A method for preserving zanthoxylum bungeanum fruits

Abstract

The application provides a Zanthoxylum bungeanum fruit preservation method, and relates to the technical field of fruit preservation.The Zanthoxylum bungeanum fruit preservation method comprises the steps of removing impurities, soaking and cleaning, steam fixation, soaking and cooling, air drying, sealing and packaging, low-temperature storage and the like.The Zanthoxylum bungeanum fruit preservation method can avoid the loss of special flavor substances of Zanthoxylum bungeanum, realize the uninterrupted supply of fresh Zanthoxylum bungeanum all the year round, solve the problems of preservation and quality guarantee after the large-scale cultivation of Zanthoxylum bungeanum, effectively coordinate the contradictions of large-scale, ecological and high-quality in the process of ecological industry development, and has strong practical application value.

Description

Technical Field

[0001] This invention relates to the field of fruit preservation technology, and in particular to a method for preserving Sichuan pepper fruits. Background Technology

[0002] Sichuan pepper (Zanthoxylum bungeanum Maxim.) is a plant belonging to the genus Zanthoxylum in the Rutaceae family. Its fruit, due to its rich aroma and unique numbing sensation, is widely used as a raw material or additive in the food, medicine, health, and chemical industries. The aroma and numbing sensation of Sichuan pepper mainly come from the volatile oils and oil cells in its pericarp. The volatile oils primarily contain limonene, β-pinene, α-pinene, β-geranyne, citral, and citric acid, while the oil cells mainly contain xanthophylline, xanthophyllin, xanthophyllin, and xanthophyllotoxin. These substances not only determine the flavor characteristics of Sichuan pepper but also possess antibacterial, antioxidant, anti-inflammatory, analgesic, and anthelmintic physiological activities, which are beneficial to human health.

[0003] However, the aroma and numbing properties of Sichuan peppercorns are highly unstable and easily degraded or spoiled by factors such as temperature, humidity, light, oxygen, and microorganisms, leading to a decline in quality and a shortened shelf life. Therefore, effectively maintaining the freshness and flavor of Sichuan peppercorns is a key technical issue in their processing and storage.

[0004] Currently, the processing and storage of Sichuan pepper mainly involve the following methods:

[0005] Air-drying method: This is the most traditional method of processing Sichuan peppercorns. Freshly picked peppercorns are naturally air-dried under ventilated and shaded conditions, and then packaged and stored. This method is simple to operate and inexpensive, but it takes a long time to air-dry, is easily contaminated during the drying process, and results in peppercorns with a dull color, significant loss of aroma and numbing flavor, and a tendency to mold and spoil.

[0006] Hot air drying: This is a commonly used method for processing Sichuan peppercorns. Freshly picked peppercorns are artificially dried in a hot air dryer before being packaged and stored. This method can shorten drying time, reduce contamination, and preserve the color and flavor of the peppercorns. However, the drying effect is heavily influenced by temperature. Excessively high or uneven temperatures can cause the volatile oils and oil cells in the peppercorns to rupture, resulting in a loss of aroma and numbing sensation. It also increases energy consumption and costs.

[0007] Freezing method: This is a relatively advanced method for processing Sichuan peppercorns. Freshly harvested peppercorns undergo pretreatment such as washing, enzyme inactivation, and rapid cooling before being quickly frozen in a freezer at a temperature below -18°C. They are then packaged and stored. This method maximizes the preservation of freshness and flavor, extending shelf life. However, it requires sophisticated freezing equipment and storage conditions. The freezing and thawing process can easily alter the structure and texture of the peppercorns. Frozen peppercorns are also more susceptible to absorbing off-odors, and freezing and transportation costs are relatively high.

[0008] Therefore, it is evident that the common processing and storage methods for Sichuan pepper each have their own advantages and disadvantages, but none can fully meet the preservation requirements of Sichuan pepper. Furthermore, the following problems also commonly exist in the field of Sichuan pepper preservation:

[0009] Sichuan peppercorns have a short shelf life and are prone to spoilage. Existing technologies have shortcomings in post-harvest storage and low-temperature preservation, resulting in significant damage to the peppercorn pericarp and oil cells. This leads to rapid loss of aroma and numbing properties, making them susceptible to spoilage and shortening their shelf life. Therefore, Sichuan peppercorn preservation technology must focus not only on developing preservation processing parameters but also on ensuring seamless integration between the field and the consumer end.

