A method for extracting capsicum oleoresin from industrial pepper

Abstract

The invention discloses a method for extracting capsicum oleoresin from industrial peppers, which mainly comprises the following steps: pickling and separating the pepper powder, extracting with caprylic decanoic acid glyceride and glycerol as extraction solvents, separating the solvent, membrane separation, adding surfactant emulsification, and then extracting with n-butanol. The method of the invention removes most of the acid-soluble odorous substances and substances with large polarity that are not conducive to the flow of the extract by pretreatment with an organic acid solution, further separates capsaicin from impurities by using caprylic decanoic acid glyceride and glycerol as extraction solvents, and then emulsifies the odorous substances with poor water solubility by using a surfactant to make the odorous substances more soluble in water, extracts capsaicin with n-butanol, and removes stubborn odorous substances. The method of the invention can effectively improve the fluidity of capsicum oleoresin, improve the extraction efficiency, and effectively remove the rancid smell, and is suitable for industrialized scale-up production and expanding the application in food additives.

Description

Technical Field

[0001] The invention relates to a method for extracting capsicum oleoresin from industrial capsicum. Background Art

[0002] Industrial pepper is a type of pepper with 10-20 times the capsaicin content of chili pepper, and is mainly used as a raw material for industrial extraction of natural capsaicin. Industrial pepper extract (i.e. capsicum oleoresin) can be used in many fields such as food additives, biomedicine, military manufacturing, green pesticides, etc., among which the demand for food additives is huge.

[0003] Industrial pepper is an economic crop with great prospects. Yunnan Province is very suitable for the growth of industrial pepper due to its unique geographical and climatic environment. The planting area is increasing by 10-30% every year, bringing higher returns to growers. Industrial pepper is considered to be an economic crop that may replace tobacco, so agricultural departments and cooperatives in various places are vigorously promoting its planting.

[0004] Chili oil, also known as capsicum oleoresin, is widely used as a food additive (such as hot pot base, stewed food, etc.) because it contains capsaicin. China is a big country in catering, and a large amount of spicy agents are needed for cooking and seasoning. Industrial peppers have a high content of capsaicin and have a high added value of extraction. Extracting capsicum oleoresin with high capsaicin content from industrial peppers is a good choice. However, the fat-soluble components in industrial pepper extracts (capsicum oleoresin) are less, the fluidity is poor, and the wall is seriously attached during the production process, which is easy to block the pipeline and the recovery rate is low; secondly, the extract contains some special ingredients, which makes it have a special heavier rancid smell. The substance that produces the rancid smell is similar to capsaicin in nature and is difficult to separate. The obvious rancid smell makes it difficult to accept the food manufacturing used for food additives at the back end.

[0005] At present, the commonly used oil deodorization methods mainly include high temperature method, adsorption method, molecular distillation method, salt washing method, etc. These conventional oil deodorization technologies have no obvious deodorization effect on industrial pepper extracts. The extract (pepper oleoresin) has poor fluidity, serious wall adhesion and easy to block the pipeline, and the rancid smell has not been solved, which is still a major difficulty that plagues the extraction industry. It is necessary to develop a new extraction and separation process to produce oleoresins that meet the requirements of the food additive market, so as to promote the long-term development of the industrial pepper industry. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the above-mentioned defects and provide a method for extracting capsicum oleoresin from industrial peppers with simple process and low production cost, which can effectively improve the fluidity of capsicum oleoresin, improve the extraction efficiency, and effectively remove the rancid smell, and is suitable for industrialized scale-up production and expanding the application in food additives.

[0007] The method for extracting capsicum oleoresin from industrial capsicum of the present invention comprises the following steps:

[0008] (1) Grinding the raw materials: Grinding the dried chili pepper into 50-80 meshes to obtain chili powder;

[0009] (2) pickling the chili powder, putting it into a stirring tank, adding an organic acid aqueous solution 10 times the weight of the chili powder, stirring and washing at room temperature for 1-2 hours to obtain a pickled product;

[0010] (3) removing the organic acid aqueous solution in the pickled product by a filter press and retaining the filter residue;

