margarine may be added in amounts of less than 1% by weight of the entire seasoning liquid, but these are not included in the fats and oils.

[0020] The seasoning liquid may contain powdered soy sauce, sugar, salt, various flavorings, spices, amino acids, colorings, emulsifiers, etc. For the reasons described below, it is preferable to select these additives with low water content.

[0021] The present invention is characterized by increasing the amount of oil and fat compared to conventional products, controlling the water content to 10% or less by weight, preferably 5% or less, and adding a seasoning liquid in an amount of 3% to 20% by weight based on the weight of the seafood to be cooked, followed by vacuum packing. As mentioned above, the inventors speculated that the amount of oil and water are important for achieving a grilled fish-like appearance and texture. Based on this, and through repeated experiments, they discovered that not only the blend of seasoning liquid but also the amount of seasoning liquid added relative to the weight of the target seafood, i.e., adjusting the amount of oil and water added relative to the weight of the target seafood, significantly contributes to achieving a grilled fish-like appearance and texture during microwave cooking. Note that the amount of seasoning liquid added depends on the type of seafood used, but when emphasis is placed on flavor and grilled fish texture, a weight ratio of 5% to 15% is more preferable.

[0022] Furthermore, the present invention can further enhance the above-mentioned effects by mixing or soaking seafood in a seasoning liquid of a predetermined composition, and then vacuum-packing the seafood, thereby allowing the seasoning liquid to penetrate deep into the seafood.

[0023] As a result of various experiments, in order for the seasoning liquid to properly penetrate seafood, the viscosity coefficient of the seasoning liquid at 20°C is preferably 20 mPa·s or more and 1000 mPa·s or less, and more preferably 30 mPa·s or more and 200 mPa·s or less.

[0024] A low surface tension of the seasoning liquid also contributes to the appropriate penetration of the seasoning liquid into seafood. Among the components constituting the seasoning liquid of the present invention, water has the highest surface tension at 20°C, at approximately 73 mN / m, while all of the oil and fat components have a surface tension of 30 to 35 mN / m, which is lower than that of water. In the present invention, adjusting the water content of the seasoning liquid to 10% or less by weight is thought to contribute to improving the penetration of the seasoning liquid into seafood. It is also thought that the adduct of amino acid and salt added as a seasoning functions as an emulsifier, reducing the surface tension and contributing to improving penetration. As a result of various experiments, it is preferable that the surface tension of the seasoning liquid is greater than 0 mN / m and less than 50 mN / m.

[0025] The packaging container used for vacuum packing can be any that is heat-resistant and pressure-resistant and made of a common material that is supplied and sold for packaging and vacuum packing food, etc., and the vacuum device can be any device that is supplied and sold for processing food, etc. It is more preferable to use a vacuum packing container that is equipped with a steam release mechanism or a pressure reduction mechanism.

[0026] The microwave power and heating time need to be adjusted depending on the amount of seafood and seasoning, but for 100g of seafood, it is preferable to use a power of 500W and a heating time of approximately 4 to 5 minutes.

[0027] The present invention will be described in more detail below using examples.

[0028] Example 1: 100 g of fillets of white fish (Northern Pacific cod) with skin and 10 g of seasoning liquids with different fat and oil contents were vacuum-packed. Each was heated in a microwave oven (500 W) for 5 minutes, removed from the pack, and compared for appearance and texture. The results are shown in Table 1. The seasoning liquid used consisted of salt, seasoning (amino acids), emulsifier, coloring, powdered soy sauce, and spices, and had a moisture content of 5% by weight.

[0029] The appearance was evaluated by measuring the black discoloration (scorched areas) in the entire skin using a mobile spectrophotometer (CM-700d) manufactured by Konica Minolta Japan, Inc., and the color difference ΔE* was used as the criterion for evaluation. Specifically, the microwave-cooked product and the product cooked on a grill for 12 minutes (hereinafter referred to as "grilled product") were each measured twice, and the average color difference ΔE* was calculated using the L*a*b* color system. Based on the relationship between color difference ΔE* and color tolerance compiled by the Japan Color Research Institute, a color difference ΔE*ab of 1.6 to 3.1 was rated as A (when comparing adjacent colors, almost no color difference is perceived, the colors are the same), 3.2 to 6.5 as B (the impression is that the colors are almost the same), and 6.6 or more (the color is perceived as different), with A being the same appearance as grilled fish (◎), B being nearly the same appearance as grilled fish (◯), and C being a different appearance from grilled fish (×). Furthermore, five tasters compared the texture and flavor with 100 g of white fish with skin that had been grilled for 12 minutes without being immersed in the seasoning liquid, and evaluated whether the texture and flavor were the same (◎), almost the same (◯), or significantly different (×). The opinions of the majority are shown in Table 1.

[0030]

[0031] As shown in Table 1, when the fat content was less than 20%, the majority of respondents evaluated that the skin was not browned properly, the texture was sticky, there was a lingering fishy smell, and it was different from grilled fish. Furthermore, when the fat content was more than 95%, the majority of respondents evaluated that the skin was browned too much, the texture was dry, and the flavor had a burnt smell. When the fat content was 40% or more and 80% or less, the overall evaluations of appearance, texture, and flavor were all good. When the fat content was 40% or more and 80% or less, the viscosity coefficient of the seasoning liquid at 20°C was measured using an Anton Paar rheometer (MCR302) and was found to be 30 mPa·s or more and 200 mPa·s or less. In addition, when the test was compared with grilled products using redfish, giant bream, chub mackerel, silver salmon, silver cod, Pacific rockfish, yellowtail, and neon flying squid, similar evaluation results were obtained.

