Black tea processing method for directionally releasing sweet flower fragrance characteristic components based on exogenous enzyme targeted regulation and control of glucoside hydrolysis

Abstract

The invention discloses a black tea processing method for directionally releasing sweet flower fragrance characteristic components based on exogenous enzyme targeted regulation and control of glucoside hydrolysis. The black tea processing method comprises the following steps: withering fresh leaves, performing enzymatic treatment, performing gradient rolling, performing temperature-controlled humidity-controlled fermentation, and performing gross fire-spreading airing-complete fire staged drying on the fermented tea leaves, an enzyme solution sprayed for enzymatic treatment comprises one or more of an alpha-galactosidase solution with the activity being 0.5 to 0.6 U / mL, a beta-glucosidase solution with the activity being 0.6 to 0.7 U / mL, a cellulase solution with the activity being 200 to 210 U / mL and a papain solution with the activity being 1600 to 1700 U / mL; the sweet flower fragrance characteristic components comprise at least one of beta-myrcene, junifolene, citral, linalool, methyl salicylate, geraniol and nerol. The method solves the industrial problems of insufficient release of sweet flower fragrance characteristics, poor process stability and high dependence degree of raw materials in traditional black tea processing.

Description

Technical Field

[0001] The invention relates to the technical field of black tea processing, and in particular to a black tea processing method based on exogenous enzyme-targeted regulation of glycoside hydrolysis to release sweet floral aroma characteristic components. Background Art

[0002] As one of the most consumed teas globally, the aroma quality of black tea is a key factor in determining its market competitiveness. The sweet floral aroma, a hallmark of high-quality black tea, primarily originates from volatile compounds (such as geraniol and methyl salicylate). These compounds are typically present in the fresh leaves as non-volatile glycoside-bound compounds and are released through enzymatic hydrolysis during processing.

[0003] Traditional black tea processing relies on the natural action of endogenous enzymes in tea leaves, but has the following limitations:

[0004] ① Insufficient endogenous enzyme activity: The endogenous enzyme activity of tea is significantly affected by the variety, picking season and processing conditions (such as temperature and pH). Especially during the rolling and fermentation stages, the enzyme activity fluctuates greatly, resulting in low glycoside hydrolysis efficiency and unstable production of characteristic aroma components.

[0005] ② Poor glycoside substrate specificity: Different glycosidic bonds require specific enzymes to catalyze hydrolysis, but endogenous enzymes have weak catalytic ability for glycoside precursors, which limits the directional release of sweet floral characteristic compounds.

[0006] ③ Extensive process control: Traditional fermentation relies on the regulation of temperature and humidity in the natural environment, which makes it difficult to accurately match the optimal conditions for enzymatic reactions. This can easily cause excessive oxidation or incomplete hydrolysis of aroma precursors, resulting in a lack of prominent sweet floral aroma characteristics and mixed aromas.

[0007] In order to enhance the aroma of black tea, existing technologies (such as CN107467266A, etc.) have attempted to add exogenous enzymes (such as laccase, cellulase, etc.) to assist in processing, but their goals are mostly to accelerate cell wall fragmentation or improve fermentation efficiency, rather than to target the release of sweet floral aroma precursors. For example: Patent CN201610989859.9 proposes "a reprocessing method for improving the quality of raw tea or finished tea", which improves the quality of tea by using a composite enzyme preparation, but does not target specific aroma types (such as sweet floral aroma). The current market demand for black tea with sweet floral aroma is growing, but existing processing technologies make it difficult to achieve targeted enhancement and stable control of aroma types, resulting in high-end products relying on scarce raw materials, which restricts industrial upgrading. Summary of the Invention

