Fermentation preparation process for reducing cold and cool characteristics of fructus forsythiae tea

Abstract

The invention discloses a fermentation preparation process for reducing cold and cool characteristics of fructus forsythiae tea. The fermentation preparation process comprises the following steps: performing early-stage treatment of screening, weighing, cleaning, high-temperature softening, rolling and high-temperature steam sterilization on fructus forsythiae leaves; compounding lactobacillus plantarum and German-style lactobacillus bulgaricus to obtain a mixed strain, adding the mixed strain into the treated fructus forsythiae leaves, and putting into a fermentation box for solid-state fermentation; under a sterile condition, adding a fermentation strain of pichia guilliermondii BC 621 into the fructus forsythiae leaves subjected to solid-state fermentation, and putting into a fermentation box for secondary fermentation; and drying the fructus forsythiae leaves subjected to secondary fermentation until the water content is below 6%. Active components reflecting cold and cool characteristics in the fructus forsythiae tea prepared by the method are obviously reduced, the fructus forsythiae tea is also suitable for people with deficiency-cold spleen and stomach and deficiency-cold constitution to drink, and audiences are expanded.

Description

Technical Field

[0001] The invention relates to the technical field of tea processing technology, and in particular to a fermentation preparation process for reducing the cold property of forsythia tea. Background Art

[0002] The chemical composition of Forsythia suspensa leaves is similar to that of Forsythia suspensa. The Chinese Materia Medica records that "Forsythia suspensa stems and leaves are bitter, cold and non-toxic, and can treat heat accumulation in the heart and lungs". Forsythia suspensa leaves contain a variety of active substances that clear away heat and detoxify, such as forsythia glycosides, forsythia glycoside A, forsythia suspensa glycosides and other active ingredients. They not only have good health care effects but also have certain medicinal value. Therefore, people often make health tea by natural fermentation of Forsythia suspensa leaves. However, the traditional natural stacking fermentation method has a long fermentation cycle, and the fermentation process is difficult to control automatically. In addition, the content of cold substances in the naturally fermented Forsythia tea is high, which makes Forsythia tea bitter and cold in nature. It is not suitable for people with weak spleen and stomach or weak constitution. Summary of the invention

[0003] The purpose of the present invention is to provide a fermentation preparation process for reducing the cold property of Forsythia tea, effectively reduce the content of cold property substance components in Forsythia tea, improve the taste and quality of Forsythia tea, and make it more suitable for drinking by the general public.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] A fermentation preparation process for reducing the cold property of forsythia tea comprises the following steps:

[0006] Step 1: Preliminary treatment of the Forsythia suspensa leaves, including screening, weighing, washing, high temperature softening, rolling and high temperature steam sterilization;

[0007] Step 2: Compounding Lactobacillus plantarum and Lactobacillus bulgaricus in a volume ratio of (1-3):(3-1) to obtain a mixed strain, adding the mixed strain to the treated Forsythia suspensa leaves at an inoculum amount of 2-8% (v / w), placing the mixed strain in a fermentation box, setting the fermentation temperature at 28-37° C. and the fermentation time at 18-24 h for solid-state fermentation;

[0008] Step 3: under sterile conditions, adding the fermentation strain of Pichia guilliermong BC 621 at an inoculation rate of 4-10% (v / w) to the Forsythia suspensa leaves after solid-state fermentation, placing the leaves in a fermentation box, setting the fermentation temperature at 30-35° C. and the fermentation time at 48-72 h for secondary fermentation;

[0009] Step 4: Dry the Forsythia suspensa leaves after secondary fermentation until the water content is below 6%.

[0010] Further, the specific operation of the early stage treatment of the forsythia leaves in step 1 includes the following steps:

[0011] (1) Screening of Forsythia suspensa leaves: Pick the stems of dry Forsythia suspensa leaves cleanly and select leaves of uniform size and without insect pests;

[0012] (2) Weighing the raw material leaves of Forsythia suspensa: weigh 10-20 g of dry Forsythia suspensa leaves;

[0013] (3) Clean the weighed Forsythia suspensa leaves;

[0014] (4) High temperature softening: Put the cleaned Forsythia leaves into a steamer and steam them to fully soften them. After the steaming is completed, remove the clear water on the surface;

[0015] (5) rolling and twisting: spraying a protective liquid on the softened Forsythia suspensa leaves, wherein the protective liquid is a mixture of 1.5-3wt% citric acid and 0.5-1wt% sodium bicarbonate, and the spraying amount is 30-50mL per kilogram of Forsythia suspensa leaves; then rolling and twisting the Forsythia suspensa leaves repeatedly according to the principle of "light 2min-heavy 1min-light 2min" until the leaves are curled, the tea juice overflows, and the juice does not drip when the leaves are held in a ball;

[0016] (6) High-temperature steam sterilization: Place the rolled Forsythia suspensa leaves in a food-grade culture dish, wrap them with newspaper, and sterilize them at 121°C for 20-40 minutes.

