Green pepper powder processing technology

Abstract

The invention provides a green pepper powder processing technology which comprises the following steps: S1, raw material treatment: taking fresh green peppers with the maturity of 6-8 as a raw material, and removing stems, threshing and cleaning the green peppers; s2, performing fixation treatment: performing fixation treatment on the cleaned green peppers; s3, performing fragrance locking treatment: adding the green pepper subjected to fixation into a trehalose solution, soaking at normal temperature for 8-12 minutes, and then cleaning and draining; and S4, drying and crushing treatment: performing freezing-far infrared combined drying treatment on the treated green pepper, and grinding into powder to obtain the green pepper powder. Trehalose is adopted as an aroma locking agent, and green peppers are subjected to synergistic treatment in a combined drying mode, so that the natural green color of the green peppers can be effectively kept, flavor loss can be reduced, the retention rate of core flavor and functional components is increased to about 45%, and the green peppers are free of any peculiar smell and excellent in quality.

Description

Technical Field

[0001] This invention belongs to the field of agricultural product processing technology, and specifically relates to a green pepper powder processing technology. Background Technology

[0002] Pepper (Piper nigrum L.) is a perennial woody climbing vine belonging to the Piperaceae family, and is known as the "King of Spices." It is mainly distributed in tropical and subtropical regions.

[0003] Commercially available pre-processed pepper products are mainly black pepper and white pepper, but both have significant drawbacks: black pepper suffers severe nutrient loss during processing; while the traditional water-soaking method used for white pepper easily leads to excessive levels of microorganisms (such as E. coli) and produces a putrid odor. These processes result in a significant difference between the finished product and fresh pepper in terms of color (losing the bright green of fresh pepper), flavor (reduced spiciness), and safety.

[0004] Green peppercorns are the unripe fruits of the pepper plant. After processing, they possess a unique aroma and a mild spiciness, and are widely used in seasonings, food, and the catering industry. Traditional green peppercorn processing typically involves steps such as washing, blanching, drying, and grinding. However, current technologies still have many shortcomings in preserving the natural color and aroma of green peppercorns, as well as in controlling energy consumption and production costs.

[0005] First, regarding color preservation, the chlorophyll in green peppercorns is easily degraded or browned during processing due to factors such as heat, light, and oxygen, resulting in a yellowish or darkened color in the finished product, losing its vibrant green visual quality and affecting its market value. Second, regarding flavor retention, traditional hot air drying or baking processes involve high temperatures and long processing times, easily causing the loss of volatile flavor compounds in green peppercorns. They may also produce a burnt odor due to overheating, severely impacting the product's pure flavor. Furthermore, some existing technologies add chemical color-fixing agents or synthetic flavorings for color fixation or aroma preservation, potentially posing food safety risks and failing to meet modern consumers' pursuit of natural and healthy foods. Finally, from a production process economic perspective, traditional drying methods (such as single hot air drying) often have high energy consumption, low drying efficiency, and high equipment maintenance costs, hindering large-scale production and cost control. Therefore, there is an urgent need to develop a new green peppercorn powder processing technology that can effectively maintain the natural bright green color of green peppercorns, maximize the retention of its original flavor, ensure food safety, and has low energy consumption, suitable for efficient industrial production. Summary of the Invention

[0006] Therefore, the purpose of this invention is to provide a green pepper powder processing technology that can effectively maintain the natural green color of green pepper, retain its original flavor to the maximum extent, ensure food safety, consume less energy, and is suitable for efficient industrial production.

[0007] The above-mentioned objective of this invention is achieved through the following technical solution: This invention provides a green pepper powder processing technology, including the following steps: S1, raw material processing: using fresh green peppers with a maturity of 6-8 as raw materials, the green peppers are destemmed, threshed, and washed; S2, blanching treatment: blanching the washed green peppers; S3, aroma locking treatment: adding the blanched green peppers to a trehalose solution, soaking at room temperature for 20-40 minutes, then washing and draining; S4, drying and pulverizing treatment: subjecting the treated green peppers to freeze-far-infrared combined drying treatment, and grinding them into powder to obtain green pepper powder.

