Method for preparing high-solubility dendrobium officinale powder based on polysaccharide enzymolysis technology

Abstract

The invention relates to a method for preparing high-solubility dendrobium officinale powder based on a polysaccharide enzymolysis technology, and belongs to the technical field of food processing. The invention relates to a method for preparing high-solubility dendrobium officinale powder based on a polysaccharide enzymolysis technology, which comprises the following steps of: crushing, grinding and sieving dendrobium officinale dry strips to obtain dendrobium officinale dry powder, and adding the dendrobium officinale dry powder into purified water to obtain dendrobium officinale dispersion liquid; heating the dispersion liquid in a water bath at 90-100 DEG C for 1-2 hours, centrifuging, and collecting supernate to obtain an extracting solution; and adding glycosidase into the extracting solution, carrying out enzymolysis at 40-60 DEG C for 1-1.5 hours, and carrying out enzyme deactivation, high-pressure homogenization and spray drying to obtain the high-solubility dendrobium officinale powder. By means of enzymolysis treatment, the yield of the effective component (polysaccharide) in the dendrobium nobile powder is increased. The method is easy to operate, mild in condition and relatively short in production period, other substances cannot be introduced, and adverse effects on the flavor of the prepared high-solubility dendrobium officinale powder cannot be caused.

Description

TECHNICAL FIELD

[0001] The application relates to a method for preparing high-solubility dendrobium officinale powder based on enzymatic polysaccharide technology, and belongs to the technical field of food processing. BACKGROUND

[0004] Powder dosage form products are suitable for consumers' own lifestyles, have the advantages of convenient carrying, easy to take and delicious, etc. However, the main effective substance in dendrobium officinale, polysaccharide, greatly affects its application in the food field due to its poor molecular weight and solubility. At present, the enzyme hydrolysis technology is often used in the food field because of its mild action condition, safety, easy control and remarkable effect. A large number of studies have shown that enzyme hydrolysis can improve some functional properties of polysaccharide. The glycosidic bond of polysaccharide can be destroyed by glycosidase hydrolysis, the amount of smaller and more hydrophilic polysaccharide can be increased, and the exposed electrostatic charge density can be improved, so that the functional properties can be changed. Although this technology has been widely used in the treatment of animal glycosides and plant glycosides, there are few reports on increasing the solubility of polysaccharide by enzyme hydrolysis.

[0005] At present, the low-speed solubility and low solubility of dendrobium officinale powder are the main reasons for limiting its wide application in the food industry. With the reduction of the cost of glycosidase, it has important practical significance to improve the solubility of dendrobium officinale powder by using green and healthy enzyme hydrolysis modification technology. Patent CN107243051A discloses a preparation method of Huoshan dendrobium pure powder tablets, which is obtained by processing Huoshan dendrobium through cleaning, sterilization, crushing, centrifugation, drying, tabletting and packaging. The prepared product has the advantages of simple preparation process, convenient use, no auxiliary materials, high purity, stable quality, high utilization, safety and effectiveness. Although the method has strong operability, it does not improve the solubility of the product, and has certain limitations for fully exerting the nutritional effect of dendrobium officinale. Patent CN108936526A discloses a Huoshan dendrobium seasoning powder for health care and a preparation method thereof. The seasoning powder with health care function is obtained by mixing Huoshan dendrobium, licorice, polygonatum, mulberry leaves, rosemary, L-alanine and volvariella volvacea in a certain proportion. However, such a compound design aims to maximize the synergistic effect, but it faces multiple challenges: in the physical and chemical aspects, there is a risk of chemical antagonism between components and mutual interference of bioavailability, which may lead to failure or even weakening of the expected effect; in the sensory aspect, the coexistence of multiple strong taste active substances easily causes flavor interaction deterioration, which seriously affects the palatability of the product and the long-term compliance of users. SUMMARY

[0006] To address the poor solubility and other technical problems of Dendrobium officinale powder in existing technologies, this invention provides a method for preparing highly soluble Dendrobium officinale powder based on enzymatic hydrolysis of polysaccharides. This invention utilizes glycosidases to hydrolyze polysaccharides in Dendrobium officinale dispersions to obtain highly soluble Dendrobium officinale powder. Simultaneously, the effects of the type and ratio of glycosidases on the physicochemical properties of Dendrobium officinale powder were investigated, providing experimental data and a theoretical basis for Dendrobium officinale powder production practices.