[0017] Further, the preparation of the plant lactobacillus described in step 2 comprises the following steps: inoculating the plant lactobacillus lyophilized powder into the sterilized MRS liquid culture medium, placing it in a constant temperature shaking table, setting the temperature to 35°C, the rotation speed to 100-160rpm, culturing for 20-24h for the first activation, then accessing a 250mL triangular flask containing 100mL of new culture medium with an inoculum amount of 3-6% (v / w), standing and culturing at 35°C for 20-24h, and finally storing it in a 4°C refrigerator for standby use.

[0018] Furthermore, the preparation of the German Lactobacillus bulgaricus described in step 2 comprises the following steps: inoculating the German Lactobacillus bulgaricus freeze-dried powder into the sterilized MRS liquid culture medium, placing it in a constant temperature shaker set at a temperature of 37° C. and a rotation speed of 100 to 160 rpm for culturing for 20-24 hours for the first activation, then inoculating it into a 250 mL triangular flask containing 100 mL of new culture medium with an inoculum amount of 4-8% (v / w), culturing it at 37° C. for 20-24 hours, and finally storing it in a 4° C. refrigerator for standby use.

[0019] Further, the specific operation of compounding the plant lactobacillus and the German Lactobacillus bulgaricus described in step 2 comprises the following steps:

[0020] (1) activating and expanding the culture of Lactobacillus plantarum and Lactobacillus bulgaricus;

[0021] (2) The activated and expanded Lactobacillus plantarum and Lactobacillus bulgaricus were centrifuged, and the colony precipitates were collected and the bacterial solution concentration was adjusted to 5-6×10 6 cfu / mL;

[0022] (3) Compounding Lactobacillus plantarum and Lactobacillus bulgaricus in a volume ratio of (1-3):(3-1).

[0023] Furthermore, the preparation of the fermentation strain of Pichia quaternaria BC 621 described in step three includes the following steps: after activating the BC 621 strain on the wort medium, inoculate it into the slant culture medium, and culture it at a constant temperature of 28±1°C for 20-24h, then wash the slant culture lawn with sterile water to prepare a uniform bacterial suspension; then dilute the bacterial suspension with sterile water to an OD 600 of 0.600±0.002, inoculate it into a 100mL shake flask containing 50mL of liquid culture medium at an inoculum amount of 10% (v / w), and culture it at 28±1°C for 20-24h.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention first selects a mixed strain after Lactobacillus plantarum and German Lactobacillus bulgaricus are compounded to ferment Forsythia tea. By fermenting Forsythia leaves with compound strains, the effect of fermenting Forsythia leaves is better, and the content of active ingredients with cold and cool properties, such as forsythoside A and rutin in Forsythia leaves, can be reduced. Through microbial transformation, forsythoside is converted into forsythiaside, and the overall active ingredients with cold and cool properties in Forsythia leaves are reduced. Since fermenting Forsythia tea with a mixed strain after Lactobacillus plantarum and German Lactobacillus bulgaricus will cause the pH in Forsythia tea to decrease, a pH-tolerant strain (Pichia guillimonga BC 621) is added to continue deep fermentation of Forsythia leaves, and the content of components with cold and cool properties is reduced again, so that the biological activity is improved, the cold and cool properties are alleviated, and the nutrients in Forsythia leaves are more utilized and absorbed, and the flavor is more mellow. The fermented Forsythia tea has the characteristics of red, thick and bright tea soup, mellow taste, good taste, and good aroma quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the HPLC chromatogram of Forsythia suspensa leaves prepared by natural stacking fermentation in Comparative Example 1;

[0027] Figure 2 This is a high performance liquid chromatogram of the Forsythia tea prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Example 1: A fermentation preparation process for reducing the coldness of Forsythia tea, comprising the following steps:

[0030] Step 1: Preliminary treatment of the Forsythia suspensa leaves, including screening, weighing, washing, high temperature softening, rolling and high temperature steam sterilization;

[0031] (1) Screening of Forsythia suspensa leaves: Pick the stems of dry Forsythia suspensa leaves cleanly and select leaves of uniform size and without insect pests;

[0032] (2) Weighing of raw material leaves of Forsythia suspensa: weigh 15 g of dried Forsythia suspensa leaves;

[0033] (3) Clean the weighed Forsythia suspensa leaves;

[0034] (4) High temperature softening: Put the cleaned Forsythia leaves into a steamer and steam them to fully soften them. After the steaming is completed, remove the clear water on the surface;

[0035] (5) rolling and twisting: spraying a protective liquid on the softened Forsythia suspensa leaves, wherein the protective liquid is a mixture of 1.5 wt % citric acid and 1 wt % sodium bicarbonate, and the spraying amount is 30 mL per kilogram of Forsythia suspensa leaves; then rolling and twisting the Forsythia suspensa leaves repeatedly according to the method of “light 2 min-heavy 1 min-light 2 min”, so that the leaves are curled, the tea juice overflows, and the juice does not drip when the leaves are held in a ball;

[0036] (6) High-temperature steam sterilization: Place the rolled Forsythia suspensa leaves in a food-grade culture dish, wrap them with newspaper, and sterilize them at 121°C for 20 minutes.

