High-dietary-fiber coarse millet thick pulp and preparation method thereof

Abstract

The embodiment of the invention discloses high-dietary-fiber coarse millet thick pulp and a preparation method thereof. The method comprises the following steps: taking whole grain coarse millet, wheat bran and water as raw materials, and sequentially carrying out mixing, gelatinization, liquefaction, saccharification, enzymolysis, homogenization, additive addition and sterilization treatment to obtain the coarse millet thick slurry with high dietary fiber content. By optimizing the raw material formula and innovating the preparation technology, the content of dietary fibers in the coarse millet thick pulp is increased, meanwhile, other nutritional ingredients are reserved to the maximum extent, the stability and taste of the product are improved, and the requirements of consumers for the coarse millet thick pulp product which is high in dietary fiber content, rich in nutrition and good in taste are met.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of food processing, and in particular to a high-dietary-fiber brown millet slurry and a preparation method thereof. Background Art

[0002] Millet syrup is a liquid food made from millet as the main raw material. It combines the nutritional properties of millet with a convenient way of consumption. As people's health awareness increases, the demand for functional foods with high nutritional value is increasing day by day. As a convenient and nutritious food form, millet syrup has broad market prospects. Existing millet syrups are usually made from grains (such as millet, oats, coix seed, buckwheat, etc.) as raw materials and are made into finished products through steps such as enzymatic hydrolysis or fermentation. There are many quality issues that need to be addressed:

[0003] In terms of nutritional content indicators, the total dietary fiber of millet pulp is difficult to reach the ideal standard, which greatly reduces the nutritional richness of the product. It is unable to fully exert the functions of dietary fiber in promoting intestinal motility, reducing the risk of cardiovascular disease, regulating blood sugar, etc., and it is difficult to meet consumers' pursuit of high-fiber healthy food.

[0004] From a product stability perspective, due to the high total solids and starch content of millet slurry, water precipitation and sedimentation are prone to occur during storage. Water gradually separates from the originally uniform slurry system, and insoluble solid particles settle under gravity, resulting in significant stratification of the product, disrupting its uniformity and affecting its appearance and eating experience. Furthermore, the aging of the starch in the millet slurry can cause the slurry to form a weak gel, changing the product's original fluid state, affecting its fluidity and taste, and significantly shortening its shelf life, causing inconvenience in production, sales, and consumer use.

[0005] In view of this, it is necessary to conduct in-depth research on the preparation method of millet slurry to improve product quality. Summary of the Invention

[0006] To this end, the embodiment of the present invention provides a high-dietary fiber brown millet slurry and a preparation method thereof, so as to solve the problems in the prior art that the nutrient content index of the brown millet slurry does not meet the standards and the product stability is poor.

[0007] In order to achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0008] According to a first aspect of an embodiment of the present invention, the present invention provides a method for preparing a high-dietary fiber brown millet concentrate, the method comprising: using whole grain brown millet, wheat bran and water as raw materials, sequentially mixing, gelatinizing, liquefying, saccharifying, enzymolysis, homogenizing, adding additives, and sterilizing to obtain the high-dietary fiber brown millet concentrate.

[0009] Furthermore, the wheat bran is enzyme-inactivated wheat bran, and the enzyme-inactivating conditions are: microwave 700-900W, 1-2min; the mass ratio of the whole grain brown millet, wheat bran and water is 4:1-1.5:35-40;

[0010] Furthermore, the gelatinization conditions are: stirring at a temperature of 85-95° C. for 8-12 minutes.

[0011] Furthermore, the liquefaction includes: adding 0.035-0.045% by mass of α-amylase to the gelatinized mixture, and stirring for 50-60 minutes at a temperature of 50-60° C. and a pH of 5.0-7.0.

[0012] Furthermore, the saccharification includes: adding 0.10-0.12% by weight of glucoamylase to the liquefied mixture, and stirring for 50-60 minutes at a temperature of 55-60° C. and a pH of 3.5-6.0.

[0013] Furthermore, the enzymatic hydrolysis comprises: adding 0.05-0.10% by mass of papain to the saccharified mixture, and stirring for 1-4 hours at a temperature of 45-55° C. and a pH of 5.0-11.0.

[0014] Furthermore, the homogenization condition is: homogenization 1-2 times at a pressure of 30-50 MPa.