[0007] A method for preparing highly soluble Dendrobium officinale powder based on enzymatic hydrolysis of polysaccharides involves adding the dried Dendrobium officinale powder obtained by crushing, grinding, and sieving dried Dendrobium officinale strips to pure water to obtain a Dendrobium officinale dispersion; heating the dispersion in a water bath at 90-100℃ for 1-2 h, centrifuging, collecting the supernatant to obtain an extract; adding glycosidase to the extract, enzymatically hydrolyzing at 40-60℃ for 1-1.5 h, inactivating the enzyme, homogenizing under high pressure, and spray drying to obtain highly soluble Dendrobium officinale powder.

[0008] In the above technical solution, the mass ratio of the dried Dendrobium officinale powder to purified water is 1:5~10.

[0009] In the above technical solution, the centrifugation speed is 3000~5000 rpm and the time is 10~15 min.

[0010] Preferably, the centrifugation speed is 4000 rpm and the time is 10 min.

[0011] In the above technical solution, the mass ratio of the dried Dendrobium officinale powder to purified water is 1:5~10.

[0012] In the above technical solution, the glycosidase is one or more of cellulase, pectinase, glucanase or mannanase.

[0013] In the method described in this invention, when the glycosidase is a combination of multiple enzymes, the enzymes can be mixed in any proportion.

[0014] Preferably, the glycosidase is a combination of glucanase and mannanase.

[0015] More preferably, the activity of the dextranase is 40,000 u / g, and the activity of the mannanase is 50,000 u / g.

[0016] More preferably, the mass ratio of the dextranase to the mannanase is 0.8~1.2:1.

[0017] In the above technical solution, the amount of glycosidase added is 0.5‰~1‰ of the total mass of Dendrobium officinale dispersion.

[0018] In the above technical solution, the dried Dendrobium officinale strips obtained by drying or freeze-drying are crushed and ground by a grinder and passed through a 100-mesh sieve to obtain Dendrobium officinale powder.

[0019] In the above technical solution, the enzymatically hydrolyzed Dendrobium officinale dispersion is heated to 90~100℃ and kept for 5~8 minutes to inactivate the enzyme.

[0020] In the above technical solution, the high-pressure homogenization pressure is 100~200 MPa, and the time is 10~15 min.

[0021] In the above technical solution, the spray drying conditions are: inlet temperature 130~150℃, outlet temperature 80~90℃, fan frequency 50~60 Hz, and feed flow rate 8~10 mL / min.

[0022] Preferably, the optimal conditions for spray drying are: inlet temperature 130°C, outlet temperature 90°C, fan frequency 55Hz, and feed flow rate 10mL / min.

[0023] Another object of the present invention is to provide highly soluble Dendrobium officinale powder prepared by the above method.

[0024] The beneficial effects of this invention are: 1. This invention utilizes enzymatic hydrolysis to increase the yield of polysaccharides, the active ingredient in Dendrobium officinale powder. This method is simple to operate, operates under mild conditions, has a relatively short production cycle, and does not introduce other substances, thus avoiding any adverse effects on the flavor of the prepared highly soluble Dendrobium officinale powder.

[0025] 2. This invention employs a multi-enzyme complex enzymatic hydrolysis technology, selecting two glycosidases to enzymatically hydrolyze the polysaccharides of Dendrobium officinale. Utilizing the dual enzymatic catalytic effect, the catalytic activity is enhanced, and the catalytic effect is strengthened, successfully decomposing the polysaccharides in Dendrobium officinale into smaller molecules. The solubility increases from 8%–10% before enzymatic hydrolysis to 80%–90%. This method not only significantly improves the solubility of Dendrobium officinale powder, but the reduced molecular weight also makes it more conducive to the absorption and utilization of active ingredients by the human body. Attached Figure Description

[0026] Figure 1 This is a schematic flowchart of the method for preparing highly soluble Dendrobium officinale powder based on enzymatic hydrolysis technology according to the present invention. Detailed Implementation

[0027] The following non-limiting embodiments are intended to enable those skilled in the art to more fully understand the invention, but do not limit the invention in any way.

[0028] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; the reagents and materials described are commercially available unless otherwise specified.