[0008] In one optional embodiment, the concentration of the trehalose solution in step S3 is 7-13%. In one optional embodiment, the ratio of green peppercorns to the fragrance-locking agent in step S3 is 1g:3mL. In one optional embodiment, the soaking time in step S3 is 30 minutes. In one optional embodiment, the freeze-drying process in step S4 is as follows: the green peppercorns are first frozen at -80°C for 8-12 hours, then transferred to a freeze dryer for 12-15 hours, and then placed in a far-infrared drying oven at 45-75°C and 1200-1500W until the moisture content is below 5%.

[0009] The present invention has the following beneficial effects: By using trehalose as a flavor-locking agent and combining drying with other methods to synergistically process green pepper, the present invention can not only effectively maintain the natural green color of green pepper, but also reduce flavor loss. The retention rate of its core flavor and functional components is increased to about 45%, with no off-odor and excellent quality. The flavor-locking agent used is food-grade, non-toxic and harmless, and has high safety. The production process has low energy consumption, low maintenance costs, high output, and good product quality. Attached Figure Description

[0010] Figure 1 The color of the green pepper powder obtained in Example 1 of this invention.

[0011] Figure 2 The color of the green pepper powder obtained in Comparative Example 1 of this invention is shown.

[0012] Figure 3 The color of the green pepper powder obtained in Comparative Example 10 of the present invention is shown.

[0013] Figure 4 The color of the green pepper powder obtained in Comparative Example 11 of the present invention is shown. Detailed Implementation

[0014] The present invention will be further illustrated below with reference to specific embodiments, but these embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in this technical field. Unless otherwise specified, the reagents and materials used in the following embodiments are commercially available.

[0015] Example 1 A green pepper powder processing method includes the following steps: S1. Raw Material Processing: Using fresh green peppercorns with a maturity of 6-8, remove the stems and seeds, and wash them with clean water at least twice. S2. Blanching: Blanch the washed green peppercorns at 100°C for 5 minutes. S3. Aroma Locking: Add the blanched green peppercorns to a 10% trehalose solution at a ratio of 1g:3mL, soak at room temperature for 30 minutes, then wash with clean water at least twice. Drain until no water remains on the surface of the peppercorns. S4. Drying and Grinding: Freeze the drained green peppercorns at -80°C for 8 hours, then freeze them in a freeze dryer for 12 hours. Next, place the sample in a far-infrared drying oven (processing temperature 60°C, input power 1200 W) until the moisture content is below 5%. Remove and grind into powder to obtain green pepper powder. The obtained green pepper powder is as follows: Figure 1 As shown.

[0016] Example 2 A green pepper powder processing method includes the following steps: S1. Raw Material Processing: Using fresh green peppercorns with a maturity of 6-8, remove the stems and seeds, and wash them with clean water at least twice. S2. Blanching: Blanch the washed green peppercorns at 100°C for 5 minutes. S3. Aroma Locking: Add the blanched green peppercorns to a 13% trehalose solution at a ratio of 1g:3mL, soak at room temperature for 20 minutes, then wash with clean water at least twice. Drain until no water flows from the surface of the peppercorns. S4. Drying and Grinding: Freeze the drained green peppercorns at -80°C for 8 hours, then freeze them in a freeze dryer for 12 hours. Next, place the sample in a far-infrared drying oven (processing temperature 60°C, input power 1200 W) until the moisture content is below 5%. Remove and grind into powder to obtain green peppercorn powder.

[0017] Example 3 A green pepper powder processing method includes the following steps: S1. Raw Material Processing: Using fresh green peppercorns with a maturity of 6-8, remove the stems and seeds, and wash them with clean water at least twice. S2. Blanching: Blanch the washed green peppercorns at 100°C for 5 minutes. S3. Aroma Locking: Add the blanched green peppercorns to a 7% trehalose solution at a ratio of 1g:3mL, soak at room temperature for 40 minutes, then wash with clean water at least twice. Drain until no water flows from the surface of the peppercorns. S4. Drying and Grinding: Freeze the drained green peppercorns at -80°C for 8 hours, then freeze them in a freeze dryer for 12 hours. Next, place the sample in a far-infrared drying oven (processing temperature 60°C, input power 1200 W) until the moisture content is below 5%. Remove and grind into powder to obtain green peppercorn powder.

