Process for refining zanthoxylum bungeanum maxim extract

Abstract

The invention relates to the technical field of food processing, in particular to a zanthoxylum bungeanum maxim extract refining process which comprises the following steps: S01, preparing a zanthoxylum bungeanum maxim oil extract; s02, mixing and stirring the zanthoxylum oil extract and saline water according to a mass ratio of 1: (3-4) for 30-35 minutes, standing for 3-5 hours, and separating supernatant liquid to obtain a primary extract; s03, stirring the primary extract and an acid solvent at the temperature of 45-60 DEG C according to the mass ratio of 100: (5-7) for 30-35 minutes, standing and precipitating for 1 hour, and centrifugally separating to obtain a secondary extract; and S04, mixing and stirring the secondary extract and an alkaline solvent at the temperature of 45-60 DEG C according to the mass ratio of 100: (8-10) for 30-35 minutes, standing and precipitating for 1 hour, and centrifugally separating to obtain the zanthoxylum oil resin. Compared with the prior art, the acid and alkali purification process is arranged, so that the technical problems that the bitter taste of the extracted zanthoxylum oil resin is still obvious, the impurity removal process is relatively complex and the cost is relatively high in the prior art are solved.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to a refining process for a red prickly ash extract. Background Art

[0002] As an important spice, red pepper is widely used in food, seasoning and other fields. Pepper oil extract extracted from red pepper is favored by the market due to its unique flavor and bioactive ingredients. However, there are some urgent problems in the quality of red pepper oil extract, especially in removing bitterness.

[0003] In the existing red pepper oil extraction technology, most methods only focus on extracting the effective ingredients of pepper oil. Existing extraction schemes include mechanical pressing, solvent extraction, supercritical CO2 extraction, etc. However, the mechanical pressing method has a low extraction rate (4% to 6%), and the solvent extraction method has a very low extraction rate (8% to 12%) and is also accompanied by a large amount of wastewater. Supercritical extraction can greatly increase the extraction rate (15% to 18%). At the same time, in order to improve the purity and quality of the product, it is usually necessary to undergo multi-stage extraction and needs to be equipped with a molecular distillation process for purification. This process can ensure the product yield and quality, but the procurement cost of supercritical extraction equipment and molecular distillation equipment is relatively high.

[0004] At the same time, the pepper oleoresin extracted by the above process still has a distinct bitter taste, and the impurity removal process is relatively complicated and costly. Summary of the invention

[0005] The present invention aims to provide a refining process for red prickly ash extract, which is mainly used to solve the technical problems that the prickly ash oleoresin extracted in the existing process still has obvious bitterness, and the impurity removal process is relatively complicated and the cost is high.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A refining process for a red pepper extract comprises the following steps:

[0008] S01: preparing Zanthoxylum bungeanum oil extract;

[0009] S02: mixing the Zanthoxylum bungeanum oil extract and the salt water in a mass ratio of 1:3-4 for 30-35 minutes, standing for 3-5 hours, and separating the supernatant to obtain a primary extract;

[0010] S03: stirring the primary extract and the acidic solvent at a mass ratio of 100:5-7 at a temperature of 45-60° C. for 30-35 minutes, allowing to settle for 1 hour, and obtaining a secondary extract after centrifugation;

[0011] S04: Mix the secondary extract and the alkaline solvent at a mass ratio of 100:8-10 at a temperature of 45-60° C. for 30-35 minutes, let it stand for 1 hour, and obtain the prickly ash oleoresin after centrifugal separation.

[0012] Preferably, in step S01, the preparation method of the Zanthoxylum bungeanum oil extract is as follows: dry Zanthoxylum bungeanum is pretreated and then placed in a carbon dioxide supercritical extraction kettle for supercritical extraction to obtain the Zanthoxylum bungeanum oil extract.

[0013] Preferably, the pretreatment method of the dried pepper is as follows:

[0014] S11: mixing the dried red pepper shells with the washing solution and freezing the mixture until the salt water is completely frozen;

[0015] S12: thawing the frozen pepper and the salt water, and then centrifugally dehydrating the pepper;

[0016] S13: Freezing the dehydrated pepper again, and crushing the pepper into 60 mesh size after freezing.

[0017] Preferably, the washing liquid comprises the following components in parts by weight: 5-8 parts of sodium chloride, 100 parts of water, and 3-5 parts of 6% phosphoric acid aqueous solution.

[0018] Preferably, the mass ratio of the washing liquid to the red pepper shell is 1 to 2:1.

[0019] Preferably, in step S11, the freezing temperature is -18 to -20°C.

