High-conformality, high-moisture and high-nutrition thick-wall stuffed bean curd and preparation method thereof

Abstract

The invention discloses thick-wall stuffed bean curd with high shape retention, high moisture and high nutrition and a preparation method of the thick-wall stuffed bean curd, and belongs to the technical field of food processing. The nut protein is added into the bean curd skin, and meanwhile, the preparation process is controlled to realize the effects of high moisture content, high nutritional value, high shape retention and multiple stuffing choices of the stuffed bean curd. Specifically, the stuffed bean curd prepared by the preparation method does not need to be shaped in a deep-frying or water boiling manner, and can be shaped only by a pressing process; various types of fillings (meat products, aquatic products, vegetable fillings and the like) can be added, and a shaping agent does not need to be added into the fillings; and meanwhile, the pot can be suitable for various cooking modes such as frying, frying and boiling. In addition, the stuffed bean curd is low in fat, high in protein, high in elasticity and diversified in flavor.

Description

Technical Field

[0001] The invention relates to thick-wall stuffed tofu with high shape retention, high moisture content and high nutrition and a preparation method thereof, and belongs to the technical field of food processing. Background Art

[0002] Stuffed tofu is a tofu product with a filling inside. The filling includes fish paste, shrimp, shrimp meat, pork, shrimp roe and other core materials, and the outer skin is tofu or bean curd skin products. The production method of stuffed tofu is more complicated than that of ordinary tofu. At present, there are no stuffed tofu products on the market. The main reason is that tofu products are difficult to shape, easy to loosen, and difficult to successfully stuff. Stuffed fish tofu products are mostly shaped by frying, and the product has a high oil content.

[0003] At present, stuffed bean products are mainly concentrated in fish tofu products and tofu foam products, rather than tofu made from bean products, as follows:

[0004] Oden products are tofu puff products that are fried and shaped. Similar to the "lucky bag" structure, oden has fillings such as fish balls and meatballs added to it, and is tied with a tie design. The product is large in size, and there is a large gap between the contents and the outer skin of the tofu puff. The applicable cooking methods are limited, and it is mainly suitable for boiled foods.

[0005] CN112568391A discloses a formula for a delicious lucky bag and a processing method thereof, which uses deep-fried Japanese tofu to set the shape, then hollows out the Japanese tofu and stuffs it with fillings. The production method is similar to the lucky bag structure in the aforementioned oden, which requires deep-frying to set the shape, and the cooking method of the obtained product is limited, and it is mainly suitable for boiled foods.

[0006] CN114052216A discloses a method for preparing stuffed fish tofu that can be stored at room temperature, which uses frying to shape the fish skin and prevent the stuffing from leaking out.

[0007] CN105285556 discloses a method for frying tofu, which involves dividing the tofu into two pieces, adding stuffing in between, and frying the pieces to fix the pieces. However, the stuffing in the tofu dish prepared by this method is easy to fall out, and the product is only suitable for immediate consumption and belongs to a ready-to-eat dish. It cannot be sold as a pre-prepared dish or a finished tofu product. In addition, the processing method is only frying, and the obtained tofu product cannot be cooked a second time, which is inconvenient to store and transport.

[0008] CN114041565A discloses a processing method for stuffed tofu, which mainly focuses on solving the technical problems in the prior art that tofu has a single nutritional component and poor taste and layering. It mainly coats the surface of meatballs with tomato sauce and pig skin slurry, and adds Chinese medicinal materials to the stuffing to provide health-care ingredients, namely: innovations are made in the stuffing formula and the tools for pressing tofu; however, it does not mention whether it can be used for special processing methods such as frying, and how the shape-retaining effect is under different processing environments.

[0009] In summary, in order to better meet the needs of the market and consumers, there is an urgent need for a thick-walled stuffed tofu with high shape retention, high moisture content and high nutrition, which does not require frying or boiling to set the shape, has a good molding effect, is not dry and woody in taste, is not prone to loosening or breaking after long cooking, and is suitable for a variety of cooking methods; it can also enrich the flavor and taste and increase the content of nutrients such as protein and amino acids while retaining the original moisture and protein content of the tofu. Summary of the invention

[0010] [Technical issues]

[0011] Conventional stuffed tofu has the disadvantages of single stuffing, single flavor and functional ingredients, insufficient elasticity, poor shape retention, and difficulty in adapting to special processing methods such as frying.

[0012] [Technical solution]

[0013] In order to solve the above problems, the present invention adds nut protein to the tofu skin, and controls the preparation process to achieve the effects of high moisture content, high nutritional value, high shape retention and multiple fillings selection of stuffed tofu. Specifically, the stuffed tofu prepared by the present invention does not need to be shaped by frying or boiling, but only needs to be shaped by a pressing process; various types of fillings (meat products, aquatic products, vegetable fillings, etc.) can also be added without adding a setting agent to the fillings; and it can be suitable for various cooking methods such as frying, deep-frying, and boiling. In addition, the stuffed tofu of the present invention is low in fat, high in protein, high in elasticity and has a variety of flavors.

