Processing method of IQF quick-frozen preserved pepper

Abstract

The application discloses an IQF quick-frozen fresh-keeping Chinese prickly ash processing method, comprising the following steps: (1) selecting fresh red Chinese prickly ash particles with good color and luster, no rot and no mildew, and precooling the fresh red Chinese prickly ash particles in a freezer at 0-10 DEG C for 12 hours; (2) vacuumizing the precooled Chinese prickly ash in an aluminum-plastic composite bag (Al / PET / PE) or a PA / PE bag or a PET / PE bag; (3) placing the packaged Chinese prickly ash in a single layer on a carrier rack and feeding the Chinese prickly ash into a quick freezer, and adopting a liquid nitrogen cabinet type quick freezer to carry out single body quick freezing, wherein the quick freezing temperature is-80 DEG C to-120 DEG C, the quick freezing time is 10-25 min, and the holding time is 2-5 min; and (4) storing the quick-frozen Chinese prickly ash in a freezer at-10 DEG C to-20 DEG C. The application processes fresh-keeping Chinese prickly ash with dispersed particles and no quality loss, can better keep the fresh red color and flavor quality of fresh Chinese prickly ash, prolongs the shelf life of the fresh-keeping Chinese prickly ash product, and effectively solves the problems of browning, volatile oil and aroma component loss of fresh red Chinese prickly ash during storage.

Description

Technical Field

[0001] This invention belongs to the field of agricultural product processing technology, specifically relating to a processing method for IQF quick-frozen preserved fresh peppercorns. Background Technology

[0002] Sichuan pepper (Zanthoxylum bungeanum) is a variety of plants in the genus Zanthoxylum of the Rutaceae family that are both medicinal and edible, and is hailed as one of the "Eight Great Flavors." As an important economic crop, Sichuan pepper is widely cultivated in my country, with the largest planting area and yield in the world. It is extensively grown in southwestern China, especially in Sichuan Province, where it is a significant economic crop. Two main species are represented by Hanyuan Sichuan pepper (Zanthoxylum bungeanum Maxim.), with its bright red pericarp, and Zhuye Sichuan pepper (Zanthoxylum armatum DC.), with its emerald green fruit, commonly known as "green Sichuan pepper" or "vine pepper." Sichuan pepper is rich in nutrients such as protein, minerals, amino acids, and vitamins, and possesses various effects including antioxidant properties, inhibition of platelet aggregation, insecticidal and antibacterial properties, and anti-inflammatory and analgesic effects, making it highly valuable for consumption.

[0003] Fresh Sichuan peppercorns, due to their high moisture content, often face problems such as loss of volatile oils and aroma components, moisture absorption, mold, and browning during storage after harvesting. This results in a short shelf life and a concentrated market supply, which is mainly alleviated through processing. Preserving fresh Sichuan peppercorns is one type of processed product. Currently, the main processing method involves high-temperature steam sterilization to inactivate various enzymes that cause browning during storage. Further freezing is then used to preserve the peppercorns and delay browning. This method is currently widely used for green Sichuan peppercorns, effectively solving the problem of color stability. Chinese Patent 202011190266.9 discloses a method for preserving green Sichuan peppercorns. After harvesting, the green peppercorns are placed in a sealed environment, and 1-methylcyclopropene is introduced. After 4-6 hours of sealing, 1g of thyme oil is added, and the mixture is sealed for another 3-4 hours before steam inactivation of enzymes. After the green Sichuan peppercorns are steamed to deactivate their enzymes, they are placed in a circulating liquid nitrogen freezing system and flash-frozen to -18°C in 2-3 minutes. They are then vacuum-packed at -12°C ± 2°C, with a ClO2 slow-release agent (0.024%-0.036% of the peppercorns' mass) placed inside the bag. The package is then stored in a cold storage to complete the preservation process. Chinese Patent 201510783130.1 discloses a method for preserving green Sichuan peppercorns. The peppercorns are immersed in a 1:1 mixture of 0.2% citric acid and 0.3% vitamin C for 45-60 minutes, then blanched at 90-95°C for 1-2 minutes, quickly rinsed and cooled with running water, drained, vacuum-sealed, and stored at a low temperature in the dark.

