Method for producing medicinal ethanol through fermentation of waste molasses

Abstract

The invention relates to the field of pharmaceutical chemicals, in particular to a method for producing medicinal ethanol through fermentation of waste molasses. The method for producing the medicinal ethanol by fermenting the waste molasses comprises the following steps: adding a compound enzyme preparation into cane molasses, and treating to obtain enzyme treated molasses; inoculating wine-making active dry yeast for fermentation to obtain cooked mash; and carrying out crude distillation, dealdehyding and rectification on the prepared cooked mash to obtain the medicinal ethanol. The method for producing the medicinal ethanol through fermentation of the waste molasses is simple in technological process, the prepared fermentation liquor is high in alcoholic strength, the production efficiency is greatly improved, meanwhile, the use amount of corrosive strong acid is reduced, and the effects of saving energy, improving efficiency and reducing emission can be achieved for enterprises.

Description

Technical Field

[0001] The invention relates to the field of pharmaceutical chemicals, and in particular to a method for producing medicinal ethanol by fermenting waste molasses. Background Art

[0002] Ethanol is a colorless, transparent liquid with a special aroma. It is volatile, has a lower density than water, and can be miscible with water in any ratio. As a commonly used solvent, ethanol can dissolve many inorganic and organic substances, so ethanol is often used to extract medicinal ingredients from plants. In the production of pharmaceutical preparations, ethanol can also be used as a wetting agent, solvent, preservative, etc., and is widely used in various Chinese and Western medicine preparations. At the same time, ethanol also has the effect of sterilization and disinfection. 75% medical disinfectant alcohol is prepared with medicinal ethanol.

[0003] Sugarcane molasses is a by-product of the sugar industry. It is the thick liquid left after the sugar industry heats, neutralizes, precipitates, filters, concentrates, and crystallizes the squeezed sugarcane juice to make sugar. It is commonly known as molasses. Sugarcane molasses is rich in sucrose and reducing sugars and is one of the most economical raw materials for fermenting alcohol. Traditional molasses fermentation alcohol suppresses bacteria by adding sulfuric acid to adjust the pH value, which can easily cause equipment corrosion and environmental pollution. In recent years, the use of complex enzyme preparations for molasses alcohol fermentation has become a research hotspot in the current field.

[0004] The Chinese invention patent (application number: 202410148482.9) "A method for producing alcohol by fermentation using a high-biological enzyme activity antibacterial agent" discloses a high-biological enzyme activity antibacterial agent prepared by optimizing the process of nisin and biological enzyme preparations pectinase and cellulase. It is applied to alcohol fermentation and has good antibacterial properties. At the same time, the fermentation alcohol content can reach up to 16%. This research can reduce the content of residual reducing sugars and reduce the use of sulfuric acid or antibiotics in the alcohol fermentation process, which is beneficial for alcohol production enterprises to achieve efficiency improvement and emission reduction. However, the application still has the following shortcomings: (1) The fermentation alcohol content is not high; (2) The production cost is relatively high.

[0005] In order to solve the above problems, the present invention provides a method for producing medicinal ethanol by fermenting waste molasses, aiming to further improve the production efficiency of the enterprise and increase the fermentation alcohol content of sugarcane molasses. Summary of the invention

[0006] The object of the present invention is to provide a method for producing medicinal ethanol by fermenting waste molasses.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0008] The method for producing medicinal ethanol by fermenting waste molasses of the present invention comprises the following steps:

[0009] S1: adding a composite enzyme preparation consisting of lysozyme, pectinase, protease and cellulase to sugarcane molasses, mixing and treating at a temperature of 25 to 30° C. for 60 to 120 minutes to obtain enzyme-treated molasses;

[0010] S2: dilute the enzyme-treated molasses obtained in the above step with distilled water to 20-35 BX, add dilute sulfuric acid to adjust the pH to 4-5, add nutrient salt and stir evenly, add 1‰-3‰ of active dry yeast for brewing with sugar cane molasses, and add 0.1‰-0.5‰ of urea with sugar cane molasses, mix evenly, and ferment at 28-36°C for 48-96h to obtain cooked mash;

[0011] S3: The cooked mash obtained in the above steps is subjected to crude distillation, dealdehyde removal and rectification to obtain medicinal ethanol.