[0014] The first object of the present invention is to provide a method for preparing thick-walled stuffed tofu with high shape retention, high moisture content and high nutrition, comprising the following steps:

[0015] (1) Soaking, grinding, filtering, boiling, adding brine, and allowing to settle to form tofu pudding;

[0016] (2) adding nut protein, enzyme preparation, salt, and binder to the tofu pudding, mixing them evenly, and obtaining a cortex mixture; wherein the mass ratio of the tofu pudding, nut protein, enzyme preparation, salt, and binder is (38-58):(5-10):(0.5-2):(0.1-1):(0.1-0.5);

[0017] (3) pouring half the volume of the skin layer mixture into the lower skin layer mold, pressing at 3-5 MPa and 30-50° C. to form the lower skin layer of stuffed tofu;

[0018] (4) Add stuffing to the lower skin layer of stuffed tofu and cover it with an upper skin layer mold. Pour the other half volume of the skin layer mixture into the upper skin layer mold and press at 3-5 MPa and 30-50° C. to form an upper skin layer of stuffed tofu, thereby obtaining thick-walled stuffed tofu.

[0019] In one embodiment of the present invention, the soybean in step (1) is soybean.

[0020] In one embodiment of the present invention, the soaking in step (1) is to soak soybeans and water in a mass ratio of 1:10-15 in water at 20-25° C. for 10-12 hours to obtain wet soybeans.

[0021] In one embodiment of the present invention, the grinding in step (1) is to mix wet soybeans with water in a mass ratio of 1:3 to 8, and grind them for 2 to 10 minutes at a colloid mill speed of 3000 to 5000 r / min to obtain a slurry.

[0022] In one embodiment of the present invention, the filtration in step (1) is to repeatedly filter the slurry 2 to 3 times using a sieve with a pore size of 60 to 80 mesh to obtain a filtered slurry.

[0023] In one embodiment of the present invention, the boiling in step (1) is to boil the filtered slurry and then continue to boil for 2 to 3 minutes to obtain a boiled slurry; wherein, the boiling process requires continuous stirring, and the stirring speed is 20 to 50 rpm.

[0024] In one embodiment of the present invention, in step (1), the brine is firstly cooled to 80-90°C after the cooking, and then a brine solution is added to the cooked slurry to precipitate the protein, thereby obtaining a brine-treated slurry; wherein the brine is one or two of magnesium chloride and calcium sulfate; the mass ratio of magnesium chloride to calcium sulfate is 1:1; the mass concentration of the brine solution is 18-22%; and the mass ratio of the brine solution to the cooked slurry is 0.03-0.05:1.

[0025] In one embodiment of the present invention, the static precipitation in step (1) is to statically precipitate the slurry after the brine is precipitated at 75-85° C. for 3-10 minutes until it is completely precipitated, and then remove the supernatant.

[0026] In one embodiment of the present invention, the solid content of the tofu pudding in step (1) is 30-80%.

[0027] In one embodiment of the present invention, the nut protein in step (2) is one or more of peanut protein, pistachio protein, hazelnut protein, walnut protein, and moringa seed protein.

[0028] In one embodiment of the present invention, the enzyme preparation in step (2) is transglutaminase (TGase) with an enzyme activity of 300 U / g.

[0029] In one embodiment of the present invention, the binder in step (2) is one or more of gellan gum, carrageenan, tapioca starch, and xanthan gum.

[0030] In one embodiment of the present invention, the temperature of the tofu pudding needs to be lowered to 40-60° C. before the nut protein, enzyme preparation, salt and binder are added in step (2).

[0031] In one embodiment of the present invention, the shape of the upper skin layer mold and the lower skin layer mold in steps (3) and (4) is one of rhombus, circle, square and hexagon.

[0032] In one embodiment of the present invention, the amount of the skin layer mixture in the upper skin layer mold and the lower skin layer mold in steps (3) and (4) is 0.5-1.0 mL / cm 3 .

[0033] In one embodiment of the present invention, the upper skin layer mold and the lower skin layer mold in steps (3) and (4) can be a single thick-walled stuffed tofu mold, or a mold composed of several thick-walled stuffed tofu, which are then cut into individual thick-walled stuffed tofu.

[0034] In one embodiment of the present invention, the thickness of the upper skin layer and the lower skin layer of the stuffed tofu in steps (3) and (4) are the same, both of which are 0.5 to 1.5 cm.

[0035] In one embodiment of the present invention, the pressing time in steps (3) and (4) is 10 to 20 minutes.

[0036] In one embodiment of the present invention, the mass ratio of the total crust mixture to the filling in steps (3) and (4) is (6-8):(2-4).

[0037] In one embodiment of the present invention, the filling in step (4) includes one or more of shrimp, shrimp meat, crab roe, fish meat, shrimp roe, fish roe, minced meat, shredded radish, and mashed potatoes.