[0037] Step 2: Activate and expand the culture of Lactobacillus plantarum and Lactobacillus bulgaricus, then centrifuge to collect the colony precipitate and use sterile saline to adjust the bacterial solution concentration to 5×10 6 cfu / mL, and then compounded at a volume ratio of 1:2 to obtain a mixed strain, added the mixed strain to the treated Forsythia suspensa leaves at an inoculation rate of 4% (v / w), placed in a fermentation box, and set the fermentation temperature to 30°C and the fermentation time to 20h for solid-state fermentation;

[0038] The preparation of Lactobacillus plantarum includes the following steps: inoculating the freeze-dried powder of Lactobacillus plantarum into the sterilized MRS liquid culture medium, placing it in a constant temperature shaker, setting the temperature to 35°C and the rotation speed to 100 rpm, culturing for 20 hours for the first activation, then inoculating it into a 250mL triangular flask containing 100mL of new culture medium with an inoculum amount of 3% (v / w), culturing it at 35°C for 20 hours, and finally storing it in a 4°C refrigerator for later use.

[0039] The preparation of German Lactobacillus bulgaricus comprises the following steps: inoculating freeze-dried powder of German Lactobacillus bulgaricus into sterilized MRS liquid culture medium, placing the mixture in a constant temperature shaker with a temperature of 37 DEG C and a rotation speed of 100 rpm for culturing for 24 hours for the first activation, then inoculating the mixture into a 250 mL triangular flask containing 100 mL of new culture medium with an inoculum amount of 4% (v / w), culturing the mixture at 37 DEG C for 20 hours, and finally storing the mixture in a refrigerator at 4 DEG C for standby use.

[0040] Step 3: under sterile conditions, add the fermentation strain of Pichia guilliermong BC 621 at an inoculation rate of 6% (v / w) to the Forsythia suspensa leaves after solid-state fermentation, put them in a fermentation box, set the fermentation temperature at 32° C. and the fermentation time for 60 h for secondary fermentation;

[0041] The preparation of the fermentation strain of Pichia guilleris BC 621 includes the following steps: activating the BC 621 strain on the wort medium and then inoculating it into the slant culture medium, culturing it at a constant temperature of 27°C for 20 hours, then washing the slant culture lawn with sterile water to prepare a uniform bacterial suspension; then diluting the bacterial suspension with sterile water to an OD 600 of 0.602, inoculating it into a 100 mL shaking flask containing 50 mL of liquid culture medium at an inoculation rate of 10% (v / w), and culturing it at 27°C for 24 hours.

[0042] Step 4: Dry the Forsythia suspensa leaves after secondary fermentation until the water content is below 6%.

[0043] Example 2: A fermentation preparation process for reducing the coldness of Forsythia tea, comprising the following steps:

[0044] Step 1: Preliminary treatment of the Forsythia suspensa leaves, including screening, weighing, washing, high temperature softening, rolling and high temperature steam sterilization;

[0045] (1) Screening of Forsythia suspensa leaves: Pick the stems of dry Forsythia suspensa leaves cleanly and select leaves of uniform size and without insect pests;

[0046] (2) Weighing of raw material leaves of Forsythia suspensa: weigh 10 g of dry Forsythia suspensa leaves;

[0047] (3) Clean the weighed Forsythia suspensa leaves;

[0048] (4) High temperature softening: Put the cleaned Forsythia leaves into a steamer and steam them to fully soften them. After the steaming is completed, remove the clear water on the surface;

[0049] (5) rolling and twisting: spraying a protective liquid on the softened Forsythia suspensa leaves, wherein the protective liquid is a mixture of 3 wt % citric acid and 0.8 wt % sodium bicarbonate, and the spraying amount is 50 mL per kilogram of Forsythia suspensa leaves; then rolling and twisting the Forsythia suspensa leaves repeatedly according to the method of "light 2 min-heavy 1 min-light 2 min" until the leaves are curled, the tea juice overflows, and the juice does not drip when the leaves are held in a ball;

[0050] (6) High-temperature steam sterilization: Place the rolled Forsythia suspensa leaves in a food-grade culture dish, wrap them with newspaper, and sterilize them at 121°C for 40 minutes.

[0051] Step 2: Activate and expand the culture of Lactobacillus plantarum and Lactobacillus bulgaricus, then centrifuge to collect the colony precipitate and use sterile saline to adjust the bacterial solution concentration to 6×10 6 cfu / mL, and then compounded at a volume ratio of 1:3 to obtain a mixed strain, added the mixed strain to the treated Forsythia suspensa leaves at an inoculation rate of 2% (v / w), placed in a fermentation box, and set the fermentation temperature to 28°C and the fermentation time to 18 h for solid-state fermentation;

[0052] The preparation of Lactobacillus plantarum includes the following steps: inoculating the freeze-dried powder of Lactobacillus plantarum into the sterilized MRS liquid culture medium, placing it in a constant temperature shaker, setting the temperature to 35°C and the rotation speed to 120rpm, culturing for 24 hours for the first activation, then inoculating it into a 250mL conical flask containing 100mL of new culture medium with an inoculum amount of 6% (v / w), culturing it at 35°C for 22 hours, and finally storing it in a 4°C refrigerator for later use.