[0018] Compare with Example 1 The difference between this comparative example and Example 1 is that the trehalose solution is replaced with water; the remaining ingredients and steps are the same as in Example 1. The resulting green pepper powder is as follows: Figure 2 As shown.

[0019] Compare with Example 2 The difference between this comparative example and Example 1 is that the trehalose solution is replaced with maltodextrin, while the other raw material composition and steps are the same as in Example 1.

[0020] Compare with Example 3 The difference between this comparative example and Example 1 is that the trehalose solution is replaced with inulin, while the other raw material composition and steps are the same as in Example 1.

[0021] Compare with Example 4 The difference between this comparative example and Example 1 is the concentration of the trehalose solution. The concentration of the trehalose solution in this comparative example is 5%, while the composition of the other raw materials and steps are the same as in Example 1.

[0022] Compare with Example 5 The difference between this comparative example and Example 1 is the concentration of the trehalose solution. The concentration of the trehalose solution in this comparative example is 15%, while the composition of the other raw materials and the steps are the same as in Example 1.

[0023] Compare with Example 6 The difference between this comparative example and Example 1 is the concentration of the trehalose solution. The concentration of the trehalose solution in this comparative example is 20%, while the composition of the other raw materials and the steps are the same as in Example 1.

[0024] Compare with Example 7 The difference between this comparative example and Example 1 is the soaking time. The soaking time in this comparative example is 15 minutes. The other raw material composition and steps are the same as in Example 1.

[0025] Compare with Example 8 The difference between this comparative example and Example 1 is the soaking time. The soaking time in this comparative example is 45 minutes. The other raw material composition and steps are the same as in Example 1.

[0026] Compare with Example 9 The difference between this comparative example and Example 1 is the soaking time. The soaking time in this comparative example is 60 minutes. The other raw material composition and steps are the same as in Example 1.

[0027] Compare with Example 10 The difference between this comparative example and Example 1 lies in the drying method. This comparative example uses only a single vacuum freeze-drying method; the remaining raw material composition and steps are the same as in Example 1. The resulting green pepper powder is as follows: Figure 3 As shown.

[0028] Compare with Example 11 The difference between this comparative example and Example 1 lies in the drying method. This comparative example uses only far-infrared drying, while the remaining raw material composition and steps are the same as in Example 1. The resulting green pepper powder is as follows: Figure 4 As shown.

[0029] Test case

[0030] I. Flavor Measurement (I) Effects of different flavor-locking agents on the flavor of pepper powder The relative content of volatile substances in green pepper powder was determined by solid-phase microextraction-gas chromatography-mass spectrometry.

[0031] Sample preparation: Accurately weigh 500 mg of each sample (Example 1, Comparative Examples 1-3), place them in a 20 mL headspace vial, add 1.0 g of sodium chloride, and seal. Extraction conditions: Preheat the headspace vial at 60°C for 5 minutes, then insert a 120 μm DVB / CWR / PDMS extraction fiber, ensuring continuous contact between the fiber and the sample headspace region at a constant temperature of 60°C for 15 minutes to achieve efficient adsorption and enrichment of volatile organic compounds. Chromatographic conditions: DB-5MS capillary column (30 m × 0.25 mm × 0.25 μm, Agilent J&W Scientific, Folsom, CA, USA), carrier gas high-purity helium (purity not less than 99.999%), constant flow rate 1.2 mL / min, injection port temperature 250 °C, solvent delay 3.5 min. Temperature program: 40 °C for 3.5 min, then ramp to 100 °C at 10 °C / min, then to 180 °C at 7 °C / min, and finally to 280 °C at 25 °C / min, held for 5 min. Mass spectrometry conditions: Electron impact ionization (EI) source, ion source temperature 230 °C, quadrupole temperature 150 °C, mass spectrometer interface temperature 280 °C, electron energy 70 eV, scan mode selected ion detection (SIM), precise qualitative and quantitative ion scanning (GB 23200.8-2016). Data analysis: An independent database was established by integrating multi-species metabolite information, literature data, standards, and retention indices. Each record includes a preset retention time, one quantitative ion, and 2-3 qualitative ions. When the detected retention time matches the database reference value, and all preset ions are present in the background subtraction spectrum, the compound identification result is confirmed in selected ion monitoring mode. A total of 102 key flavor compounds (rOAV ≥1) were screened out, and the detection results are shown in Table 1.

