Preparation process of anti-oxidation cistanche freeze-dried powder

Abstract

This invention discloses a process for preparing freeze-dried Cistanche deserticola powder with anti-oxidation properties, belonging to the field of traditional Chinese medicine technology. The preparation process is as follows: Fresh Cistanche deserticola is cleaned and impurities are removed, surface moisture is drained, and it is sliced ​​into thin slices. The slices are then immersed in a container filled with purified water. The soaking system and container are pre-frozen together. The pre-frozen whole slices are then freeze-dried and pulverized to obtain freeze-dried Cistanche deserticola powder. This invention effectively avoids the oxidation reaction of Cistanche deserticola during drying, increasing the content of phenylethanoid glycosides. Simultaneously, the freeze-dried Cistanche deserticola powder prepared by this invention can remain unoxidized for a long time in air at room temperature and humidity below 40%, maintaining a snow-white to yellowish-white color, significantly enhancing the product's storage stability and commercial appearance quality.

Description

Technical Field

[0001] This invention relates to the field of traditional Chinese medicine technology, and more specifically, to a process for preparing freeze-dried Cistanche deserticola powder with anti-oxidation properties. Background Technology

[0002] Studies have found that the fleshy part of fresh Cistanche deserticola is highly susceptible to oxidation in aerobic environments. Once sliced ​​and exposed to air, the cut surface will turn brown to black within minutes due to oxidation, and the taste will become bitter and unpalatable. Analysis of the content of phenylethanoid glycosides, the antioxidant active ingredient in Cistanche deserticola, revealed a significant decrease in the content of phenylethanoid glycosides (calculated as the total content of echinacoside and verbascoside) after oxidation. Currently, freshly harvested Cistanche deserticola is mostly dried using traditional methods such as sun-drying and shade-drying, which inevitably lead to oxidation. Regarding freeze-drying technology for Cistanche deserticola, currently published invention patents (such as patent publication number CN113181243A) only focus on the "preservation" needs of Cistanche deserticola and do not address its oxidation problem. Developing a new process that effectively avoids oxidation during drying and increases the content of phenylethanoid glycosides would have significant application value. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide an oxidation-resistant freeze-dried Cistanche deserticola powder preparation process, which can effectively avoid the oxidation reaction of Cistanche deserticola during drying and increase the content of phenylethanoid glycosides.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A process for preparing freeze-dried Cistanche deserticola powder with anti-oxidation properties involves removing impurities from fresh Cistanche deserticola, cleaning it thoroughly, draining the surface moisture, slicing it into thin slices, immersing it in a container filled with purified water, pre-freezing the soaking system and the container together, then freeze-drying the pre-frozen whole Cistanche deserticola slices into ice blocks and pulverizing them to obtain freeze-dried Cistanche deserticola powder.

[0006] Furthermore, the mass ratio of the flakes to purified water is 1:6-8.

[0007] Furthermore, the pre-freezing temperature is -10℃ to -50℃, and the pre-freezing time is 4-6 hours.

[0008] Furthermore, the initial freeze-drying temperature is -35℃ to -45℃, the freeze-drying time is 25-35h, the drying completion temperature is 38-45℃, and the vacuum degree of the entire freeze-drying process is 2-4Pa.

[0009] Furthermore, the moisture content of freeze-dried Cistanche deserticola powder is less than 6%.

[0010] Furthermore, the thickness of the sheet is 3-6 mm.

[0011] In summary, the present invention has the following beneficial effects:

[0012] This invention rapidly encapsulates fresh Cistanche deserticola slices in purified water, creating a solid ice barrier on the cut surface to effectively block oxygen contact. Combined with specific low-temperature pre-freezing and freeze-drying processes, it minimizes oxidation during the freeze-dried powder processing. Compared to traditional sun-drying and freeze-drying methods, the freeze-dried powder produced using this process exhibits significantly higher levels of the characteristic antioxidant phenylethanoid glycosides (calculated as the total content of echinacoside and verbascoside), and a significantly reduced bitter taste. This effectively solves the technical challenges of oxidation and efficacy loss during Cistanche deserticola drying, thereby increasing the product's added value. Furthermore, the freeze-dried powder produced by this invention can remain unoxidized for extended periods in air at room temperature and humidity below 40%, maintaining a snow-white to yellowish-white color, significantly enhancing the product's storage stability and commercial appearance. Attached Figure Description

[0013] Figure 1 Image of the freeze-dried Cistanche deserticola powder sample prepared in Example 3;

[0014] Figure 2 The chromatogram is the mixed reference solution corresponding to the content detection of freeze-dried Cistanche deserticola powder in Example 3;

[0015] Figure 3 The chromatogram is of the test solution of the freeze-dried Cistanche deserticola powder prepared in Example 3. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Example 1