[0004] Processing fresh Sichuan peppercorns using the method described in patent 201510783130.1 destroys their aroma components, resulting in significant differences in sensory evaluation before and after blanching. Furthermore, the high-temperature steam blanching process introduces considerable moisture into the sample, leading to severe loss of aroma components and causing the product to clump together after freezing, requiring thawing during use. Improper thawing methods can also alter product quality. Moreover, the aforementioned invention primarily targets chlorophyll color preservation in green Sichuan peppercorns; the structure and types of the red pigments that give Sichuan peppercorns their bright red color (such as Hanyuan peppercorns) are less well-documented, and color control technology for them urgently needs development. Therefore, researching how to ensure the color and flavor stability of fresh Sichuan peppercorns is of great significance.

[0005] Red Sichuan peppercorns and green Sichuan peppercorns have different pigment components, making it impossible to use the same preservation methods. Red Sichuan peppercorns are more difficult to preserve. The most obvious example is that there are almost no fresh red Sichuan peppercorn products on the market, while fresh green Sichuan peppercorns have long been available for sale. The main difficulties in preserving red Sichuan peppercorns are twofold: (1) Researchers do not know much about the red pigment (anthocyanins), so their stability is unclear; the chlorophyll in green Sichuan peppercorns is relatively well understood. (2) Red Sichuan peppercorns have more abundant oil glands than green Sichuan peppercorns (green Sichuan peppercorns also turn red in the later stages of maturity!). Therefore, when using the high-temperature blanching and color protection process commonly used in the preservation of green Sichuan peppercorns, the oil glands of red Sichuan peppercorns are severely damaged, and the loss of aroma is much higher than that of green Sichuan peppercorns. Furthermore, the study in the literature "Research on the variation law of pigment components in Dendrobium officinale flowers under different storage conditions" shows that under the condition of storage at 4℃ in the dark, after 5 months of storage, the total chlorophyll content in Dendrobium officinale flowers decreased by 17.4%, while the total anthocyanin content decreased by 51.4%, which also shows that the main pigment anthocyanins in Sichuan pepper are more difficult to preserve.

[0006] Regarding the preservation of Sichuan peppercorns, the existing patent CN111264746A discloses a method for freezing and preserving Sichuan peppercorns. The steps are: picking → pre-cooling → disinfection → blanching → coating → draining → screening → packaging → transportation → quick freezing → storage. First, pick deep red Sichuan peppercorns and pre-cool them in a mixture of ice and water at 0-5 degrees Celsius while simultaneously disinfecting them with ozone. Then, blanch them in a mixed solution of tea polyphenols, natural vitamin E, sorbitol, citric acid, and vitamin C. During blanching, chitosan and glycerin are added for coating. Then, remove the peppercorns, drain the water, and screen and grade them. Vacuum pack them in foil bags and transport them by refrigerated truck to a freezer at a temperature of -40 to -20 degrees Celsius for quick freezing for 1 to 3 days. Finally, store them in a cold storage at a temperature of -5 to 0 degrees Celsius. However, this patent not only has the aforementioned problems related to blanching, but it also uses ozone for disinfection. Ozone is a strong oxidizing gas, and studies have shown that the strong oxidizing properties of ozone can have a serious impact on the flavor of Sichuan peppercorns, reducing their numbing sensation. In addition, studies have also shown that vitamin C can destroy anthocyanins, leading to a decrease in their content and a worsening of the color of the peppercorns.