[0011] (4) extracting the filter residue and putting it into an extraction tank, adding an extraction solvent composed of caprylic acid decanoate and glycerol in a volume ratio of 1:2 in an amount 10 times the weight of the chili powder, stirring and extracting at 80-90° C. for 2-3 hours, separating the solid and liquid with a filter press, and retaining the extract;

[0012] (5) Separating the solvent The extract is separated from the glycerol caprylate and glycerol in the extraction solvent by a liquid-liquid separation centrifuge, and the obtained glycerol phase is a capsicum oleoresin phase rich in capsaicinoids;

[0013] (6) Membrane separation: the glycerol phase enters a membrane separator with a membrane pore size of 200 DA for separation, the permeate is glycerol, and the capsicum oleoresin rich in capsaicin is retained in the retentate;

[0014] (7) adding water and 1-5% of the weight of the surfactant to the emulsified retentate, adjusting the pH value of the retentate to greater than 8.0, stirring at room temperature for 30 minutes, adding 25-35% of the volume of the retentate with n-butanol, stirring and extracting for 10 minutes, and separating the n-butanol layer with a liquid-liquid separation centrifuge to obtain an n-butanol extract;

[0015] (8) Removal of solvent: The n-butanol extract enters a vacuum concentrator, and the n-butanol is recovered under reduced pressure at 105° C., and what remains is capsicum oleoresin rich in capsaicin.

[0016] Furthermore, in step (2) of the present invention, the organic acid is an aqueous solution of acetic acid, an aqueous solution of citric acid or an aqueous solution of malic acid with a mass concentration of 2%.

[0017] Furthermore, in step (7) of the present invention, the surfactant is polysorbate 80, polyoxyethylene fatty acid ester, polyoxyethylene fatty alcohol ether or glyceryl monostearate.

[0018] Preferably, in step (7) of the present invention, the pH value of the retentate is adjusted using sodium hydroxide, potassium hydroxide or aqueous ammonia.

[0019] The method for extracting capsicum oleoresin from industrial capsicum according to the present invention comprises the following steps: firstly, pre-treating (extracting or acid washing) with an organic acid solution to remove most of the acid-soluble odorous substances and substances with high polarity that are not conducive to the flow of the extract; secondly, using a unique extraction solvent, namely, caprylic acid decanoate and glycerol, so that capsaicin enters the glycerol phase and impurities enter caprylic acid decanoate, and capsaicin is further separated from the impurities, and capsaicin and fat-soluble substances that are conducive to the flowability of the extract are effectively extracted; finally, using a surfactant (represented by polysorbate-80) to emulsify the odorous substances with poor water solubility to make the odorous substances more soluble in water, and at this time, using n-butanol to extract capsaicin, so that the odorous substances and impurities that affect the flowability are completely separated from the capsaicin, and the design of this step enables the removal of stubborn odorous substances.

[0020] Beneficial effects of the present invention: Compared with the prior art, the method of the present invention has significant improvements in the fluidity and deodorization of the extract.

[0021] Extraction: Capsaicin is an alcohol-soluble substance. In the prior art, polar solvents such as methanol, ethanol, and acetone are commonly used for extraction. The resulting extract has few fat-soluble components and therefore has poor fluidity. The method described in the present invention uses caprylic acid glyceride and glycerol as extraction solvents. Caprylic acid glyceride mainly extracts fat-soluble substances and inhibits the dissolution of water-soluble components. The fat-soluble components in the resulting extract are increased, which greatly improves the fluidity of the extract and effectively solves the problem of serious wall adhesion and pipeline blockage and low recovery rate during the production process.

[0022] Deodorization: Capsicum oleoresin contains some components (impurities, rancid smell) with similar properties to those of capsicum oleoresin, and the existing extraction process cannot remove these components, so that the extracted capsicum oleoresin has a strong rancid smell. The method of the present invention first removes most of the acid-soluble odorous substances by leaching with an organic acid solution. If there are still some residues, the pH is adjusted to 8.0, and a specific surfactant is added to emulsify the odorous substances to increase the water solubility. Capsaicin is easily extracted by n-butanol, and the impurities such as the odorous substances are completely separated.

[0023] The capsicum oleoresin extracted by the method of the invention has the characteristics of good fluidity and no odor. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a comparison chart of the fluidity test of the capsicum oleoresin extracted by the embodiment of the present invention and the comparative example. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with embodiments.

