Hydrolyzed wheat flour as well as preparation method and application thereof in flour coating

Abstract

The preparation method comprises the following steps: uniformly mixing and stirring wheat flour, drinking water and baking soda, heating to 50-60 DEG C, adding protease for hydrolysis for 1-3 hours, adjusting the pH value of enzymatic hydrolysate to 5.0-7.0, adding glucosidase for continuous hydrolysis for 1-3 hours, and performing enzyme deactivation and drying treatment to obtain the hydrolyzed wheat flour. When the hydrolyzed wheat flour is applied to flour coating, the volume of a paste-coated fried meat product is increased by more than 10%, and the oil absorption is obviously reduced by more than 15% compared with a control group. According to the invention, the problems of high oil content and lack of high-quality wrapping powder of the paste-coated fried meat product are effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of food processing, and particularly relates to a hydrolyzed wheat flour, a preparation method thereof, and an application thereof in breading. Background Art

[0002] Breading refers to a liquid mixture of water and wheat flour that is soaked before food frying, also known as batter, coating powder, frying powder, flour paste, etc. Many fried food raw materials such as shrimp, fish, chicken fillets, chicken legs, vegetables, etc. need to be evenly coated with a viscous paste (breading) on the surface of the product before frying. This process is called battering. Battering is one of the important production processes for fried meat products. This process can not only keep the moisture and flavor in the raw materials, increase the product volume, and has the characteristics of golden color, crispy outside and tender inside, but also protect its nutritional components, and thus is beneficial for the finished product to have a loose, tender, fragrant and crispy edible quality, and is deeply loved by consumers.

[0003] The composition of breading is an important factor affecting the quality of battered and fried meat products. In recent years, it has become a hot issue in the research of fried foods. The simplest breading consists of water and flour. In the actual production process, the composition of the paste can include one or more of wheat flour, wheat protein, corn starch, egg protein, soy protein, leavening agent, seasonings, food-grade hydrocolloids, and other components. Although the composition of breading has become increasingly complex, wheat flour is still one of the main components of breading.

[0004] The water content, protein content, amylose content, and amylopectin content in breading are closely related to its viscosity, oil absorption rate, and the brittleness of the product. Viscosity is a key property of battered and fried meat products, which affects the weight and quality, color, texture, and taste of the product. Therefore, the factors for evaluating battered and fried meat products include texture, moisture, oil absorption, crispness, color, taste, and nutrition. Since the start of fried breaded foods in China is relatively late, the domestic research on breading is still in its initial stage, and there is a lack of systematic theoretical research on the breading formula and production process.

[0005] With the increasing improvement of people's living standards and the gradual enhancement of health awareness in China, consumers have a certain resistance to battered and fried foods, worrying that the high oil content in fried foods is likely to cause obesity or increase the risk of cardiovascular and cerebrovascular diseases. Therefore, how to reduce the oil content of fried products and improve the edible quality is an urgent problem to be solved in the research and processing field of battered and fried meat products. On the other hand, the manufacturers of battered and fried meat products also hope that the breaded fried foods have less oil absorption and larger volume, so as to achieve the purpose of reducing production costs and making the product appearance more attractive. Therefore, developing high-quality breading can not only meet the health needs of consumers, but also has strong attraction for both breading production enterprises and manufacturers of battered and fried meat products. Summary of the Invention

[0006] To solve the above technical problems, the present invention provides a hydrolyzed wheat flour, its preparation method and application in breading. When the hydrolyzed wheat flour is applied in breading, it can reduce the oil content of fried products and improve their edible quality.

[0007] The object of the present invention is achieved by the following technical solutions:

[0008] Firstly, the present invention provides a preparation method of hydrolyzed wheat flour. Mix wheat flour, drinking water and baking soda evenly, heat up to 50 - 60 °C, add protease and hydrolyze for 1 - 3 h. After adjusting the pH value of the enzyme hydrolysis solution to 5.0 - 7.0, then add glucosidase and continue to hydrolyze for 1 - 3 h. After enzyme inactivation and drying treatment, hydrolyzed wheat flour is obtained.

[0009] Furthermore, the content of wheat protein in the wheat flour is 12 - 16%.

[0010] Furthermore, the addition amount of the protease is 0.01 - 0.05% of the mass of the wheat flour. The protease is at least one of Novozymes (China) Co., Ltd. 37071, Novozymes (China) Co., Ltd. Protamex, AB Enzyme Preparation Company 7089, AB Enzyme Preparation Company APC, porcine-derived trypsin, Amano Enzyme Preparation Co., Ltd. ProteAXH, Amano Enzyme Preparation Co., Ltd. AY50C, Angel Enzyme Preparation Company alkaline protease, Shin Nippon Chemical Co., Ltd. FPG.