[0020] Preferably, the thawing in step S12 is gradient thawing, and the specific steps are as follows:

[0021] The frozen pepper and salt water are heated up to -4 to -2°C and kept warm for 20 to 25 minutes, then heated up to 0°C and kept warm for 40 to 50 minutes, and finally heated up to 4 to 6°C and kept warm for 10 to 15 minutes.

[0022] Preferably, in step S13, the dehydrated Zanthoxylum bungeanum is quickly frozen using liquid nitrogen.

[0023] Preferably, in step S02, the concentration of the brine is 5% to 6%.

[0024] Preferably, in step S03, the acidic solution is a 0.5% citric acid solution or a 3% phosphoric acid solution; in step S04, the alkaline solution is a 5% sodium bicarbonate solution or a 2% sodium carbonate solution.

[0025] Beneficial effects of this program:

[0026] (1) The effective components in the pepper oil are extracted by a supercritical extraction kettle. However, in the current process, the crude oil obtained by supercritical extraction contains many impurities. The crude oil is firstly washed with salt water to further remove water-soluble impurities in the crude oil and bitter substances remaining in the crude oil. Then, the pepper oil extract is acid-washed with an acid solution to further precipitate tannins. Then, the residual acid is neutralized by alkaline washing with an alkaline solution, and free fatty acids and phospholipid impurities are simultaneously saponified. Impurities in the pepper oil extract are removed to improve the quality of pepper oleoresin.

[0027] (2) In the entire extraction process of Zanthoxylum bungeanum oleoresin, the dried red Zanthoxylum bungeanum shells are soaked in a washing liquid and frozen, the purpose of which is to remove the bitterness of the Zanthoxylum bungeanum itself and a part of the water-soluble impurities through the salt water in the washing liquid. Through the freezing treatment, the plant cells of the Zanthoxylum bungeanum can be pierced by ice crystals, which promotes the dissolution of impurities in the Zanthoxylum bungeanum and at the same time can improve the extraction rate of the Zanthoxylum bungeanum oleoresin in the supercritical extraction stage; a 6% phosphoric acid aqueous solution is also added to the washing liquid, and the acidic environment can soften the plant cell wall and hydrolyze structural substances such as pectin, thereby accelerating the release of oleoresin from the cells.

[0028] (3) In step S12, the pepper and the washing liquid are gradually thawed to melt the ice crystals slowly, thereby preventing the thin-walled cells of the pepper containing bitter substances from rupturing on a large scale due to rapid expansion and contraction, resulting in a large amount of bitter substances being released, which affects the taste of the finished product.

[0029] (4) After being frozen and thawed once, the texture of the peppercorns is relatively soft, which is not conducive to crushing. The thawed peppercorns are quickly frozen, and the shells of the peppercorns are relatively brittle, which is convenient for the crusher to crush them into the required particle size.

[0030] (5) In the prior art, fresh pepper is usually used to extract pepper oleoresin because the pepper oleoresin in fresh pepper is easier to extract and has a higher content. However, fresh pepper is usually not easy to preserve and has a high storage cost. Dried pepper is easy to store, but its extraction rate is lower than that of fresh pepper (usually 5-8 percentage points lower). At the same time, the extracted oleoresin tastes more bitter than fresh pepper. The present process improves the traditional supercritical extraction process, pretreats the dried pepper and subsequently purifies the crude product, thereby increasing the pepper oleoresin extraction rate of the dried pepper and reducing the bitterness of the finished product, thereby improving the quality of the product.

[0031] (5) In order to ensure the quality of the extract, the existing supercritical extraction process usually requires multi-stage extraction and is equipped with molecular distillation equipment for purification. In this scheme, only one supercritical extraction is performed and the subsequent purification process is assisted. On the one hand, there is no need for high-cost molecular purification equipment to participate in the production. On the other hand, a high product yield can be guaranteed without multi-stage extraction, thereby reducing costs and increasing efficiency. DETAILED DESCRIPTION

[0032] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] Embodiment 1:

[0034] A refining process for a red pepper extract comprises the following steps:

[0035] S01: preparing a pepper oil extract, comprising the following steps:

[0036] S11: mixing the dried red pepper shells with the washing liquid in a mass ratio of 1:2 and freezing them at a freezing temperature of -18°C until the salt water is completely frozen, wherein the washing liquid comprises the following components in parts by weight: 5 parts of sodium chloride, 100 parts of water, and 3 parts of a 6% phosphoric acid aqueous solution;