[0026] Example: Extraction of capsicum oleoresin from industrial peppers by the method of the present invention

[0027] (1) Grinding the raw materials: Grind the dried chili pepper into 50-80 mesh to obtain chili powder.

[0028] (2) Pickling: 100 g of chili powder was weighed and put into a stirring tank, and 1 kg of acetic acid aqueous solution with a mass concentration of 2% was added. The mixture was stirred and washed at room temperature for 1.5 hours to obtain a pickled product. After pickling, most of the odorous substances in the extract were removed.

[0029] (3) Separation: Use a filter press to remove the acetic acid aqueous solution in the obtained pickled product and retain the filter residue.

[0030] (4) Extraction: The filter residue is placed in an extraction tank, and 1 kg of an extraction solvent composed of caprylic acid glyceride and glycerol in a volume ratio of 1:2 is added. The extraction is stirred at 85° C. for 2.5 hours, and the extract is pressed out with a filter press to separate the solid and liquid. The filter residue is discarded and the extract is retained.

[0031] (5) Separation of solvent: Caprylic decanoic acid glyceryl and glycerol are separated by a liquid-liquid separation centrifuge, and impurities enter the caprylic decanoic acid glyceryl. The resulting glycerol phase is a capsicum oleoresin phase rich in capsaicin.

[0032] (6) The glycerol phase obtained by membrane separation enters a membrane separator with a membrane pore size of 200DA. The capsicum oleoresin rich in capsaicin is retained in the retentate, and the permeate is glycerol.

[0033] (7) Add an appropriate amount of water and 1-5% of polysorbate 80 by weight of the retentate to the emulsified retentate, adjust the pH value of the retentate to 9.0 with sodium hydroxide, stir at room temperature for 30 minutes, add 500 ml of n-butanol, stir and extract for 10 minutes, separate the n-butanol layer with a liquid-liquid separation centrifuge to obtain an n-butanol extract; at this pH value, after emulsification with polysorbate 80, the odorous substances become more soluble in water, so that the stubborn odorous substances can be removed.

[0034] (8) Removal of solvent: The n-butanol extract enters a vacuum concentrator and is vacuum-concentrated at 105° C. to recover n-butanol, leaving capsicum oleoresin rich in capsaicin. In this example, 15.5 g of capsicum oleoresin was obtained.

[0035] Comparative Example 1: High temperature deodorization method

[0036] (1) Crush the dried chili pepper into 50-80 mesh.

[0037] (2) Weigh 100 g of chili powder and put it into a mixing tank. Add 1 kg of ethanol and stir and extract at 85°C for 2.5 hours.

[0038] (3) Use a filter press to press out the extract and discard the filter residue.

[0039] (4) recovering ethanol under reduced pressure to obtain capsicum oleoresin.

[0040] (5) The obtained capsicum oleoresin was further deodorized at 115°C for 30 minutes to obtain 31.9 g of deodorized capsicum oleoresin.

[0041] Comparative Example 2: Activated carbon deodorization method

[0042] (1) Crush the dried chili pepper into 50-80 mesh.

[0043] (2) Weigh 100 g of chili powder and put it into a mixing tank. Add 1 kg of ethanol and stir and extract at 85°C for 2.5 hours.

[0044] (3) Use a filter press to press out the extract and discard the filter residue.

[0045] (4) Add activated carbon in an amount of 1% by weight of the extract to the extract, and stir at room temperature to deodorize for 2 hours.

[0046] (5) filtering to remove activated carbon, recovering ethanol under reduced pressure, and obtaining 24.9 g of capsicum oleoresin.

[0047] Comparative Example 3: Salt washing deodorization method

[0048] (1) Crush the dried chili pepper into 50-80 mesh.

[0049] (2) Weigh 100 g of chili powder and put it into a mixing tank. Add 1 kg of ethanol and stir and extract at 85°C for 2.5 hours.

[0050] (3) Use a filter press to press out the extract and discard the filter residue.

[0051] (4) recovering ethanol under reduced pressure to obtain capsicum oleoresin.

