A burdock solid beverage rich in type I difructose anhydride, inulin and oligofructose

Abstract

The invention discloses a burdock solid beverage rich in type I difructose anhydride, inulin and oligofructose, and belongs to the technical field of food processing. The present invention adopts natural medicinal and edible herb burdock, and the prepared burdock solid beverage has diversified functional elements by enzymatic hydrolysis of burdock root, including inulin contained in itself, generated oligofructose (GF2, GF3, GF4) and potential functional sweetener DFA-I, wherein the contents of inulin, GF2, GF3, GF4 and DFA-I are 13.2%, 1.5%, 1.6%, 1.6% and 4.6% respectively. The burdock solid beverage prepared by the present invention contains a variety of prebiotics; at the same time, the burdock solid beverage provided by the present invention is packaged into a small bag volume, easy to carry and brew, and is a solid beverage product for convenient nutrition and health, and is a deep processing and utilization form of burdock, with broad market prospects.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to a burdock solid beverage rich in type I disulphose anhydride, inulin and oligofructose. Background Art

[0002] Burdock is a plant of the Asteraceae family and is a herbaceous plant that can be used as both medicine and food. The burdock root is the rhizome of the burdock. It is thick and conical in shape. It has rich nutritional value and mainly contains amino acids, polyphenols, burdock acid, volatile oil, dietary fiber, and oligosaccharides. The inulin content accounts for about 30% of the dry weight of the burdock root. It is a soluble dietary fiber that is not digested in the body and helps to lower blood lipids and promote the reproduction of intestinal probiotics. Studies have shown that burdock has medicinal value such as dispersing wind-heat, benefiting the lungs and clearing rashes, dispersing knots and detoxifying; it has the effects of lowering blood sugar, blood pressure, blood lipids, and improving human immunity, and can be used as an auxiliary treatment for diabetes, hypertension, hyperlipidemia and other diseases.

[0003] Inulin (inulin) can be converted into a potential functional sweetener, type I difructose anhydride, under the action of type I inulin fructotransferase. Type I difructose anhydride DFA-I has only half the sweetness of sucrose and can be used as a potential new low-calorie sweetener. At the same time, some byproducts of inulin conversion by type I inulin fructotransferase are oligofructose. Oligofructose is a food additive and a prebiotic that can promote the growth of intestinal probiotics and the absorption of mineral elements such as Ca, Mg and Fe. It is widely used in the food industry.

[0004] In order to adapt to the accelerated pace of life, people's consumption of convenient, healthy and nutritious solid beverage products has increased. However, most of the products developed for burdock on the market are burdock tea and burdock sauce, and there are few deep-processed products. Due to the high fiber content of burdock and the easy aging due to improper storage, the quality of burdock food is easy to deteriorate during processing and storage and transportation. At the same time, burdock is rich in inulin, which is a widely used dietary fiber and also a prebiotic. However, at present, there is only a simple extraction process study on inulin in burdock, and there is no research on the deep processing of burdock inulin. In order to realize the deep processing of burdock inulin and increase the functionality and nutritional value of burdock, burdock can be directly processed by enzymatic method without extracting inulin from burdock first, eliminating the extraction cost and increasing the added value of burdock. The high content of inulin in burdock has not been developed and utilized to a small extent. Therefore, how to achieve deep processing of burdock through enzymatic methods to improve the added value and nutritional value of burdock is a technical problem that needs to be solved at present.

[0005] The essence of spray drying is to remove the water in the non-volatile slurry by vaporization to obtain powdered granular substances. This method can complete the drying process instantly and the product quality is stable. Therefore, spray drying has become a common method for drying liquid products into powdered products. At the same time, due to the high temperature in spray drying, the inulin fructotransferase type I can be inactivated. Summary of the invention

[0006] The object of the present invention is to provide a method for preparing a burdock solid beverage rich in type I difructose anhydride (DFA-I), inulin and oligofructose, so as to solve the problems raised in the above background technology.

