A processing method for reducing beany smell of soybean textured protein and soybean textured protein

Abstract

The present invention belongs to the technical field of plant raw material processing, and specifically relates to a processing method and soybean textured protein for reducing the beany smell of soybean textured protein. The processing method includes: (1) homogenization: fully mixing soybean protein isolate, green tea powder, baking soda and water with a food processor, emulsifying, and obtaining a soybean protein isolate green tea powder slurry; (2) powder mixing: fully mixing and stirring the soybean protein isolate green tea powder slurry in step (1) with gluten powder and rosemary powder; (3) extrusion: uniformly adding the mixed raw materials in step (2) into a twin-screw extruder for extrusion, with independent three-stage temperature control; (4) puffing: the raw materials after extrusion in step (3) enter the puffing section. The present invention starts with the composition and structure of soybean protein, and the addition of natural plant raw materials green tea powder and rosemary powder effectively reduces the beany smell of soybean textured protein.

Description

Technical Field

[0001] The invention belongs to the technical field of plant raw material processing, and particularly relates to a processing method for reducing the beany smell of soybean textured protein and soybean textured protein. Background Art

[0002] At present, the global crop protein output is about 550 million tons, of which only 40% can reach the human table, and 45% is used for animal feed products. The global population and protein demand are still increasing. Since there is almost no arable land for expansion, the protein demand gap problem needs to be solved by improving the utilization efficiency of plant protein. Among them, plant-based artificial meat is a rapidly developing product with the advantages of high protein, low fat, no hormones and veterinary drug residues, etc. The tissue protein produced by extrusion technology has achieved a taste similar to animal meat, so it has broad development prospects.

[0003] Soy protein is one of the most commercialized plant proteins and the main raw material for making textured protein, but its unique beany smell limits the application of soy protein and soy textured protein. The main source of soybean beany smell is the oxidation of unsaturated fatty acids catalyzed by lipoxygenase to form carbonyl compounds, which are further degraded into small molecular volatile compounds, mainly including fatty aldehydes, fatty ketones, fatty alcohols, furans and furan derivatives. Therefore, an effective processing method is needed to reduce the generation of beany smell-related compounds and / or better remove beany smell-related compounds in the product.

[0004] At present, there are three main methods to reduce the beany smell of soy textured protein: the first is to use soy protein produced from soybean varieties with lower beany smell. This method is more strict in the screening of soybean raw materials and the overall protein yield is also limited; the second is to use heating passivation during the processing of soy protein to inhibit the lipoxygenase in soybeans. This method is complex and easily leads to denaturation and aggregation of protein structure, and the effect of removing the beany smell is not good; the third method is to add flavoring substances during the processing of soy textured protein or during the post-processing of soy textured protein to eliminate or mask the beany smell of soy textured protein. This method has a poor masking effect, and the beany smell is still present after chewing, and additional processing is added. Summary of the invention

[0005] In view of the above problems existing in the prior art, the present invention aims to provide a processing method for reducing the beany smell of soybean textured protein and a soybean textured protein product with reduced beany smell obtained by the method.

[0006] The specific technical solutions include the following:

[0007] First, the present invention provides a processing method for reducing the beany smell of soybean textured protein, comprising the following steps:

[0008] (1) Homogenization: The soy protein isolate, green tea powder, baking soda and water are fully mixed and emulsified using a food processor to obtain a soy protein isolate-green tea powder slurry;

[0009] (2) Mixing powder: fully mixing the soy protein isolate-green tea powder slurry in step (1) with gluten powder and rosemary powder;

[0010] (3) Extrusion: The raw materials mixed in step (2) are uniformly added into a twin-screw extruder for extrusion, with independent three-stage temperature control;

[0011] (4) Puffing and forming: After extrusion, it enters the puffing and forming section.

[0012] Preferably, in step (1), by weight: 28.9-33.7 parts of soy protein isolate, 40 parts of water, 1-4 parts of green tea powder and 0.1-0.3 parts of baking soda are fully homogenized in a food processor.

[0013] Preferably, in step (1), the speed of the food processor is 600-900 r / min, and the cooking time is 2-4 min.

[0014] Preferably, in step (2), by weight: 70-78 parts of soy protein isolate-green tea powder slurry, 19-28 parts of gluten and 1-2 parts of rosemary powder are fully mixed in a mixer and then added to a solid feeder.

[0015] Preferably, in step (3), the first, second and third sections of the extruder in the direction from the feed port to the discharge port are temperature controlled, and the temperatures are 110°C-120°C, 140°C-150°C and 130°C-140°C respectively, and the extruder speed is 18-25r / min.