[0018] Take 1 kg of fresh Cistanche deserticola, remove impurities, quickly rinse the surface mud and sand with clean water, drain the surface water, and cut into thin slices with a thickness of 4 mm (the thickness of the slices can be controlled between 3-6 mm, and 4 mm is selected in this embodiment). Quickly put them into a container containing purified water, so that the slices are completely submerged (the mass ratio of slices to purified water can be controlled between 1:6-8, and 1:7.4 is used in this embodiment). Pre-freeze this soaking system and the container together at -10℃ for 6 hours; then remove the whole Cistanche deserticola slices frozen into ice blocks from the container and put them into a freeze dryer for drying (freeze drying conditions: first raise the temperature from the initial temperature of -40℃ to 20℃ at a rate of 8.6℃ / h). The temperature was then increased to 30℃ at a rate of 5℃ / h, followed by a further increase to 40℃ at a rate of 1.25℃ / h, and then held at that temperature for 12 hours. The vacuum degree throughout the freeze-drying process was 2.4 Pa. The freeze-drying conditions were adjusted according to the thickness of the Cistanche deserticola slices and the soaking ratio with purified water. The initial freeze-drying temperature was -35℃ to -45℃, the freeze-drying time was 25-35 hours, and the drying completion temperature was 38-45℃. A gradient heating drying mode was used, and the vacuum degree throughout the freeze-drying process was 2-4 Pa. After drying, the Cistanche deserticola was pulverized at room temperature and humidity ≤40% to obtain freeze-dried Cistanche deserticola powder with a particle size of 80-120 mesh. The obtained freeze-dried Cistanche deserticola powder, when placed in a sealed bag, can remain unoxidized for a long time (at least 120 days) in air at room temperature and humidity below 40%, and its color remains snow-white to yellowish-white.

[0019] Example 2

[0020] Take 1 kg of fresh Cistanche deserticola and prepare Cistanche deserticola freeze-dried powder according to the method in Example 1, except that it is pre-frozen at -30℃ for 5 hours. The prepared Cistanche deserticola freeze-dried powder is placed in a sealed bag and can remain non-oxidized for a long time (at least 120 days) in air at room temperature and ambient humidity below 40%, and its color is snow-white to yellowish-white.

[0021] Example 3

[0022] Take 1 kg of fresh Cistanche deserticola and prepare Cistanche deserticola freeze-dried powder according to the method in Example 1 (e.g. Figure 1 The difference is that it is pre-frozen at -50℃ for 4 hours. The resulting freeze-dried Cistanche deserticola powder, when placed in a sealed bag, can remain unoxidized for a long time in air at room temperature and humidity below 40%, and its color is snow-white.

[0023] Comparative Example 1

[0024] Take 1 kg of fresh Cistanche deserticola, remove impurities, quickly rinse the surface with clean water to remove dirt and sand, drain the surface water, and cut into thin slices with a thickness of 4 mm. Spread the sliced ​​Cistanche deserticola evenly on a clean bamboo sieve, ensuring the slices do not overlap, and place in a well-ventilated, sunny place to dry. Turn the slices three times a day during the drying process to prevent mold growth. After drying completely, pulverize the Cistanche deserticola slices to obtain Cistanche deserticola powder with a particle size of 80-120 mesh. The obtained powder is brown to black.

[0025] Comparative Example 2

[0026] Take 1 kg of fresh Cistanche deserticola, remove impurities, quickly rinse the surface with clean water to remove dirt and sand, drain the surface water, and cut into thin slices with a thickness of 4 mm. Spread the sliced ​​Cistanche deserticola evenly on a clean bamboo sieve, ensuring the slices do not overlap, and place it in a well-ventilated shade without direct sunlight to air dry. Turn it twice a day during the air drying period to maintain ventilation and prevent mold growth. After air drying until completely dry, pulverize the Cistanche deserticola slices to obtain Cistanche deserticola powder with a particle size of 80-120 mesh. The obtained powder is brown to black.

[0027] Comparative Example 3

[0028] Take 1 kg of fresh Cistanche deserticola, remove impurities, quickly rinse the surface with clean water to remove dirt and sand, drain the surface water, and cut into thin slices with a thickness of 4 mm. Spread the sliced ​​Cistanche deserticola evenly on a tray, ensuring that the slices do not overlap, and place it in an electric heating forced-air drying oven at 65℃ for drying. During the drying process, turn the slices over every 2 hours to ensure even heating. After drying completely, pulverize the Cistanche deserticola slices to obtain Cistanche deserticola dry powder with a particle size of 80-120 mesh. The obtained dry powder is brown to black.

[0029] Comparative Example 4

[0030] Take 1 kg of fresh Cistanche deserticola, remove impurities, quickly rinse the surface with clean water to remove mud and sand, drain the surface water, and cut into thin slices with a thickness of 4 mm. Pre-freeze directly at -10℃ for 6 hours (it was found that the cut surface began to oxidize after 3 minutes of pre-freezing). Place in a freeze dryer to dry (freeze drying is the same as in Example 1). After drying, pulverize the slices at room temperature and humidity ≤40% below 20℃ to obtain freeze-dried Cistanche deserticola powder with a particle size of 80-120 mesh. The obtained freeze-dried powder is brown to black.