[0007] The first object of the present invention is to provide a method for preparing a burdock solid beverage rich in type I difructose anhydride, inulin and oligofructose, comprising the following steps:

[0008] (1) preparing burdock root slices from fresh burdock root;

[0009] (2) drying and baking the burdock root slices obtained in step (1), and then crushing them after cooling to prepare burdock root powder;

[0010] (3) adding an appropriate amount of water to the burdock root powder obtained in step (2) to prepare a slurry, and heating and stirring to obtain a burdock extract;

[0011] (4) cooling the burdock extract in step (3), adding type I inulin fructotransferase derived from the microorganism Microbacterium flavum DSM 18909 for enzymatic hydrolysis, and obtaining a burdock reaction solution;

[0012] (5) Drying the burdock reaction solution obtained in step (4) to prepare a burdock solid beverage.

[0013] In one embodiment, in step (1), the selected burdock root is required to be fresh and free from insect infestation and rot; the thickness of the burdock root slices is 3 to 4 mm.

[0014] In one embodiment, in step (2), the drying temperature is 60-80° C., and the baking condition is 120-150° C. until the burdock root slices are white in the middle and brown at the edges; the burdock root is crushed to 100-200 mesh.

[0015] In one embodiment, in step (3), water in an amount of 10-15 times the mass of the burdock root powder is added to the burdock root powder for slurry preparation.

[0016] In one embodiment, in step (3), the heating and stirring conditions are leaching at 75-90° C. and a stirring speed of 300 rpm for 1-3 hours.

[0017] In one embodiment, in step (4), the burdock extract is cooled to 50-55° C. before enzymatic hydrolysis.

[0018] In one embodiment, in step (4), the amount of the type I inulin fructotransferase added is 1:1% of the mass of burdock root.

[0019] In one embodiment, the amino acid sequence of the type I inulin fructotransferase is shown as SEQ ID NO.2.

[0020] In one embodiment, the nucleotide sequence of the type I inulin fructotransferase is shown as SEQ ID NO.1.

[0021] In one embodiment, the specific activity of the type I inulin fructotransferase enzyme preparation is 351 U / mg.

[0022] In one embodiment, in step (4), the enzymatic hydrolysis time is 0.5 to 2 hours.

[0023] In one embodiment, in step (5), the burdock reaction solution is directly spray-dried to prepare a burdock solid beverage.

[0024] The invention provides a burdock solid beverage prepared by the method.

[0025] The present invention provides application of the method or the burdock solid beverage in the field of food.

[0026] The invention provides application of the type I inulin fructotransferase in preparing a burdock solid beverage rich in type I difructose anhydride, inulin and oligofructose, wherein the type I inulin fructotransferase is derived from the microorganism Microbacterium flavum DSM18909.

[0027] In one embodiment, the amino acid sequence of the type I inulin fructotransferase is shown as SEQ ID NO.2.

[0028] In one embodiment, the nucleotide sequence of the type I inulin fructotransferase is shown as SEQ ID NO.1.

[0029] The invention provides application of the type-I inulin fructotransferase in preparing type-I difructose anhydride or a product containing the type-I difructose anhydride; the type-I inulin fructotransferase is derived from the microorganism Microbacterium flavum DSM18909.

[0030] In one embodiment, the application uses burdock, inulin or other edible plants rich in inulin as substrate.

[0031] In one embodiment, the amino acid sequence of the type I inulin fructotransferase is shown as SEQ ID NO.2.

[0032] In one embodiment, the nucleotide sequence of the type I inulin fructotransferase is shown as SEQ ID NO.1.

[0033] In one embodiment, the product comprises a food or a pharmaceutical.

[0034] In one embodiment, the food comprises a health product, a functional food or a special food.

[0035] The invention provides application of the type I inulin fructotransferase in the field of food. The inulin fructotransferase is derived from the microorganism Microbacterium flavum DSM 18909.