[0037] S12: placing the frozen pepper and salt water in a thawing chamber (the temperature in the thawing chamber can be adjusted) for gradient thawing, the specific steps are as follows: heating the frozen pepper and salt water to -3°C and keeping them warm for 20 minutes, then heating them to 0°C and keeping them warm for 45 minutes, and finally heating them to 4°C and keeping them warm for 15 minutes; then centrifugally dehydrating the thawed pepper;

[0038] S13: using liquid nitrogen to quickly freeze the dehydrated peppercorns until the peppercorns are frozen and hardened, and then crushing the peppercorns into 60 mesh sizes;

[0039] S14: pre-treating the crushed pepper powder and then placing it in a carbon dioxide supercritical extraction kettle for supercritical extraction to obtain a pepper oil extract, wherein the extraction pressure is 28 MPa, the extraction temperature is 50° C., and the extraction time is 3 h; the separation pressure is 7 MPa, and the separation temperature is 45° C.;

[0040] S02: mixing the Zanthoxylum bungeanum oil extract and 5% saline in a mass ratio of 1:3 for 30 minutes, letting stand for 4 hours, and separating the supernatant to obtain a primary extract;

[0041] S03: The primary extract and a 3% phosphoric acid solution were stirred at a mass ratio of 100:5 at 50°C for 30 minutes, allowed to settle for 1 hour, and centrifuged to obtain a secondary extract;

[0042] S04: The secondary extract and 5% sodium bicarbonate solution were mixed and stirred at a mass ratio of 100:8 for 35 minutes, allowed to stand for 1 hour, and centrifuged to obtain Zanthoxylum bungeanum oleoresin.

[0043] Embodiment 2:

[0044] Different from Example 1, the washing liquid in step S11 includes the following components in parts by weight: 8 parts of sodium chloride, 100 parts of water, and 5 parts of 6% phosphoric acid aqueous solution.

[0045] Embodiment 3:

[0046] Different from Example 1, the 3% phosphoric acid solution in S03 is replaced by a 0.5% citric acid solution; and the 5% sodium bicarbonate solution in S04 is replaced by a 2% sodium carbonate solution.

[0047] Comparative Example 1:

[0048] The difference from Example 1 is that S01: the dried red pepper shells are crushed into a size of 60 mesh, the crushed pepper powder is pre-treated and then placed in a carbon dioxide supercritical extraction kettle for supercritical extraction to obtain a pepper oil extract, wherein the extraction pressure is 28 MPa, the extraction temperature is 50° C., and the extraction time is 3 h; the separation pressure is 7 MPa, and the separation temperature is 45° C.;

[0049] The remaining steps are consistent with those in Example 1.

[0050] Comparative Example 2:

[0051] Different from Example 1, in step S12, the frozen Sichuan pepper and salt water are not thawed by gradient thawing, but by direct thawing. The specific steps are: placing the frozen Sichuan pepper and salt water in a thawing bin at 4°C until the salt water and the Sichuan pepper are completely thawed.

[0052] Comparative Example 3:

[0053] Different from Example 1, the washing liquid includes the following components in parts by weight: 5 parts of sodium chloride and 100 parts of water.

[0054] Comparative Example 4:

[0055] The pepper oil extract prepared in step S01.

[0056] Measurement example 1:

[0057] The yields of Zanthoxylum bungeanum oleoresin in Examples 1-4 and Comparative Examples 1 and 2 are summarized in the following table:

[0058] Yield = weight of pepper oleoresin / weight of pepper raw material)*100%

[0059] Yield Example 1 27.3％ Example 2 26.5％ Example 3 25.8％ Comparative Example 1 10.7％ Comparative Example 2 15.6％ Comparative Example 3 19.5％

[0060] Table 1

[0061] in conclusion:

[0062] According to the results in Table 1, we can see that:

[0063] 1. Comparative Example 1 is close to the traditional supercritical carbon dioxide extraction process. After the pepper raw material is frozen, the yield of pepper oleoresin is higher than that of Comparative Example 1, which proves that freezing the raw material can significantly increase the yield of pepper oleoresin.

[0064] 2. The yield of Comparative Example 2 is significantly lower than that of Example 1, which proves that compared with gradient thawing, direct thawing causes greater damage to the raw material of Zanthoxylum bungeanum, affecting the extraction rate of Zanthoxylum bungeanum oleoresin;

[0065] 3. The yields of Examples 1-3 are lower than that of Comparative Example 3. It can be seen that adding an acidic solution to the washing solution during the freezing stage can further destroy the cell structure of the Zanthoxylum bungeanum raw material and help separate the Zanthoxylum bungeanum oleoresin.