[0012] Preferably, in the method for producing medicinal ethanol by fermenting waste molasses of the present invention, the mixing treatment conditions in step S1 are: mixing treatment at a temperature of 28° C. for 90 minutes.

[0013] In the method for producing medicinal ethanol by fermenting waste molasses of the present invention, the amount of the composite enzyme preparation added in step S1 is 0.3-0.5% of the amount of sugarcane molasses, and the composite enzyme preparation consists of 25%-35% lysozyme, 20%-30% pectinase, 10%-20% protease and 25%-35% cellulase.

[0014] Preferably, in the method for producing medicinal ethanol by fermenting waste molasses of the present invention, the amount of the composite enzyme preparation added in step S1 is 0.4% of the amount of sugarcane molasses, and the composite enzyme preparation consists of 30% lysozyme, 25% pectinase, 15% protease and 30% cellulase.

[0015] In the method for producing medicinal ethanol by fermenting waste molasses of the present invention, the nutrient salt in step S2 is composed of ammonium sulfate, ammonium hydrogen phosphate and calcium chloride in a mass ratio of 2:2:1, and the added amount is 0.5% to 1% of the amount of sugarcane molasses.

[0016] Preferably, in the method for producing medicinal ethanol by fermenting waste molasses of the present invention, the inoculation amount of the active dry yeast for brewing in step S2 is 2‰ of the amount of sugarcane molasses, the amount of urea added is 0.3‰ of the amount of sugarcane molasses, and the fermentation condition is fermentation at 32%°C for 72 hours.

[0017] In the method for producing medicinal ethanol by fermenting waste molasses described in the present invention, the crude distillation in step S3 is to evaporate the cooked mash and steam at a temperature of 60 to 78°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 1 to 3:1; the dealdehydeation is to evaporate the cooked mash and steam at a temperature of 78 to 100°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 3 to 7:1.

[0018] Preferably, in the method for producing medicinal ethanol by fermenting waste molasses according to the present invention, the crude distillation in step S3 is to evaporate the cooked mash and steam at a temperature of 70-75°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 2-3:1; the dealdehydeation is to evaporate the cooked mash and steam at a temperature of 90-100°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 5-7:1.

[0019] Further preferably, in the method for producing medicinal ethanol by fermenting waste molasses according to the present invention, the crude distillation in step S3 is to evaporate the cooked mash and steam at a temperature of 75°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 3:1; the dealdehydeation is to evaporate the cooked mash and steam at a temperature of 95°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 6:1.

[0020] In the method for producing medicinal ethanol by fermenting waste molasses of the present invention, the treatment temperature of the distillation in step S3 is 65°C.

[0021] Beneficial effects of the present invention:

[0022] The invention provides a method for producing medicinal ethanol by fermenting waste molasses. The method has a simple process flow, and the obtained fermentation liquid has high alcohol content, which greatly improves the production efficiency and reduces the usage of corrosive strong acid, thereby achieving the effects of energy saving, efficiency improvement and emission reduction for enterprises.

[0023] The present invention determines the optimal parameters of the fermentation process by investigating the fermentation temperature and fermentation time: the fermentation temperature is 32° C., the fermentation time is 72 h, and the alcohol content of the fermentation liquid after the fermentation is completed can reach up to 17.5%, which can greatly improve the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a process flow chart. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is described in detail below in conjunction with specific embodiments. The following embodiments are only used for explanation and illustration, and do not constitute a limitation on the technical solution of the present invention.

