A method for extracting water-soluble capsaicin

Abstract

The present invention relates to the technical field of capsaicin production, and specifically discloses a method for extracting water-soluble capsaicin. The present invention utilizes enzymatic hydrolysis, subcritical water extraction and surfactant to prepare water-soluble capsaicin, and no organic solvent is required in the extraction process, and the yield of water-soluble capsaicin can reach 85%. At the same time, the technical solution of the present invention has a short process route, low equipment cost, low operating cost, environmental friendliness, low production risk, and is easier to achieve industrialization. The capsaicin extracted by the technical solution of the present invention does not have the problem of organic solvent residue, has good water solubility, is safe and reliable, can be safely used in a variety of fields including the food field, and can significantly improve the application scenarios of capsaicin.

Description

Technical Field

[0001] The invention belongs to the technical field of capsaicin production, and in particular relates to a method for extracting water-soluble capsaicin. Background Art

[0002] Capsaicin is the main biologically active substance in chili peppers that causes spicy taste. Its content in chili peppers is 0.1-1%. It has the effects of analgesia and itching, anti-inflammatory and swelling, antibacterial and anti-tumor, myocardial and gastrointestinal protection, appetite regulation, fat metabolism promotion, tear-inducing and sneezing-inducing, and rheumatism prevention and treatment.

[0003] The traditional methods for extracting and separating capsaicin from red peppers are mainly acid-base method and organic solvent method. Although the operation is simple, the product has many impurities, difficult purification, high cost and easy to cause pollution; some researchers also use ultrasound, microwave, enzymatic hydrolysis and other technologies for auxiliary extraction, but these methods have limited improvement in extraction efficiency, and still need to use organic solvents as extraction solvents, and cannot solve the problem of organic solvent residues; in recent years, some emerging extraction methods have also been reported, such as supercritical fluid extraction, two-phase aqueous extraction, ionic liquid method, etc. Although these methods can produce finished products with high yield and quality, and relatively less pollution, the equipment cost investment is large, considering safety, process, cost, separation and purification process and other issues, especially the above extraction research system is generally biased towards laboratory system, in the subsequent amplification test process, pilot and even formal production, there are problems such as process amplification and material cost accounting that need to be further improved and solved. Therefore, a capsaicin extraction method based on aqueous phase as extraction solvent, simple process route, low equipment cost, and suitable for large-scale industrial production is urgently needed to be developed.

[0004] At the same time, due to the poor solubility of natural capsaicin in water, the application of capsaicin is greatly limited, so water-soluble capsaicin has become a hot topic in the deep processing of capsaicin. At present, most water-soluble capsaicin products are converted by adding emulsifiers to oil-soluble capsaicin. Most of the oil-soluble capsaicin used in such products is extracted by organic solvents, which cannot solve the problem of solvent residue. 201810628382.0 discloses a production process of water-soluble capsaicin, in which the pepper skin is countercurrently leached with an alkaline extract, and the solution obtained in the upper layer is adsorbed by capsaicin through a macroporous resin. The adsorbed solution is circulated back to the countercurrent leaching of the pepper skin, and then adsorbed. In this cycle, the capsaicin adsorbed in the macroporous resin is eluted with ethanol, evaporated and concentrated, and a water-soluble capsaicin solution is obtained. This process uses the property of capsaicin being soluble in alkaline solution to improve the water solubility of capsaicin, but this will also limit the application scenarios of water-soluble capsaicin, and the use of strong alkali will also affect the safety of the product. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned problems existing in the prior art and provide a method for extracting water-soluble capsaicin. Water-soluble capsaicin is efficiently prepared by combining enzymatic hydrolysis, subcritical water extraction and surfactant. No organic solvent is required in the extraction process. Cellulase, pectinase and papain are used to break down the barrier of the cell wall. Combined with the solubilization effect of surfactant, subcritical water extraction is used to dissolve capsaicin to a large extent. The yield of water-soluble capsaicin extracted by this method can be as high as 85%. The capsaicin extracted by this method is safe and reliable, and can be safely used in a variety of fields including the food field, which can significantly improve the application scenarios of capsaicin.

[0006] To achieve the above objectives, the inventors conducted in-depth research and completed the solution of the present invention after repeated research and demonstration, which is as follows:

[0007] In a first aspect, the present invention provides a method for extracting water-soluble capsaicin, characterized in that the method comprises the following steps:

[0008] 1) Grinding: Grind the dried chili pepper and sieve it;

[0009] 2) Enzymatic hydrolysis: After mixing chili powder with water, add pectinase, cellulase and papain, and stir for enzymatic hydrolysis;

[0010] 3) Extraction: Add surfactant to the mixture after enzymatic hydrolysis, put it into an extraction tank, heat and pressurize it to make the water in the device in a subcritical state, and extract it for 30-50 minutes at the same temperature and pressure. After the extraction is completed, cool the extract;

[0011] 4) Filtration: The extract can be centrifuged to obtain water-soluble capsaicin.