[0008] In response to the above-mentioned technical problems and the shortcomings in the art, the present invention provides a method for processing black tea based on the targeted regulation of glycoside hydrolysis by exogenous enzymes for the directional release of sweet floral aroma characteristic components. The present invention proposes the core technology of "targeted regulation of glycoside hydrolysis by exogenous enzymes for the directional release of sweet floral aroma characteristic components". By introducing exogenous enzymes such as exogenous α-galactosidase, the aroma precursor substances bound by bonds such as α-galactosidase in tea leaves are specifically hydrolyzed, breaking through the substrate specificity limitation of endogenous enzymes; the enzyme activity window period is precisely regulated by the temperature and humidity control fermentation process to avoid the oxidation loss of aroma components and achieve the directional enrichment of sweet floral aroma substances; the timing of adding exogenous enzymes (before the rolling stage) and the dosage control scheme are designed to ensure that the technology can be applied on a large scale and avoid the problems of high cost and complex operation of traditional enzymatic hydrolysis methods. Compared with traditional methods, the present invention solves the industry problem of imprecise and unstable regulation of the sweet floral aroma of black tea from multiple angles such as enzyme-substrate matching, coordinated optimization of process parameters, and industrial adaptability, providing a new idea for the processing of high-fragrant and high-quality black tea.

[0009] A black tea processing method based on targeted regulation of glycoside hydrolysis by exogenous enzymes to release sweet floral aroma characteristic components, comprising the following steps:

[0010] (1) Withering of fresh leaves: Place fresh white tea leaves with one bud and two leaves in a well-ventilated place indoors for natural withering until the moisture content of the tea leaves drops to 60% to 62%, thereby obtaining withered leaves;

[0011] (2) Enzymatic treatment: spraying an enzyme solution uniformly on the surface of the wilted leaves at a spraying rate of 40 to 50 mL / kg of fresh leaves; the enzyme solution comprises one or more of an α-galactosidase solution having an activity of 0.5 to 0.6 U / mL, a β-glucosidase solution having an activity of 0.6 to 0.7 U / mL, a cellulase solution having an activity of 200 to 210 U / mL, and a papain solution having an activity of 1600 to 1700 U / mL;

[0012] (3) Gradient rolling: The enzymatically treated tea leaves are rolled according to the following procedure: air rolling for 25-26 min → light rolling for 20-21 min → heavy rolling for 10-11 min → light rolling for 15-16 min → air rolling for 5-6 min;

[0013] (4) Temperature and humidity controlled fermentation: After the gradient rolling is completed, the rolled leaves are deblocked and fermented at 28-32°C and 95%±0.1% relative humidity (RH) for 3.5±0.5h;

[0014] (5) The fermented tea leaves are dried in stages: rough fire, spreading and airing, and full fire:

[0015] Rough fire: 110±0.2℃ hot air drying to moisture content of 15±1%;

[0016] Spread to dry: Spread to dry at room temperature for 30 to 32 minutes;

[0017] Full fire: 90±0.1℃ hot air drying until the moisture content is ≤6%;

[0018] The characteristic components of the sweet floral fragrance include at least one of β-myrcene, cadinene, citral, linalool, methyl salicylate, geraniol, and nerol.

[0019] In some embodiments, in step (1), the fresh white tea leaves are fresh Fuding Dabaicha leaves.

[0020] In some embodiments, during the withering of fresh leaves in step (1), the leaves are spread to a thickness of 2 cm and are turned over every 120 minutes.

[0021] In some embodiments, the gradient kneading in step (3) is performed in a kneading machine at a kneading frequency of 45 to 50 r / min.

[0022] In some embodiments, step (3) gradient kneading is performed at 25°C.

[0023] In some embodiments, in step (4), the fermentation is carried out in a fermenter.

[0024] In some embodiments, in the rough fire of step (5), box-type hot air drying is adopted, and the drying time is 20 to 21 minutes.

[0025] In some embodiments, in step (5), box-type hot air drying is used for the full fire, and the drying time is 20 to 21 minutes.

[0026] The present invention utilizes enzymatic treatment technology, such as the introduction of α-galactosidase, to accelerate the hydrolysis of glycosides, leading to a targeted increase of 8.2% in the production of glycoside-derived volatiles. Specifically, the production of sweet floral black tea components such as geraniol and methyl salicylate increased by 17.79% and 21.50%, respectively. The resulting black tea exhibits a sweet and mellow flavor, a bright red tea liquor, and a strong, long-lasting sweet floral aroma, effectively enhancing the aroma quality of the tea.

[0027] The present invention significantly enhances the intensity and stability of the sweet floral aroma of black tea by introducing exogenous enzymes such as α-galactosidase to target and regulate the glycoside hydrolysis pathway, combined with a precise fermentation process. Specific beneficial effects include:

[0028] 1. Targeted enrichment of characteristic compounds of sweet floral aroma, significantly improving aroma quality. High targeted hydrolysis efficiency: Exogenous α-galactosidase specifically acts on α-galactosidic bonds, which can release characteristic components of sweet floral aroma (such as geraniol, methyl salicylate, etc.) in a targeted manner, avoiding the aroma mixing caused by broad-spectrum enzymatic hydrolysis.

