A rapid treatment method for improving the quality of da hongpao tangerine peel food

Abstract

The present application belongs to the field of food processing, and particularly relates to a rapid processing method for improving the quality of big red orange peel food products. The steps include: taking fresh big red orange peel, steaming for 2-6 hours, cooling, first rinsing with hot water, then rinsing with cold water, and alternately rinsing with hot water and cold water for 3-5 times, and drying. The two-step combined process of steaming and alternately rinsing with hot water and cold water can reduce the bitterness of big red orange peel without natural aging for several years, and can achieve the surprising effect of maximum retention of beneficial ingredients in only 1-2 days, which has practical popularization and application value.

Description

Technical Field

[0001] This invention relates to the field of food processing, and in particular to a rapid processing method for improving the edible quality of Da Hong Pao orange peel. Background Technology

[0002] Da Hong Pao tangerines ( Citrus reticulata 'Dahongpao', also known as red tangerine, Sichuan tangerine, or Fuzhou tangerine, is a long-cultivated loose-skinned tangerine variety, whose peel has outstanding nutritional and bioactive component value. Studies have confirmed that the total flavonoid content in Dahongpao tangerine peel is particularly high among different citrus varieties, with measurements showing a total flavonoid content as high as 122.5 mg / g, several times that of ordinary varieties. These flavonoids include hesperidin, polymethoxylated flavonoids (such as norihesperidin and tangeretin), and other bioactive components, possessing various health benefits such as antioxidant and anti-inflammatory properties. In addition, the tangerine peel is also rich in essential oils, pectin, dietary fiber, and limonene compounds. The peel of Dahongpao tangerine accounts for 20%-25% of the total fruit weight, making its resource quantity considerable. However, like many citrus peels, the peel of Da Hong Pao orange also contains bitter substances such as limonene, and it also has a certain pungent and bitter taste due to the presence of volatile oils and other components. This affects its fresh taste to some extent and makes its direct application in the food industry a challenge.

[0003] Therefore, there is an urgent need to develop a rapid, efficient, and chemical-free physical debittering method to significantly reduce the bitterness of orange peel in a short time while preserving its beneficial components and natural flavor to the maximum extent. This technological breakthrough will not only solve the key bottleneck restricting the food utilization of Da Hong Pao orange peel, but will also provide a feasible path for the high-value utilization of citrus processing by-products, which has important industrial application significance. Summary of the Invention

[0004] To achieve the above objectives, the present invention provides a rapid processing method for improving the edible quality of Da Hong Pao orange peel, comprising the following steps: Take fresh Da Hong Pao orange peel, steam it for 2-6 hours, cool it, rinse it with hot water first, then rinse it with cold water, repeat this process of rinsing with hot and cold water 3-5 times, and then dry it.

[0005] Furthermore, the fresh Da Hong Pao orange peel refers to the peel of Da Hong Pao tangerines that remains fresh after being washed with clean water and having impurities removed.

[0006] Furthermore, the temperature of the clean water is below 25°C.

[0007] Furthermore, during the steaming process, the orange peel is laid out in a single layer, with the thickness of the layer controlled to not exceed 5 cm, and steamed at 100°C under normal pressure saturated steam conditions.

[0008] Furthermore, the steaming time is 4-6 hours, during which the food is turned 1-3 times.

[0009] Furthermore, the steaming time is 6 hours.

[0010] Furthermore, the cooling is natural cooling to 30-40°C.

[0011] Furthermore, the hot water rinsing temperature is 90-100℃, and the rinsing time is 0.5-1.5 min; the cold water rinsing temperature is 4-25℃, and the rinsing time is 0.5-1.5 min.

[0012] Furthermore, the water is rinsed repeatedly with alternating hot and cold water five times.

[0013] Furthermore, the drying process involves drying at 60-70℃ for 1-2 hours, then drying at 40-50℃ for 8-14 hours, and finally drying at 30-40℃ for 1-2 hours.

[0014] This invention presents a rapid processing method for improving the edible quality of Da Hong Pao tangerine peel. Through a two-step process combining steaming and alternating hot and cold water rinsing, the bitterness score of Da Hong Pao tangerine peel can be reduced from 9.0 to below 1.0 in just 1-2 days, eliminating the need for years of natural aging. The debitterness rate exceeds 90%, and the hesperidin removal rate reaches 68.3%. Although the absolute contents of hesperidin and hesperidin + tangeretin (total PMF) decrease during rinsing, the PMF / total flavonoid ratio increases from 0.153 to 0.318 (+107.8%), significantly improving the relative proportion of polymethoxylated flavonoids in the total flavonoids, thus effectively optimizing the component ratio. This is a surprising effect that existing tangerine peel debitterness processes cannot achieve—reducing bitterness while maximizing the retention of beneficial components—and has practical application value.