[0016] Preferably, in step (4), the outlet of the extruder is connected to a puffing section, the temperature of the puffing section can be controlled by water, the water temperature is controlled at 80-100°C, and the length of the puffing section is 1-1.5m.

[0017] Furthermore, the present invention also provides soybean textured protein with reduced beany flavor obtained by the processing method.

[0018] Analysis of the interaction between materials in the above processing methods and the impact of processing steps on the product shows that:

[0019] First, before the materials are put into the extruder, the green tea powder, soy protein and water are subjected to high-speed homogenization treatment to fully and evenly embed the green tea powder in the soy protein emulsion. As a natural small molecule active substance, epigallocatechin gallate in the green tea powder has a regulatory effect on the structure of soy protein. The action modes include disulfide bonds, hydrogen bonds, ionic bonds, hydrophobic bonds and covalent bonds, etc., and an important composite system can be formed between the green tea powder and the soy protein to improve the structure of the protein.

[0020] Secondly, after the baking soda is evenly dispersed in the material system, the baking soda can decompose and produce gas under the conditions of water and high temperature during the extrusion process, forming uniform small air chambers in the protein system. After the tissue protein is extruded, a certain puffing effect is formed, which can discharge the volatile bean smell gas inside the tissue protein.

[0021] Again, the main chemical components of green tea powder are catechins, flavonoids, anthocyanins and phenolic acids. The important components of rosemary powder are rosmarinol, caryophyllene and rosemary dialdehyde, all of which are highly effective antioxidants and have good high temperature resistance. They can effectively block the oxidation process of soy protein during the extrusion process, provide uniform and continuous antioxidant effects, reduce the degree of oxidation of soy protein, and reduce the generation of beany substances.

[0022] In addition, the traditional extrusion puffing section uses cooling water for rapid cooling, which will cause the outer layer of the tissue protein to cool quickly, forming a dense "protein skin" structure, and the volatile beany smell gas cannot be discharged, which has a negative impact on the flavor of the tissue protein. The outlet of the extruder of the present invention is connected to the puffing section. In the process of forming the tissue protein, the protein fluid adopts a high-temperature molding method to prevent the formation of the "protein skin" structure, so that the volatile beany smell gas inside the tissue protein can be effectively discharged.

[0023] Therefore, in summary, the soybean textured protein obtained by the processing method of the present invention has the following beneficial effects: the present invention starts from the composition and structure of soybean protein, and the addition of natural plant raw materials green tea powder and rosemary powder effectively reduces the beany smell of soybean textured protein; baking soda and the puffing molding section at the outlet of the extruder promote the discharge of volatile beany smell gas, thereby reducing the negative impact of beany smell on the textured protein product and expanding its use scenarios. Moreover, the soybean textured protein obtained by the present invention has a good fiber structure, a taste similar to real meat, and a certain degree of puffing, which is conducive to subsequent processing such as drying and seasoning. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is specifically described below in conjunction with embodiments.

[0025] Embodiment 1:

[0026] (1) Homogenization: 2890 g of soy protein isolate, 4000 g of water, 100 g of green tea powder and 10 g of baking soda were fully homogenized in a food processor at a speed of 600 r / min for 3 min;

[0027] (2) Mixing powder: 7000 g of homogenized soy protein isolate-tea powder slurry, 2800 g of gluten powder and 200 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0028] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 120°C, 150°C and 140°C, and the speed is 25 r / min;

[0029] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 100°C and a length of 1.5m.

[0030] Embodiment 2:

[0031] (1) Homogenization: 3370 g of soy protein isolate, 4000 g of water, 400 g of green tea powder and 30 g of baking soda were fully homogenized in a food processor at a speed of 900 r / min for 2 min;

[0032] (2) Mixing powder: 7800 g of homogenized soy protein isolate-tea powder slurry, 2100 g of gluten powder and 100 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0033] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 115°C, 145°C and 135°C, and the speed is 18 r / min;

[0034] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 80°C and a length of 1m.

[0035] Embodiment 3:

[0036] (1) Homogenization: 3080 g of soy protein isolate, 4000 g of water, 250 g of green tea powder and 20 g of baking soda were fully homogenized in a food processor at a speed of 700 r / min for 4 min;

[0037] (2) Mixing powder: 7350 g of homogenized soy protein isolate-tea powder slurry, 2500 g of gluten powder and 150 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0038] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 110°C, 140°C and 135°C, and the speed is 22 r / min;

[0039] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 90°C and a length of 1.2m.

[0040] The following comparative examples compare and illustrate the addition of green tea powder, the addition of rosemary, the order of adding raw materials, the process parameters of puffing and extrusion, and the addition of baking soda.