[0029] Example 1 A method for preparing highly soluble Dendrobium officinale powder includes the following steps: Step 1: Dry Dendrobium officinale to obtain dried Dendrobium officinale strips, then grind them using a grinder, and pass them through a 100-mesh sieve to obtain Dendrobium officinale powder; pour 5 kg of Dendrobium officinale powder into a small fermentation tank, and while stirring, add 30 L of purified water, then stir evenly to prepare Dendrobium officinale powder dispersion; heat the dispersion in a water bath at 95℃ for 2 hours, centrifuge at 4000 rpm for 10 minutes, and collect the supernatant to obtain the extract; Step 2: Add 19 g of dextranase with an enzyme activity of 40,000 u / g and 16 g of mannanase with an enzyme activity of 50,000 u / g to the Dendrobium officinale extract. Then, heat the above solution to 50°C for enzymatic hydrolysis for 1 h. After the enzymatic hydrolysis reaction is completed, heat it to 100°C and hold for 5 min to inactivate the enzyme, and obtain the enzymatic hydrolysate. Step 3: Homogenize the enzyme hydrolysate under high pressure at 100 MPa for 10 min; Step 4: The homogenized enzymatic hydrolysate is spray-dried with an inlet air temperature of 135℃, an outlet air temperature of 68℃, a fan frequency of 50 Hz, and a feed flow rate of 10 mL / min to obtain highly soluble Dendrobium officinale powder.

[0030] Example 2 Step 1: Dry Dendrobium officinale to obtain dried Dendrobium officinale strips, then grind them using a grinder, and pass them through a 100-mesh sieve to obtain Dendrobium officinale powder; pour 5 kg of Dendrobium officinale powder into a small fermentation tank, and while stirring, add 25 L of purified water, then stir evenly to prepare Dendrobium officinale powder dispersion; heat the dispersion in a water bath at 95℃ for 1.5 h, centrifuge at 3500 rpm for 10 min, and collect the supernatant to obtain the extract; Step 2: Add 8 g of glucanase with an enzyme activity of 40,000 u / g and 7 g of mannanase with an enzyme activity of 50,000 u / g to the Dendrobium officinale extract. Then, heat the above solution to 50°C for enzymatic hydrolysis for 1 h. After the enzymatic hydrolysis reaction is completed, heat it to 100°C and hold for 5 min to inactivate the enzyme, and obtain the enzymatic hydrolysate. Step 3: Homogenize the enzyme hydrolysate under high pressure at 100 MPa for 10 min; Step 4: The homogenized enzymatic hydrolysate is spray-dried with an inlet air temperature of 135℃, an outlet air temperature of 68℃, a fan frequency of 55 Hz, and a feed flow rate of 8 mL / min to obtain highly soluble Dendrobium officinale powder.

[0031] Example 3 Step 1: Dry Dendrobium officinale to obtain dried Dendrobium officinale strips, then grind them using a grinder, and pass them through a 100-mesh sieve to obtain Dendrobium officinale powder; pour 5 kg of Dendrobium officinale powder into a small fermentation tank, and while stirring, pour in 50 L of purified water, then stir evenly to prepare Dendrobium officinale powder dispersion; place the dispersion in a water bath at 90℃ for 1 hour, centrifuge at 3000 rpm for 10 minutes, and collect the supernatant to obtain the extract; Step 2: Add 30 g of glucanase with an enzyme activity of 40,000 u / g and 25 g of mannanase with an enzyme activity of 50,000 u / g to the Dendrobium officinale extract, and then heat it to 60℃ for enzymatic hydrolysis for 1 h; after the enzymatic hydrolysis reaction is completed, heat it to 100℃ and hold for 5 min to inactivate the enzyme, and obtain the enzymatic hydrolysate; Step 3: Homogenize the enzyme hydrolysate under high pressure at 100 MPa for 10 min; Step 4: The homogenized enzymatic hydrolysate is spray-dried under the following conditions: inlet air temperature 135℃, outlet air temperature 68℃, fan frequency 60 Hz, and feed flow rate 9 mL / min, to obtain highly soluble Dendrobium officinale powder.

[0032] Example 4 Step 1: Dry Dendrobium officinale to obtain dried Dendrobium officinale strips, then grind them using a grinder, and pass them through a 100-mesh sieve to obtain Dendrobium officinale powder; pour 5 kg of Dendrobium officinale powder into a small fermentation tank, and while stirring, add 30 L of purified water, then stir evenly to prepare Dendrobium officinale powder dispersion; heat the dispersion in a water bath at 95℃ for 2 hours, centrifuge at 4000 rpm for 10 minutes, and collect the supernatant to obtain the extract; Step 2: Add 35 g of dextranase to the Dendrobium officinale extract, heat the dispersion to 50°C for enzymatic hydrolysis for 1 h; after the enzymatic hydrolysis is completed, heat it to 100°C and hold for 5 min to inactivate the enzyme, and obtain the enzymatic hydrolysate. Step 3: Homogenize the enzyme hydrolysate under high pressure at 100 MPa for 10 min; Step 4: Spray dry the homogenized enzymatic hydrolysate under the following conditions: inlet air temperature 135℃, outlet air temperature 68℃, fan frequency 50 Hz, and feed flow rate 10 mL / min.