[0032] Table 1. Effects of different aroma-locking treatments on pepper flavor.

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[0038]

[0039] The results showed that, compared with control group 1, the flavor of green peppers treated with aroma-locking agents (Example 1, control group 2, and control group 3) was improved to a certain extent. Among them, the green peppers treated with trehalose (Example 1) had the highest total relative content of volatile compounds (20751.26 μg / g ~ 24325.80 μg / g), which was higher than that of control group 1 (18380.09 μg / g ~ 20273.60 μg / g), indicating that it had an aroma-locking effect, and the effect was relatively significant. The effects of maltodextrin and inulin were second, with total volatile contents of 18292.58 μg / g ~ 24061.43 μg / g and 15801.60 μg / g ~ 20661.35 μg / g, respectively. As can be seen from Table 1 above, the addition of trehalose not only comprehensively increases the content of key flavor compounds in green pepper powder, significantly enhancing its aroma intensity, but also reconstructs its flavor profile. While retaining the classic herbal and woody base, it injects richer layers of fruit and floral aromas, and makes the signature spicy aroma purer and more powerful. At the same time, the process also promotes the development of pleasant roasted nut aromas and, by effectively suppressing some undesirable flavor compounds, makes the overall flavor purer, fuller, and more harmonious.

[0040] (II) Effects of different concentrations of trehalose solution on the flavor of pepper powder The experimental procedure was the same as in the section “(I) Effect of different flavor-locking agents on the flavor of pepper” above, except that Control Example 1, Control Example 2 and Control Example 3 were replaced with Control Example 4, Control Example 5 and Control Example 6 respectively. The test results are shown in Table 2.

[0041] Table 2 Effect of trehalose solution concentration on pepper flavor

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[0048] The results indicate that the volatile component content is best preserved after soaking in a 10% trehalose solution for 30 minutes. When the concentration is below or above 10%, most flavor components (volatile component content) tend to decrease.

[0049] (III) The effect of different soaking times on the flavor of pepper powder The experimental procedure was the same as in the section “(I) Effect of different flavor-locking agents on the flavor of pepper” above, except that Control Example 1, Control Example 2 and Control Example 3 were replaced with Control Example 7, Control Example 8 and Control Example 9 respectively. The test results are shown in Table 3.

[0050] Table 3. Effects of different soaking times on the flavor of pepper powder

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[0057] The above results indicate that soaking in trehalose solution for 30 minutes resulted in a higher retention of volatile components. Soaking for too short a time (e.g., 15 minutes) prevents trehalose from fully penetrating the pepper powder particles, thus limiting its protective effect on volatile components. In this case, volatile components (such as terpenes, aldehydes, and ketones) are more likely to volatilize or oxidize during subsequent processing or storage, leading to a diluted flavor and weakened aroma. Soaking for too long (e.g., more than 30 minutes) may cause trehalose to be excessively adsorbed onto the surface of the pepper powder or penetrate into its interior, forming a "protective film" that hinders the release of flavor compounds, resulting in a dull and unnatural flavor. Furthermore, excessive soaking time may cause some volatile components to react with trehalose or other components (such as Maillard reaction, caramelization, etc.), leading to the destruction or transformation of some aroma components, thereby reducing the purity of the flavor. Therefore, a soaking time of 30 minutes results in a richer and more mellow flavor for the pepper powder.

[0058] (iv) Effects of single drying and combined drying on pepper flavor The experimental procedure was the same as in the section “(I) Effect of different flavor-locking agents on the flavor of pepper powder” above, except that the test samples were Example 1, Control Example 10 and Control Example 11, and the test results are shown in Table 4.

[0059] Table 4. Effects of single drying and combined drying on pepper flavor.