[0031] The appearance, color, echinacoside, and verbascoside content of the Cistanche deserticola powder prepared in Examples 1-3 and Comparative Examples 1-4 were determined, and the results are shown in Table 1. The chromatogram of the mixed reference solution corresponding to the content determination of the freeze-dried Cistanche deserticola powder in Example 3 is shown in Table 1. Figure 2 As shown; the chromatogram of the freeze-dried Cistanche deserticola powder test solution prepared in Example 3 is shown below. Figure 3 As shown.

[0032] Table 1

[0033]

[0034] In the above embodiments and comparative examples, the Cistanche deserticola used was Cistanche deserticola Y.C.Ma, which was sourced from Zhejiang Renji Herbal Medicine Co., Ltd., with batch number RCR-YY-260310-01.

[0035] The detection methods for echinacoside and verbascoside are as follows:

[0036] (1) Preparation of mixed reference solution: Take appropriate amounts of echinacoside reference standard (from China National Institutes for Food and Drug Control, batch number 111670-202508) and verbascoside reference standard (from China National Institutes for Food and Drug Control, batch number 111530-202315), accurately weigh them, and add 50% (v / v) methanol to prepare a mixed reference solution containing about 0.2 mg of each of echinacoside and verbascoside per 1 mL.

[0037] (2) Preparation of test solution: Take an appropriate amount of the Cistanche deserticola powder (passed through a No. 4 sieve), weigh it accurately, put it in a 100mL brown volumetric flask, add 50mL of 50% (v / v) methanol accurately, stopper tightly, shake well, weigh, soak for 30 minutes, then sonicate for 40 minutes (power 250W, frequency 35kHz), cool, weigh again, add 50% (v / v) methanol to make up the lost weight, shake well, let stand, take the supernatant, filter, take the filtrate, and the test solution is obtained.

[0038] (3) Determination: Accurately pipette the mixed reference solution and the test solution into the high performance liquid chromatograph and determine them.

[0039] The liquid chromatography conditions are as follows:

[0040] Chromatographic column: Ultimate XB-C18, 4.6 × 250 mm, 5.0 μm; packed with octadecylsilane-bonded silica gel; mobile phase A: methanol; mobile phase B: 0.1% (v / v) formic acid solution; gradient elution as specified in Table 2; flow rate: 0.8 mL / min; detection wavelength: 330 nm; injection volume: 10 μL. The theoretical plate number, calculated based on the echinacoside peak, should be no less than 3000.

[0041] Table 2

[0042]

[0043] The echinacoside and verbascoside contents in the Cistanche deserticola powder samples of each embodiment and comparative example were calculated according to the following formula:

[0044] Content = C r×A x ÷A r ×V x ÷M x ;

[0045] In the formula: C r A represents the concentration of the analyte in the mixed reference solution, in mg / mL. x A represents the peak area of ​​the analyte in the test solution; r V represents the average peak area of ​​the analyte in the mixed reference solution; x The volume of the test solution is adjusted to the required volume in mL; M x The sample weight is in grams.

[0046] The concentrations of the analytes, sample weights, final volumes of the sample solution, peak areas of the analytes in the mixed reference solutions, and peak area data of the analytes in the sample solutions of each embodiment and comparative example in liquid chromatography detection are shown in Tables 3 and 4 (Note: The analyte content of the samples in Examples 1, 2, Comparative Examples 1 and 3 was calculated based on the average peak area of ​​the analytes in the same mixed reference solution; the analyte content of the samples in Examples 3 and 4 was calculated based on the average peak area of ​​the analytes in the same mixed reference solution).

[0047] Table 3

[0048]

[0049] Table 4

[0050]

[0051] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A process for preparing freeze-dried Cistanche deserticola powder with anti-oxidation properties, characterized in that, After cleaning and removing impurities from fresh Cistanche deserticola, drain the surface water, slice it into thin slices, and immerse it in a container of purified water. Pre-freeze the soaking system and the container together, then freeze-dry the pre-frozen whole Cistanche deserticola slices into ice blocks and pulverize them to obtain freeze-dried Cistanche deserticola powder.

2. The process for preparing an oxidation-resistant freeze-dried Cistanche deserticola powder according to claim 1, characterized in that, The mass ratio of the flakes to purified water is 1:6-8.

3. The process for preparing an antioxidant freeze-dried Cistanche deserticola powder according to claim 1, characterized in that, The pre-freezing temperature is -10℃ to -50℃, and the pre-freezing time is 4-6 hours.

4. The process for preparing an oxidation-resistant freeze-dried Cistanche deserticola powder according to claim 1, characterized in that, The initial freeze-drying temperature is -35℃ to -45℃, the freeze-drying time is 25-35h, the drying completion temperature is 38-45℃, and the vacuum degree of the entire freeze-drying process is 2-4Pa.

5. The process for preparing an oxidation-resistant freeze-dried Cistanche deserticola powder according to claim 1, characterized in that, The moisture content of freeze-dried Cistanche deserticola powder is less than 6%.

6. The process for preparing an antioxidant freeze-dried Cistanche deserticola powder according to claim 1, characterized in that, The thickness of the sheet is 3-6mm.

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