[0010] The core quality of Sichuan peppercorns has declined. Inadequate control over parameters such as temperature, humidity, and time during the processing of fresh Sichuan peppercorns has led to a decrease in core quality, impacting their applications in food, medicine, health products, and chemicals.

[0011] High impurity content in Sichuan peppercorns negatively impacts their storage performance. Current techniques for producing Sichuan peppercorn oil are insufficient in removing impurities such as petioles, inferior peppercorns, and dust. These impurities undergo chemical and biological reactions in a sealed environment, affecting the storage of high-quality Sichuan peppercorns. Typically, the peppercorns begin to spoil after 3-4 months of storage, resulting in significant economic losses.

[0012] Sichuan peppercorns have a high moisture content in their pericarps, resulting in a short shelf life. Due to factors such as prolonged soaking, delayed air-drying, and improper temperature control, current technologies are inadequate in controlling the moisture content of the peppercorns. This leads to a soft and sticky pericarp that is easily broken under conditions of stacking, fermentation, and compression, directly impacting storage effectiveness. Consequently, the resulting preserved peppercorns suffer from problems such as short shelf life, difficulty in large-scale utilization, and low market competitiveness.

[0013] These existing technological limitations restrict the industrialization and market expansion of Sichuan pepper, and also affect its food safety and quality assurance. Therefore, there is an urgent need to develop a new Sichuan pepper preservation technology that can effectively extend its shelf life, maintain its aroma and numbing flavor, reduce impurities, improve its quality and value, and meet consumer needs and expectations. Summary of the Invention

[0014] To address the aforementioned problems, this invention provides a method for preserving Sichuan pepper fruits. This method can prevent the loss of their unique flavor compounds, ensuring a continuous year-round supply of fresh Sichuan pepper. It can solve the problems of preservation and quality maintenance after large-scale cultivation of Sichuan pepper, and can effectively coordinate the contradictions of large-scale, ecological, and high-quality development in the process of ecological industry development. It has strong practical application value.

[0015] The method for preserving Sichuan pepper fruits according to the present invention includes the following steps:

[0016] S1. After the peppercorns are harvested, the leaves, petioles and impurities are removed first, and then they are transported and temporarily stored under low temperature conditions.

[0017] S2. Soak and wash the fresh peppers to remove any new impurities generated during the washing process;

[0018] S3. Steam the soaked and cleaned peppercorns to kill the green color.

[0019] S4. After blanching, quickly soak the peppercorns in water to cool them down, and then air dry the surface moisture of the fruits.

[0020] S5. After the pepper fruits are air-dried, they should be sealed in packaging and stored and transported under low-temperature conditions.

[0021] Furthermore, the transport temperature is 0–10°C, and the temporary storage temperature is 0–5°C.

[0022] Furthermore, the harvesting, transportation, and temporary storage time shall not exceed 7 hours. Preferably, the harvesting, transportation, and temporary storage time shall not exceed 5 hours.

[0023] Furthermore, the soaking and cleaning is carried out in tap water, purified water, deionized water, or distilled water.

[0024] Furthermore, the weight ratio of the Sichuan pepper fruit to water is 1:45 to 55.

[0025] Furthermore, appropriate stirring is performed during the soaking and cleaning process.

[0026] Furthermore, the soaking and cleaning time is 2 to 3 minutes.

[0027] Furthermore, during the steam fixation process, the steam flow rate is 0.45–0.55 t / h, the fixation temperature is 76℃–82℃, and the fixation time is 4–4.5 min.

[0028] Furthermore, the soaking and cooling time is 70-80 seconds, and the drying time is controlled to be 25-30 seconds.