[0029] 2. The process is highly adaptable and has significantly improved stability. By quantitatively adding exogenous enzymes before the rolling stage, combined with fermentation temperature control (28-32°C) and humidity control (95% ± 0.1% RH), the enzyme activity is ensured to be in the optimal window period, and the fluctuation rate of glycoside hydrolysis efficiency is relatively small.

[0030] 3. Break through raw material dependence and reduce production costs. By using exogenous enzymes to compensate for the lack of endogenous enzyme activity, even if low-end fresh leaves (such as one-bud two-leaf Fuding Dabai summer and autumn tea) are used, it is still possible to stably produce black tea with a sweet and floral aroma, reducing dependence on scarce spring tea raw materials.

[0031] The present invention uses exogenous enzyme targeted regulation technology to solve the industry problems of insufficient release of sweet floral aroma characteristics, poor process stability, and high dependence on raw materials in traditional black tea processing. It combines technological innovation, economic feasibility and market adaptability, providing an efficient and reliable solution for upgrading the quality of black tea. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is an analysis chart of 72 aroma components identified based on GC-MS / MS technology in a specific embodiment, including: (a) the proportion of different types of compounds; (b) a comparative analysis chart of compound categories under different enzyme treatments.

[0033] Figure 2 Graphs analyzing the effects of different exogenous enzymes on key aroma components in a specific embodiment, including: (a) a diagram of the categories of key aroma components; and (b) a comparison of the contents of key aroma components under different exogenous enzymes.

[0034] Figure 3 This is a comparative analysis of the effects of different exogenous enzyme treatments on the characteristic components of sweet floral aroma in a specific embodiment. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with the accompanying drawings and specific examples. It should be understood that these examples are intended to illustrate the present invention and are not intended to limit the scope of the invention. The operating methods in the following examples where no specific conditions are specified are generally performed under conventional conditions or as recommended by the manufacturer.

[0036] 1 Experimental part

[0037] 1.1 Instruments and devices

[0038] Triple quadrupole gas chromatograph-mass spectrometer, Agilent 7890B-7000C, USA; constant temperature mixer, Hangzhou Miou Instrument Co., Ltd.; electronic balance, Beijing Sartorius Scientific Instrument Co., Ltd.; 6CR-25 tea rolling machine, Zhejiang Chunjiang Tea Machinery Co., Ltd.; 6CJK-20 deblocking machine, Zhejiang Lvfeng Machinery Co., Ltd.; JY-6CFJ-0.7 black tea fermentation machine, Fujian Jiayou Tea Machinery Intelligent Technology Co., Ltd.; 6CHT-16 box-type aroma extractor, Zhejiang Zhufeng Machinery Co., Ltd.

[0039] 1.2 Materials and Reagents

[0040] This study used fresh leaves of Fuding Dabai tea as experimental materials, which were collected from the Shengzhou Experimental Base of the Tea Research Institute of the Chinese Academy of Agricultural Sciences. The picking standard was one bud and two leaves, the fresh leaf moisture content was 79.44%, and the picking time was early April 2024; 20mL headspace bottles and matching 18mm magnetic PTFE / silicone caps were purchased from Agilent, USA; purified water was purchased from Hangzhou Wahaha Group Co., Ltd.; SPME handle and DVB / CAR / PDMS extraction head were purchased from Supelco, USA.