[0041] Comparative Example 1:

[0042] (1) Homogenization: 3190 g of soy protein isolate, 4000 g of water and 10 g of baking soda were fully homogenized in a food processor at a speed of 700 r / min for 3 min;

[0043] (2) Mixing powder: 7200 g of homogenized soy protein isolate slurry, 2600 g of gluten powder and 200 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0044] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 120°C, 150°C and 140°C, and the speed is 25 r / min;

[0045] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 100°C and a length of 1.5m.

[0046] Comparative Example 2:

[0047] (1) Homogenization: 3370 g of soy protein isolate, 4000 g of water, 400 g of green tea powder and 30 g of baking soda were fully homogenized in a food processor at a speed of 900 r / min for 2 min;

[0048] (2) Mixing powder: 7800 g of homogenized soy protein isolate-tea powder slurry and 2200 g of gluten powder are fully mixed in a mixer and then added to a solid feeder;

[0049] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 115°C, 145°C and 135°C, and the speed is 19 r / min;

[0050] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 110°C and a length of 1m.

[0051] Comparative Example 3:

[0052] (1) Homogenization: 3280 g of soy protein isolate, 4000 g of water and 20 g of baking soda were fully homogenized in a food processor at a speed of 750 r / min for 4 min;

[0053] (2) Mixing powder: 7300 g of homogenized soy protein isolate slurry and 2700 g of gluten powder were fully mixed in a mixer and added to a solid feeder;

[0054] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 110°C, 140°C and 135°C, and the speed is 22 r / min;

[0055] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 90°C and a length of 1.2m.

[0056] Comparative Example 4:

[0057] (1) Mixing powder: 2890 g of soy protein isolate, 4000 g of water, 100 g of green tea powder, 10 g of baking soda, 2800 g of gluten powder and 200 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0058] (2) Extrusion: twin-screw extrusion, the three-stage temperatures are 120°C, 150°C and 140°C, and the speed is 25 r / min;

[0059] (3) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 100°C and a length of 1.5m.

[0060] Comparative Example 5:

[0061] (1) Homogenization: 3370 g of soy protein isolate, 4000 g of water, 200 g of green tea powder and 30 g of baking soda were fully homogenized in a food processor at a speed of 900 r / min for 2 min;

[0062] (2) Mixing powder: 7600 g of homogenized soy protein isolate-tea powder slurry, 2300 g of gluten powder and 100 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0063] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 115°C, 145°C and 135°C, and the speed is 18 r / min;

[0064] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 70°C and a length of 1.3m.

[0065] Comparative Example 6:

[0066] (1) Homogenization: 3080 g of soy protein isolate, 4000 g of water, 350 g of green tea powder and 20 g of baking soda were fully homogenized in a food processor at a speed of 700 r / min for 4 min;

[0067] (2) Mixing powder: 7450 g of homogenized soy protein isolate-tea powder slurry, 2400 g of gluten powder and 150 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0068] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 115°C, 150°C and 135°C, and the speed is 23 r / min;

[0069] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 90°C and a length of 0.9m.

[0070] Comparative Example 7:

[0071] (1) Homogenization: 3000 g of soy protein isolate, 4000 g of water, 250 g of green tea powder and 20 g of baking soda were fully homogenized in a food processor at a speed of 700 r / min for 4 min;

[0072] (2) Mixing powder: 7270 g of homogenized soy protein isolate-tea powder slurry, 2580 g of gluten powder and 150 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0073] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 130°C, 160°C and 150°C, and the speed is 20 r / min;

[0074] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 95°C and a length of 1.1m.

[0075] Comparative Example 8:

[0076] (1) Homogenization: 3000 g of soy protein isolate, 4000 g of water and 100 g of green tea powder were fully homogenized in a food processor at a speed of 800 r / min for 3 min;

[0077] (2) Mixing powder: 7100 g of homogenized soy protein isolate-tea powder slurry, 2800 g of gluten powder and 100 g of rosemary powder were fully mixed in a mixer and added to a solid feeder;

[0078] (3) Extrusion: twin-screw extrusion, the three-stage temperatures are 120°C, 150°C and 140°C, and the speed is 25 r / min;

[0079] (4) Extrusion molding: After extrusion, it enters the expansion molding section with a water temperature of 100°C and a length of 1.4m.

[0080] The textured proteins prepared in Examples 1-3 and Comparative Examples 1-8 were subjected to sensory evaluation, and the sensory evaluation criteria are shown in Table 1, and the sensory evaluation results are shown in Table 2. The samples were subjected to beany smell analysis of the soy protein extrudates using gas chromatography-olfaction-mass spectrometry (GC-O-MS), and the aroma activity value of each beany smell compound was calculated, and the concentrations of 6 main beany smell-related compounds were screened out, as shown in Table 3.