[0029] Furthermore, the sealed packaging specification is 250g / bag. Repackaging into smaller bags prevents the Sichuan peppercorns from spoiling after thawing at the market due to delayed consumption.

[0030] Furthermore, the storage temperature is -18℃ to -15℃, and the storage is kept sealed during the storage process.

[0031] Furthermore, the transport temperature is 0℃~10℃, and the transport time is 3~5 days.

[0032] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0033] 1. This invention, through strict control of parameters such as temperature, soaking, and air drying during the preservation of fresh Sichuan peppercorns, greatly delays the reaction of flavor substances and other chemical substances in the peppercorns, maintains the key quality substances such as aroma and numbing sensation, and increases the shelf life of Sichuan peppercorns by more than 100%.

[0034] 2. The fresh peppers prepared by this invention have a low probability of spoilage and extremely low raw material loss, thereby increasing the yield of pepper products and improving economic benefits.

[0035] 3. By extending the shelf life of Sichuan peppercorns and simplifying and reducing the difficulty of product preservation and transportation, this invention greatly improves the shelf life of fresh peppercorns, better meets the diverse needs of different consumers, ensures an uninterrupted supply of high-quality fresh peppercorns throughout the year, facilitates the diversified utilization of Sichuan peppercorns, helps to further develop the value of Sichuan peppercorns, and promotes the realization of the value of ecological products.

[0036] 4. Each step of this invention has a short processing time, and through mechanization and intelligentization, effective connections are achieved between different stages, thus shortening processing time, improving processing efficiency, and facilitating large-scale production. During the pepper harvesting season, it can meet the practical needs of large quantities of pepper and urgent processing demands, and has high value for widespread application. Detailed Implementation

[0037] This invention provides a method for preserving Sichuan pepper fruits, specifically including the following steps:

[0038] S1. After the peppercorns are harvested, the leaves, petioles and impurities are removed first, and then they are transported and temporarily stored under low temperature conditions.

[0039] S2. Soak and wash the fresh peppers to remove any new impurities generated during the washing process;

[0040] S3. Steam the soaked and cleaned peppercorns to kill the green color.

[0041] S4. After blanching, quickly soak the peppercorns in water to cool them down, and then air dry the surface moisture of the fruits.

[0042] S5. After the pepper fruits are air-dried, they should be sealed in packaging and stored and transported under low-temperature conditions.

[0043] In one embodiment, the transport temperature is 0–10°C, and the temporary storage temperature is 0–5°C.

[0044] In one embodiment, the harvesting, transportation, and temporary storage time does not exceed 7 hours.

[0045] In one embodiment, the harvesting, transportation, and temporary storage time does not exceed 5 hours.

[0046] In one embodiment, the soaking and cleaning is carried out in tap water, purified water, deionized water, or distilled water.

[0047] In one embodiment, the weight ratio of Sichuan pepper fruits to water during the soaking and washing process is 1:45 to 55.

[0048] In one embodiment, appropriate stirring is performed during the soaking and cleaning process.

[0049] In one embodiment, the soaking and cleaning time is 2 to 3 minutes.

[0050] This invention strictly limits the soaking time of Sichuan pepper fruits. The length of the soaking time determines the moisture content of the Sichuan pepper fruits. An inappropriate soaking time will significantly affect the flavor and shelf life of the Sichuan pepper fruits.

[0051] In one embodiment, the steam flow rate during the steam fixation process is 0.45–0.55 t / h, the fixation temperature is 76°C–82°C, and the fixation time is 4–4.5 min.

[0052] In one embodiment, the soaking and cooling time is 70-80 seconds, and the drying time is controlled to be 25-30 seconds.

[0053] This invention achieves rapid cooling of Sichuan pepper fruits through water cooling and air cooling. Simultaneously, this invention controls the cooling rate by strictly controlling the cooling time, avoiding problems such as difficulties in packaging due to excessively high temperatures and the resulting expansion and spoilage.

[0054] In one embodiment, the sealed packaging is in 250g / bag format. Repackaging into smaller bags prevents the Sichuan peppercorns from spoiling after thawing at the market due to delayed consumption.