[0052] (5) Add 5 times the weight of 5% sodium bicarbonate solution to the capsicum oleoresin and stir and wash at 70°C for 2 hours.

[0053] (6) The aqueous layer was separated and the resin layer was dried to obtain 29.8 g of capsicum oleoresin.

[0054] Comparative Example 4: No pickling at the front end, the rest is the same as in Example

[0055] (1) Crushing raw materials is the same as in the embodiment

[0056] (2) Extraction: Weigh 100 g of chili powder and put it into an extraction tank. Add 1 kg of a solvent composed of caprylic acid glyceride and glycerol in a volume ratio of 1:2. Stir and extract at 85°C for 2.5 hours. Press out the extract with a filter press, separate the solid and liquid, discard the filter residue, and retain the extract.

[0057] (3) Separation of solvent: Caprylic / capric glyceride and glycerol are separated by a liquid-liquid separation centrifuge, and the obtained glycerol phase is the capsicum oleoresin phase.

[0058] (4) Membrane separation is the same as in the example.

[0059] (5) Emulsification is the same as in Example 1.

[0060] (6) Removing the solvent was the same as in the previous embodiment to obtain 21.6 g of capsicum oleoresin.

[0061] Comparative Example 5: No emulsification and deodorization, the rest is the same as in Example

[0062] (1) The raw materials are crushed as in the example.

[0063] (2) Pickling is the same as in the example.

[0064] (3) Separation is the same as in the embodiment.

[0065] (4) Extraction is the same as in Example 1.

[0066] (5) Separation solvent is the same as in the embodiment.

[0067] (6) Membrane separation is the same as in the example.

[0068] (7) Adjusting the pH value: Add an appropriate amount of water to the retentate obtained, adjust the pH value of the retentate to 9.0 with sodium hydroxide, stir at room temperature for 30 minutes, add 500 ml of n-butanol, stir and extract for 10 minutes.

[0069] (8) Removal of solvent: The same as in the previous embodiment, extraction to obtain 18.9 g of capsicum oleoresin.

[0070] Comparative Example 6: This comparative example tests the effect of the emulsification effect of surfactants on the extract at pH < 8.0

[0071] The extraction method of this comparative example is the same as that of the embodiment, except that the pH value of the retentate obtained in step (7) is adjusted to 7.0 with sodium hydroxide, and 16.9 grams of capsicum oleoresin is extracted.

[0072] Among the capsicum oleoresin extracted in the above examples, the amount extracted in the embodiment is the least, which means that the impurities in the extract of the embodiment are removed the most and the capsaicin purity is high.

[0073] The industry believes that the odorous substances in capsicum oleoresin are some unsaturated fatty acids, hydrogen sulfide or other substances with certain volatility. The residual amount of odorous substances in the capsicum oleoresin extracted from the embodiments and comparative examples was detected by gas chromatography. The results are shown in Table 1.

[0074] Table 1: Comparison of the residual amount of odorous substances in the capsicum oleoresin extracted from each experimental example

[0075]

[0076] It can be seen from the data in Table 1 that although the traditional high temperature method, adsorption method (activated carbon deodorization), salt washing method and other methods have a certain deodorization effect, the effect is not ideal. A large amount of odorous substances remain in the extract, which is far from meeting the requirements of food application; the results of Comparative Example 4 show that the residual odorous substances are significantly higher than those of other examples, indicating that in the method described in the present invention, the early acid washing plays an extremely important role in removing odorous substances; from the results of Comparative Examples 4, 5 and 6 and the embodiments, it can be seen that the method described in the present invention (embodiment) removes odorous substances thoroughly, and the extracted capsicum oleoresin can meet the requirements of food application as a food additive.

[0077] The deodorizing effect of the method of the present invention can also be verified by manual evaluation. Ten people with normal taste discrimination function were selected to blindly test and score the capsicum oleoresin extracted from the embodiments and comparative examples, and different scores were given for different odor levels: almost odorless was given 10 points, relatively light odor was given 8 points, relatively heavy odor was given 6 points, and very heavy odor was given 2 points. The statistical results are shown in Table 2.