[0033] Example 5 Step 1: Dry Dendrobium officinale to obtain dried Dendrobium officinale strips, then grind them using a grinder, and pass them through a 100-mesh sieve to obtain Dendrobium officinale powder; pour 5 kg of Dendrobium officinale powder into a small fermentation tank, and while stirring, add 30 L of purified water, then stir evenly to prepare Dendrobium officinale powder dispersion; heat the dispersion in a water bath at 95℃ for 2 hours, centrifuge at 4000 rpm for 10 minutes, and collect the supernatant to obtain the extract; Step 2: Add 35 g of mannanase to the Dendrobium officinale extract, heat the dispersion to 50°C for enzymatic hydrolysis for 1 h; after the enzymatic hydrolysis is completed, heat it to 100°C and hold for 5 min to inactivate the enzyme, and obtain the enzymatic hydrolysate. Step 3: Homogenize the enzyme hydrolysate under high pressure at 100 MPa for 10 min; Step 4: Spray dry the homogenized enzymatic hydrolysate under the following conditions: inlet air temperature 135℃, outlet air temperature 68℃, fan frequency 55 Hz, and feed flow rate 8 mL / min.

[0034] Comparative Example 1 The difference between this comparative example and Example 1 is that no glycosidase was added for enzymatic hydrolysis. All other operations are the same as in Example 1, specifically including the following steps: Step 1: Dry Dendrobium officinale to obtain dried Dendrobium officinale strips, then grind them using a grinder, and pass them through a 100-mesh sieve to obtain Dendrobium officinale powder; pour 5 kg of Dendrobium officinale powder into a small fermentation tank, and while stirring, add 30 L of purified water, then stir evenly to prepare Dendrobium officinale powder dispersion; heat the dispersion in a water bath at 95℃ for 2 hours, centrifuge at 4000 rpm for 10 minutes, and collect the supernatant to obtain the extract; Step 2: Heat the extract to 50°C and let it stand for 1 hour, then heat it to 100°C and hold for 5 minutes. Step 3: The extract is subjected to high-pressure homogenization at a pressure of 100 MPa for 10 min; Step 4: Spray dry the homogenized extract with an inlet air temperature of 135℃, an outlet air temperature of 68℃, a fan frequency of 55 Hz, and a feed flow rate of 8 mL / min.

[0035] The Dendrobium officinale powders obtained in Examples 1-5 and Comparative Example 1 were evaluated, and the specific evaluation indicators are as follows: 1. Solubility Solubility was determined using the aluminum box constant weight method. The determination steps are as follows: Place a clean, covered aluminum box in a 105℃ oven and heat for 60 min. Remove the box and cool it in a desiccator for 30 min. Weigh the box and repeat the drying process until the difference between the two weighings does not exceed 2 mg, which is considered constant weight. Quantitatively dissolve the Dendrobium officinale powder sample in ultrapure water and stir continuously at 40℃ for 30 min. Then centrifuge at 4000 r / min for 15 min. Take a certain amount of supernatant in a dried, constant-weight aluminum box and dry it at 105℃ until constant weight. Retain the last constant weight value. Calculate the solubility using the following formula: Solubility (%) = Weight of solids after drying the quantitative supernatant (g) / (Initial solution concentration (g / mL) × Volume of supernatant taken (mL)) × 100.

[0036] 2. Total sugar content in Dendrobium powder Total sugar content was determined using the phenol-sulfuric acid method.

[0037] 3. Dispersion The dispersibility evaluation steps are as follows: Take an appropriate amount of Dendrobium officinale powder sample and place it in a beaker. Add water and stir. Record the time taken from the start of stirring until the powder is completely dispersed without clumping. This time is used to measure the dispersibility of the powder. The shorter the dispersion time, the better the dispersibility of the powder.

[0038] 4. Stratification rate The steps for evaluating the stratification rate are as follows: Take an appropriate amount of Dendrobium officinale powder sample and place it in a beaker. Add water and stir until the powder is completely dispersed and there are no lumps. Stop stirring and let it stand for a period of time. Record the height of the clear liquid precipitated on the upper layer and the total height of the liquid surface. The ratio of the two is the stratification rate.

[0039] 5. Molecular weight of polysaccharides contained in Dendrobium powder The molecular weight of the polysaccharide was determined by gel permeation chromatography (GPC).