[0055] In one embodiment, the storage temperature is -18°C to -15°C, and the storage is kept sealed during the storage process.

[0056] The reason for setting the storage temperature to -18℃ to -15℃ in this invention is that when the temperature is too high, it is difficult to inhibit the activity of microorganisms and the rate of chemical reaction, and the effect of refrigeration cannot be achieved; when the temperature is too low, more electrical energy will be consumed, the requirements for equipment will be higher, and there will be no significant impact on the effect.

[0057] In one embodiment, the transport temperature is 0℃~10℃, and the transport time is 3~5 days.

[0058] During product distribution, foam boxes with internal ice packs are used to maintain a temperature of 0-10℃, employing cold chain logistics to deliver the product to the customer within 3-5 days. Furthermore, the lightweight packaging allows for short-term consumption, preventing spoilage upon contact with air.

[0059] The technical solution provided by the present invention will be further described below with reference to the embodiments.

[0060] Example 1

[0061] After harvesting, the leaves, petioles, and impurities of the Sichuan peppercorns are first removed. They are then immediately stored in refrigerated trucks at a controlled temperature of 8°C to maintain freshness and are quickly transported to the fresh pepper processing workshop. The peppers are then temporarily stored in a cold storage facility at 5°C. The time from harvesting to processing should not exceed 6 hours. Practice has shown that if the interval is too long, the peel will soften and the fruit will spoil.

[0062] Fresh peppers and tap water were mixed at a weight ratio of 1:45. The mixture was intermittently and gently stirred with a stainless steel rake while impurities were removed with a stainless steel strainer for 2.5 minutes to clean and remove impurities from the peppers. The entire cleaning and impurity removal process was carried out in a cleaning tank (manufactured by Sichuan Energy-Saving Drying Equipment Co., Ltd., hereinafter referred to as the "tank"), with dimensions of 1.5m (length), 1.2m (width), and 1m (height). During cleaning, the conveyor belt at the bottom of the tank moved forward at a constant speed, and aeration was used to keep the tap water flowing, further achieving the purpose of mixing and cleaning. No additives or chemical reagents were used during the soaking and cleaning process to ensure an ecological processing method. During operation, care was taken to apply light and even pressure to prevent damage to the pepper peel; improper methods will reduce the shelf life of the peppers.

[0063] The Sichuan peppercorns were blanched in a blanching machine (produced by Sichuan Energy-Saving Drying Equipment Co., Ltd., hereinafter the same). The blanching process was as follows: steam flow rate was 0.5t / h, blanching temperature was 78℃, and blanching time was 4.5min.

[0064] After blanching, the Sichuan peppercorns are soaked in tap water for 75 seconds to cool them down, then dried with fans for 25 seconds. This combination of water and air cooling achieves the desired temperature reduction. The specific procedure involves filling a 3m long, 0.8m wide, and 0.7m high tank with tap water. A conveyor belt at the bottom of the tank maintains a thickness of 0.5-1cm for the Sichuan peppercorns, which move synchronously with the conveyor belt. A 1.5m air blower belt is then connected to the belt, along with three fans. The purpose of cooling after blanching is to prevent the peppercorns from expanding and spoiling due to excessively high temperatures after packaging.

[0065] After the Sichuan peppercorns are air-dried, they are sealed in 250g bags and stored in cold storage. The lightweight packaging is chosen so that customers can consume them within a shorter timeframe, preventing spoilage during use and ensuring the full expression of the peppercorn's flavor compounds.

[0066] Maintain the temperature inside the cold storage at -15℃ and keep it sealed for long-term storage.

[0067] The results showed that: (1) The shelf life of Sichuan pepper reached 12 months. (2) White spots appeared on the surface of the peel. Compared with the blackening and yellowing of the fruits in Comparative Examples 1-7, the Sichuan pepper fruits in this embodiment maintained their green color normally, achieving a better effect. (3) The peel of the Sichuan pepper fruits was relatively hard and would not break when lightly squeezed, thus maintaining its original shape. (4) The price was 28-30 yuan / kg, which is more economical than the fact that spoiled Sichuan pepper cannot be circulated in the market. (5) The aroma and numbing flavor were well preserved, with a loss rate of 10%.