[0053] The preparation of German Lactobacillus bulgaricus comprises the following steps: inoculating freeze-dried powder of German Lactobacillus bulgaricus into sterilized MRS liquid culture medium, placing the mixture in a constant temperature shaker set at 37 DEG C and 160 rpm for culturing for 23 hours for first activation, then inoculating the mixture into a 250 mL triangular flask containing 100 mL of new culture medium at a 5% (v / w) inoculation amount, culturing the mixture at 37 DEG C for 24 hours, and finally storing the mixture in a 4 DEG C refrigerator for standby use.

[0054] Step 3: under sterile conditions, adding the fermentation strain of Pichia guilliermong BC 621 at an inoculation rate of 4% (v / w) to the Forsythia suspensa leaves after solid-state fermentation, placing the leaves in a fermentation box, setting the fermentation temperature at 30° C. and the fermentation time for 48 h for secondary fermentation;

[0055] The preparation of the fermentation strain of Pichia guilleris BC 621 includes the following steps: activating the BC 621 strain on the wort medium and then inoculating it into the slant culture medium, culturing it at a constant temperature of 28°C for 24 hours, then washing the slant culture lawn with sterile water to prepare a uniform bacterial suspension; then diluting the bacterial suspension with sterile water to an OD 600 of 0.6, inoculating it into a 100 mL shaking flask containing 50 mL of liquid culture medium at an inoculum amount of 10% (v / w), and culturing it at 28°C for 22 hours.

[0056] Step 4: Dry the Forsythia suspensa leaves after secondary fermentation until the water content is below 6%.

[0057] Example 3: A fermentation preparation process for reducing the coldness of Forsythia tea, comprising the following steps:

[0058] Step 1: Preliminary treatment of the Forsythia suspensa leaves, including screening, weighing, washing, high temperature softening, rolling and high temperature steam sterilization;

[0059] (1) Screening of Forsythia suspensa leaves: Pick the stems of dry Forsythia suspensa leaves cleanly and select leaves of uniform size and without insect pests;

[0060] (2) Weighing of raw material leaves of Forsythia suspensa: weigh 20 g of dry Forsythia suspensa leaves;

[0061] (3) Clean the weighed Forsythia suspensa leaves;

[0062] (4) High temperature softening: Put the cleaned Forsythia leaves into a steamer and steam them to fully soften them. After the steaming is completed, remove the clear water on the surface;

[0063] (5) rolling and twisting: spraying a protective liquid on the softened Forsythia suspensa leaves, wherein the protective liquid is a mixture of 2 wt % citric acid and 0.5 wt % sodium bicarbonate, and the spraying amount is 40 mL per kilogram of Forsythia suspensa leaves; then rolling and twisting the Forsythia suspensa leaves repeatedly according to the method of "light 2 min-heavy 1 min-light 2 min" until the leaves are curled, the tea juice overflows, and the juice does not drip when the leaves are held in a ball;

[0064] (6) High-temperature steam sterilization: Place the rolled Forsythia suspensa leaves in a food-grade culture dish, wrap them with newspaper, and sterilize them at 121°C for 30 minutes.

[0065] Step 2: Activate and expand the culture of Lactobacillus plantarum and Lactobacillus bulgaricus, then centrifuge to collect the colony precipitate and use sterile saline to adjust the bacterial solution concentration to 5.5×10 6 cfu / mL, and then compounded at a volume ratio of 1:1 to obtain a mixed strain, added the mixed strain to the treated Forsythia suspensa leaves at an inoculation rate of 6% (v / w), placed in a fermentation box, and set the fermentation temperature at 32°C and the fermentation time for 22 h for solid-state fermentation;

[0066] The preparation of Lactobacillus plantarum includes the following steps: inoculating the freeze-dried powder of Lactobacillus plantarum into the sterilized MRS liquid culture medium, placing it in a constant temperature shaker, setting the temperature to 35°C and the rotation speed to 160rpm, culturing for 23 hours for the first activation, then inoculating it into a 250mL conical flask containing 100mL of new culture medium with an inoculum amount of 5% (v / w), culturing it at 35°C for 24 hours, and finally storing it in a 4°C refrigerator for later use.

[0067] The preparation of German Lactobacillus bulgaricus comprises the following steps: inoculating freeze-dried powder of German Lactobacillus bulgaricus into a sterilized MRS liquid culture medium, placing the mixture in a constant temperature shaker set at 37°C and a rotation speed of 120 rpm for culturing for 20 hours for the first activation, then inoculating the mixture into a 250 mL triangular flask containing 100 mL of new culture medium at an inoculation amount of 8% (v / w), culturing the mixture at 37°C for 20 hours, and finally storing the mixture in a refrigerator at 4°C for standby use.