[0007] The literature "Research on Microenvironmental Controlled Atmosphere Preservation Technology of Sichuan Pepper" screened various combined preservation methods of pretreatment + preservative + controlled atmosphere. Under most conditions, the sensory score of Sichuan pepper will drop to 0 after about 20 days. Under the optimal preservation conditions, the quality of Sichuan pepper will also decrease significantly after 30 days. In addition, if the oxygen concentration in the controlled atmosphere is too low, the fruit is prone to off-flavors or rot due to anaerobic respiration. Moreover, the investment in controlled atmosphere storage is high, the cost is high, and the maintenance cost is high, so its effect on extending the shelf life of Sichuan pepper is limited.

[0008] This invention provides the first preservation technology for Sichuan peppercorns, enabling the processing of fresh peppercorns into dispersed particles with no loss of quality. Technically, it overcomes the shortcomings of current common preservation methods, which damage the cell structure and cause significant flavor loss in Sichuan peppercorns, thus preserving the quality of the peppercorns to the greatest extent possible. Summary of the Invention

[0009] The purpose of this invention is to provide a method for preserving Sichuan pepper using IQF quick-freezing technology. This aims to solve problems such as browning, loss of volatile oils and aroma components in fresh red Sichuan pepper during storage, thereby improving the product quality of preserved Sichuan pepper and extending its shelf life.

[0010] The objective of this invention is achieved through the following technical solution: a processing method for IQF quick-frozen preserved fresh Sichuan peppercorns, comprising the following steps:

[0011] (1) Select fresh red peppercorns with good color, no rot, and no mold, and pre-cool them in a freezer at 0-10℃ for 6-12 hours.

[0012] (2) Weigh the pre-cooled peppercorns at room temperature, pack them into a packaging bag, and vacuum-seal the bag.

[0013] (3) After packaging, the peppercorns are laid flat in a single layer on the rack and sent into the quick-freezing machine. The liquid nitrogen cabinet quick-freezing machine is used for individual quick-freezing. The quick-freezing temperature is -80 to -120℃, the quick-freezing time is 10 to 25 minutes, and the heat preservation time is 2 to 5 minutes.

[0014] (4) Store the quick-frozen Sichuan peppercorns in a freezer at -10 to -20°C.

[0015] Furthermore, the packaging bag is made of aluminum-plastic composite (Al / PET / PE), PA / PE, or PET / PE material, which can meet the requirements for normal use under quick-freezing temperature conditions.

[0016] Furthermore, in step (3), the thickness of the peppercorns stacked on the rack is ≤5cm.

[0017] The beneficial effects of this invention are as follows: Compared with existing technologies, this invention produces preserved Sichuan peppercorns with dispersed particles and excellent quality. Data from six months of testing by the research team shows that, under the optimized process, the various quality indicators of the red Sichuan peppercorns did not significantly decrease. In contrast, similar fresh Sichuan peppercorn preservation technologies typically exhibit significant browning within 1-3 days at room temperature, and lose commercial value within about one month under low-temperature or frozen storage conditions. The above experimental data demonstrates that this invention can effectively maintain the color and flavor quality of Sichuan peppercorns during storage periods of more than six months, extending the shelf life of preserved Sichuan peppercorn products and effectively solving the problems of browning, loss of volatile oils and aroma components in fresh red Sichuan peppercorns during storage. Attached Figure Description

[0018] Figure 1 This is a comparison diagram of the preservation effects of Sichuan peppercorns in Example 1 and Comparative Example 5 of the present invention;

[0019] Figure 2 A comparison chart showing the preservation effect of Sichuan peppercorns frozen for different times;

[0020] Figure 3 A comparison chart showing the preservation effect of Sichuan peppercorns with different quick-freezing layers. Detailed Implementation

[0021] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0022] Example 1

[0023] The test material was freshly harvested Hanyuan red peppercorns. Fresh red peppercorns with good color, no rot, and no mold were selected and pre-cooled in a 10℃ freezer for 12 hours. After pre-cooling, the peppercorns were weighed at room temperature and packaged into aluminum-plastic composite bags (Al / PET / PE) and vacuum-sealed. The packaged peppercorns were then fed into a quick-freezing machine in a single layer and quick-frozen individually using a liquid nitrogen cabinet-type quick-freezing machine. The quick-freezing temperature was -115℃, the quick-freezing time was 25 minutes, and a 2-minute holding time was applied to ensure the geometric center temperature of the peppercorns rapidly passed through -40℃ without sticking together. The quick-frozen peppercorns were then stored in a -18℃ freezer.