[0068] The aroma index is expressed as volatile oil and tested in accordance with the national standard GB / T30385-2013. The numbing flavor substances are determined by high performance liquid chromatography.

[0069] Example 2

[0070] After harvesting, the leaves, petioles, and impurities of the Sichuan peppercorns are first removed. They are then immediately stored in refrigerated trucks at a controlled temperature of 5°C to maintain freshness and are quickly transported to the fresh pepper processing workshop. The peppercorns are then temporarily stored in a cold storage facility at 3°C. The time from harvesting to processing should not exceed 7 hours. In particular, during the harvesting process, it is crucial to prevent the oil cells from rupturing or being damaged, as this would significantly shorten the shelf life of the Sichuan peppercorns.

[0071] Fresh peppers and tap water are mixed at a weight ratio of 1:50. The mixture is intermittently and gently stirred with a stainless steel rake while impurities are removed with a stainless steel strainer. This process continues for 3 minutes to clean and remove impurities from the peppers. The entire cleaning and impurity removal process is carried out in a cleaning tank (manufactured by Sichuan Energy-Saving Drying Equipment Co., Ltd., hereinafter referred to as the "tank"), with dimensions of 1.5m (length), 1.2m (width), and 1m (height). During cleaning, the conveyor belt at the bottom of the tank moves forward at a constant speed, and aeration keeps the tap water flowing, further achieving the purpose of mixing and cleaning. No additives or chemical reagents are used during the soaking and cleaning process to ensure an ecological processing method. During operation, care should be taken to apply gentle and even pressure to prevent damage to the pepper peel; improper methods will reduce the shelf life of the peppers.

[0072] The Sichuan peppercorns were blanched in a blanching machine (produced by Sichuan Energy-Saving Drying Equipment Co., Ltd., hereinafter the same). The blanching process was as follows: steam flow rate was 0.55t / h, blanching temperature was 80℃, and blanching time was 4.25min.

[0073] After blanching, the Sichuan peppercorns are soaked in tap water for 80 seconds to cool them down, then dried with fans for 30 seconds. This combination of water and air cooling achieves the desired temperature reduction. The specific procedure involves filling a 3m long, 0.8m wide, and 0.7m high tank with tap water. A conveyor belt at the bottom of the tank maintains a thickness of 0.5-1cm for the Sichuan peppercorns, which move synchronously with the conveyor belt. A 1.5m air blower belt is then connected to the belt, along with three fans. The purpose of cooling after blanching is to prevent the peppercorns from expanding and spoiling due to excessively high temperatures after packaging.

[0074] After the Sichuan peppercorns are air-dried, they are sealed in 250g bags and stored in cold storage. The lightweight packaging is chosen so that customers can consume them within a shorter timeframe, preventing spoilage during use and ensuring the full expression of the peppercorn's flavor compounds.

[0075] Maintain the temperature inside the cold storage at -18℃ and keep it sealed for long-term storage to minimize the rate of chemical reactions.

[0076] The results showed that: (1) The shelf life of Sichuan pepper reached 12 months. (2) Many white spots appeared on the surface of the peel, which was still green and did not turn black or yellow, thus maintaining the quality characteristics and advantages of green Sichuan pepper (Sichuan pepper belongs to the green Sichuan pepper series). (3) The peel of the Sichuan pepper fruit was relatively hard and would not break when lightly squeezed, thus maintaining its original shape. (4) The price was 26-28 yuan / kg, which is more economical than spoiled Sichuan pepper that cannot be circulated in the market. (5) The aroma and numbing flavor were well preserved, with a loss rate of 8%.

[0077] Comparative Example 1

[0078] Same as Example 1, except that the time from harvesting to processing is 12 hours.