[0041] 1.3 Tea making process

[0042] The picked one bud and two leaves of Fuding Dabai were withered indoors naturally in a ventilated place indoors, with the leaves spread to a thickness of 2 cm, and the leaves were turned over every two hours or so. Withering was stopped when the moisture content of the tea dropped to 60% to 62%. Then, before rolling, α-galactosidase solution (0.5U / mL), β-glucosidase (0.6U / mL), cellulase (200U / mL), papain (1600U / mL) and pure water (as a control or blank) were sprayed at a ratio of 40mL of aqueous solution per kg of tea, mixed and mixed well, and the rolling temperature was 25°C. The rolling procedure was air rolling for 25min→light rolling for 20min→heavy rolling for 10min→light rolling for 15min→air rolling for 5min, and the rolling frequency was 45r / min. After the rolling was completed, the rolled leaves were deblocked by a deblocking machine. The deblocked tea leaves were placed in a fermentation machine for temperature and humidity controlled fermentation, set at 28°C and 95%. RH, ferment for 3-4h; carry out rough drying in a box-type drying oven, set the temperature to 110℃, and dry for 20min, until the moisture content of the tea drops to about 15%, then end the rough drying; after spreading for half an hour, carry out full drying, set the temperature to 90℃, and dry for 20min, until the tea is fully dry (moisture content ≤ 6%).

[0043] 1.4 Sensory Evaluation

[0044] A sensory evaluation panel of six professionally trained experts (three men and three women) from the Tea Research Institute of the Chinese Academy of Agricultural Sciences evaluated tea samples treated with various exogenous enzymes according to the national tea evaluation standard GB / T 23776-2018. The specific procedure was as follows: First, 3g of tea sample was added to 150mL of boiling water. After brewing for 5 minutes, the tea was filtered and aroma was evaluated. Hot, warm, and cold sniffing were used to assess the type, intensity, and persistence of the aroma.

[0045] 1.5HS-SPME Technology

[0046] Using an electronic balance, 0.5 g of tea leaves were accurately weighed and placed in a 20 mL headspace vial. 5 mL of purified water was added and the cap was tightly closed. A DVB / CAR / PDMS fiber was inserted into the headspace vial to absorb volatile components and then secured in a thermomixer for aroma enrichment. Extraction was performed at a constant temperature of 60°C for 60 minutes. After extraction, the fiber tip was inserted into the GC-MS inlet and desorbed at 250°C for 5 minutes. Each sample was tested in triplicate.

[0047] For non-targeted qualitative and quantitative compounds, 2 μL of ethyl decanoate (concentration of 50 mg / L) and 0.5 g of tea leaves were added to the headspace bottle, and the extraction and detection were performed according to the same operating procedures as above.

[0048] 1.6 GC-MS / MS analysis

[0049] GC analysis conditions: A DB-5MS capillary gas chromatography column (30 m × 0.25 mm × 0.25 μm) was used, with helium (99.999% purity) as the carrier gas at an inlet rate of 1 mL / min in splitless mode. The chromatographic temperature program was as follows: initial temperature 40°C, hold for 5 minutes, followed by a temperature increase at 4°C / min to 160°C, hold for 5 minutes, with splitless injection. MS was performed in electron ionization (EI) mode with an energy of 70 eV and a mass scan range of 40-450 m / z. The ion source and sensor line temperatures were 230°C and 270°C, respectively.

[0050] 1.7 Accurate Qualitative and Quantitative Analysis of Aroma Compounds

[0051] Qualitative analysis was performed using Agilent MassHunter software, validated with the NIST 11.0 spectral library and standards, and compound identification was performed using the retention index of n-alkanes (C7-C40). Quantitative analysis employed a calibration curve method, constructing a standard curve using mixed calibration solutions with varying concentration gradients. For compounds for which commercially available standards were unavailable, internal standards were used for semi-quantification.

[0052] 1.8 OAV Analysis

[0053] OAV (Aroma Activity Value) is a commonly used method to evaluate the aroma of tea leaves using volatile compounds. It is calculated by dividing the concentration (C) of a volatile compound by the perception threshold (OT) of that compound in water. The specific formula is: OAV = C / OT.

[0054] 2 Results and Analysis

[0055] 2.1 Effects of different exogenous enzyme treatments on the aroma sensory quality of black tea

[0056] We conducted an aroma sensory evaluation of black tea samples treated with different exogenous enzymes. The results are shown in Table 1. The α-galactosidase-treated group had the highest aroma score (90.02), exhibiting a distinct sweet and floral aroma. The β-glucosidase-treated group followed closely behind (89.08), exhibiting a slightly floral aroma. Furthermore, while the aroma of the control group, papain, and cellulase-treated groups all had a sweet aroma, the aroma scores of the papain and cellulase-treated groups were significantly higher than those of the control group (p < 0.05), indicating that papain and cellulase may improve the aroma quality of black tea to some extent.