[0012] Furthermore, in the step 2), the mass ratio of chili powder to water is 1:(8-12), and the amounts of pectinase, cellulase and papain corresponding to each 1g of the mixture of chili powder and water are 40-60U / g, 12-18U / g and 80-120U / g respectively.

[0013] Furthermore, in the step 2), the enzymolysis temperature is 50-60° C. and the time is 4-8 h.

[0014] Furthermore, in step 3), the surfactant includes one or more of Tween-80, sodium stearoyl lactylate, and Quillaja saponaria bark extract, preferably Tween-80.

[0015] Furthermore, the surfactant is added in an amount of 0.5-2% (w / v) of the mixture.

[0016] Furthermore, in step 3), the extraction temperature is 140-200° C. and the pressure is 0.5-5 MPa, preferably the extraction temperature is 200° C. and the pressure is 5 MPa.

[0017] Furthermore, in the step 3) the extraction process, the liquid in the extraction tank may be stirred at a rotation speed of 110-130 rpm / min.

[0018] In a second aspect, the present invention further provides a water-soluble capsaicin, characterized in that the water-soluble capsaicin is prepared by the method described in the present invention.

[0019] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0020] 1. The present invention utilizes enzymolysis, subcritical water extraction and surfactant to prepare water-soluble capsaicin. No organic solvent is needed in the extraction process. Cellulase, pectinase and papain are used to dissolve the barrier of the cell wall. The solubilization effect of the surfactant is combined with subcritical water extraction to dissolve the capsaicin to a great extent. The water-soluble capsaicin can be extracted by this method, and the capsaicin yield can be as high as 85%.

[0021] 2. The technical solution of the present invention has a short process route, low equipment cost, low operating cost, environmental friendliness, low production risk, and is easier to industrialize.

[0022] 3. The capsaicin extracted by the technical solution of the present invention does not have the problem of organic solvent residue, has good water solubility, is safe and reliable, can be safely used in various fields including the food field, and can significantly improve the application scenarios of capsaicin. DETAILED DESCRIPTION

[0023] In order to facilitate the understanding of the present invention, the present invention will be described more fully below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0024] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0025] Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional food-grade reagents, methods and equipment in the art.

[0026] The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0027] The capsaicin content determination method used in the present invention-high performance liquid chromatography:

[0028] 1. Sample processing:

[0029] Dried chili sample: Crush the sample with an electric grinder, pass it through a 60-mesh sieve, weigh 2.50-5.00 g (accurate to 0.0001 g, adjusted according to the capsaicin content in the sample) into a 50 mL centrifuge tube as a reference for calculating the recovery rate of capsaicin.

[0030] Capsaicin extract sample: weigh 2.50-5.00 g (accurate to 0.0001 g, adjusted according to the capsaicin content in the sample) of the capsaicin extract in the example into a 50 mL centrifuge tube.

[0031] 2. Sample extraction:

[0032] Mix methanol and tetrahydrofuran in a ratio of 1:1, take 25mL and add it to the sample, and extract it in a water bath with ultrasound at 60℃ for 30min. Collect the clear liquid by centrifugation, add 25mL of the above methanol and tetrahydrofuran mixed solution to the filter residue again, use ultrasound to extract for 10min, repeat twice, and combine the three filtrates. Concentrate the extract to 15-20mL using a rotary evaporator, then make up to 50mL with the mixed solution, and dilute appropriately according to the concentration requirements. Filter through a 0.45μm filter membrane and perform chromatographic analysis.

[0033] Chromatographic conditions:

[0034] Chromatographic column: ZORBAX Eclipse Plus C18 2.1×150mm 1.8μm

[0035] Mobile phase: methanol + water (65 + 35)

[0036] Injection volume: 10 μL

[0037] Flow rate: 1mL / min

[0038] Detection wavelength: 280nm

[0039] Column oven temperature: 30°C

[0040] Capsaicin yield calculation method:

[0041] Capsaicin yield = (m 1 *c 1 ) / (m 2 *c 2 )