[0040] 6. Bulk density The steps for evaluating the stratification rate are as follows: Weigh an appropriate amount of Dendrobium officinale powder sample into a graduated cylinder, oscillate it on a vortex shaker for an appropriate time, record the graduated cylinder scale, and then calculate the mass per unit volume according to the formula.

[0041] 7. Sensory evaluation Sensory evaluation was conducted under the following conditions: 15 g of Dendrobium powder was prepared by mixing 225 mL of 80℃ hot water, stirring for 30 s, and then allowed to stand for 2 min for evaluation. The evaluation results are shown in Table 1.

[0042] Table 1 Sensory Evaluation Content Table

[0043] The test results of Dendrobium officinale powder obtained in Examples 1-5 and Comparative Example 1 are shown in Table 2, and the sensory evaluation results are shown in Table 3.

[0044] Table 2. Solubility, Total Sugar Content, Dispersibility, Separation Rate, Molecular Weight, Bulk Density

[0045] Table 3 Sensory Evaluation Form

[0046] Table 2 shows that the solubility of Dendrobium officinale powder was significantly improved by enzymatic hydrolysis with glycosidases. Hydrolysis with glucanase and mannanase increased solubility by 6.5 times and 5.5 times, respectively; dual-enzyme hydrolysis increased solubility by 8.5–9 times. Simultaneously, the dual-enzyme hydrolysis method described in this invention increased the content of polysaccharides—the effective substance—in Dendrobium officinale powder by 1.56 times. The dispersibility and bulk density of the Dendrobium officinale powder solution after enzymatic hydrolysis were improved, the stratification rate was reduced, and the solution was more stable. Measurement of the molecular weight of polysaccharides in Dendrobium officinale powder revealed that the molecular weight of Dendrobium officinale polysaccharides before enzymatic hydrolysis was 141.2 kJ, while the molecular weight decreased by 1.6 times after single-enzyme hydrolysis and by 5.42 times after dual-enzyme hydrolysis. The results indicate that the enzymatic hydrolysis process specifically cleaves the glycosidic bonds in the polysaccharide chains, degrading them into smaller oligosaccharides, disaccharides, or monosaccharides, thereby increasing solubility. As shown in Table 3 above, the Dendrobium powder prepared by this invention has high acceptability, and after mixing, it has a clear, uniform color, good transparency, and a fresh, pleasant herbal aroma unique to Dendrobium, without any unpleasant odor. All of the above demonstrates that the Dendrobium powder prepared by this invention has significant effects and good development prospects.

Claims

1. A method for preparing highly soluble Dendrobium officinale powder based on enzymatic hydrolysis of polysaccharides, characterized in that: Dendrobium officinale powder obtained by crushing, grinding and sieving dried Dendrobium officinale strips is added to purified water to obtain Dendrobium officinale dispersion; the dispersion is heated in a water bath at 90~100℃ for 1~2 h, centrifuged and the supernatant is collected to obtain extract; glycosidase is added to the extract and enzymatically hydrolyzed at 40~60℃ for 1~1.5 h to inactivate the enzyme, homogenized under high pressure and spray dried to obtain highly soluble Dendrobium officinale powder.

2. The preparation method according to claim 1, characterized in that: The glycosidase is one or more of cellulase, pectinase, glucanase or mannanase.

3. The preparation method according to claim 2, characterized in that: The glycosidase is a combination of glucanase and mannanase.

4. The preparation method according to claim 1, characterized in that: The mass ratio of the dried Dendrobium officinale powder to purified water is 1:5~10.

5. The preparation method according to claim 1, characterized in that: The amount of glycosidase added is 0.5‰ to 1‰ of the total mass of the Dendrobium officinale dispersion.

6. The preparation method according to claim 1, characterized in that: Dendrobium officinale dried strips obtained by drying or freeze-drying are crushed and ground by a grinder and passed through a 100-mesh sieve to obtain Dendrobium officinale powder.

7. The preparation method according to claim 1, characterized in that: The enzymatically hydrolyzed Dendrobium officinale dispersion was heated to 90-100℃ and held for 5-8 minutes to inactivate the enzyme.

8. The preparation method according to claim 1, characterized in that: The high-pressure homogenization pressure is 100~200 MPa, and the time is 10~15 min.

9. The preparation method according to claim 1, characterized in that: The spray drying conditions are: inlet temperature 130~150℃, outlet temperature 80~90℃, fan frequency 50~60 Hz, and feed flow rate 8~10 mL / min.

10. The highly soluble Dendrobium officinale powder prepared by the method according to any one of claims 1 to 8.

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