[0068] Step 3: under sterile conditions, adding the fermentation strain of Pichia guilliermong BC 621 at an inoculation rate of 8% (v / w) to the Forsythia suspensa leaves after solid-state fermentation, placing the leaves in a fermentation box, setting the fermentation temperature at 34° C. and the fermentation time for 72 h for secondary fermentation;

[0069] The preparation of the fermentation strain of Pichia guillermongi BC 621 includes the following steps: activating the BC 621 strain on the wort medium and then inoculating it into the slant culture medium, culturing it at a constant temperature of 29°C for 23 hours, then washing the slant culture lawn with sterile water to prepare a uniform bacterial suspension; then diluting the bacterial suspension with sterile water to an OD 600 of 0.598, inoculating it into a 100 mL shaking flask containing 50 mL of liquid culture medium at an inoculation rate of 10% (v / w), and culturing it at 29°C for 20 hours.

[0070] Step 4: Dry the Forsythia suspensa leaves after secondary fermentation until the water content is below 6%.

[0071] Example 4: A fermentation preparation process for reducing the coldness of Forsythia tea, comprising the following steps:

[0072] Step 1: Preliminary treatment of the Forsythia suspensa leaves, including screening, weighing, washing, high temperature softening, rolling and high temperature steam sterilization;

[0073] (1) Screening of Forsythia suspensa leaves: Pick the stems of dry Forsythia suspensa leaves cleanly and select leaves of uniform size and without insect pests;

[0074] (2) Weighing of raw material leaves of Forsythia suspensa: weigh 18 g of dried Forsythia suspensa leaves;

[0075] (3) Clean the weighed Forsythia suspensa leaves;

[0076] (4) High temperature softening: Put the cleaned Forsythia leaves into a steamer and steam them to fully soften them. After the steaming is completed, remove the clear water on the surface;

[0077] (5) rolling and twisting: spraying a protective liquid on the softened Forsythia suspensa leaves, wherein the protective liquid is a mixture of 2.5 wt % citric acid and 1 wt % sodium bicarbonate, and the spraying amount is 35 mL per kilogram of Forsythia suspensa leaves; then rolling and twisting the Forsythia suspensa leaves repeatedly according to the method of "light 2 min-heavy 1 min-light 2 min" until the leaves are curled, the tea juice overflows, and the juice does not drip when the leaves are held in a ball;

[0078] (6) High-temperature steam sterilization: Place the rolled Forsythia suspensa leaves in a food-grade culture dish, wrap them with newspaper, and sterilize them at 121°C for 40 minutes.

[0079] Step 2: Activate and expand the culture of Lactobacillus plantarum and Lactobacillus bulgaricus, then centrifuge to collect the colony precipitate and use sterile saline to adjust the bacterial solution concentration to 6×10 6 cfu / mL, and then compounded at a volume ratio of 2:1 to obtain a mixed strain, added the mixed strain to the treated Forsythia suspensa leaves at an inoculation rate of 8% (v / w), placed in a fermentation box, and set the fermentation temperature at 37°C and the fermentation time for 24 h for solid-state fermentation;

[0080] The preparation of Lactobacillus plantarum includes the following steps: inoculating the freeze-dried powder of Lactobacillus plantarum into the sterilized MRS liquid culture medium, placing it in a constant temperature shaker, setting the temperature to 35°C and the rotation speed to 140rpm, culturing for 24 hours for the first activation, then inoculating it into a 250mL triangular flask containing 100mL of new culture medium with an inoculum amount of 4% (v / w), culturing it at 35°C for 24 hours, and finally storing it in a 4°C refrigerator for later use.

[0081] The preparation of German Lactobacillus bulgaricus comprises the following steps: inoculating freeze-dried powder of German Lactobacillus bulgaricus into sterilized MRS liquid culture medium, placing the mixture in a constant temperature shaker set at 37°C and 150rpm for culturing for 21h for first activation, then inoculating the mixture into a 250mL triangular flask containing 100mL new culture medium at a 7% (v / w) inoculation amount, culturing the mixture at 37°C for 20h, and finally storing the mixture in a 4°C refrigerator for standby use.

[0082] Step 3: under sterile conditions, adding the fermentation strain of Pichia guilliermong BC 621 at an inoculation rate of 10% (v / w) to the Forsythia suspensa leaves after solid-state fermentation, placing the leaves in a fermentation box, setting the fermentation temperature at 35° C. and the fermentation time for 72 h for secondary fermentation;

[0083] The preparation of the fermentation strain of Pichia guilleris BC 621 includes the following steps: activating the BC 621 strain on the wort medium and then inoculating it into the slant culture medium, culturing it at a constant temperature of 28°C for 20 hours, then washing the slant culture lawn with sterile water to prepare a uniform bacterial suspension; then diluting the bacterial suspension with sterile water to an OD 600 of 0.6, inoculating it into a 100 mL shaking flask containing 50 mL of liquid culture medium at an inoculation rate of 10% (v / w), and culturing it at 28°C for 24 hours.

[0084] Step 4: Dry the Forsythia suspensa leaves after secondary fermentation until the water content is below 6%.