[0015] Furthermore, the additives include xanthan gum and xylitol; the added amount of the xanthan gum is 0.2-0.3%, and the added amount of the xylitol is 0.5-2.5%.

[0016] Furthermore, the sterilization conditions are: temperature 121° C., pressure 103 kPa, sterilization for 1-10 minutes.

[0017] According to a second aspect of the embodiments of the present invention, the present invention provides a high dietary fiber brown millet slurry, which is prepared by the method described in any one of the above items.

[0018] The embodiments of the present invention have the following advantages:

[0019] The concentrated slurry product prepared using whole-grain unpolished millet and wheat bran, combined with bio-enzymatic hydrolysis and homogenization techniques, has a total solids content and total dietary fiber content that meet the requirements of China's light industry standard QB / T4221-2011. The total dietary fiber content of the product is ≥3g / 420kJ, which also meets the requirement of GB 28050-2025 for products claiming to be "high or rich in dietary fiber or a good source." Furthermore, the product has excellent storage stability, exhibiting no signs of water precipitation, precipitation, stratification, or weak gelation during its shelf life, and exhibits excellent sensory quality.

[0020] The present invention selects whole grain brown millet as raw material, thereby avoiding nutrient loss caused by excessive processing; selects wheat bran as raw material, thereby fully utilizing the nutritional value of grain processing by-products, and has good application prospects. DETAILED DESCRIPTION

[0021] The following describes the implementation of the present invention using specific embodiments. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. Obviously, the embodiments described are only a portion of the present invention, not all of it. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0022] Example 1

[0023] This embodiment provides a high dietary fiber brown millet slurry, the preparation method of which comprises the following steps:

[0024] (1) Whole grain brown millet and wheat bran treated with microwave enzyme inactivation (800W, 2min) were selected as raw materials;

[0025] (2) The rough millet was crushed and passed through an 80-mesh sieve, and then mixed with millet flour, wheat bran, and water in a mass ratio of 4:1:40 and stirred evenly;

[0026] (3) The mixture was gelatinized at 90°C for 8 min;

[0027] (4) After gelatinization, α-amylase was added at a mass of 0.04% of the mixed solution, and liquefied at a temperature of 50°C and a pH of 6.0 for 50 minutes;

[0028] (5) After liquefaction, glucoamylase was added at a mass ratio of 0.12% of the mass of the mixed solution, and saccharification was carried out at a temperature of 60° C. and a pH of 3.5 for 60 min;

[0029] (6) After saccharification, 0.05% of the mass of the mixed solution was added with papain, and enzymatic hydrolysis was carried out at a temperature of 50°C and a pH of 6.5 for 60 minutes;

[0030] (7) Homogenize the enzymatically hydrolyzed slurry twice at a pressure of 30 MPa;

[0031] (8) adding 0.3% xanthan gum and 2.5% xylitol to the homogenized slurry;

[0032] (9) Sterilize at 121°C and 103 kPa for 1 min to obtain a high-dietary fiber brown millet slurry product.

[0033] Example 2

[0034] This embodiment provides a high dietary fiber brown millet slurry, the preparation method of which comprises the following steps:

[0035] (1) Whole grain brown millet and wheat bran treated with microwave enzyme inactivation (800W, 2min) were selected as raw materials;

[0036] (2) The rough millet was crushed and passed through an 80-mesh sieve, and then mixed with millet flour, wheat bran, and water in a mass ratio of 4:1:35 and stirred evenly;

[0037] (3) The mixture was gelatinized at 90°C for 10 min;

[0038] (4) After gelatinization, 0.04% of the mass of the mixed solution was added with α-amylase, and the mixture was liquefied at a temperature of 60°C and a pH of 6.0 for 60 minutes;

[0039] (5) After liquefaction, glucoamylase was added at a mass ratio of 0.12% of the mass of the mixed solution, and saccharification was carried out at a temperature of 55° C. and a pH of 6.0 for 50 min;

[0040] (6) After saccharification, 0.10% of the mass of the mixed solution was added with papain, and enzymatic hydrolysis was carried out at 50°C and pH 6.5 for 1 h;

[0041] (7) homogenizing the enzymatically hydrolyzed slurry once at a pressure of 50 MPa;

[0042] (8) adding 0.25% xanthan gum and 1.5% xylitol to the homogenized slurry;

[0043] (9) Sterilize at a temperature of 121°C and a pressure of 103 kPa for 1 min to obtain a high-dietary fiber brown millet slurry product.