[0042] m 1 :Capsaicin extract sample quality

[0043] c1 :Capsaicin content measured in capsaicin extract samples

[0044] m 2 :Dried chili sample quality

[0045] c 1 : Capsaicin content measured in dried chili pepper samples

[0046] Example 1 Surfactant Effect Test

[0047] Take 50g of dried chili as raw material and crush it through a 60-mesh sieve. Mix chili powder and water in a weight ratio of 1:10, add 50U / g pectinase, 15U / g cellulase and 100U / g papain, stir and extract, the temperature is 55°C, and the time is 4 hours. Add surfactants to the mixture after enzymolysis as shown in Table 1, put it into the extraction tank, seal the tank, turn on the agitator, adjust it to 120rpm / min, turn on the heater, heat it to 140°C, and the pressure in the kettle is 0.5MPa, so that the water in the device is in a subcritical state, and keep it warm and pressurized for 40min. After the extraction is completed, turn on the circulating pump, cool the steam released from the extraction tank with cooling water, and further cool it after passing through the low-temperature cooling tank, and finally the extract enters the receiving tank. The extract can be filtered with a tripod centrifuge to obtain water-soluble capsaicin. Samples are taken to measure the capsaicin content, and the capsaicin yield is calculated. The results are recorded in Table 2.

[0048] Table 1 Surfactant types and addition amounts

[0049] Group Surfactant Type Surfactant addition amount Group 1 - - Group 2 Twain-80 0.5%(w / v) Group 3 Quillaja bark extract 2%(w / v) Group 4 Sodium Stearoyl Lactylate 0.5%(w / v)

[0050] Table 2 Capsaicin yield in different groups

[0051] Group Capsaicin yield Group 1 40％ Group 2 72％ Group 3 58％ Group 4 67％

[0052] From the results in Table 2, it can be seen that the addition of surfactants can significantly increase the yield of water-soluble capsaicinoids, and the addition of different surfactants has different yields of water-soluble capsaicinoids. When 0.5% Tween-80 is added, the yield of capsaicinoids in water can reach 72%. After adding 2% of the natural surfactant Quillaja bark extract, the yield is increased to 58%, and the addition of 0.5% sodium stearoyl lactylate can increase the yield to 67%.

[0053] Example 2 Subcritical water extraction effect test

[0054] Take 50g dried chili as raw material and crush it through a 60-mesh sieve. Chili powder and water are mixed in a weight ratio of 1:10 to form an enzymatic solution, and 50U / g pectinase, 15U / g cellulase and 100U / g papain are added, and the mixture is stirred and extracted at a temperature of 50°C for 8 hours. 0.5% (w / v) Tween-80 is added to the mixture after enzymatic hydrolysis, and the mixture is placed in an extraction tank. The tank body is sealed, and the parameters are set according to the conditions shown in Table 3 so that the water in the device is in a subcritical state, and the extraction is carried out under heat preservation and pressure. After the extraction is completed, the circulating pump is turned on, and the steam released from the extraction tank is cooled with cooling water, and further cooled after passing through a low-temperature cooling tank, and the final extract enters a receiving tank. The extract is filtered with a tripod centrifuge to obtain water-soluble capsaicin. Samples are taken to measure the capsaicin content, and the capsaicin yield is calculated. The results are recorded in Table 4.

[0055] Table 3 Capsaicin yield in different groups

[0056] Group Agitator speed temperature pressure Extraction time Group 5 - - - - Group 6 120rpm / min 140℃ 0.5MPa 50min Group 7 120rpm / min 160℃ 2MPa 40min Group 8 120rpm / min 200℃ 5MPa 30min Group 9 120rpm / min 300℃ 20MPa 30min

[0057] Table 4 Capsaicin yield in different groups

[0058] Group Capsaicin yield Group 5 61％ Group 6 76％ Group 7 80％ Group 8 82％ Group 9 85％

[0059] From the results in Table 4, it can be seen that subcritical water extraction can increase the solubility of capsaicin in water. When using subcritical water to extract capsaicin, different extraction conditions will have a certain impact on the yield of capsaicin. Increasing temperature and pressure helps to improve the water solubility of capsaicin; however, in our test, we observed that the capsaicin solution extracted by Group 9 would show stratification after being placed at room temperature for 1 hour, while other groups did not show this phenomenon. It is considered that the extract contains more fat-soluble impurities due to excessively high temperature and pressure, resulting in oil-water separation, indicating that excessively high temperature and pressure are not conducive to the extraction of water-soluble capsaicin.