[0024] Example 2

[0025] The test material was freshly harvested Hanyuan red peppercorns. Fresh red peppercorns with good color, no rot, and no mold were selected and pre-cooled in a 10℃ freezer for 12 hours. After pre-cooling, the peppercorns were weighed at room temperature and packaged into PA / PE composite bags, which were then vacuum-sealed. The packaged peppercorns were laid flat in a single layer on a rack and placed into a quick-freezing machine using a liquid nitrogen cabinet-type quick-freezing unit. The quick-freezing temperature was -100℃, the quick-freezing time was 15 minutes, and a 5-minute holding time was applied to ensure the geometric center temperature of the peppercorns rapidly passed through -40℃ without sticking together. The quick-frozen peppercorns were then stored in a -18℃ freezer.

[0026] Comparative Example 1

[0027] The difference between Comparative Example 1 and Example 1 is that no pre-cooling step was performed.

[0028] Experimental results showed that when the oil glands of Sichuan pepper pericarp are ruptured, the quality of the pepper is easily deteriorated. This invention directly pre-cools fresh Sichuan pepper granules from the field, which can effectively reduce various biological activities of the Sichuan pepper and ensure its quality.

[0029] Comparative Example 2

[0030] The difference between Comparative Example 2 and Example 1 is that the order of the bagging and vacuuming steps and the quick-freezing steps has been reversed.

[0031] The experimental results showed that, since the harvested red peppercorns generally have some peppercorn branches attached (the peppercorn industry usually leaves some branches when harvesting, which can provide some nutrients for logistics transportation and the consumption of moisture and nutrients during short-term storage), the red peppercorns will freeze together with the branches after quick-freezing. In addition, the oil glands on the surface of the frozen peppercorns are more brittle and are easily broken during the packaging process.

[0032] Comparative Example 3

[0033] The difference between Comparative Example 3 and Example 1 is that no quick-freezing step was performed; the samples were directly sent to a freezer for storage.

[0034] The experiment revealed that when the water in Sichuan peppercorns passes through the ice crystal zone, it takes a long time and forms large ice crystals, which damage the cell walls.

[0035] Comparative Example 4

[0036] The difference between Comparative Example 4 and Example 1 is that the quick-freezing temperature is -196°C.

[0037] The experiment found that no commercially available packaging bag could withstand such low temperatures; the frozen bags became too brittle, which was not conducive to packaging.

[0038] Comparative Example 5

[0039] The difference between Comparative Example 5 and Example 1 is that the quick-freezing temperature is -60°C.

[0040] Experimental Example 1

[0041] The properties of Sichuan peppercorns from Examples 1 and 5, stored for 6 months, were determined (Note: Comparative Examples 1-4 do not have industrial potential and therefore were not tested). Before testing, the samples were thawed at 4°C for 1 hour. After complete thawing, the following indicators were measured using the following experimental methods:

[0042] Color: The appearance color of Sichuan peppercorns was measured using a handheld colorimeter. The specific operating steps are as follows: Sichuan peppercorns were spread flat in a petri dish, and the samples were measured using a handheld colorimeter in a room with normal temperature and sunlight. Five different detection points were selected for each sample, and the L*, a*, b*, and ΔE values ​​were recorded and the average value was calculated.