[0078] Table 2: Blind test scores of tasters on various capsicum oleoresins

[0079] Example Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Person 1 10 8 6 6 2 8 8 Person 2 10 8 6 2 2 8 8 Person 3 10 8 6 2 2 8 8 Person 4 10 6 6 2 2 8 8 Person 5 10 8 8 2 2 8 8 Personnel 6 10 8 6 6 2 8 8 Personnel 7 10 6 6 2 2 8 8 Personnel 8 10 6 6 2 2 8 8 Personnel 9 10 8 8 2 2 8 8 Personnel 10 10 8 6 2 2 8 8

[0080] The scoring results are basically consistent with the instrument test data, indicating that the capsicum oleoresin extracted in the embodiment has the best deodorizing effect and can fully meet the application in the back-end food manufacturing field.

[0081] Fluidity test: Take the capsicum oleoresin prepared in Example, Comparative Example 1, Comparative Example 2 and Comparative Example 3 respectively, heat them to 80°C, draw a horizontal line on a white board, take 3 ml of each and drop it under the corresponding experimental name on the same horizontal line with a sampler, place the white board vertically for 1 minute, observe and record the flow state, and the results are shown in Figure 1 ; The farther the end point of the flow is from the starting point horizontal line, the better the fluidity. Figure 1 It is clearly shown that the fluidity of the capsicum oleoresin extracted by Example (the method of the present invention) is significantly better than the fluidity of the capsicum oleoresin extracted by Comparative Examples 1, 2 and 3.

[0082] The above are only some implementation methods of the present invention. The embodiments are only for more clearly illustrating the technical solution, and are not used to limit the technical solution. A person skilled in the art can know from the description that the technical solution of the present invention can be implemented in many ways. As long as the above-mentioned technical solution is used, it should fall within the protection scope of the present invention.

Claims

1. A method for extracting capsicum oleoresin from industrial pepper, characterized in that: The method comprises the following steps: (1) Grinding the raw materials: Grind the dried chili pepper into 50-80 mesh to obtain chili powder; (2) Pickling: the chili powder is put into a stirring tank, an organic acid aqueous solution of 10 times the weight of the chili powder is added, and the mixture is stirred and washed at room temperature for 1-2 hours to obtain a pickled product; (3) removing the organic acid aqueous solution in the pickled product by a separation filter press, and retaining the filter residue; (4) extracting the filter residue and putting it into an extraction tank, adding an extraction solvent composed of caprylic acid glyceride and glycerol in a volume ratio of 1:2 in an amount 10 times the weight of the chili powder, stirring and extracting at 80-90° C. for 2-3 hours, separating the solid and liquid with a filter press, and retaining the extract; (5) Separating the solvent: the extract is separated from the glycerol in the extraction solvent by a liquid-liquid separation centrifuge, and the obtained glycerol phase is a capsicum oleoresin phase rich in capsaicinoids; (6) Membrane separation: the glycerol phase enters a membrane separator with a membrane pore size of 200 DA for separation, the permeate is glycerol, and the capsicum oleoresin rich in capsaicin is retained in the retentate; (7) adding water and 1-5% by weight of a surfactant to the emulsified retentate, adjusting the pH value of the retentate to >8.0, stirring at room temperature for 30 minutes, adding 25-35% by volume of n-butanol to the retentate, stirring and extracting for 10 minutes, separating the n-butanol layer with a liquid-liquid separation centrifuge to obtain an n-butanol extract; (8) Removal of solvent: The n-butanol extract enters a vacuum concentrator, where the n-butanol is recovered under reduced pressure at 105° C., and what remains is capsicum oleoresin rich in capsaicin.

2. The method for extracting capsicum oleoresin from industrial pepper according to claim 1, characterized in that: In the step (2), the organic acid is an aqueous solution of acetic acid, an aqueous solution of citric acid or an aqueous solution of malic acid with a mass concentration of 2%.

3. The method for extracting capsicum oleoresin from industrial pepper according to claim 1, characterized in that: In the step (7), the surfactant is polysorbate 80, polyoxyethylene fatty acid ester, polyoxyethylene fatty alcohol ether or glyceryl monostearate.

4. The method for extracting capsicum oleoresin from industrial pepper according to claim 1, characterized in that: In the step (7), the pH value of the retentate is adjusted using sodium hydroxide, potassium hydroxide or aqueous ammonia.

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