[0038] In one embodiment of the present invention, in step (4), the filling is shaped and frozen by pre-freezing, thereby eliminating the step of wrapping the filling with a setting agent and reducing the use of additives.

[0039] In one embodiment of the present invention, in step (4), the filling is placed at the center of the lower skin layer of the stuffed tofu.

[0040] In one embodiment of the present invention, when the filling in step (4) is spherical, the diameter is 0.5 to 1.5 cm.

[0041] In one embodiment of the present invention, the stuffed tofu in step (4) can be cut, packaged, sterilized, and refrigerated to obtain a finished stuffed tofu product; the sterilization is heating at 80-95° C. for 5-45 minutes; the refrigeration is refrigerated storage at 0-4° C.

[0042] The second objective of the present invention is to prepare thick-walled stuffed tofu with high shape retention, high moisture content and high nutrition by the method of the present invention.

[0043] In one embodiment of the present invention, the shape of the thick-walled stuffed tofu is one of rhombus, circle, square and hexagon; when the shape is square, the size is 3-5 cm×3-5 cm.

[0044] In one embodiment of the present invention, high moisture content means that the moisture content of the upper and lower skin layers of the stuffed tofu is above 75%; thick wall means that the thickness of the upper and lower skin layers of the stuffed tofu is 0.5-1.5 cm, so as to maintain its elastic and smooth taste; high shape retention means that the shape of the stuffed tofu is well maintained after frying, deep-frying and boiling; high nutrition means that the stuffed tofu contains not only the nutrients of the tofu itself, but also the nutrients of nut protein and the filling.

[0045] In one embodiment of the present invention, the thick-walled stuffed tofu can be eaten immediately.

[0046] The third object of the present invention is the application of the thick-walled stuffed tofu of the present invention in the food field.

[0047] In one embodiment of the present invention, the food includes a pre-prepared dish or is used as a raw material or side dish for other foods.

[0048] The fourth object of the present invention is to provide an instant tofu, which adopts the thick-walled stuffed tofu of the present invention.

[0049] A fifth object of the present invention is to provide a method for improving the shape retention, moisture content and nutrient content of stuffed tofu, comprising the following steps:

[0050] (1) Soaking, grinding, filtering, boiling, adding brine, standing and settling the soybeans, and removing the supernatant to form tofu pudding;

[0051] (2) adding nut protein, enzyme preparation, salt, and binder to the tofu pudding, mixing them evenly, and obtaining a cortex mixture; wherein the mass ratio of the tofu pudding, nut protein, enzyme preparation, salt, and binder is (38-58):(5-10):(0.5-2):(0.1-1):(0.1-0.5);

[0052] (3) pouring half the volume of the skin layer mixture into the lower skin layer mold, pressing at 3-6 MPa and 30-50° C. to form the lower skin layer of stuffed tofu;

[0053] (4) Add stuffing to the lower skin layer of stuffed tofu and cover it with an upper skin layer mold. Pour the other half volume of the skin layer mixture into the upper skin layer mold and press at 3-6 MPa and 30-50° C. to form an upper skin layer of stuffed tofu, thereby obtaining stuffed tofu.

[0054] [Beneficial Effects]

[0055] (1) The thick-walled stuffed tofu prepared by the present invention has a high moisture content (more than 70%), which ensures its high elasticity. The bean curd skin contains various nut proteins and a variety of fillings, which are rich in nutrition and taste. It does not need to be fried or boiled to set, and is suitable for a variety of cooking methods.

[0056] (2) The preparation method of the present invention helps to maintain the elastic and smooth taste and cooking stability of tofu products.

[0057] (3) The thick-walled stuffed tofu prepared by the present invention has different inner and outer layers and tastes, and is not dry or woody, thereby providing an efficient and economical method for preparing a stuffed tofu product with high elasticity and high protein.

[0058] (4) The present invention adds nut protein to the upper and lower skin layers of the thick-walled stuffed tofu, thereby increasing the nutritional content and molding effect of the thick-walled stuffed tofu.

[0059] (5) The present invention controls the moisture content, thereby ensuring the elastic texture of the stuffed tofu and ensuring the molding effect.

[0060] (6) The thick-walled stuffed tofu of the present invention is added with various types of stuffings (meat products, aquatic products, vegetables, etc.), and the stuffings do not need to be wrapped with a setting agent, and the stuffed tofu can be pressed and formed.

[0061] (7) The thick-walled stuffed tofu of the present invention is low in fat, high in protein, highly elastic and has a variety of flavors, and can be suitable for a variety of cooking methods such as frying, stir-frying, boiling and deep-frying.

[0062] (8) The protein content of the upper and lower skin layers and the fillings of the thick-walled stuffed tofu of the present invention are high; specifically, the fillings themselves are high-protein products such as shrimp meat, fish meat, pork, crab roe, etc., and the upper and lower skin layers are also high-protein products, which contain not only soybean protein, but also additional nut proteins such as peanut protein, pistachio protein, walnut protein, and moringa seed protein, which supplement the low content of lysine and methionine in soy products, and are beneficial to the human body to supplement rich amino acids.