[0057] Table 1 Sensory evaluation results of tea samples treated with different exogenous enzymes

[0058]

[0059] Note: Different letters indicate significant differences (p<0.05).

[0060] 2.2 Comparative analysis of aroma component content of tea samples treated with different exogenous enzymes

[0061] The volatile compounds of black tea samples treated with different exogenous enzymes were analyzed using GC-MS / MS technology, and a total of 72 volatile compounds were identified. These compounds cover nine categories, including 19 esters, 17 aldehydes, 15 alcohols, 8 ketones, 5 alkenes, 4 aromatic compounds, 2 phenols, 1 acid and 1 other category. Among the 72 volatile compounds summarized in all experimental groups, esters, aldehydes and alcohols accounted for the highest proportions, at 26.39%, 23.61% and 20.83% respectively ( Figure 1 a).

[0062] Further analysis revealed that different exogenous enzyme treatments had significant effects on the types of volatile compounds ( Figure 1 b) The ester content in the α-galactosidase group was significantly higher than in the other groups (p < 0.05). Furthermore, the α-galactosidase treatment also resulted in relatively higher levels of alcohols, aldehydes, and certain phenols (eugenol), compounds that contribute to the aroma quality of black tea.

[0063] 2.3 Analysis of the effects of different exogenous enzymes on key aroma components

[0064] In addition, 31 key volatile compounds that significantly contribute to the aroma quality of black tea were screened out through OAV analysis. To explore the regulatory effect of exogenous enzymes on the aroma components of black tea, the identified volatile compounds were classified into four categories according to their sources ( Figure 2 a): fatty acid-derived volatiles (FADVs, a total of 11 types), amino acid-derived volatiles (AADVs, a total of 7 types), glycoside-derived volatiles (GDVs, a total of 7 types) and carotenoid-derived volatiles (CDVs, a total of 6 types). The results showed that different exogenous enzyme treatments showed significant differences in the regulation of the above four types of volatile metabolites, especially glycosidase treatment (α-galactosidase and β-glucosidase) had the most significant effect on the increase in the content of these volatile compounds ( Figure 2 b) Combining sensory evaluation with the aforementioned aroma compound analysis results, we found that the aroma quality of tea samples treated with glycosidases was significantly superior to that of the other groups. Of the 31 key volatile compounds, seven were classified as GDVs, including β-myrcene, cadinene, citral, linalool, methyl salicylate, geraniol, and nerol. Therefore, this study further focused on the regulatory changes in glycoside-derived volatiles to clarify the potential mechanism by which exogenous enzymes improve the aroma quality of black tea.

[0065] Glycoside compounds exist mainly in the form of glycosides in fresh tea leaves. During the tea-making process, they can be hydrolyzed under the catalysis of endogenous glycosidases to produce floral, sweet and fruity volatiles. The aglycone part is usually terpenes, demethyl isoprenoids, aromatic derivatives or long-chain fatty alcohols, and the glycosyl part is mostly composed of disaccharides such as β-D-glucose or rhamnose, galactose and xylose. Since a single glycosidase can act on multiple GDVs substrates, it is difficult to establish a one-to-one correspondence between precursors and aromatic products. Figure 2 As shown in b, glycosidase treatment significantly promoted the increase in GDVs content, and the GDVs content of α-galactosidase and β-glucosidase increased by 8.2% and 5.2%, respectively. These typical terpene alcohol compounds usually give tea a floral, sweet or fruity aroma and are the characteristic components of sweet floral black tea. In addition, the results of this study showed that ( Figure 3), the content changes of nerol, linalool, methyl salicylate, and geraniol were relatively consistent with the overall changes in GDVs, reaching high levels in the glycosidase-treated group. In addition, among the four exogenous enzyme-treated groups, the contents of five typical GDVs, cadinene, linalool, methyl salicylate, geraniol, and nerol, were the highest after treatment with α-galactosidase and β-galactosidase. Further comparison revealed that, with the exception of linalool, the contents of the other four compounds were slightly higher in the α-galactosidase-treated group than in the β-glucosidase-treated group, while linalool was higher in the β-glucosidase-treated group. This indicates that although both glycosidases can effectively promote the accumulation of GDVs, there are certain differences in their effects on different aroma components. Among them, α-galactosidase exhibits a stronger enhancement ability in most components and has greater aroma regulation potential.