[0026] Example 1

[0027] A method for producing medicinal ethanol by fermenting waste molasses, the steps are as follows:

[0028] S1: adding a composite enzyme preparation consisting of 30% lysozyme, 25% pectinase, 15% protease and 30% cellulase to sugarcane molasses at a rate of 0.4% of the amount of sugarcane molasses, mixing and treating at a temperature of 28° C. for 90 minutes to obtain enzyme-treated molasses;

[0029] S2: dilute the enzyme-treated molasses obtained in the above step to 30BX with distilled water, add dilute sulfuric acid to adjust the pH to 4.5, add 0.5% of sugarcane molasses and a nutrient salt consisting of ammonium sulfate, ammonium hydrogen phosphate and calcium chloride in a mass ratio of 2:2:1 and stir evenly, add 2‰ of active dry yeast for brewing using sugarcane molasses, and add 0.3‰ of urea using sugarcane molasses, mix evenly and ferment at 32°C for 72h to obtain a cooked mash;

[0030] S3: The cooked mash obtained in the above steps is subjected to crude distillation (temperature of 75°C, flow ratio of cooked mash to steam of 3:1), dealdehydeation (temperature of 95°C, flow ratio of cooked mash to steam of 6:1), and rectification (temperature of 65°C) to obtain medicinal ethanol.

[0031] Example 2

[0032] A method for producing medicinal ethanol by fermenting waste molasses, the steps are as follows:

[0033] S1: adding a composite enzyme preparation consisting of 25% lysozyme, 30% pectinase, 20% protease and 25% cellulase to sugarcane molasses at a rate of 0.3% of the amount of sugarcane molasses, mixing and treating for 120 minutes at a temperature of 25°C to obtain enzyme-treated molasses;

[0034] S2: dilute the enzyme-treated molasses obtained in the above step with distilled water to 34BX, add dilute sulfuric acid to adjust the pH to 4.5, add 0.5% of sugarcane molasses and a nutrient salt consisting of ammonium sulfate, ammonium hydrogen phosphate and calcium chloride in a mass ratio of 2:2:1 and stir evenly, add 2‰ of active dry yeast for brewing using sugarcane molasses, and add 0.3‰ of urea using sugarcane molasses, mix evenly, and ferment at 32.5°C for 72h to obtain a cooked mash;

[0035] S3: The cooked mash obtained in the above steps is subjected to crude distillation (temperature of 75°C, flow ratio of cooked mash to steam of 3:1), dealdehydeation (temperature of 95°C, flow ratio of cooked mash to steam of 6:1), and rectification (temperature of 65°C) to obtain medicinal ethanol.

[0036] Example 3

[0037] A method for producing medicinal ethanol by fermenting waste molasses, the steps are as follows:

[0038] S1: adding a composite enzyme preparation consisting of 35% lysozyme, 20% pectinase, 10% protease and 35°C cellulase to sugarcane molasses at a rate of 0.5% of the amount of sugarcane molasses, and mixing and treating at a temperature of 28°C for 90 minutes to obtain enzyme-treated molasses;

[0039] S2: dilute the enzyme-treated molasses obtained in the above step to 30BX with distilled water, add dilute sulfuric acid to adjust the pH to 4.5, add 0.4% of sugarcane molasses and a nutrient salt consisting of ammonium sulfate, ammonium hydrogen phosphate and calcium chloride in a mass ratio of 2:2:1 and stir evenly, add 3‰ of active dry yeast for brewing using sugarcane molasses, and add 0.5‰ of urea using sugarcane molasses, mix evenly and ferment at 33°C for 72h to obtain a cooked mash;

[0040] S3: The cooked mash obtained in the above steps is subjected to crude distillation (temperature of 70°C, flow ratio of cooked mash to steam of 2:1), remover (temperature of 90°C, flow ratio of cooked mash to steam of 7:1), and rectification (temperature of 65°C) to obtain medicinal ethanol.