[0063] (9) The thick-walled stuffed tofu of the present invention is similar in structure to the "lucky bag" in oden, but the finished product form is different; the tofu and the stuffing in the thick-walled stuffed tofu of the present invention are integrally formed and tightly wrapped, and can be directly cooked after sterilization and refrigeration, and will not become loose after long cooking, and has a good shaping effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 This is a finished picture of the thick-walled stuffed tofu prepared in Examples 1 to 3.

[0065] Figure 2 The sensory evaluation diagram of the finished thick-walled stuffed tofu in Examples 1 to 4 and Comparative Examples 1 to 4 is shown.

[0066] Figure 3 This is a picture of the raw thick-walled stuffed tofu in Example 2 and its products after being boiled, fried and deep-fried.

[0067] Figure 4 This is a cross-sectional view of the thick-walled stuffed tofu after being boiled and fried in Example 2.

[0068] Figure 5 This is a picture of the product of the thick-walled stuffed tofu after being boiled in comparative example 2. DETAILED DESCRIPTION

[0069] The preferred embodiments of the present invention are described below. It should be understood that the embodiments are for better explaining the present invention and are not used to limit the present invention.

[0070] Test method:

[0071] 1. Sensory evaluation:

[0072] The sensory evaluation team consists of 10 people with experience in sensory evaluation.

[0073] Before conducting a sensory evaluation, evaluators need to follow certain regulations and preparations: no alcohol, smoking, or spicy or irritating food should be consumed two hours before the evaluation; no communication or discussion of any kind should be conducted during the evaluation; and there should be at least 10 minutes between the evaluations of each sample to avoid any impact of taste residue on subsequent evaluations.

[0074] The sensory evaluation criteria are shown in Table 1, and the maximum score for each item is 15 points.

[0075] Table 1 Sensory evaluation score table

[0076]

[0077] 2. Test of moisture content of the upper and lower layers of stuffed tofu:

[0078] Refer to GB5009.3-2016 Determination of moisture in food Direct drying method;

[0079] Specific:

[0080] Randomly select 5 portions of stuffed tofu, cut about 1-2g of the upper and lower layers of tofu as samples, put them in a crucible, weigh them using a balance and record them; put the samples in an oven, set the temperature to 105℃, and after the samples are dried in the oven for 4h, take them out and place them in a dryer to cool for 0.5h, and weigh them for the second time using a balance.

[0081] According to the mass difference of the sample before and after drying, the water content in the sample is calculated using formula (1):

[0082]

[0083] Where: x is the water content, in mass percentage, %;

[0084] m1 is the mass of the sample before drying, in g;

[0085] m2 is the mass of the sample after drying, in g.

[0086] To ensure the accuracy and reliability of the experimental results, repeat the above steps three times and take the average of the three results as the moisture content of the sample.

[0087] The raw materials used in the embodiments and comparative examples are:

[0088] 1.Soybeans: dried soybeans.

[0089] 2. Glutamine transaminase: enzyme activity is 300U / g.

[0090] 3. The filling is shaped and frozen by pre-freezing.

[0091] 4. Starch: corn starch, commercially available.

[0092] 5. The preparation method of nut protein is as follows:

[0093] Peanuts, pistachios, and hazelnuts (shellless and skinless) were ground into 20 mesh, mixed with water at a ratio of 1:10 (g / mL), adjusted to pH 9 with 3 mol / L NaOH solution, magnetically stirred at 25°C for 1 h, and then centrifuged at 4°C (5000g, 15min), the supernatant was collected, and the precipitate was repeatedly adjusted to pH 9 with 3 mol / L NaOH solution and extracted twice; the supernatants were combined, filtered, and the pH value was adjusted to 4.5 with 3 mol / L HCl solution, allowed to stand at room temperature for 20 min, and centrifuged under the same conditions (5000g, 15 min), and the precipitate was washed with deionized water until neutral to obtain nut protein.

[0094] 6. The preparation method of tofu pudding is as follows:

[0095] (1) Soaking:

[0096] Soak dry soybeans and water in 25°C water at a mass ratio of 1:10 for 12 hours to obtain wet soybeans;

[0097] (2) Refining:

[0098] The wet soybeans were mixed with water in a mass ratio of 1:3.5, and ground in a colloid mill at a speed of 5000 r / min for 5 min to obtain a slurry;

[0099] (3) Filtering:

[0100] The slurry was filtered twice using a 60-mesh sieve to obtain a filtered slurry;

[0101] (4) Boil:

[0102] The filtered slurry was boiled and then continued to be boiled for 3 minutes. The boiling process required constant stirring at a stirring speed of 30 rpm to obtain the boiled slurry;

[0103] (5) Add gravy:

[0104] First, the boiled slurry is cooled to 85°C, and then a mixed aqueous solution of magnesium chloride and calcium sulfate is added to the boiled slurry to precipitate protein, thereby obtaining a brined slurry; wherein the mass ratio of magnesium chloride to calcium sulfate is 1:1; the mass concentration of the mixed aqueous solution of magnesium chloride and calcium sulfate is 20%, and the mass ratio of the mixed aqueous solution of magnesium chloride and calcium sulfate to the boiled slurry is 0.04:1;

[0105] (6) Settling

[0106] The slurry after brine was placed at 80°C for 8 minutes to settle until it was completely precipitated; the supernatant was removed to obtain tofu pudding (solid content of 60%).