[0011] Furthermore, the addition amount of the glucosidase is 0.05 - 0.5% of the mass of the wheat flour. The glucosidase is Shin Nippon Chemical Co., Ltd. Sumizyme-G_2 or Novozymes (China) Co., Ltd. GA.

[0012] Furthermore, the addition amount of the drinking water is 200 - 500% of the mass of the wheat flour.

[0013] Furthermore, the addition amount of the baking soda is 0.3 - 1.0% of the mass of the wheat flour.

[0014] Furthermore, the temperature of the enzyme inactivation treatment is 80 - 95 °C, and the time is 15 - 30 min.

[0015] Furthermore, the average molecular weight of the protein in the hydrolyzed wheat flour is less than 10 kDa.

[0016] Secondly, the present invention provides a hydrolyzed wheat flour, which is prepared by the above preparation method of hydrolyzed wheat flour.

[0017] Thirdly, the present invention provides an application of hydrolyzed wheat flour in breading, and the addition amount of the hydrolyzed wheat flour is 20-50% of the total mass of the breading.

[0018] The beneficial effects of the present invention are as follows:

[0019] 1. After the hydrolyzed wheat flour of the present invention is enzymatically hydrolyzed, the internal molecular structure thereof changes, forming some structures that can hinder the entry of oil into the product, thereby effectively reducing the oil content of the fried product and meeting the needs of consumers for healthy foods. By applying the hydrolyzed wheat flour to the breading, the structure and properties of the breading can be changed, so that the fried product absorbs less oil during the frying process. When the hydrolyzed wheat flour of the present invention is applied to the breading, the oil adsorption amount is reduced by more than 15%, which not only meets the pursuit of consumers for low oil content in healthy foods, but also helps the manufacturer reduce production costs.

[0020] 2. The hydrolyzed wheat flour obtained by a specific preparation method of the present invention is applied to the breading, which can significantly increase the volume of the batter-fried meat products. Experimental data show that it can be increased by more than 10%, meeting the needs of manufacturers to increase the volume of products.

[0021] 3. The preparation method of the hydrolyzed wheat flour of the present invention is simple, easy to operate, suitable for large-scale production applications, and has strong attractiveness and practical application value for both breading production enterprises and batter-fried meat product manufacturers. Specific Embodiments

[0022] To further understand the present invention, the preferred embodiments of the present invention will be described below in conjunction with examples. However, it should be understood that these descriptions are only for further explaining the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0023] It should be particularly noted that those not specified below are carried out according to conventional conditions or conditions recommended by the manufacturer. The raw materials, reagents, etc. used without indicating the manufacturer can be obtained as conventional products through commercial purchase.

[0024] The experimental methods for the test indexes involved in the embodiments of the present invention are as follows:

[0025] Measurement of the volume of batter-fried meat products: After batter-frying meat products of the same weight before frying, put the batter-fried meat products into a graduated cylinder, and record the change in the volume of water in the graduated cylinder before and after putting them in after 1 minute.

[0026] Volume increase ratio = [(V1 - V2) after frying / (V1 - V2) before frying - 1] * 100%, where:

[0027] V1 is the reading of the volume of water in the graduated cylinder after putting the batter-fried meat products in,

[0028] V2 is the reading of the volume of water in the graduated cylinder before putting the batter-fried meat product into the graduated cylinder 1 minute later.

[0029] Determination of the oil absorption of the breading after frying: After carefully peeling the breading on the surface of the batter-fried meat product from the meat product, the Soxhlet extraction method is used to determine the oil absorption of the breading after frying, calculated as % or g / 100g of breading.

[0030] The present invention will be further described below in conjunction with specific embodiments.

[0031] 1. Analysis of the oil absorption of the breading with different protease dosages under the same conditions

[0032] After mixing 100 g of wheat flour (protein content 12%) evenly with 300 g of drinking water and 1 g of baking soda, 0 g, 0.01 g, 0.02 g, 0.03 g, 0.04 g, and 0.05 g of Novozymes 37071 protease are added respectively. After hydrolysis at 50 °C for 3 h, the pH value of the hydrolysate is adjusted to 5.0, inactivated at 80 °C for 30 min, and spray-dried to obtain hydrolyzed wheat flour No. 1, hydrolyzed wheat flour No. 2, hydrolyzed wheat flour No. 3, hydrolyzed wheat flour No. 4, hydrolyzed wheat flour No. 5, and hydrolyzed wheat flour No. 6 in sequence.

[0033] Prepare the breading by mixing hydrolyzed wheat flour Nos. 1-6 with drinking water at a ratio of 1:2. Put the cut meat pieces into the breading, take them out, fry them, and determine the oil absorption of the breading after frying, as shown in Table 1.