[0066] Test Example 2:

[0067] The pepper oil products prepared in the above embodiments and comparative examples were subjected to sensory evaluation. The pepper oil was diluted to 2 degrees of numbing using soybean oil for evaluation. Three testers were invited to taste the diluted products of each embodiment and comparative example and evaluate them according to the evaluation criteria. The scoring results of the three testers were averaged and recorded in the following table after rounding off:

[0068] Evaluation criteria:

[0069] No bitterness: 0

[0070] Slightly bitter, not affecting consumption: 1

[0071] Obvious bitter taste, which then dissipates, and the eating experience is not good: 2

[0072] Very bitter, inedible: 3

[0073] Test items Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Bitterness intensity 0 0 0 1 2 0 2

[0074] Table 2

[0075] According to the results in Table 2, the bitterness of Examples 1-3 and Comparative Example 3 is weaker than that of Comparative Example 1, Comparative Example 2, and Comparative Example 4, which proves that the bitterness of Zanthoxylum bungeanum oleoresin can be significantly reduced after the freezing treatment in the early stage and the impurity removal in the later stage; and compared with the examples, Comparative Example 2 is significantly more bitter than the examples with gradient thawing because no gradient thawing is performed;

[0076] Among them, the bitterness intensity of the product in Comparative Example 4 is 2. It can be seen that if the extracted pepper oil extract is not purified in steps S02, S03, and S04, the product still has obvious bitterness.

[0077] In summary, in the preparation process of the embodiment, the raw material treatment (S01) in the front stage and the purification (S02, S03, S04) steps of the crude product work synergistically with each other to increase the yield of Zanthoxylum bungeanum oleoresin, reduce the bitterness of the product, and improve the product quality.

[0078] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A process for refining a red pepper extract, characterized in that: The steps include: S01: preparing Zanthoxylum bungeanum oil extract; S02: mixing the Zanthoxylum bungeanum oil extract and the salt water in a mass ratio of 1:3-4 for 30-35 minutes, standing for 3-5 hours, and separating the supernatant to obtain a primary extract; S03: stirring the primary extract and the acidic solvent at a mass ratio of 100:5-7 at a temperature of 45-60° C. for 30-35 minutes, allowing to settle for 1 hour, and obtaining a secondary extract after centrifugal separation; S04: Mix the secondary extract and the alkaline solvent at a mass ratio of 100:8-10 at a temperature of 45-60° C. for 30-35 minutes, let it stand for 1 hour, and obtain the prickly ash oleoresin after centrifugation.

2. The method for refining a red pepper extract according to claim 1, characterized in that: In step S01, the preparation method of the pepper oil extract is as follows: dry pepper is pretreated and then placed in a carbon dioxide supercritical extraction kettle for supercritical extraction to obtain the pepper oil extract.

3. A process for refining a red prickly ash extract according to claim 2, characterized in that: The pretreatment method of the dried Chinese prickly ash is as follows: S11: mixing the dried red pepper shells with the washing solution and freezing the mixture until the salt water is completely frozen; S12: thawing the frozen pepper and the salt water, and then centrifugally dehydrating the pepper; S13: Freezing the dehydrated pepper again, and crushing the pepper into 60 mesh size after freezing.

4. A process for refining a red prickly ash extract according to claim 3, characterized in that: The washing liquid comprises the following components in parts by weight: 5-8 parts of sodium chloride, 100 parts of water, and 3-5 parts of 6% phosphoric acid aqueous solution.

5. The process for refining a red prickly ash extract according to claim 4, characterized in that: The mass ratio of the washing liquid to the red pepper shell is 1 to 2:

1.

6. A process for refining a red prickly ash extract according to claim 5, characterized in that: In the step S11, the freezing temperature is -18 to -20°C.

7. The process for refining a red pepper extract according to claim 6, characterized in that: The thawing in step S12 is gradient thawing, and the specific steps are as follows: The frozen pepper and salt water are heated up to -4 to -2°C and kept warm for 20 to 25 minutes, then heated up to 0°C and kept warm for 40 to 50 minutes, and finally heated up to 4 to 6°C and kept warm for 10 to 15 minutes.

8. The process for refining a red pepper extract according to claim 7, characterized in that: In the step S13, the dehydrated pepper is quickly frozen using liquid nitrogen.

9. The process for refining a red pepper extract according to claim 8, characterized in that: In step S02, the concentration of the brine is 5% to 6%.

10. A process for refining a red pepper extract according to claim 9, characterized in that: In step S03, the acidic solution is a 0.5% citric acid solution or a 3% phosphoric acid solution; in step S04, the alkaline solution is a 5% sodium bicarbonate solution or a 2% sodium carbonate solution.