[0107] 7. The preparation method of vegetable balls is as follows:

[0108] Shredded radish and carrot are obtained by adding 3% salt, pickling for 10 minutes, and then squeezing and dehydrating to obtain vegetables;

[0109] Vegetable balls prepared by mixing vegetables, corn starch, spices (the mass ratio of pepper powder, star anise powder and chili powder is 1:1:1) and salt in a mass ratio of 86:10:1:3 were frozen at -18°C for later use.

[0110] 8. The cutting mentioned in the embodiment refers to cutting into thick-walled stuffed tofu, the sterilization refers to heating at 80°C for 30 min, and the refrigeration refers to storage at 4°C; the % mentioned without specific meaning refers to mass percentage; the solution mentioned without specific solvent refers to water as the solvent.

[0111] Example 1 (skin-filling ratio of 7:3, peanut protein, pressure 3 MPa, shrimp)

[0112] A method for preparing thick-walled stuffed tofu with high shape retention, high moisture content and high nutrition comprises the following steps:

[0113] (1) lowering the temperature of the tofu pudding to 50° C., adding peanut protein, glutamine transaminase, salt, and xanthan gum to the tofu pudding, and mixing them evenly to obtain a cortex mixture; wherein the mass ratio of the tofu pudding, peanut protein, glutamine transaminase, salt, and xanthan gum is 58:10:0.5:1:0.5;

[0114] (2) Pour half of the skin layer mixture into a lower skin layer mold (round, 5 cm in diameter), and press at 3 MPa and 40° C. for 10 min to form a lower skin layer of stuffed tofu; wherein the amount of the skin layer mixture in the lower skin layer mold is 15 mL, and the thickness of the lower skin layer of stuffed tofu is 0.7 cm;

[0115] (3) placing pre-frozen shrimp filling (spherical, 1 cm in diameter) at the center of the lower skin layer of stuffed tofu, and covering it with an upper skin layer mold (round, 5 cm in diameter), pouring the other half volume of the skin layer mixture into the upper skin layer mold, the amount of the skin layer mixture in the upper skin layer mold is 15 mL, and the thickness of the upper skin layer of the stuffed tofu is 0.7 cm; pressing at 3 MPa and 40° C. for 10 min to form the upper skin layer of the stuffed tofu; finally, cutting, packaging, sterilizing, and refrigerating to obtain the stuffed tofu;

[0116] Among them, the mass ratio of the cortex mixture to the shrimp filling is 7:3.

[0117] Comparative Example 1 (skin-filling ratio: 7:3, no peanut protein, pressure 3MPa, shrimp)

[0118] The addition of peanut protein in Example 1 was omitted, and the mass ratio of tofu pudding, glutamine transaminase, salt and xanthan gum was adjusted to 68:0.5:1:0.5; the rest was kept consistent with Example 1 to obtain stuffed tofu.

[0119] Comparative Example 2 (skin-filling ratio: 7:3, peanut protein, pressure 3MPa, shrimp, starch)

[0120] The glutamine aminotransferase and xanthan gum in Example 1 were adjusted to corn starch, that is, the mass ratio of tofu pudding, peanut protein, salt, and corn starch was 58:10:1:1; the rest was kept consistent with Example 1 to obtain stuffed tofu.

[0121] Example 2 (skin-filling ratio of 5:5, pistachio protein, pressure 3 MPa, crab roe)

[0122] A method for preparing thick-walled stuffed tofu with high shape retention, high moisture content and high nutrition comprises the following steps:

[0123] (1) lowering the temperature of the tofu pudding to 50° C., adding pistachio protein, glutamine transaminase, salt, and xanthan gum to the tofu pudding, and mixing them evenly to obtain a cortex mixture; wherein the mass ratio of the tofu pudding, pistachio protein, glutamine transaminase, salt, and xanthan gum is 38:10:0.5:1:0.5;

[0124] (2) Pour half the volume of the skin layer mixture into a lower skin layer mold (hexagonal, with a side length of 2.6 cm), and press at 3 MPa and 40° C. for 10 min to form a lower skin layer of stuffed tofu; wherein the amount of the skin layer mixture in the lower skin layer mold is 10 mL, and the thickness of the lower skin layer of the stuffed tofu is 0.5 cm;

[0125] (3) placing pre-frozen crab roe filling (spherical, with a diameter of 1.0 cm) at the center of the lower skin layer of stuffed tofu, and covering it with an upper skin layer mold (hexagonal, with a side length of 2.6 cm), pouring the other half volume of the skin layer mixture into the upper skin layer mold, the amount of the skin layer mixture in the upper skin layer mold is 10 mL, and the thickness of the upper skin layer of the stuffed tofu is 0.5 cm; pressing at 3 MPa and 40° C. for 10 min to form the upper skin layer of the stuffed tofu; and finally cutting, packaging, sterilizing, and refrigerating to obtain the stuffed tofu;

[0126] Among them, the mass ratio of the cortex mixture and the shrimp filling is 5:5.