[0079] The results showed that: (1) Sichuan pepper has a shelf life of only 6 months. (2) Before processing, the color of Sichuan pepper tends to turn from green to black, the sensory appearance deteriorates, and the loss rate of aroma and numbing flavor is 17%. (3) Due to long-term exposure to air, the oil cells of Sichuan pepper begin to turn black and the pericarp softens, affecting the quality of fresh peppers in later processing. This indicates that the time from harvesting to processing should not be too long, and labor should be arranged reasonably during the Sichuan pepper harvesting season.

[0080] Comparative Example 2

[0081] Same as Example 1, except that the soaking and cleaning time is 6 minutes.

[0082] The results showed that: (1) Due to the increased water content of Sichuan pepper fruits, the shelf life of Sichuan pepper was only 4-5 months. (2) The pericarp of Sichuan pepper fruits was relatively soft and would break easily when lightly squeezed, leading to rapid degradation and volatilization of aroma and numbing substances, with a loss rate of 23%. (3) The oil cells after storage were not white, but mostly yellow, resulting in a lower sensory evaluation grade. This indicates that maintaining a reasonable soaking and washing time can improve the shelf life and shelf life of fresh peppers.

[0083] Comparative Example 3

[0084] Same as Example 1, except that the steam blanching temperature is set to 50°C.

[0085] The results showed that: (1) Due to the lower blanching temperature, the blanching was insufficient, resulting in unsatisfactory effects and affecting later storage. The shelf life was only 6-7 months, and the loss rate of aroma and numbing flavor was 29%. (2) Since there is a correlation between blanching temperature and steam flow rate, lowering the temperature made the blanching system difficult to control, involving many parameters and making the system difficult to adjust. (3) In the later stages, most of the peppercorns turned black, and the flavor substances decreased, limiting consumer choices. In summary, the blanching effect was poor due to the different blanching effects at different temperatures.

[0086] Comparative Example 4

[0087] Same as Example 1, except that the steam flow rate is 0.8 t / h.

[0088] The results showed that: (1) Due to the high steam velocity, the temperature rises rapidly, which will ripen the pepper pericarp, causing it to soften and affecting its long-term storage. (2) The shelf life is only 4 to 5 months. In the later stage, the fruit turns black, the color and sensory appearance are poor, and the aroma and numbing taste are lost by 32%. The biggest problem of Comparative Example 4 is that it damages the oil cells and pericarp of the pepper, which seriously reduces its storage performance.

[0089] Comparative Example 5

[0090] Same as Example 1, except that the immersion cooling time is 180s.

[0091] The results showed that: (1) The pericarp of the Sichuan pepper was soft, with a high moisture content and a yellow color. Its shelf life was only 5 to 6 months, less than half that of Examples 1 and 2. (2) The loss of aroma and numbing substances increased by 10% to 15% compared with Examples 1 and 2, and the flavor deteriorated. (3) It was difficult to put into the market in the later stage, resulting in a large amount of waste, with a loss of more than 25 yuan per kilogram of fresh pepper.

[0092] Comparative Example 6

[0093] Same as Example 1, except that the dried and blanched peppercorns were stored in cold storage at -10°C and 0°C respectively.

[0094] The results showed that: (1) When stored at -10℃, the shelf life was only 8 to 9 months, which was 3 to 4 months shorter than that of Example 1 and Example 2. The pepper pericarp turned yellow rapidly, and the loss rate of aroma and numbing flavor was 17%. (2) When stored at 0℃, the shelf life was only 2 to 3 months, which was much shorter than that of Example 1 and Example 2 (12 months). The pepper pericarp turned yellow, lost its luster, and had a lower sensory evaluation grade. The loss rate of aroma and numbing flavor was 34%.

[0095] It is evident that storing peppercorns under these temperature conditions shortens their shelf life, making it difficult to keep them on the market for extended periods. This significantly reduces the product's competitiveness and also affects consumers' perception of the peppercorn product.

[0096] Comparative Example 7

[0097] Sichuan peppercorns should be sealed immediately after harvesting and stored in a household refrigerator. The specific method is as follows: after harvesting the Sichuan peppercorns, immediately remove the leaves, petioles, impurities, etc., and then store them in a household refrigerator for later use.