[0085] Example 5: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0086] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, Lactobacillus plantarum and Lactobacillus bulgaricus are compounded in a volume ratio of 2:1 to obtain a mixed strain.

[0087] Example 6: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0088] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, Lactobacillus plantarum and Lactobacillus bulgaricus are compounded in a volume ratio of 3:2 to obtain a mixed strain.

[0089] Example 7: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0090] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, Lactobacillus plantarum and Lactobacillus bulgaricus are compounded in a volume ratio of 1:1 to obtain a mixed strain.

[0091] Example 8: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0092] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, Lactobacillus plantarum and Lactobacillus bulgaricus are compounded in a volume ratio of 2:3 to obtain a mixed strain.

[0093] Example 9: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0094] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, Lactobacillus plantarum and Lactobacillus bulgaricus are compounded in a volume ratio of 3:1 to obtain a mixed strain.

[0095] Example 10: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0096] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, Lactobacillus plantarum and Lactobacillus bulgaricus are compounded in a volume ratio of 1:3 to obtain a mixed strain.

[0097] Example 11: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0098] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, the mixed bacteria are added to the treated Forsythia suspensa leaves at an inoculation rate of 2% (v / w).

[0099] Example 12: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0100] The preparation method of this embodiment is different from that of embodiment 1 only in that in this embodiment, the mixed bacteria are added to the treated Forsythia suspensa leaves at an inoculation rate of 6% (v / w).

[0101] Example 13: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0102] The preparation method of this embodiment is different from that of embodiment 1 only in that in this embodiment, the mixed bacteria are added to the treated Forsythia suspensa leaves at an inoculation rate of 8% (v / w).

[0103] Example 14: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0104] The preparation method of this embodiment is different from that of embodiment 1 only in that in this embodiment, the mixed bacteria are added to the treated Forsythia suspensa leaves at an inoculation rate of 10% (v / w).

[0105] Example 15: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0106] The preparation method of this embodiment is different from that of embodiment 1 only in that: in this embodiment, the fermentation strain of Pichia guilliermong BC621 is added to the Forsythia suspensa leaves after solid-state fermentation at an inoculation rate of 4% (v / w).

[0107] Example 16: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0108] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, the fermentation strain of Pichia guilliermong BC621 is added to the Forsythia suspensa leaves after solid-state fermentation at an inoculation rate of 8% (v / w).

[0109] Example 17: A fermentation preparation process for reducing the coldness of Forsythia tea:

[0110] The preparation method of this embodiment is different from that of Embodiment 1 only in that: in this embodiment, the fermentation strain of Pichia guilliermong BC621 is added to the Forsythia suspensa leaves after solid-state fermentation at an inoculation rate of 10% (v / w).

[0111] Comparative Example 1:

[0112] A cascade extraction process for active ingredients of edible fungi:

[0113] Step 1: Pick the branches of the dry Forsythia leaves clean, select the leaves of uniform size and without insect pests, weigh 15g of dry Forsythia leaves and wash them clean;

[0114] Step 2: Put the cleaned forsythia leaves into a steamer and steam them until they are fully softened. After steaming, remove the clear water on the surface;

[0115] Step 3: spraying the softened Forsythia suspensa leaves with a protective liquid, wherein the protective liquid is a mixture of 1.5wt% citric acid and 1wt% sodium bicarbonate, and the spraying amount is 30mL per kilogram of Forsythia suspensa leaves; then repeatedly kneading the Forsythia suspensa leaves according to "light 2min-heavy 1min-light 2min" to make the leaves curl, the tea juice overflows, and the juice does not drip when the leaves are held in a ball;

[0116] Step 4: Put the processed Forsythia suspensa leaves into a fermentation box, set the fermentation temperature to 30° C. and the fermentation time to 20 hours for fermentation. After the fermentation is completed, dry the Forsythia suspensa leaves to a water content of less than 6%.

[0117] Experimental part:

[0118] According to the method in the standard of GB / T 23776-2018 "Tea Sensory Evaluation Method", 1g of each fermented tea in Example 1, Example 5-17 and Comparative Example 1 was taken and placed in an evaluation cup, 50mL of boiling water was added, and the tea was poured into the evaluation cup at a constant speed in the same brewing order, followed by a second brewing. After soaking for 5 minutes, the tea was drained, and several evaluators were randomly invited to evaluate the soup color, aroma, taste and leaf bottom of the first drained tea, and then the soup color, aroma, taste and leaf bottom of the second drained tea were evaluated in turn. The evaluation results were judged by the soup color of the first brewing tea soup, and then the appearance, aroma, taste and leaf bottom were judged by the second brewing results. After comprehensive evaluation, the Forsythia tea prepared in Example 1, i.e., Lactobacillus plantarum and Lactobacillus bulgaricus were compounded in a volume ratio of 1:2 to obtain a mixed strain, and the mixed strain was added to the treated Forsythia leaves in an inoculation amount of 6% by volume, and placed in a fermentation box, and the fermentation temperature was set to 30°C and the fermentation time was 20h for solid-state fermentation; under sterile conditions, the fermentation strain of Pichia guilliermong BC 621 was added to the Forsythia leaves after solid-state fermentation in an inoculation amount of 6% (v / w), and placed in a fermentation box, and the fermentation temperature was set to 32°C and the fermentation time was set to 60h for secondary fermentation. The sensory evaluation of the prepared Forsythia tea was the best, with a red, thick and bright soup color; a strong and firm appearance, beautiful shape, oily color, uniformity, and good clarity; a pure aroma, no impurities, and a high and refreshing aroma; a mellow taste with a sweet and refreshing aftertaste; and tender, uniform leaf bottoms with many buds, bright, and uniform.