[0127] Comparative Example 3 (skin-filling ratio: 5:5, pistachio protein, pressure 6 MPa, crab roe)

[0128] The pressing pressure in steps (2) and (3) of Example 2 was adjusted to 6 MPa, and the other conditions were kept the same as in Example 2 to obtain stuffed tofu.

[0129] Comparative Example 4 (skin-filling ratio of 5:5, pistachio protein, pressure 2MPa, crab roe)

[0130] The pressing pressure in steps (2) and (3) of Example 2 was adjusted to 2 MPa, and the other conditions were kept the same as in Example 2 to obtain stuffed tofu.

[0131] Example 3 (skin-filling ratio of 7:3, peanut protein, pressure 3 MPa, vegetable balls)

[0132] A method for preparing thick-walled stuffed tofu with high shape retention, high moisture content and high nutrition comprises the following steps:

[0133] (1) lowering the temperature of the tofu pudding to 50° C., adding peanut protein, transglutaminase, salt, and xanthan gum to the tofu pudding, and mixing them evenly to obtain a cortex mixture; wherein the mass ratio of the tofu pudding, peanut protein, transglutaminase, salt, and xanthan gum is 58:10:0.5:1:0.5;

[0134] (2) Pour half of the cortical mixture into the lower cortical mold (diamond-shaped, volume 16 cm 3 ), pressing at 3MPa and 40°C for 10min to form a lower skin layer of stuffed tofu; wherein the amount of the skin layer mixture in the lower skin layer mold is 12mL, and the thickness of the lower skin layer of stuffed tofu is 0.7cm;

[0135] (3) Place the pre-frozen vegetable ball filling (spherical, 0.6 cm in diameter) in the center of the lower skin layer of stuffed tofu, and cover it with the upper skin layer mold (diamond, 16 cm in volume). 3 ), pouring the other half volume of the skin layer mixture into the upper skin layer mold, the amount of the skin layer mixture in the upper skin layer mold is 12 mL, and the thickness of the upper skin layer of the stuffed tofu is 0.7 cm; pressing at 3 MPa and 40° C. for 10 min to form the upper skin layer of the stuffed tofu; finally, cutting, packaging, sterilizing, and refrigerating to obtain the stuffed tofu;

[0136] Among them, the mass ratio of the cortex mixture and the vegetable ball filling is 7:3.

[0137] Example 4 (skin-filling ratio of 5:5, peanut protein, pressure 3 MPa, vegetable balls)

[0138] The mass ratio of tofu pudding, peanut protein, glutamine transaminase, salt and xanthan gum in Example 3 was adjusted to 38:10:0.5:1:0.5; the mass ratio of the cortex mixture and the vegetable ball filling was 5:5, and the others were kept consistent with Example 3 to obtain stuffed tofu.

[0139] The stuffed tofu prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were subjected to performance tests, and the test results are as follows:

[0140] Table 2 Design of the embodiments and comparative examples

[0141] example Skin to filling ratio Add protein Pressure(Mpa) Filling type Enzyme preparation + adhesive Example 1 7:3 Peanut protein 3 Shrimp TG+Xanthan Gum Comparative Example 1 7:3 - 3 Shrimp TG+Xanthan Gum Comparative Example 2 7:3 Peanut protein 3 Shrimp Starch only Example 2 5:5 Pistachio Protein 3 Crab roe TG+Xanthan Gum Comparative Example 3 5:5 Pistachio Protein 6 Crab roe TG+Xanthan Gum Comparative Example 4 5:5 Pistachio Protein 2 Crab roe TG+Xanthan Gum Example 3 7:3 Peanut protein 3 Vegetable Balls TG+Xanthan Gum Example 4 5:5 Peanut protein 3 Vegetable Balls TG+Xanthan Gum

[0142] Table 3 Test results of embodiments and comparative examples

[0143] example Water content (%) Overall preference (points) Flavor evaluation score (points) Texture score (points) Example 1 77.11 13.6 13 12 Comparative Example 1 78.02 11 11 11 Comparative Example 2 78.81 10 12.5 8.8 Example 2 76.42 14 13.5 12.7 Comparative Example 3 70.39 11.8 12 10 Comparative Example 4 79.65 10 12.5 8.6 Example 3 77.29 12.8 11 10.8 Example 4 78.65 11 10.3 10

[0144] Figure 1 This is a finished picture of the thick-walled stuffed tofu prepared in Examples 1 to 3. Figure 2 The sensory evaluation diagrams of the finished thick-walled stuffed tofu in Examples 1 to 4 and Comparative Examples 1 to 4 are shown in Table 2. Table 2 shows the scheme designs of different Examples and Comparative Examples, and Table 3 shows the test results of the water content and overall liking of the stuffed tofu.