[0036] In one embodiment, the amino acid sequence of the type I inulin fructotransferase is shown as SEQ ID NO.2.

[0037] In one embodiment, the nucleotide sequence of the type I inulin fructotransferase is shown as SEQ ID NO.1.

[0038] In summary, the beneficial technical effects of the present invention are:

[0039] 1. The burdock, a natural herbaceous plant with both medicinal and edible properties, is used in the present invention. The functionality of the burdock root is improved by processing the burdock root, thereby making full use of the burdock resources.

[0040] 2. The burdock solid beverage prepared by the present invention has diversified functional elements, including inulin contained in the burdock solid beverage, oligofructose (GF 2 GF 3 GF 4 ) and potential functional sweetener type I difructose anhydride DFA-I, among which inulin, GF 2 GF 3 GF 4 The contents of difructose anhydride type I (DFA-I) are 13.2%, 1.5%, 1.6%, 1.6% and 4.6% respectively, which can promote the absorption of minerals, resist tooth decay, improve constipation, promote the reproduction of probiotics, inhibit cholesterol absorption, and enhance human immunity and resistance, thus improving the quality of burdock solid beverage.

[0041] 3. The product of the present invention is solid particles and is packaged in bags with small volume, easy to carry and brew, and is a convenient, nutritious and healthy solid beverage product. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1HPLC charts of standard fructose, glucose and sucrose;

[0043] Figure 2 Standard oligofructose GF 2 GF 3 and GF 4 HPLC chart of

[0044] Figure 3 This is the HPLC chart of the standard type I difructose anhydride DFA-I;

[0045] Figure 4 This is the HPLC detection and analysis of the components after the burdock root powder enzyme reaction in Example 3. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical methods and advantages of the present invention clearer, the technical scheme of the present invention will be further described in detail below in conjunction with the accompanying drawings. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0047] Example 1 Preparation of an enzyme preparation having type I inulin fructotransferase activity

[0048] (1) Plasmid construction: The gene of type I inulin fructotransferase from Microbacterium flavum DSM 18909 (nucleotide sequence as shown in SEQ ID NO.1) was constructed into the multiple cloning site of pET-22b(+) plasmid by gene synthesis to obtain the recombinant plasmid pET-22b(+)-MfIFTase-I.

[0049] (2) Transformation and induced expression of recombinant plasmid: The recombinant plasmid pET-22b(+)-MfIFTase-I constructed in step (1) was transformed into E. coli BL21(DE3) competent cells, spread on LB plates and cultured inverted overnight, single colony clones were selected and cultured in LB liquid medium at 37°C and 200 rpm overnight, and then transferred into LB liquid medium at an inoculum of 2% (v / v) and cultured at 37°C until OD 600 The value was 0.6, IPTG was added with a final concentration of 0.5 mM, and the mixture was induced at 28 °C and 200 rpm for 72 h, and the fermentation broth was collected.

[0050] (3) Isolation and purification of type I inulin fructosyltransferase: The fermentation broth was centrifuged at 4°C and 10,000 rpm for 30 min to obtain the bacterial precipitate. 20 mL of buffer (50 mM PBS, 500 mM NaCl, pH adjusted to 5.5) was added to the bacterial precipitate to fully resuspend the bacterial cells, and then placed in an ultrasonic cell disruptor for ultrasonic disruption to obtain a crude enzyme solution, which was filtered with a 0.22 μm microporous filter for later use. The protein was purified using a nickel ion affinity chromatography column to obtain the target protein. The purified inulin fructosyltransferase reached electrophoretic purity.