[0060] Example 3 Capsaicin extraction test

[0061] Take 50g dried chili as raw material and crush it through a 60-mesh sieve. Mix chili powder and water in a weight ratio of 1:10, add 50U / g pectinase and 15U / g cellulase, stir and extract at a temperature of 60°C for 4 hours. Add 0.5% (w / v) Tween-80 to the mixture after enzymolysis, put it into an extraction tank, seal the tank, turn on the agitator, adjust it to 120rpm / min, turn on the heater, heat to 200°C, the pressure in the kettle is 5MPa, and extract for 40min with heat preservation and pressure. After the extraction is completed, turn on the circulating pump, cool the steam released from the extraction tank with cooling water, further cool it after passing through a low-temperature cooling tank, and finally the extract enters the receiving tank. The extract can be filtered with a three-legged centrifuge to obtain water-soluble capsaicin. Sample and measure the capsaicin content, and the capsaicin yield is calculated to be 85%.

[0062] Comparative Example 1

[0063] Take 50g of dried chili pepper as raw material, crush it through a 60-mesh sieve. Mix chili powder with 40% ethanol at a weight ratio of 1:10, stir and extract at room temperature for 4 hours, and filter to obtain capsaicin extract. Take a sample to measure the capsaicin content, and calculate the capsaicin yield to be 63%.

[0064] Comparative Example 2

[0065] Take 50g of dried chili as raw material and crush it through a 60-mesh sieve. Mix chili powder and water in a weight ratio of 1:10, add 0.5% (w / v) Tween-80, put it in an extraction tank, seal the tank, turn on the agitator, adjust it to 120rpm / min, turn on the heater, heat it to 140°C, the pressure in the kettle is 0.5MPa, so that the water in the device is in a subcritical state, and extract it under heat and pressure for 50min. After the extraction is completed, turn on the circulating pump, cool the steam released from the extraction tank with cooling water, further cool it after passing through a low-temperature cooling tank, and finally the extract enters the receiving tank. The extract is filtered with a three-legged centrifuge to obtain a capsaicin extract. Samples are taken to measure the capsaicin content, and the capsaicin yield is calculated to be 55%.

[0066] According to Examples 1-3 and Comparative Examples 1-2, enzymolysis, subcritical water extraction and surfactant can increase the water solubility of capsaicin to a certain extent. The present invention utilizes enzymolysis, subcritical water extraction and surfactant to efficiently prepare water-soluble capsaicin, further strengthening the effect of each technology used alone, and finding out the most suitable surfactant and subcritical water extraction conditions for water-soluble capsaicin extraction through comparative experiments, and extracting water-soluble capsaicin using this method, without the use of organic solvents, the capsaicin yield can be as high as 85%, significantly higher than the low-concentration organic solvent extraction yield. The technical solution of the present invention has a short process route, low equipment cost, low operating cost, environmental friendliness, low production risk, and is more easily industrialized, and the capsaicin extracted by the technical solution of the present invention does not have the problem of organic solvent residue, has good water solubility, is safe and reliable, can be safely used in a variety of fields including the food field, and can significantly improve the application scenarios of capsaicin.

[0067] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for extracting water-soluble capsaicin, It is characterized in that The method comprises the following steps: 1) Grinding: Grind the dried chili pepper and sieve it; 2) Enzymatic hydrolysis: Mix chili powder with water, add pectinase, cellulase and papain, and stir for enzymatic hydrolysis; 3) Extraction: Add surfactant to the mixture after enzymatic hydrolysis, put it into an extraction tank, heat and pressurize it to make the water in the device in a subcritical state, and extract it for 30-50 minutes under heat and pressure. After the extraction is completed, cool the extract. The extraction temperature is 140-200°C and the pressure is 0.5-5 MPa; 4) Filtration: The extract can be centrifuged to obtain water-soluble capsaicin; In step 3), the surfactant comprises one or more of Tween-80, sodium stearoyl lactylate, and Quillaja saponaria bark extract, and the surfactant is added in an amount of 0.5-2% (w / v) of the mixture.

2. The method according to claim 1, It is characterized in that In the step 2), the mass ratio of chili powder to water is 1:(8-12), and the amounts of pectinase, cellulase and papain corresponding to 1g of the mixture of chili powder and water are 40-60U / g, 12-18U / g and 80-120U / g respectively.

3. The method according to claim 1, It is characterized in that In step 2), the enzymatic hydrolysis temperature is 50-60° C. and the time is 4-8 hours.

4. The method according to claim 1, It is characterized in that The surfactant is Tween-80.

5. The method according to claim 1, It is characterized in that In step 3), the extraction temperature is 200° C. and the pressure is 5 MPa.

6. The method according to any one of claims 1 to 5, It is characterized in that In the step 3) of the extraction process, the liquid in the extraction tank may also be stirred at a rotation speed of 110-130 rpm / min.