[0145] from Figure 1 , Figure 2 From Table 2 and Table 3, we can see that:

[0146] (1) The stuffed tofu prepared in Example 1 has a complete appearance and good shape, and its water content is 77.11%, which ensures the elastic taste and special flavor of the product. After being boiled, the aquatic product combined with the peanut aroma of the tofu skin tastes similar to the flavor combination of seafood and peanut butter in hot pot. The flavor evaluation in the sensory evaluation is 13 points, the texture score is 12 points, and the overall preference is 13.6 points. The addition of peanut protein enriches the flavor and health function of the product.

[0147] (2) The stuffed tofu prepared in Comparative Example 1 has a complete appearance and good shape, and its water content is 78.02%. The product has a good elastic taste, but the flavor is insufficient. After being boiled, the flavor score in the sensory evaluation is 11 points, which is lower than that in Example 1, the texture score is 11 points, and the overall preference is 11 points, which is lower than the overall score in Example 1.

[0148] (3) The stuffed tofu product prepared in Comparative Example 2 can be formed, but its shape retention is poor. After boiling, the sensory evaluation of flavor is 12.5 points, the texture score is 8.8 points, the overall preference is 10 points, and the overall elasticity and taste score of the product are lower than those of Example 1.

[0149] (4) The stuffed tofu prepared in Example 2 has a complete appearance and good shape, and its water content is 76.42%, which ensures the elastic taste and characteristic flavor of the product. After being boiled, the crab roe filling combined with the pistachio aroma of the tofu skin has a good taste, and its flavor evaluation score is 13.5 points, the texture score is 12.7 points, and the overall preference level is 14 points, which is higher than the overall score of Example 1.

[0150] (5) The stuffed tofu prepared in Comparative Example 3 had a complete appearance but poorly formed, and its water content was 70.39%. The sensory evaluation results showed that the outer skin of the product was too dry, resulting in a dry and woody taste, and the hardness was improved but the elasticity was poor. After being boiled, the product had a good flavor but a low texture score, with a flavor evaluation score of 12 points, a texture score of 10 points, and an overall preference of 11.8 points. The overall sensory evaluation was lower than that of Examples 1 and 2.

[0151] (6) The water content of the stuffed tofu prepared in Comparative Example 4 was 79.65%, and its texture was looser than that of Example 2, and its shape retention was not as good as that of Example 2. After being boiled, its flavor score was 12.5 points, the texture score was 8.6 points, and the overall preference was 10 points in the sensory evaluation, and the overall sensory evaluation score was lower than that of Example 2.

[0152] (7) The stuffed tofu prepared in Example 3 has a complete appearance and good shape, and its water content is 77.29%, which ensures the elastic taste and nutritional content of the product. After boiling, its flavor evaluation score is 11 points, the texture score is 10.8 points, and the overall preference is 12.8 points. The overall score of vegetable ball stuffing tofu is lower than that of aquatic product stuffing tofu.

[0153] (8) The stuffed tofu prepared in Example 4 has a complete appearance and good shape, and its water content is 78.65%, which ensures the elastic taste and nutritional content of the product. The elasticity is slightly poor because the skin is thin. After boiling, the flavor evaluation score in the sensory evaluation is 10.3 points, the texture score is 10 points, and the overall preference is 11 points, which is lower than that of Example 3.

[0154] After cooking, sensory evaluation tests revealed that:

[0155] (1) After being boiled, fried, and deep-fried, Example 1 retained its shape very well without cracking.

[0156] (2) Example 2 is boiled, fried and deep-fried ( Figure 3 ) after the product shape remains intact and the cut is smooth ( Figure 4 ) and the cut surface is complete without any cracks or leakage.

[0157] After frying, the sensory evaluation of Example 2 showed that the overall preference was 14.3 points, the texture score was 14 points, and the flavor evaluation score was 13.6 points. The sensory evaluation results showed that after frying, the product had good shape retention, better flavor, and improved elasticity.

[0158] After frying, the sensory evaluation of Example 2 showed that its overall preference was 14.1 points, the texture score was 13.6 points, and the flavor evaluation score was 14 points; after frying, the product had good shape retention and better elasticity, was crispy on the outside and tender on the inside, and the flavor was more obvious than before frying.

[0159] (3) After being boiled, fried, and deep-fried, Example 3 retained its shape very well without cracking.