[0051] (4) Determination of type I inulin fructotransferase activity: Dissolve in 10 mmol L -1 A certain amount of the type I inulin glycosyltransferase purified in step (3) was added to a 1% (W / V) inulin (inulin) solution in acetate buffer (pH 5.5), reacted at 50°C for 10 min, and inactivated by boiling water bath for 10 min. After boiling water bath, the reaction solution was heated at 10000 r min -1 The supernatant was filtered through a 0.22 μm microporous membrane and the type I difructose anhydride DFA-I was determined using a Sugar-Pak I calcium cation exchange column to calculate the type I inulin fructotransferase activity.

[0052] The unit enzyme activity is defined as: the amount of enzyme required to generate 1 μmol of type I difructose anhydride DFA-I per minute under the optimal reaction conditions (pH 5.5, 50°C) is 1 U.

[0053] The enzyme activity of the type I inulin glycosyltransferase prepared in Example 1 is 351 U / mg, the optimum temperature is 50° C., and the optimum pH is 5.5.

[0054] Example 2 Preparation of burdock solid beverage

[0055] (1) Preparation of burdock root powder: Select fresh burdock root, wash it with clean water for 5 to 6 times, peel it and cut it into thin slices using a stainless steel slicer for later use; dry the burdock root slices at 60 to 80° C., and bake them in a baking oven at 130° C. for 2 h until the burdock root slices are white in the middle and brown at the edges, and then grind them into 100 to 200 meshes after cooling;

[0056] (2) Preparation of burdock extract: Add 10 times the weight of pure water to burdock root powder to prepare a slurry, and heat and stir at 75° C. for 3 h;

[0057] (3) Preparation of burdock reaction solution: The burdock extract was cooled to 50-55°C, and the type I inulin fructotransferase enzyme preparation prepared in Example 1 (weight of burdock root) was added. ), enzymolysis for 1 h to obtain burdock reaction solution;

[0058] (4) Preparation of burdock solid beverage: The burdock reaction solution is directly spray-dried to prepare burdock powder, which is quantitatively packaged using a dedicated packaging device, with each bag containing 10±0.5 g.

[0059] Example 3 Preparation of burdock solid beverage

[0060] (1) Preparation of burdock root powder: Select fresh burdock root, wash it with clean water for 5 to 6 times, peel it and cut it into thin slices using a stainless steel slicer for later use; dry the burdock root slices at 60 to 80° C., and bake them in a baking oven at 130° C. for 2 h until the burdock root slices are white in the middle and brown at the edges, and then grind them into 100 to 200 meshes after cooling;

[0061] (2) Preparation of burdock extract: Add 12 times the weight of water to burdock root powder to prepare a slurry, and heat and stir at 80°C for 2 h;

[0062] (3) Preparation of burdock reaction solution: The burdock extract was cooled to 50-55°C, and the type I inulin fructotransferase enzyme preparation prepared in Example 1 (weight of burdock root) was added. ), enzymolysis for 2 h to obtain burdock reaction solution;

[0063] (4) Preparation of burdock solid beverage: The burdock reaction solution is directly spray-dried to prepare burdock powder, which is quantitatively packaged using a dedicated packaging device, with each bag containing 10±0.5 g.

[0064] Example 4 Preparation of burdock solid beverage

[0065] (1) Preparation of burdock root powder: Select fresh burdock root, wash it with clean water for 5 to 6 times, peel it and cut it into thin slices using a stainless steel slicer for later use; dry the burdock root slices at 60 to 80° C., and bake them in a baking oven at 130° C. for 2 h until the burdock root slices are white in the middle and brown at the edges, and then grind them into 100 to 200 meshes after cooling;

[0066] (2) Preparation of burdock extract: Add 15 times the weight of water to burdock root powder to prepare a slurry, and heat and stir at 90° C. for 1 h;

[0067] (3) Preparation of burdock reaction liquid: The burdock extract was cooled to 50-55° C., and the type I inulin fructotransferase enzyme preparation prepared in Example 1 (0.1‰ of the mass of burdock root) was added, and enzymolysis was performed for 0.5 h to obtain a burdock reaction liquid;

[0068] (4) Preparation of burdock solid beverage: The burdock reaction solution is directly spray-dried to prepare burdock powder, which is quantitatively packaged using a dedicated packaging device, with each bag containing 10±0.5 g.