[0034] Table 1

[0035] Number Oil absorption Number Oil absorption Hydrolyzed wheat flour No. 1 34.8％ Hydrolyzed wheat flour No. 2 29.5％ Hydrolyzed wheat flour No. 3 28.6％ Hydrolyzed wheat flour No. 4 28.7％ Hydrolyzed wheat flour No. 5 26.9％ Hydrolyzed wheat flour No. 6 26.9％

[0036] As can be seen from Table 1, the oil absorption of the wheat flour without protease hydrolysis (hydrolyzed wheat flour No. 1) is 34.8%, and the oil absorption of the hydrolyzed wheat flour Nos. 2-6 prepared by adding protease is between 26.9% and 29.5%, which is more than 5% lower than that of hydrolyzed wheat flour No. 1.

[0037] 2. Analysis of the oil absorption of the breading under the action of different proteases under the same conditions

[0038] After mixing 100 g of wheat flour (protein content 15%) evenly with 500 g of drinking water and 0.8 g of baking soda, 0 g of protease, 0.05 g of Protamex, 0.05 g of AB Enzyme Preparation Company 7089, 0.05 g APC, 0.05 g of porcine-derived trypsin, 0.05 g of ProteAXH from Amano Enzyme Inc., 0.05 g of AY50C, 0.05 g of alkaline protease from Angel Enzyme Co., Ltd., and 0.05 g of FPG from Shin Nippon Chemical Co., Ltd. After hydrolysis at 60 °C for 1 h, the pH value of the enzymatic hydrolysate was adjusted to 7.0, inactivated at 95 °C for 15 min, and spray-dried to obtain hydrolyzed wheat flour No. 7, hydrolyzed wheat flour No. 8, hydrolyzed wheat flour No. 9, hydrolyzed wheat flour No. 10, hydrolyzed wheat flour No. 11, hydrolyzed wheat flour No. 12, hydrolyzed wheat flour No. 13, hydrolyzed wheat flour No. 14, and hydrolyzed wheat flour No. 15 in sequence.

[0039] The hydrolyzed wheat flours No. 7 - 15 were respectively mixed with drinking water at a ratio of 1:2 to prepare breading. The cut meat blocks were put into the breading, taken out, and fried, and the oil absorption of the fried breading was measured, as shown in Table 2.

[0040] Table 2

[0041] Number Oil absorption Number Oil absorption Hydrolyzed wheat flour No. 7 32.9％ Hydrolyzed wheat flour No. 8 26.2％ Hydrolyzed wheat flour No. 9 27.4％ Hydrolyzed wheat flour No. 10 26.8％ Hydrolyzed wheat flour No. 11 27.0％ Hydrolyzed wheat flour No. 12 26.5％ Hydrolyzed wheat flour No. 13 27.1％ Hydrolyzed wheat flour No. 14 25.9％ Hydrolyzed wheat flour No. 15 26.4％

[0042] As can be seen from Table 2, the oil absorption of the wheat flour without protease hydrolysis (hydrolyzed wheat flour No. 7) was 32.9%, and the oil absorption of the hydrolyzed wheat flours No. 8 - 15 prepared by adding protease was between 25.9% and 27.4%, which was reduced by more than 5% compared with hydrolyzed wheat flour No. 7.

[0043] 3. Under the same conditions, analysis of the volume increase value and the oil absorption of the breading under the synergistic action of protease and different contents and different glucosidases

[0044] 100 g of wheat flour (protein content 12%) was mixed evenly with 200 g of drinking water and 0.3 g of baking soda, then 0.05 g of protease 37071 from Novozymes was added. After hydrolysis at 55 °C for 2 h, the pH value of the enzymatic hydrolysate was adjusted to 6.0. Then 0 g of glucosidase, 0.05 g, 0.1 g, 0.5 g of Sumizyme-G_2 from Shin Nippon Chemical Co., Ltd., and 0.05 g, 0.1 g, 0.5 g of glucosidase from Novozymes (China) Co., Ltd. were respectively added. After hydrolysis at 55 °C for 3 h, inactivated at 85 °C for 30 min, and spray-dried to obtain hydrolyzed wheat flour No. 16, hydrolyzed wheat flour No. 17, hydrolyzed wheat flour No. 18, hydrolyzed wheat flour No. 19, hydrolyzed wheat flour No. 20, hydrolyzed wheat flour No. 21, and hydrolyzed wheat flour No. 22 in sequence.

[0045] Mix the hydrolyzed wheat flours No. 16 - 22 above with drinking water at a ratio of 1:2 respectively to prepare breading. Put the cut meat pieces into the breading, take them out, and then fry them. Measure the volume increase value of the battered and fried meat products and the oil absorption of the breading after frying. In addition, for comparison, mix 100 g of wheat flour (protein content 12%) with 200 g of drinking water to prepare breading, which is wheat flour No. 1, and test the volume increase value of its battered and fried meat products and the oil absorption of the breading after frying. The results are shown in Table 3.