[0160] (4) After being boiled, fried, and deep-fried, the shape retention of the comparative example 1 was good and no cracking occurred. However, due to the absence of added peanut protein, the taste and flavor evaluation results were lower than those of Example 1.

[0161] (5) Comparative Example 2 was boiled ( Figure 5 ), after frying and deep-frying, the shape retention is poor and there are slight cracks.

[0162] (6) After being boiled, fried, and deep-fried, the shape retention of the comparative example 3 was poor and cracks appeared. The reason may be that the pressure was too high, resulting in the outer skin being too thin and easy to break and leak.

[0163] (7) After being boiled, fried, and deep-fried, the shape retention of the comparative example 4 was poor and cracks appeared. The reason may be that the pressure was too low, resulting in the outer skin being not firmly sealed, the structure being not tight, and being easy to break and leak.

[0164] (8) After being boiled, fried, and deep-fried, Example 4 had poor shape retention and was slightly cracked. The reason for this may be that the vegetable filling is not as good as the aquatic filling in terms of shaping effect, and it is easy to collapse when it is too large, resulting in poor shape retention.

[0165] Comparative Example 5

[0166] If peanut protein is added when preparing tofu pudding, some of it will easily be lost, resulting in low utilization rate of the peanut protein.

[0167] Comparative Example 6

[0168] If the skin-filling ratio is 4:6, it can be shaped and retains its shape well after frying, but it is more difficult to retain its shape after boiling.

[0169] If the skin-filling ratio is 9:1, it can be shaped, but the taste is not much different from regular tofu.

[0170] Comparative Example 7

[0171] The glutamine aminotransferase in Example 1 was omitted, and the mass ratio of tofu pudding, pistachio protein, salt and xanthan gum was adjusted to 58.5:10:1:0.5. The rest was kept the same as in Example 1.

[0172] The results showed that the shape retention was better after frying, but it was difficult to retain the shape after boiling.

[0173] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for preparing thick-walled stuffed tofu with high shape retention, high moisture content and high nutrition, characterized in that: The steps include: (1) Soaking, grinding, filtering, boiling, adding brine, and allowing to settle to form tofu pudding; (2) adding nut protein, enzyme preparation, salt, and binder to the tofu pudding, mixing them evenly, and obtaining a cortex mixture; wherein the mass ratio of the tofu pudding, nut protein, enzyme preparation, salt, and binder is (38-58):(5-10):(0.5-2):(0.1-1):(0.1-0.5); (3) pouring half the volume of the skin layer mixture into the lower skin layer mold, pressing at 3-5 MPa and 30-50° C. to form the lower skin layer of stuffed tofu; (4) Add stuffing to the lower skin layer of stuffed tofu and cover it with an upper skin layer mold. Pour the other half volume of the skin layer mixture into the upper skin layer mold and press at 3-5 MPa and 30-50° C. to form an upper skin layer of stuffed tofu, thereby obtaining thick-walled stuffed tofu.

2. The method according to claim 1, characterized in that The solid content of the tofu pudding in step (1) is 30-80%.

3. The method according to claim 1, characterized in that In step (2), the nut protein is one or more of peanut protein, pistachio protein, hazelnut protein, walnut protein, and moringa seed protein.

4. The method according to claim 1, characterized in that: In step (2), the binder is one or more of gellan gum, carrageenan, tapioca starch and xanthan gum.

5. The method according to claim 1, characterized in that The mass ratio of the total skin mixture to the filling in steps (3) and (4) is (6-8):(2-4).

6. The method according to claim 1, characterized in that The filling in step (4) includes one or more of shrimp, shrimp meat, crab roe, fish meat, shrimp roe, fish roe, minced meat, shredded radish, and mashed potatoes.

7. The thick-walled stuffed tofu with high shape retention, high moisture content and high nutrition prepared by the method according to any one of claims 1 to 6.

8. Application of the thick-walled stuffed tofu according to claim 7 in the food field.

9. A kind of instant tofu, characterized in that: The thick-walled stuffed tofu according to claim 7 is adopted.

10. A method for improving the shape retention, moisture content and nutrient content of stuffed tofu, characterized in that: The steps include: (1) Soaking, grinding, filtering, boiling, adding brine, and allowing to settle to form tofu pudding; (2) adding nut protein, enzyme preparation, salt, and binder to the tofu pudding, mixing them evenly, and obtaining a cortex mixture; wherein the mass ratio of the tofu pudding, nut protein, enzyme preparation, salt, and binder is (38-58):(5-10):(0.5-2):(0.1-1):(0.1-0.5); (3) pouring half the volume of the skin layer mixture into the lower skin layer mold, pressing at 3-5 MPa and 30-50° C. to form the lower skin layer of stuffed tofu; (4) Adding stuffing to the lower skin layer of stuffed tofu and covering it with an upper skin layer mold, pouring the other half volume of the skin layer mixture into the upper skin layer mold, pressing at 3-5 MPa and 30-50° C. to form an upper skin layer of stuffed tofu, thus obtaining stuffed tofu.

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