[0069] Example 5 Quality Inspection of Burdock Solid Beverage

[0070] The burdock solid beverage prepared without adding type I inulin fructotransferase enzyme preparation was used as the control group, and the contents of inulin, oligofructose and type I difructose anhydride DFA-I in the burdock solid beverage prepared in Example 3 were detected.

[0071] 1. Experimental methods

[0072] The prepared burdock solid beverage was dissolved in ultrapure water and filtered through a 0.22 μm microporous filter membrane for later use. Inulin was determined by the phenol-sulfuric acid method and the DNS method, and oligofructose and type I difructose anhydride DFA-I were determined by HPLC. The product identification and content detection were performed using an Asahipak NH2P-50 4E amino column, with a mobile phase of 70% acetonitrile and a flow rate of 1 mL min -1 , column temperature was 30°C, sample volume was 10 μL, and the detector was a Shodex differential refractometer.

[0073] 2. Experimental results

[0074] As shown in Table 1, compared with the control group, the oligofructose content in the burdock solid beverage powder obtained in Example 3 increased, and a large amount of potential functional sweetener DFA-I was generated, reaching 4.6g / 100g. In addition, except for the decrease in mass of inulin in Table 1, which is greater than the sum of the mass increase of other sugars, it indicates that other types of oligofructose may also be generated in the reaction. These types of sugars can play a synergistic role, improve sugar and lipid metabolism, promote the absorption of minerals, resist dental caries, regulate the balance of intestinal flora and enhance human immunity ( Figure 1-Figure 4 ).

[0075] Table 1 Sugar content of burdock solid beverage obtained in Example 3

[0076]

[0077] 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 a burdock solid beverage rich in type I difructose anhydride, inulin and oligofructose, characterized in that: The steps include: (1) preparing burdock root slices; (2) Slicing the burdock root, drying and baking it, and then crushing it after cooling to prepare burdock root powder; (3) adding an appropriate amount of water to the burdock root powder to prepare a slurry, and heating and stirring to obtain a burdock extract; (4) Cool the burdock extract and add Microbacterium flavum The burdock reaction solution was obtained by enzymolysis with type I inulin fructosyltransferase of DSM18909; the nucleotide sequence of the type I inulin fructosyltransferase is shown in SEQ ID NO.1; (5) The burdock reaction liquid is dried to prepare a burdock solid beverage.

2. The method according to claim 1, characterized in that In step (1), the selected burdock root is a fresh burdock root; the thickness of the burdock root slices is 3-4 mm.

3. The method according to claim 1, characterized in that In step (2), the drying temperature is 60-80° C., and the baking condition is 120-150° C. until the burdock root slices are white in the middle and brown at the edges; and the burdock root slices are crushed to 100-200 mesh.

4. The method according to claim 1, characterized in that In step (3), water in an amount of 10 to 15 times the mass of the burdock root powder is added to prepare a slurry; the heating and stirring conditions are: immersion at 75 to 90° C. and a stirring speed of 300 rpm for 1 to 3 h.

5. The method according to claim 1, characterized in that In step (4), the burdock extract is cooled to 50-55°C before enzymolysis, and the enzymolysis time is 0.5-2 h; the amount of the type I inulin fructotransferase added is 0.06‱-0.1‰ of the mass of the burdock root.

6. A burdock solid beverage prepared by the method described in any one of claims 1 to 5.

7. Use of type I inulin fructotransferase in the preparation of type I difructose anhydride or burdock products containing type I difructose anhydride, wherein the type I inulin fructotransferase is derived from a microorganism Microbacterium flavum DSM 18909; the nucleotide sequence of the type I inulin fructotransferase is shown in SEQ ID NO.

1.

8. The use according to claim 7, characterized in that: The product includes a food or a medicine.

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