[0046] Table 3

[0047] Number Volume increase ratio Oil absorption Wheat flour No. 1 0％ 36.9％ Hydrolyzed wheat flour No. 16 0％ 26.4％ Hydrolyzed wheat flour No. 17 12.7％ 17.5％ Hydrolyzed wheat flour No. 18 13.5％ 16.8％ Hydrolyzed wheat flour No. 19 14.9％ 16.0％ Hydrolyzed wheat flour No. 20 11.1％ 14.7％ Hydrolyzed wheat flour No. 21 12.4％ 15.1％ Hydrolyzed wheat flour No. 22 16.8％ 15.9％

[0048] As can be seen from Table 3, taking the hydrolyzed wheat flour without glucosidase hydrolysis treatment (hydrolyzed wheat flour No. 16) as a control, the volume increase values of hydrolyzed wheat flours No. 17 - 22 prepared after adding Sumizyme - G_2 of Shin Nippon Chemical Co., Ltd. and glucosidase of Novozymes (China) Co., Ltd. are between 11.1% and 16.8%. This indicates that adding glucosidase treatment during the hydrolysis of wheat flour can significantly increase the volume of battered and fried meat products by more than 10%. At the same time, the oil absorption of hydrolyzed wheat flours No. 16 - 22 prepared by adding protease and glucosidase simultaneously is between 14.7% and 17.5%, which is significantly reduced by more than 15% compared with wheat flour No. 1, hydrolyzed wheat flour No. 1, and hydrolyzed wheat flour No. 7.

[0049] Through the comparative analysis of the above - mentioned examples, it can be seen that the hydrolyzed wheat flour prepared by the present invention can be applied to breading, which can effectively increase the volume of battered and fried meat products and reduce the oil absorption, showing good application effects.

[0050] According to the disclosure of the above - mentioned specification, those skilled in the art of the present invention can also make appropriate changes and modifications to the above - mentioned embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims

1. A method for preparing hydrolyzed wheat flour, characterized in that: The wheat flour, drinking water and baking soda are mixed and stirred evenly, the temperature is raised to 50-60° C., protease is added to hydrolyze for 1-3 hours, the pH value of the enzymatic hydrolyzate is adjusted to 5.0-7.0, glucosidase is added to continue hydrolyzing for 1-3 hours, and then the enzyme is inactivated and dried to obtain hydrolyzed wheat flour.

2. The method for preparing hydrolyzed wheat flour according to claim 1, characterized in that: The content of wheat protein in the wheat flour is 12-16%.

3. The method for preparing hydrolyzed wheat flour according to claim 1, characterized in that: The amount of the protease added is 0.01-0.05% of the mass of the wheat flour. The protease is Novozymes (China) Co., Ltd. 37071, Novozymes (China) Co., Ltd. Protamex, AB Enzyme Preparation Company 7089, AB Enzyme Preparation Company At least one of APC, porcine trypsin, ProteAXH from Amano Enzyme Co., Ltd., AY50C from Amano Enzyme Co., Ltd., alkaline protease from Angel Enzyme Co., Ltd., and FPG from Shin Nippon Chemical Co., Ltd.

4. The method for preparing hydrolyzed wheat flour according to claim 1, characterized in that: The amount of glucosidase added is 0.05-0.5% of the mass of wheat flour. The glucosidase is Sumizyme-G_2 from New Nippon Chemical Co., Ltd. or Novozymes (China) Co., Ltd. GA.

5. The method for preparing hydrolyzed wheat flour according to claim 1, characterized in that: The amount of drinking water added is 200-500% of the mass of the wheat flour.

6. The method for preparing hydrolyzed wheat flour according to claim 1, characterized in that: The added amount of baking soda is 0.3-1.0% of the mass of wheat flour.

7. The method for preparing hydrolyzed wheat flour according to claim 1, characterized in that: The temperature of the enzyme inactivation treatment is 80-95° C. and the time is 15-30 minutes.

8. The method for preparing hydrolyzed wheat flour according to claim 1, characterized in that: The average molecular weight of the protein in the hydrolyzed wheat flour is less than 10 kDa.

9. A hydrolyzed wheat flour, characterized in that: The hydrolyzed wheat flour is prepared by the method for preparing the hydrolyzed wheat flour according to any one of claims 1 to 8.

10. The use of the hydrolyzed wheat flour in flour coating according to claim 9, characterized in that: The added amount of the hydrolyzed wheat flour is 20-50% of the total weight of the flour.