[0043] Numbing substances: Determined by ultraviolet spectrophotometry according to GH / T 1290—2020. Accurately weigh 5.0 g (accurate to 0.0001 g) of crushed Sichuan peppercorns, add 50.0 mL of pure methanol, extract in an ultrasonic bath for 30 min, filter, and transfer the filtrate to a 50.0 mL brown volumetric flask and dilute to volume. Pipette 0.02 mL of the diluted sample solution into a 10 mL volumetric flask and dilute to volume. Filter through a 0.22 μm filter membrane and determine by ultraviolet spectrophotometry.

[0044] Volatile oil content: Volatile oil was extracted according to GB / T17527-2009. Weigh 50.0g (accurate to 0.01g) of Sichuan pepper powder and place it in a 1000mL round-bottom flask. Add 3-4 glass beads, connect the distillation extraction apparatus, and inject 500.0mL of ultrapure water into the receiving tube. Adjust the power of the electric heating mantle and control the volatile oil to maintain a reflux rate of 2 drops per second for 4 hours. After distillation, cool to room temperature, read the volume of Sichuan pepper volatile oil using a volatile oil analyzer, and calculate the volatile oil content using the formula.

[0045] The experimental results are as follows:

[0046] Table 1. Data on various indicators of Sichuan peppercorns stored for different days in Example 1 and Comparative Example 5.

[0047]

[0048] The experimental results show that Comparative Example 5 darkened and turned black during storage, while Example 1 maintained a brighter color during storage, indicating better preservation than Comparative Example 5. (See Table 1 and...) Figure 1 As shown, it can be seen that after 180 days of storage, the L* value of Comparative Example 5 decreased by 46.96%, the a* value decreased by 61.72%, and the b* value decreased from 3.32 to -2.17. In contrast, after 180 days of storage, the L* value of Example 1 decreased by 18.90%, the a* value decreased by 14.35%, and the b* value decreased from 3.32 to -0.61. Compared with Example 1, after 180 days of storage, Comparative Example 5 showed a more significant decrease in L* (representing bright color), a* (representing red-green color), and b* (representing yellow-green color). The peppercorns in Comparative Example 5 showed a deterioration in color and obvious browning. Meanwhile, in Comparative Example 5, after 180 days of storage, the content of numbing and flavorful substances decreased from 32.52 mg / g to 24.21 mg / g (a decrease of 25.55%), and the volatile oil content decreased from 3.22 / 100g to 2.62 / 100g (a decrease of 18.63%). In Example 1, after 180 days of storage, the content of numbing and flavorful substances decreased from 32.52 mg / g to 8.28 mg / g (a decrease of 13.04%), and the volatile oil content decreased from 3.22 / 100g to 3.12 / 100g (a decrease of 3.11%). Compared with Comparative Example 5, Example 1 retained the numbing and flavorful substances and volatile oil content better, with less loss. The preserved fresh Sichuan peppercorns in Example 1 maintained their color well, without obvious browning, and showed no significant loss in numbing and flavorful substances, volatile oil content, and aroma components, thus preserving the color and flavor quality of the Sichuan peppercorns well.

[0049] Experimental Example 2

[0050] I. Screening Experiment for Optimal Quick-Freezing Time

[0051] The test material was freshly harvested Hanyuan red peppercorns. Fresh red peppercorns with good color, no rot, and no mold were selected and pre-cooled in a 10℃ freezer for 10 hours. After pre-cooling, the peppercorns were weighed at room temperature and packaged into aluminum-plastic composite bags (Al / PET / PE) and vacuum-sealed. The packaged peppercorns were then fed into a quick-freezing machine in a single layer and quick-frozen individually using a liquid nitrogen cabinet-type quick-freezing machine. The quick-freezing temperature was -120℃, and the quick-freezing times were 15 min, 20 min, 25 min, 30 min, and 35 min, respectively. A 2-minute holding period was applied to ensure the geometric center temperature of the peppercorns quickly passed through -40℃ without sticking together. The quick-frozen peppercorns were then stored in a -18℃ freezer.