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[0064]

[0065] The results indicate that the combined drying process preserves a higher content of volatile components. This is because freeze-drying effectively retains heat-sensitive flavor compounds in pepper powder at low temperatures, but the vacuum stage removes most of these flavor compounds, leading to a significant reduction in content. Far-infrared drying, on the other hand, rapidly removes moisture, reduces drying time, and avoids flavor degradation caused by prolonged exposure to high temperatures. The synergistic effect of both processes not only improves drying efficiency but also minimizes damage to volatile components, thus more effectively preserving the original flavor of the pepper powder.

[0066] II. Piperine Determination The piperine content was determined according to the method specified in GB / T 17528-2009 "Determination of Piperine Content by High Performance Liquid Chromatography". Examples 1, 1, 2, 3, 10, and 11 were used as test samples. 0.5 g of each sample was weighed and extracted with 20 mL of chromatographic grade ethanol at 50°C using an ultrasonic cleaner for 18 minutes. After ultrasonic treatment, 0.1 mL of the supernatant was accurately transferred to a 10 mL amber volumetric flask. The sample was then diluted with ethanol at a ratio of 1:100, filtered through a 0.22 μm filter membrane, and quantitative analysis was performed using HPLC. The content was calculated using the external standard method. The piperine content in each test sample is shown in Table 5 below.

[0067] Table 5. Effects of different treatments on piperine content

[0068] The above results indicate that the piperine content of green pepper powder in Control Example 2 (treated with 10% maltodextrin-freeze-far-infrared drying) and Control Example 3 (treated with 10% inulin-freeze-far-infrared drying) is similar to that in Control Example 1 (treated with no flavor-locking agent-freeze-far-infrared drying), with no significant difference. The highest piperine content was 39.97 mg / g (Control Example 2), 40.6 mg / g (Control Example 3), and 39.12 mg / g, respectively. mg / g (Comparative Example 1); while the piperine content of green pepper powder in Example 1 (treated with 10% trehalose-freeze combined with far-infrared drying) reached the highest of 44.7 mg / g, indicating that when freeze-drying is carried out simultaneously, using trehalose as a flavor-locking agent can improve the yield of piperine, the core flavor compound of pepper, compared with not using any flavor-locking agent or using maltodextrin or inulin; the highest piperine content of Comparative Example 10 (treated with 10% trehalose-vacuum freeze-drying) and Comparative Example 11 (treated with 10% trehalose-far-infrared drying) was 39.60 mg / g and 32.81 mg / g, respectively, which were 5.1 mg / g and 11.89 mg / g lower than that of Example 1, respectively, indicating that when trehalose is used as a flavor-locking agent, only freeze-drying combined with far-infrared drying can improve the yield of piperine. Therefore, only by using trehalose as a flavor-locking agent to treat pepper, combined with freeze-drying and far-infrared drying, can the yield of piperine be improved and the color and flavor of pepper be preserved. The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

Claims

1. A green pepper powder processing method, characterized in that, Includes the following steps: S1. Raw material processing: Use fresh green peppercorns with a maturity of 6-8 as raw materials. Remove the stems and seeds from the green peppercorns and wash them. S2. Blanching: Blanch the washed green peppercorns. S3. Fragrance-locking treatment: Add the blanched green peppers to the trehalose solution, soak at room temperature for 8-12 minutes, then rinse and drain. S4. Drying and Grinding Process: The processed green peppers are subjected to freeze-drying and far-infrared combined drying, and then ground into powder to obtain green pepper powder.

2. The green pepper powder processing method according to claim 1, characterized in that, In step S3, the concentration of the trehalose solution is 7-13%.

3. The green pepper powder processing method according to claim 1, characterized in that, In step S3, the ratio of green pepper to trehalose solution is 1g:3mL.

4. The green pepper powder processing method according to claim 1, characterized in that, In step S3, the soaking time is 30 minutes.

5. The green pepper powder processing method according to claim 1, characterized in that, In step S4, the freeze-far-infrared combined drying process is as follows: green peppers are first frozen in a refrigerator at -80°C for 8 to 12 hours, then transferred to a freeze dryer for 12 to 15 hours, and then placed in a far-infrared drying oven at a temperature of 45 to 75°C and a power of 1200 to 1500W until the moisture content is less than 5%.

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