[0044] Example 3

[0045] This embodiment provides a high dietary fiber brown millet slurry, the preparation method of which comprises the following steps:

[0046] (1) Whole grain brown millet and wheat bran treated with microwave enzyme inactivation (800W, 2min) were selected as raw materials;

[0047] (2) After the rough millet is crushed, it is passed through an 80-mesh sieve, and the millet flour, wheat bran, and water are mixed in a mass ratio of 4:1.2:40, and stirred evenly;

[0048] (3) The mixture was gelatinized at 85°C for 12 min;

[0049] (4) After gelatinization, 0.04% of the mass of the mixed solution was added with α-amylase, and the mixture was liquefied at a temperature of 50°C and a pH of 6.0 for 55 minutes;

[0050] (5) After liquefaction, glucoamylase was added at a mass ratio of 0.12% of the mass of the mixed solution, and saccharification was carried out at a temperature of 55° C. and a pH of 5.5 for 55 min;

[0051] (6) After saccharification, 0.07% of the mass of the mixed solution was added with papain, and enzymatic hydrolysis was carried out at a temperature of 50°C and a pH of 6.0 for 1.5 h;

[0052] (7) homogenizing the enzymatically hydrolyzed slurry once at a pressure of 50 MPa;

[0053] (8) adding 0.2% xanthan gum and 2.5% xylitol to the homogenized slurry;

[0054] (9) Sterilize at a temperature of 121°C and a pressure of 103 kPa for 1 min to obtain a high-dietary fiber brown millet slurry product.

[0055] Comparative Example 1

[0056] This comparative example provides a high-dietary fiber brown millet slurry. The preparation method thereof differs from that of Example 1 only in step (2): the brown millet is crushed and passed through an 80-mesh sieve, and millet flour, wheat bran and water are mixed in a mass ratio of 4.5:0.5:4.5, and stirred evenly.

[0057] Comparative Example 2

[0058] This comparative example provides a high-dietary fiber brown millet slurry, and the preparation method thereof comprises the following steps:

[0059] (1) Whole grain brown millet and wheat bran treated with microwave enzyme inactivation (800W, 2min) were selected as raw materials;

[0060] (2) The rough millet was crushed and passed through an 80-mesh sieve, and then mixed with millet flour, wheat bran, and water in a mass ratio of 4:1:40 and stirred evenly;

[0061] (3) The mixture was gelatinized at 90°C for 8 min;

[0062] (4) After gelatinization, 0.04% of the mass of the mixed solution was added with α-amylase and 0.12% of glucoamylase, and saccharification and liquefaction were carried out at a temperature of 55°C and a pH of 6.0 for 55 minutes;

[0063] (5) After saccharification, 0.05% of the mass of the mixed solution was added with papain, and enzymatic hydrolysis was carried out at 50°C and pH 6.5 for 1 h;

[0064] (6) homogenizing the enzymatically hydrolyzed slurry once at a pressure of 30 MPa;

[0065] (7) adding 0.2% xanthan gum and 2.5% xylitol to the homogenized slurry;

[0066] (8) Sterilize at a temperature of 121°C and a pressure of 103 kPa for 1 min to obtain a high-dietary fiber brown millet slurry product.

[0067] Comparative Example 3

[0068] This comparative example provides a high-dietary fiber brown millet slurry, and the preparation method thereof comprises the following steps:

[0069] (1) Select whole grains brown millet and quinoa as raw materials;

[0070] (2) to (9) are the same as in Example 1.

[0071] Test Example 1

[0072] The nutritional components of the millet slurries prepared in Examples 1-3 and Comparative Examples 1-3 were tested, and the test results are shown in Table 1 below.

[0073] The detection method is as follows:

[0074] Total solids content QB / T 4221-2011 Cereal beverages;

[0075] Crude protein GB 5009.5-2025 National Food Safety Standard Determination of Protein in Foods;

[0076] Crude fat GB 5009.6-2016 National Food Safety Standard Determination of Fat in Foods;

[0077] Dietary fiber GB 5009.88-2023 National Food Safety Standard Determination of dietary fiber in foods;

[0078] Vitamin B1 GB 5009.84-2016 National Food Safety Standard Determination of Vitamin B1 in Foods;

[0079] Vitamin B2 GB 5009.84-2016 National Food Safety Standard Determination of Vitamin B2 in Foods.