[0119] 1 g of each of the forsythia tea prepared in Examples 1, 5, 6, 10-13, 15-17 and Comparative Example 1 was taken, and the cold and cool characteristic components were determined by high performance liquid chromatography. The results of the proportion of each cold and cool characteristic component are shown in Table 1, wherein the high performance liquid chromatograms of Example 1 and Comparative Example 1 are shown in Table 1. Figure 1 , 2 As shown in the figure, the first peak is the characteristic peak of rutin, the second peak is forsythiaside A, the third peak is forsythiaside, and the fourth peak is forsythiaside. Figure 1 ,2 It can be seen from the comparison and the data in Table 1 that the active ingredients with cold properties in the Forsythia tea obtained by the fermentation preparation process of the present invention are significantly reduced. Therefore, it is also suitable for people with weak spleen and stomach and weak constitution to drink, thereby expanding the audience population.

[0120] In Table 1, it can be seen from the data of Examples 1, 5, 6, and 10 that the different composite ratios of plant lactobacillus and German lactobacillus bulgaricus have a certain influence on the fermentation of Forsythia tea. In Example 1, when the composite ratio of plant lactobacillus and German lactobacillus bulgaricus is 1:2, the cold and cool characteristic component content of fermented Forsythia tea is the least. In Examples 5, 6, and 10, when the proportion of German lactobacillus bulgaricus is too small or too large, the coordination effect of the two strains is not good enough, and the cold and cool characteristic component of fermented Forsythia tea is significantly different from that of Example 1. Therefore, by optimizing the strain combination, the fermentation efficiency can be significantly improved, and the cold and cool characteristic component of Forsythia tea can be reduced. The composite strain can produce more types of metabolites, improve the quality and diversity of the product, and the strains can adapt and coordinate with each other, and jointly cope with the changes in environmental conditions, and the composite strain has stronger environmental adaptability and stability.

[0121] In Table 1, it can be seen from the data of Examples 1, 11-13 that the inoculation amount of the composite strain of plant lactobacillus and German Lactobacillus bulgaricus also has a certain influence on the fermentation of Forsythia tea. In Example 1, when the inoculation amount is 4%, the cold characteristic component content of the fermented Forsythia tea is the least. When the fermentation inoculation amount is large, the strain is too dense and the dissolved oxygen is insufficient, which further affects the synthesis of the product and too many strains will produce a large amount of metabolic waste; while a small inoculation amount will lead to an extension of the fermentation cycle and a small amount of strains, which affects the synchronous growth and the stable synthesis of the product. Therefore, both situations where the inoculation amount is too large or too small will affect the cold characteristic components of the fermented Forsythia tea.

[0122] In Table 1, it can be seen from the data of Examples 1 and 15-17 that the amount of the strain inoculation of Pichia guilliermong BC 621 will affect the strain's tolerance to pH and also have a certain effect on the fermentation of Forsythia tea. In Example 1, when the strain inoculation amount is 6%, the tolerance effect is good, and the content of the cold and cool characteristic components of the fermented Forsythia tea is the lowest. When the inoculation amount is less than 6%, for example, when the inoculation amount is 4%, because the number of strains is too small, Forsythia tea is not tolerated, resulting in poor fermentation effect of Forsythia tea. However, when the inoculation amount is greater than 6%, for example, when the inoculation amount is 8%, too much inoculation will cause the strain to be too dense, resulting in a large amount of metabolites, affecting the fermentation effect. Therefore, by adding an appropriate amount of strains to ferment Forsythia tea, the fermentation efficiency can be improved, the taste and aroma of tea can be improved, and the content of cold and cool characteristic components in Forsythia tea can be effectively reduced.

[0123] Table 1 Comparison of physical and chemical indicators

[0124] sample Rutin(%) Forsythiaside A(%) Forsythiaside(%) Forsythiaside(%) Example 1 0.28 0.33 0.29 1.01 Example 5 0.30 0.47 0.46 1.17 Example 6 0.35 0.47 0.32 1.08 Example 10 0.39 0.48 0.43 1.16 Embodiment 11 0.33 0.46 0.44 1.13 Example 12 0.29 0.41 0.40 1.23 Example 13 0.43 0.52 0.38 1.25 Embodiment 15 0.26 0.43 0.41 1.13 Example 16 0.28 0.45 0.43 1.23 Embodiment 17 0.24 0.47 0.39 1.17 Comparative Example 1 0.58 0.67 0.54 1.34