[0052] The properties of Sichuan peppercorns with different quick-freezing times were determined after 3 months. Before the test, the samples were thawed at 4℃ for 1 hour. After complete thawing, the color, numbing flavor substances, and volatile oil content were measured. The experimental results are shown in Tables 2-6 below. Figure 2 As shown.

[0053] Table 2. Data on various indicators for storage for different days after quick-freezing time of 15 minutes.

[0054]

[0055] Table 3. Data on various indicators for storage for different days after quick-freezing time of 20 min.

[0056]

[0057] Table 4. Data on various indicators for storage for different days after quick-freezing time of 25 min.

[0058]

[0059]

[0060] Table 5. Data on various indicators for storage for different days after quick-freezing time of 30 min.

[0061]

[0062] Table 6. Data on various indicators for storage for different days after quick-freezing time of 35 min.

[0063]

[0064] After 90 days of storage, the L* value of samples quick-frozen for 15 min decreased by 9.49%, the a* value decreased by 20.54%, and the b* value decreased from 3.32 to -0.56; the L* value of samples quick-frozen for 20 min decreased by 5.68%, the a* value decreased by 17.44%, and the b* value decreased from 3.32 to -0.59; the L* value of samples quick-frozen for 25 min decreased by 6.88%, the a* value decreased by 18.01%, and the b* value decreased from 3.32 to -0.56; the L* value of samples quick-frozen for 30 min decreased by 7.55%, the a* value decreased by 29.08%, and the b* value decreased from 3.32 to -0.52; and the L* value of samples quick-frozen for 35 min decreased by 7.68%, the a* value decreased by 34.90%, and the b* value decreased from 3.32 to -0.69. This shows that after quick-freezing for more than 25 minutes, the L*, a*, and b* values ​​of Sichuan peppercorns decreased significantly, indicating that the color of Sichuan peppercorns was poorly preserved after 25 minutes and obvious browning occurred during storage.

[0065] After 90 days of storage, the numbing and aromatic compounds content of samples quick-frozen for 15 minutes decreased by 12.36%, and the volatile oil content decreased by 6.83%; samples quick-frozen for 20 minutes decreased by 10.24%, and the volatile oil content decreased by 5.59%; samples quick-frozen for 25 minutes decreased by 11.13%, and the volatile oil content decreased by 4.35%; samples quick-frozen for 30 minutes decreased by 10.95%, and the volatile oil content decreased by 8.07%; and samples quick-frozen for 35 minutes decreased by 11.22%, and the volatile oil content decreased by 8.07%. This indicates that after quick-freezing for more than 25 minutes, the decrease in the numbing and aromatic compounds of Sichuan pepper is not significant, but the decrease in the volatile oil content is significant, indicating a substantial loss of aroma components. Samples quick-frozen for more than 25 minutes experienced a greater decline in quality during storage.

[0066] II. Screening Experiment for the Optimal Number of Quick-Freezing Layers

[0067] The test material was freshly harvested Hanyuan red peppercorns. Fresh red peppercorns with good color, no rot, and no mold were selected and pre-cooled in an 8℃ freezer for 12 hours. After pre-cooling, the peppercorns were weighed at room temperature and packed into aluminum-plastic composite bags (Al / PET / PE) and vacuum-sealed. The packaged peppercorns were then placed in 1, 2, 3, 4, and 5 layers and fed into a quick-freezing machine using a liquid nitrogen cabinet-type quick-freezing unit. The quick-freezing temperature was -110℃, the quick-freezing time was 25 minutes, and a 2-minute holding time was applied to ensure the geometric center temperature of the peppercorns rapidly passed through -40℃ without sticking together. The quick-frozen peppercorns were then stored in a -18℃ freezer.