[0098] The results showed that: (1) Sichuan pepper began to turn black, yellow, and deteriorate after about 15 days, with no white spots on the fruit surface. (2) The aroma and numbing sensation decreased, with a loss rate of 25%, resulting in a loss of good edible value. (3) Due to poor sensory qualities and taste, it could not be sold in the market. This indicates that Sichuan pepper should be treated with a combination of blanching and low-temperature storage to improve its shelf life. When necessary, fresh pepper processing services can be provided to farmers with small Sichuan pepper yields to meet their practical needs for long-term storage of fresh pepper.

[0099] In summary, based on Examples 1 and Comparative Examples 3 and 4, maintaining appropriate steam flow rate, blanching temperature, and time are crucial measures to extend the shelf life of fresh peppers and preserve key flavor compounds. Excessive steam flow rate leads to rapid temperature rise, shorter blanching time, and a higher risk of overripe fruit, and makes accurate parameter control difficult. Furthermore, based on Examples 1 and Comparative Example 6, improper temperature control can cause the peppercorns to lose their color.

[0100] Comparative Example 8

[0101] Same as Example 1, except that: soaking cooling is replaced by air drying cooling, and the air drying cooling process is the same as the air drying process in Example 1.

[0102] The results showed that the shelf life of Sichuan peppercorns was only 5-6 months. In the later stages, the peppercorns lacked a lasting aroma, the numbing sensation lasted for a shorter period, and the aroma and numbing sensation were reduced by more than 50%.

[0103] Comparative Example 9

[0104] Same as Example 1, except that steaming is replaced with stir-frying. The stir-frying method is as follows: heat the processed fresh peppers in an iron pot over a fire, control the temperature at 100°C, and the time is 5 minutes.

[0105] The results showed that the peppercorn pericarp softened and ripened, making it difficult to store later, with a shelf life of only 1-2 months. During the roasting process, the peppercorns changed color, resulting in poor sensory quality and significant loss of flavor compounds, with aroma and numbing sensation reduced by more than 30%.

[0106] Comparative Example 10

[0107] Same as Example 1, except that steaming is replaced with radiation blanching. The radiation blanching method is as follows: the processed fresh peppers are subjected to infrared radiation in an infrared oven, with the temperature controlled at 100°C and the time at 3 minutes.

[0108] The results showed that the shelf life of Sichuan pepper was shortened to 6-7 months, and the aroma and numbing sensation of Sichuan pepper were reduced by about 10%. Although the loss of aroma and numbing sensation of Sichuan pepper during radiation blanching was not significantly different from that in the example, the presence of oil cells made the radiation blanching effect less than ideal, making it difficult to uniformly raise and lower the temperature, resulting in uneven blanching of the raw materials and seriously damaging the quality of the product.

[0109] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for preserving Sichuan pepper fruits, characterized in that, Includes the following steps: S1. After the peppercorns are harvested, the leaves, petioles and impurities are removed first, and then they are transported and temporarily stored under low temperature conditions. S2. Soak and wash the fresh peppers to remove any new impurities generated during the washing process; S3. Steam the soaked and cleaned peppercorns to kill the green color. S4. After blanching, quickly soak the peppercorns in water to cool them down, and then air dry the surface moisture of the fruits. S5. After the pepper fruits are air-dried, they should be sealed in packaging and stored and transported under low-temperature conditions. The harvesting, transportation, and temporary storage time in S1 shall not exceed 7 hours; the soaking and washing time shall be 2-3 minutes; the steam flow rate during the steam blanching process shall be 0.45-0.55 t / h, the blanching temperature shall be 76℃-82℃, and the blanching time shall be 4-4.5 minutes; the soaking and cooling time shall be 70-80 seconds, and the drying time shall be controlled at 25-30 seconds; the storage temperature shall be -18℃ to -15℃, and the storage shall be kept sealed during the storage process.

2. The preservation method according to claim 1, characterized in that, The weight ratio of Sichuan pepper fruits to water during the soaking and cleaning process is 1:45~55.