[0080] Table 1

[0081]

[0082] The results showed that the total solids and total dietary fiber content of the millet concentrate provided by the present invention met the requirements for total solids and total dietary fiber content of cereal concentrates in China's light industry standard QB / T 4221-2011, "Cereal Beverages." Furthermore, the product's total dietary fiber content was ≥3g / 420kJ, meeting the requirements for product claims of "high or rich in dietary fiber or a good source" in GB 28050-2025, "National Food Safety Standard, General Rules for Nutrition Labeling of Prepackaged Foods."

[0083] Test Example 2

[0084] The sensory quality of the millet syrups prepared in Examples 1-3 and Comparative Examples 1-3 was evaluated. The scoring criteria are shown in Table 2 (total score 100 points), and the evaluation results are shown in Table 3.

[0085] Table 2

[0086]

[0087] Table 3

[0088]

[0089]

[0090] The results show that the high dietary fiber brown millet pulp provided by the embodiment of the present invention has good uniformity, texture and taste, a high comprehensive score, and good sensory quality.

[0091] Test Example 3

[0092] The millet slurries prepared in Examples 1-3 and Comparative Example 1 were stored at room temperature for 10 days and subjected to sensory evaluation according to the standards in Table 2. The results are shown in Table 4 below.

[0093] Table 4

[0094]

[0095] The results showed that the millet concentrates of Examples 1-3 did not show any water separation, precipitation, stratification or weak gelation before and after storage, and the quality did not change significantly, indicating that the millet concentrate provided by the present invention has excellent storage stability.

[0096] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made thereto. Therefore, such modifications and improvements, without departing from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A method for preparing a high-dietary fiber brown millet slurry, characterized in that: The method comprises: taking whole grain brown millet, wheat bran and water as raw materials, and sequentially performing mixing, gelatinization, liquefaction, saccharification, enzymolysis, homogenization, adding additives and sterilization to obtain the high dietary fiber brown millet slurry.

2. The method for preparing the high dietary fiber brown millet slurry according to claim 1, wherein: The wheat bran is enzyme-inactivated wheat bran, and the enzyme-inactivating conditions are: microwave 700-900W, 1-2min; The mass ratio of the whole grain brown millet, wheat bran and water is 4:1-1.5:35-40.

3. The method for preparing the high dietary fiber brown millet slurry according to claim 1, wherein: The gelatinization conditions are: stirring at a temperature of 85-95° C. for 8-12 minutes.

4. The method for preparing the high dietary fiber brown millet slurry according to claim 1, wherein: The liquefaction comprises: adding 0.035-0.045% by mass of α-amylase to the gelatinized mixture, and stirring for 50-60 minutes under the conditions of a temperature of 50-60° C. and a pH of 5.0-7.

0.

5. The method for preparing the high dietary fiber brown millet slurry according to claim 1, wherein: The saccharification comprises: adding 0.10-0.12% by mass of glucoamylase to the liquefied mixture, and stirring for 50-60 minutes at a temperature of 55-60° C. and a pH of 3.5-6.

0.

6. The method for preparing the high dietary fiber brown millet slurry according to claim 1, wherein: The enzymatic hydrolysis comprises: adding 0.05-0.10% by mass of papain to the saccharified mixture, and stirring for 1-4 hours at a temperature of 45-55° C. and a pH of 5.0-11.

0.

7. The method for preparing the high dietary fiber brown millet slurry according to claim 1, wherein: The homogenization conditions are: homogenization 1-2 times at a pressure of 30-50 MPa.

8. The method for preparing the high dietary fiber brown millet slurry according to claim 1, wherein: The additives include xanthan gum and xylitol; the added amount of the xanthan gum is 0.2-0.3%, and the added amount of the xylitol is 0.5-2.5%.

9. The method for preparing the high dietary fiber brown millet slurry according to claim 1, wherein: The sterilization conditions are: temperature 121° C., pressure 103 kPa, sterilization for 1-10 minutes.

10. A high dietary fiber brown millet slurry, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 9.

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