[0041] In order to further verify the reliability of the present invention and screen out the best solution, the inventor conducted a series of experiments, as follows:

[0042] 1. Test methods

[0043] 1.1 Key points of the process

[0044] See the process flow Figure 1 , the operation points are as follows:

[0045] The compound enzyme preparation composed of 30% lysozyme, 25% pectinase, 15% protease and 30% cellulase was added to the sugarcane molasses at 0.4% of the amount of sugarcane molasses, and mixed and treated at a temperature of 28°C for 90 minutes to obtain enzyme-treated molasses;

[0046] The enzyme-treated molasses obtained in the above step is diluted to 30BX with distilled water, diluted sulfuric acid is added to adjust the pH to 4.5, 0.5% of the sugarcane molasses amount of nutrient salt consisting of ammonium sulfate, ammonium hydrogen phosphate, and calcium chloride in a mass ratio of 2:2:1 is added and stirred evenly, 2‰ of the sugarcane molasses amount of active dry yeast for brewing is added, and 0.3‰ of urea is added to the sugarcane molasses amount, and after mixing evenly, ferment at 32.5°C for 72h to obtain a cooked mash;

[0047] The cooked mash obtained in the above steps is subjected to crude distillation (temperature of 75°C, flow ratio of cooked mash to steam of 3:1), dealdehydeation (temperature of 95°C, flow ratio of cooked mash to steam of 6:1), and rectification (temperature of 65°C) to obtain medicinal ethanol.

[0048] 1.2 Investigation of process conditions

[0049] Fermentation was carried out according to the method under "1.1 Key Process Points" to prepare medicinal ethanol. The fermentation time and fermentation temperature were investigated as single factors. The optimal process conditions for producing medicinal ethanol by fermentation of waste molasses were explored by detecting and recording the sugar hammer degree, alcohol concentration and residual sugar content of the fermentation liquid before and after fermentation. The initial fermentation temperature was 30°C and the fermentation time was 72h.

[0050] The determination of sugar brix refers to the sugar brix meter method in the "Test Methods for Sugarcane Molasses Alcohol Production" [1] .

[0051] The alcohol content was determined by the distillation-alcoholometer method. The specific steps are as follows: 100 mL of fermentation liquid was measured with a measuring cylinder and placed in a distillation flask, 100 mL of distilled water was used to rinse the measuring cylinder, which was also placed in the distillation flask, and 100 mL of distillate was distilled and collected, and the alcohol concentration of the distillate was determined with an alcoholometer.

[0052] Residual sugar content was determined by 3,5-dinitrosalicylic acid colorimetry (DNS method). [2] .

[0053] 1.2.1 Fermentation temperature investigation

[0054] Fermentation was carried out according to the method under "1.1 Key Process Points" to prepare medicinal ethanol. The fermentation time was fixed at 72 h. The effects of fermentation temperatures of 28°C, 32°C, and 36°C on alcohol fermentation were investigated. The results are shown in Table 1.

[0055] Table 1 Effects of different fermentation temperatures on alcohol fermentation

[0056]

[0057] As shown in Table 1, when the fermentation temperature is 32°C, the alcohol content is the highest and the residual sugar content is the lowest. Therefore, 32°C is selected as the optimal process parameter for the fermentation temperature.

[0058] 1.2.1 Fermentation time investigation

[0059] Fermentation was carried out according to the method under "1.1 Key Process Points" to prepare medicinal ethanol. The fermentation temperature was fixed at 32°C, and the effects of fermentation times of 48h, 72h, and 96h on alcohol fermentation were investigated. The results are shown in Table 2.

[0060] Table 2 Effects of different fermentation times on alcohol fermentation

[0061]

[0062] As shown in Table 1, when the fermentation time is 72h, the alcohol content is the highest and the residual sugar content is the lowest, so 72h is selected.

[0063] h is the optimal process parameter for fermentation time.

[0064] Although the present invention has been described in detail above by means of general description, specific implementation methods and experiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

[0065] References:

[0066] [1] Liang Binghua, Cheng Qunqing, Wu Jiliang, et al. Inspection methods for sugarcane molasses alcohol production [M]. Guangzhou: Sugarcane and Sugar Research Institute, Ministry of Light Industry, 1986: 19-47.