Claims

1. A fermentation preparation process for reducing the coldness of Forsythia tea, characterized in that: The steps include: Step 1: Preliminary treatment of the Forsythia suspensa leaves, including screening, weighing, washing, high temperature softening, rolling and high temperature steam sterilization; Step 2: Compounding Lactobacillus plantarum and Lactobacillus bulgaricus in a volume ratio of (1-3):(3-1) to obtain a mixed strain, adding the mixed strain to the treated Forsythia suspensa leaves at an inoculum amount of 2-8% (v / w), placing the mixed strain in a fermentation box, setting the fermentation temperature at 28-37° C. and the fermentation time at 18-24 h for solid-state fermentation; Step 3: under sterile conditions, adding the fermentation strain of Pichia guilliermong BC 621 at an inoculation rate of 4-10% (v / w) to the Forsythia suspensa leaves after solid-state fermentation, placing the leaves in a fermentation box, setting the fermentation temperature at 30-35° C. and the fermentation time at 48-72 h for secondary fermentation; Step 4: Dry the Forsythia suspensa leaves after secondary fermentation until the water content is below 6%.

2. The fermentation preparation process for reducing the cold property of Forsythia tea according to claim 1, characterized in that: Step 1 The specific operation of the early treatment of forsythia leaves includes the following steps: (1) Screening of Forsythia suspensa leaves: Pick the stems of dry Forsythia suspensa leaves cleanly and select leaves of uniform size and without insect pests; (2) Weighing the raw material leaves of Forsythia suspensa: weigh 10-20 g of dry Forsythia suspensa leaves; (3) Clean the weighed Forsythia suspensa leaves; (4) High temperature softening: Put the cleaned Forsythia leaves into a steamer and steam them to fully soften them. After the steaming is completed, remove the clear water on the surface; (5) Rolling: Spraying the softened Forsythia suspensa leaves with a protective liquid, wherein the protective liquid is a mixture of 1.5-3wt% citric acid and 0.5-1wt% sodium bicarbonate, and the spraying amount is 30-50mL per kilogram of Forsythia suspensa leaves; then rolling the Forsythia suspensa leaves repeatedly according to the principle of "light 2min-heavy 1min-light 2min" until the leaves are curled, the tea juice overflows, and the juice does not drip when the leaves are held in a ball; (6) High-temperature steam sterilization: Place the rolled Forsythia suspensa leaves in a food-grade culture dish, wrap them with newspaper, and sterilize them at 121°C for 20-40 minutes.

3. The fermentation preparation process for reducing the cold property of Forsythia tea according to claim 1, characterized in that: The preparation of the plant lactobacillus in step 2 comprises the following steps: inoculating the plant lactobacillus lyophilized powder into the sterilized MRS liquid culture medium, placing it in a constant temperature shaker, setting the temperature to 35°C, the rotation speed to 100-160rpm, culturing for 20-24h for the first activation, then inoculating it into a 250mL triangular flask containing 100mL of new culture medium with an inoculum amount of 3-6% (v / w), culturing it at 35°C for 20-24h, and finally storing it in a 4°C refrigerator for standby use.

4. The fermentation preparation process for reducing the cold property of Forsythia tea according to claim 3, characterized in that: The preparation of the German Lactobacillus bulgaricus described in step 2 comprises the following steps: inoculating the German Lactobacillus bulgaricus freeze-dried powder into the sterilized MRS liquid culture medium, placing it in a constant temperature shaker set at a temperature of 37° C. and a rotation speed of 100-160 rpm for culturing for 20-24 hours for the first activation, then inoculating it into a 250 mL triangular flask containing 100 mL of new culture medium with an inoculum amount of 4-8% (v / w), culturing it at 37° C. for 20-24 hours, and finally storing it in a 4° C. refrigerator for standby use.

5. The fermentation preparation process for reducing the cold property of Forsythia tea according to claim 4, characterized in that: The specific operation of compounding the plant lactobacillus and the German Lactobacillus bulgaricus described in step 2 comprises the following steps: (1) activating and expanding the culture of Lactobacillus plantarum and Lactobacillus bulgaricus; (2) The activated and expanded Lactobacillus plantarum and Lactobacillus bulgaricus were centrifuged, and the colony precipitates were collected and the bacterial solution concentration was adjusted to 5-6×10 6 cfu / mL; (3) Compounding Lactobacillus plantarum and Lactobacillus bulgaricus in a volume ratio of (1-3):(3-1).

6. The fermentation preparation process for reducing the cold property of Forsythia tea according to claim 1, characterized in that: Step 3: The preparation of the fermentation strain of Pichia quaternaria BC 621 includes the following steps: activating the BC 621 strain on the wort medium and then inoculating it into the slant culture medium, culturing it at a constant temperature of 28±1°C for 20-24h, then washing the slant culture lawn with sterile water to prepare a uniform bacterial suspension; then diluting the bacterial suspension with sterile water to an OD 600 of 0.600±0.002, inoculating it into a 100mL shake flask containing 50mL of liquid culture medium at an inoculum amount of 10% (v / w), and culturing it at 28±1°C for 20-24h.

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