[0068] The properties of Sichuan peppercorns with different quick-freezing layers were determined after 3 months. Before testing, the samples were thawed at 4℃ for 1 hour. After complete thawing, the color, numbing flavor substances, and volatile oil content were measured. The experimental results are shown in Tables 7-11 and 7-12 below. Figure 3 As shown.

[0069] Table 7 shows the data for various indicators when the number of quick-freezing layers is 1 and the storage time is different for different days.

[0070]

[0071] Table 8 shows the data for various indicators when the number of quick-freezing layers is 2 and the storage time is different.

[0072]

[0073] Table 9 shows the data for various indicators when the number of quick-freezing layers is 3 and the storage time is different.

[0074]

[0075] Table 10 shows the data for various indicators when the freezer has 4 layers and the freezer is stored for different number of days.

[0076]

[0077] Table 11 shows the data for various indicators when the freezer has 5 layers and the freezer is stored for different number of days.

[0078]

[0079] After 90 days of storage, the L* value of the single-layer quick-frozen sample decreased by 6.01%, the a* value decreased by 14.82%, and the b* value decreased from 3.32 to -0.26; the L* value of the two-layer quick-frozen sample decreased by 8.82%, the a* value decreased by 24.39%, and the b* value decreased from 3.32 to -0.49; the L* value of the three-layer quick-frozen sample decreased by 8.02%, the a* value decreased by 29.55%, and the b* value decreased from 3.32 to -0.61; the L* value of the four-layer quick-frozen sample decreased by 8.62%, the a* value decreased by 36.12%, and the b* value decreased from 3.32 to -0.57; and the L* value of the five-layer quick-frozen sample decreased by 12.09%, the a* value decreased by 43.71%, and the b* value decreased from 3.32 to -0.45. This shows that as the number of quick-freezing layers increases, the color of Sichuan peppercorns deteriorates significantly, especially the a* value, which decreases significantly after the number of quick-freezing layers increases, and the Sichuan peppercorns show obvious browning.

[0080] After 90 days of storage, the content of numbing and aromatic compounds in single-layer quick-frozen samples decreased by 9.01%, and the volatile oil content decreased by 3.11%; in two-layer quick-frozen samples, the content decreased by 11.38%, and the volatile oil content decreased by 6.83%; in three-layer quick-frozen samples, the content decreased by 10.24%, and the volatile oil content decreased by 9.32%; in four-layer quick-frozen samples, the content decreased by 11.59%, and the volatile oil content decreased by 9.32%; and in five-layer quick-frozen samples, the content decreased by 14.18%, and the volatile oil content decreased by 12.42%. This shows that with the increase in the number of quick-freezing layers, the decrease in the content of numbing and aromatic compounds and the decrease in volatile oil content are significant, resulting in a substantial change in quality, a marked loss of numbing and aromatic components, and a deterioration in the quality of the Sichuan pepper.

[0081] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A processing method for IQF quick-frozen preserved fresh Sichuan peppercorns, characterized in that, Includes the following steps: (1) Select fresh red peppercorns with good color, no rot, and no mold, and pre-cool them in a freezer at 0~10℃ for 6~18 hours; (2) Weigh the pre-cooled peppercorns at room temperature, pack them into a packaging bag, and vacuum-seal the bag. (3) After packaging, the peppercorns are laid flat in a single layer on the rack and sent into the quick-freezing machine. The liquid nitrogen cabinet quick-freezing machine is used for individual quick-freezing. The quick-freezing temperature is -80~-120℃, the quick-freezing time is 10~25min, and the heat preservation time is 2~5min. (4) Store the quick-frozen Sichuan peppercorns in a freezer at -10~-20℃.

2. The processing method for IQF quick-frozen preserved fresh peppercorns according to claim 1, characterized in that, In step (2), the packaging bag is made of aluminum-plastic composite, PA / PE, or PET / PE material.

3. The processing method for IQF quick-frozen preserved fresh peppercorns according to claim 1, characterized in that, In step (3), the thickness of the peppercorns stacked on the rack is ≤5cm.

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