[0066] In summary, distinct differences were observed in the regulatory effects of different exogenous enzyme treatments on the glycoside-derived volatile components of black tea, with glycosidases performing the best. α-galactosidase, in particular, demonstrated superior regulatory effects over β-glucosidase on the accumulation of most key GDVs. Both α-galactosidase and β-glucosidase significantly promoted the production of floral aroma-related components such as nerol, geraniol, and methyl salicylate. This result not only reveals the central role of glycosidases in enhancing the aroma quality of black tea but also provides a theoretical basis and practical reference for optimizing the floral aroma characteristics of black tea through targeted exogenous enzyme intervention.

[0067] In addition, it should be understood that after reading the above description of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A method for processing black tea based on targeted regulation of glycoside hydrolysis by exogenous enzymes to release sweet floral aroma components, characterized in that: Including steps: (1) Withering of fresh leaves: Place fresh white tea leaves with one bud and two leaves in a well-ventilated place indoors for natural withering until the moisture content of the tea leaves drops to 60% to 62%, thereby obtaining withered leaves; (2) Enzymatic treatment: spraying an enzyme solution uniformly on the surface of the wilted leaves at a spraying rate of 40 to 50 mL / kg of fresh leaves; the enzyme solution comprises one or more of an α-galactosidase solution having an activity of 0.5 to 0.6 U / mL, a β-glucosidase solution having an activity of 0.6 to 0.7 U / mL, a cellulase solution having an activity of 200 to 210 U / mL, and a papain solution having an activity of 1600 to 1700 U / mL; (3) Gradient rolling: The enzymatically treated tea leaves are rolled according to the following procedure: air rolling for 25-26 min → light rolling for 20-21 min → heavy rolling for 10-11 min → light rolling for 15-16 min → air rolling for 5-6 min; (4) Temperature and humidity controlled fermentation: After the gradient rolling is completed, the rolled leaves are deblocked and fermented at 28-32°C and 95% ± 0.1% relative humidity for 3.5 ± 0.5 h; (5) The fermented tea leaves are dried in stages: rough fire, spreading and airing, and full fire: Rough fire: 110±0.2℃ hot air drying to moisture content of 15±1%; Spread to dry: Spread to dry at room temperature for 30 to 32 minutes; Full fire: 90±0.1℃ hot air drying until the moisture content is ≤6%; The characteristic components of the sweet floral fragrance include at least one of β-myrcene, cadinene, citral, linalool, methyl salicylate, geraniol, and nerol.

2. The black tea processing method based on exogenous enzyme targeted regulation of glycoside hydrolysis to release sweet floral aroma characteristic components according to claim 1, characterized in that: In step (1), the fresh white tea leaves are fresh Fuding Dabaicha leaves.

3. The black tea processing method based on exogenous enzyme targeted regulation of glycoside hydrolysis to release sweet floral aroma characteristic components according to claim 1, characterized in that: During the withering process of the fresh leaves in step (1), the leaves were spread to a thickness of 2 cm and turned over every 120 minutes.

4. The black tea processing method based on exogenous enzyme targeted regulation of glycoside hydrolysis to release sweet floral aroma characteristic components according to claim 1, characterized in that: Step (3) gradient kneading is carried out in a kneading machine with a kneading frequency of 45 to 50 r / min.

5. The black tea processing method based on exogenous enzyme targeted regulation of glycoside hydrolysis to release sweet floral aroma characteristic components according to claim 1, characterized in that: Step (3) gradient kneading is carried out at 25°C.

6. The method for processing black tea based on exogenous enzyme targeted regulation of glycoside hydrolysis to release sweet floral aroma characteristic components according to claim 1, characterized in that: In step (4), fermentation is carried out in a fermentation machine.

7. The method for processing black tea based on exogenous enzyme targeted regulation of glycoside hydrolysis to release sweet floral aroma characteristic components according to claim 1, characterized in that: In the rough fire of step (5), box-type hot air drying is adopted, and the drying time is 20 to 21 minutes.

8. The method for processing black tea based on exogenous enzyme targeted regulation of glycoside hydrolysis to release sweet floral aroma characteristic components according to claim 1, characterized in that: In step (5), box-type hot air drying is adopted for the full fire, and the drying time is 20 to 21 minutes.

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