[0081] Table 1 Sensory scoring criteria

[0082]

[0083] The sensory evaluation was conducted by a professional evaluation team of 5 people, and Table 3 shows the average values.

[0084] Table 2 Sensory evaluation results

[0085] Degree of organization Beany smell evaluation Total score Example 1 9.1 8.8 17.9 Example 2 8.5 9.0 17.5 Example 3 8.8 8.4 17.2 Comparative Example 1 7.3 6.4 13.5 Comparative Example 2 7.7 5.9 13.6 Comparative Example 3 6.2 4.8 11 Comparative Example 4 6.0 5.6 11.6 Comparative Example 5 5.1 7.1 12.2 Comparative Example 6 4.3 7.5 11.8 Comparative Example 7 3.2 5.7 8.9 Comparative Example 8 7.2 5.1 12.3

[0086] Table 3 Concentrations of major beany smell compounds in tissue protein (ng / g)

[0087]

[0088] Table 2 shows the sensory evaluation results of the tissue protein samples of the examples and comparative examples from two main aspects: the degree of organization and the beany smell. Examples 1-3 all obtained tissue proteins with a good degree of organization and a low beany smell.

[0089] In Comparative Examples 1 and 4, green tea powder was not fully dispersed in the soy protein isolate in advance, resulting in the inability of green tea powder to fully react with soy protein during the extrusion process, resulting in poor beany smell evaluation and organization degree. In Comparative Example 2, no rosemary powder was added, and in Comparative Example 3, no tea powder and rosemary powder were added. The beany smell was not well suppressed, and there was no promoting effect on the formation of the tissue protein. In Comparative Examples 5 and 6, the too low forming section temperature resulted in insufficient expansion of the tissue protein, and the volatile beany smell gas in the tissue protein could not be discharged, but the too short puffing forming section did not constrain the material system after being extruded from the extruder, resulting in excessive expansion of the tissue protein, destroying the integrity of the tissue protein. In Comparative Example 7, the extrusion temperature was too high, resulting in the destruction of the extrusion system. In Comparative Example 8, no baking soda was added, the gas production capacity inside the tissue protein was insufficient, the volatile beany smell gas could not be discharged well, and uneven organization occurred. Six volatile compounds such as 2-n-pentylfuran with high concentrations will have an adverse effect on tissue protein. As shown in Table 3, the main compounds related to the beany smell in the embodiments and comparative examples were analyzed by GC-O-MS technology. Through this processing method and the addition of tea powder and rosemary powder, the content of these compounds in the product can be significantly reduced, thereby reducing the beany smell of tissue protein.

Claims

1. A processing method for reducing the beany smell of soybean textured protein, characterized in that: This is accomplished by the following steps: (1) Homogenization: Soy protein isolate, green tea powder, baking soda and water are fully mixed and emulsified using a food processor, and the green tea powder is fully and evenly embedded in the soy protein emulsion to obtain a soy protein isolate-green tea powder slurry; (2) Mixing powder: fully mixing the soy protein isolate-green tea powder slurry in step (1) with gluten powder and rosemary powder; (3) Extrusion: The raw materials mixed in step (2) are uniformly added into a twin-screw extruder for extrusion, and the mixture is controlled by three independent temperature stages; (4) Puffing and forming: the raw material after extrusion in step (3) enters the puffing and forming section; In the step (4), the outlet of the extruder is connected to an expansion molding section, the expansion molding section can be temperature-controlled by water, the water temperature is controlled at 80-100° C., and the length of the expansion molding section is 1-1.5 m; In the step (1), by weight: 28.9-33.7 parts of soy protein isolate, 40 parts of water, 1-4 parts of green tea powder, and 0.1-0.3 parts of baking soda are fully homogenized in a food processor; In the step (2), by weight: 70-78 parts of soy protein isolate-green tea powder slurry, 19-28 parts of gluten, and 1-2 parts of rosemary powder are fully mixed in a mixer and then added to a solid feeder; In the step (3), the first, second and third sections of the extruder from the feed port to the discharge port are temperature controlled at 110°C-120°C, 140°C-150°C, 135-140°C, respectively, and the extruder speed is 18-25 rpm.

2. The method for reducing the beany smell of soybean textured protein according to claim 1, wherein in the step (1), the speed of the food processor is 600-900 r / min and the time is 2-4 min.

3. A textured soybean protein product with reduced beany flavor obtained by the processing method according to any one of claims 1 to 2.

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