[0067] [2] DUBOIS M, GILLES KA, HAMILTON JK, et al. Colorimetric method for determination sugars and related substances [J]. Journal Analytical Chemistry, 1956, 28: 350-356.

Claims

1. A method for producing medicinal ethanol by fermenting waste molasses, characterized in that: The method comprises the following steps: S1: adding a composite enzyme preparation consisting of lysozyme, pectinase, protease and cellulase to sugarcane molasses, mixing and treating at a temperature of 25 to 30° C. for 60 to 120 minutes to obtain enzyme-treated molasses; S2: dilute the enzyme-treated molasses obtained in the above step with distilled water to 20-35 BX, add dilute sulfuric acid to adjust the pH to 4-5, add nutrient salt and stir evenly, add 1‰-3‰ of active dry yeast for brewing with sugar cane molasses, and add 0.1‰-0.5‰ of urea with sugar cane molasses, mix evenly, and ferment at 28-36°C for 48-96h to obtain cooked mash; S3: The cooked mash obtained in the above steps is subjected to crude distillation, dealdehyde removal and rectification to obtain medicinal ethanol.

2. The method for producing medicinal ethanol by fermenting waste molasses according to claim 1, characterized in that: The mixing conditions in step S1 are: mixing at a temperature of 28° C. for 90 minutes.

3. The method for producing medicinal ethanol by fermenting waste molasses according to claim 1, characterized in that: The amount of the composite enzyme preparation added in step S1 is 0.3-0.5% of the amount of sugarcane molasses, and the composite enzyme preparation consists of 25%-35% lysozyme, 20%-30% pectinase, 10%-20% protease and 25%-35% cellulase.

4. The method for producing medicinal ethanol by fermenting waste molasses according to claim 3, characterized in that: The amount of the compound enzyme preparation added in step S1 is 0.4% of the amount of sugarcane molasses, and the compound enzyme preparation consists of 30% lysozyme, 25% pectinase, 15% protease and 30% cellulase.

5. The method for producing medicinal ethanol by fermenting waste molasses according to claim 1, characterized in that: The nutrient salt in step S2 is composed of ammonium sulfate, ammonium hydrogen phosphate and calcium chloride in a mass ratio of 2:2:1, and the added amount is 0.5% to 1% of the amount of sugarcane molasses.

6. The method for producing medicinal ethanol by fermenting waste molasses according to claim 1, characterized in that: In step S2, the inoculation amount of the active dry yeast for brewing is 2‰ of the amount of sugar cane molasses, the addition amount of urea is 0.3‰ of the amount of sugar cane molasses, and the fermentation condition is fermentation at 32%°C for 72 hours.

7. The method for producing medicinal ethanol by fermenting waste molasses according to claim 1, characterized in that: The crude distillation in step S3 is to evaporate the cooked mash and steam at a temperature of 60-78°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 1-3:1; the dealdehydeation is to evaporate the cooked mash and steam at a temperature of 78-100°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 3-7:

1.

8. The method for producing medicinal ethanol by fermenting waste molasses according to claim 7, characterized in that: The crude distillation in step S3 is to evaporate the cooked mash and steam at a temperature of 70-75°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 2-3:1; the dealdehydeation is to evaporate the cooked mash and steam at a temperature of 90-100°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 5-7:

1.

9. The method for producing medicinal ethanol by fermenting waste molasses according to claim 8, characterized in that: The crude distillation in step S3 is to evaporate the cooked mash and steam at a temperature of 75°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 3:1; the dealdehydeation is to evaporate the cooked mash and steam at a temperature of 95°C in a co-current manner, and the flow ratio of the cooked mash to the steam is 6:

1.

10. The method for producing medicinal ethanol by fermenting waste molasses according to claim 1, characterized in that: The treatment temperature of the distillation in step S3 is 65°C.

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