[0032] Example 2: 100 g of fillets of white fish (Nippon nigra) with the skin on were vacuum-packed with different amounts of seasoning liquid, each containing 50% fat and 5% water by weight. Each was heated in a microwave oven (500 W) for 5 minutes, removed from the pack, and compared for appearance and texture. The results are shown in Table 2. The seasoning liquid used consisted of salt, seasoning (amino acids), emulsifier, coloring, powdered soy sauce, and spices.

[0033] The appearance was judged by determining the blackened areas (burnt areas) throughout the skin using the method described in Example 1. Five tasters also compared the texture and flavor with 100 g of white fish with skin that had been grilled for 12 minutes without immersing in the seasoning liquid, and evaluated the results as equivalent (◎), almost equivalent (◯), or significantly different (×). The majority opinions are shown in Table 2.

[0034]

[0035] As shown in Table 2, when the amount of seasoning liquid added was less than 3%, the majority of respondents evaluated that the food was overly browned, the texture was dry, and the flavor had a burnt smell. Furthermore, when the amount of seasoning liquid added was more than 20%, the majority of respondents evaluated that the food was not like grilled fish, with a light browning, a sticky texture, and a lingering fishy smell. When the amount of seasoning liquid added was between 5% and 15%, the overall evaluations of appearance, texture, and flavor were all good. When redfish, John Dory, Chub Mackerel, Coho Salmon, Silver Cod, Pacific Ocean Perch (Single-spotted Rockfish), Yellowtail, and Neon Flying Squid were compared with grilled products, similar evaluation results were obtained.

[0036] Example 3: 100 g of fillets of white fish (Northern Pacific cod) with skin and 10 g of seasoning liquid with 50% oil and varying water contents were vacuum-packed. Each was heated in a microwave oven (500 W) for 5 minutes, removed from the pack, and compared for appearance and texture. The results are shown in Table 3. The seasoning liquid used consisted of salt, seasoning (amino acids), emulsifier, coloring, powdered soy sauce, and spices.

[0037] The appearance was judged by determining the blackened areas (burnt areas) throughout the skin using the method described in Example 1. Five tasters also compared the texture and flavor with 100 g of white fish with skin that had been grilled for 12 minutes without immersing in the seasoning liquid, and rated the results as equivalent (◎), almost equivalent (◯), or significantly different (×). The majority opinions are shown in Table 3.

[0038]

[0039] As shown in Table 3, when the water content of the seasoning liquid was more than 10%, the browning was light, the texture was sticky and watery, and there was a lingering fishy smell, and the majority of the respondents rated it as different from grilled fish. When the amount of seasoning liquid added was 10% or less and 0.1% or more, the overall evaluations of appearance, texture, and flavor were all good. When redfish, John Dory, Chub mackerel, silver salmon, silver cod, Pacific rockfish (single-spotted rockfish), yellowtail, and neon flying squid were compared with grilled products, similar evaluation results were obtained.

[0040] Example 4: 100 g each of fillets of John Dory, Coho Salmon, redfish (Alaskan Pacific ocean perch), and whitefish (Northern Pacific ocean perch), all with the skin on, and 10 g of the same seasoning liquid used in the other examples, with an oil content of 50% and a water content of 5% by weight, were vacuum-packed. Each was heated in a microwave oven (500 W) for 5 minutes, removed from the pack, and then analyzed for breaking strength at two locations on each piece other than the skin using a Creep Meter RE2 33005S (texture evaluation device) manufactured by Yamaden Co., Ltd. For comparison, 100 g each of fillets of John Dory, Coho Salmon, redfish (Alaskan Pacific ocean perch), and whitefish (Northern Pacific ocean perch), all with the skin on, were prepared (without immersion in the seasoning liquid, etc.), and after grilling, were analyzed for breaking strength in the same manner as above.

[0041] The results are shown in Figures 1 to 4. In each figure, the vertical axis of the graph represents the load (gf), the horizontal axis represents the strain rate (%), the solid line represents the example of the present invention, and the dashed line represents the comparative example.

[0042] For both fillets, the microwave-cooked and grilled products of the present invention showed almost identical load (gf) and strain rate (%) curves, although the strain rate differed depending on the part, and it was considered that there was no significant difference in texture.

[0043] Although the present invention has been described above using examples, the present invention is not limited to these examples.

[0044] According to the present invention, raw seafood can be easily cooked using a microwave oven, and can be easily obtained without being sticky or dry, with an appearance, texture, and flavor similar to that of grilled fish, etc. Therefore, this invention is expected to promote consumption of seafood, which tends to be avoided due to the complexity of cooking, and to have synergistic applications not only in the food processing field but also in related industrial fields such as the fishing industry.

Claims

1. A processed food for microwave cooking, comprising seafood and a seasoning liquid vacuum-packed, the seasoning liquid having an overall fat content of 20% or more and 95% or less by weight, and an overall moisture content of more than 0% and 10% or less by weight.

2. A processed food for microwave cooking according to claim 1, characterized in that the amount of said seasoning liquid added to said seafood is 3% or more and 20% or less by weight.

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