[0015] This invention offers highly controllable processes. By discovering and utilizing the negative correlation between the ratio of noriheptacortin to tangeretin content and the number of alternating treatments, quantifiable process quality control indicators were established, enabling precise regulation of the debittering degree and ensuring product quality stability. The method of this invention is natural and safe, using only steam and water for physical treatment throughout the entire process, without adding any chemical reagents, thus avoiding chemical residue problems and guaranteeing the natural and safe properties of the product.

[0016] Obviously, based on the above description of the present invention, and according to common technical knowledge and conventional methods in the field, various other modifications, substitutions or alterations can be made without departing from the basic technical concept of the present invention.

[0017] The following detailed embodiments further illustrate the above-described content of the present invention. However, this should not be construed as limiting the scope of the present invention to the following examples. All technologies implemented based on the above-described content of the present invention fall within the scope of the present invention. Attached Figure Description

[0018] Figure 1 Samples of Da Hong Pao orange peel Figure 2 Chart showing the percentage of bitterness in the peel flavor of Da Hong Pao oranges; Figure 3 Flow velocity study results; Figure 4 Column temperature investigation results; Figure 5 Standard curve of hesperidin; Figure 6 Standard curve of tangeretin; Figure 7 Standard curve of hesperidin; Figure 8 Changes in total polymethoxyflavonoid (PMF) content and PMF / total flavonoid ratio in Da Hong Pao orange peel at different steaming times; Figure 9 The effect of rinsing times on the ratio of hesperidin / hesperidin in Da Hong Pao orange peel; Figure 10 Changes in the PMF / total flavonoid ratio in Da Hong Pao orange peel under different rinsing cycles; Figure 11 Comparison of four key process points: untreated, steamed for only 6 hours, rinsed only 5 times, and steamed for 6 hours and rinsed 5 times; Figure 12 Results of flow velocity determination using characteristic spectra; Figure 13 Results of column temperature determination based on characteristic spectra; Figure 14 Delayed investigation; Figure 15 Chromatographic peak identification; Figure 16 Overlay image of the characteristic features of Da Hong Pao orange peel; Figure 17 Relative peak area thermograms of Da Hong Pao orange peel processed with different techniques relative to the original sample; Figure 18 PCA plots of peak areas from various batches of Da Hong Pao orange peel samples. Detailed Implementation

[0019] This invention aims to solve the problems existing in the processing technology of Da Hong Pao citrus peel, such as long debittering cycle, poor effect, serious loss of effective ingredients, and possible chemical residues. Da Hong Pao citrus ( Citrus reticulata The peel of 'Dahongpao' citrus fruit is rich in various active ingredients, but its strong bitterness limits its direct application as a food ingredient. This invention provides a rapid, efficient, and entirely physical debittering method that not only significantly reduces bitterness but also optimizes and enriches the functional components in the peel, and establishes quantifiable process control standards. The core technical idea of ​​this invention lies in organically combining "heat treatment using steam" with "alternating hot water treatment and cold water treatment." The pretreatment modification of the former creates conditions for the efficient debittering of the latter, thereby obtaining high-quality Dahongpao citrus peel products in a short time.

[0020] In the description of this invention, some terms have specific meanings. Among them, "Da Hong Pao citrus peel" specifically refers to the citrus variety Da Hong Pao (… Citrus reticulata The peel of 'Dahongpao' fruit. "Heat treatment using steam" refers to the process of heating the peel with saturated steam at atmospheric pressure. "Alternating hot and cold water treatment" refers to immersing the peel in hot and cold water sequentially, repeating this cycle. "Polymethoxyflavones" refers to a specific class of flavonoid compounds, mainly including hesperidin and tangeretin in this invention. "Total flavonoids" refers to the total number of flavonoid compounds in the sample, mainly including hesperidin, hesperidin, and tangeretin in this invention. "Ratio of hesperidin to tangeretin content" refers to the ratio of the hesperidin content determined by high-performance liquid chromatography to the tangeretin content.

[0021] The reagents, raw materials, and equipment used in the following embodiments of the present invention are all known products and were obtained by purchasing commercially available products.

[0022] Example 1: Debittering of Da Hong Pao Orange Peel 1) Take fresh Da Hong Pao orange peel, wash it with water below 25℃ to remove impurities, drain it and spread it in a single layer in a stainless steel steamer with a thickness of ≤5 cm. Steam it with 100℃ normal pressure saturated steam for 6 hours, turning it 3 times during the process. After steaming, spread it in a clean container and let it cool naturally to 30-40℃ with a thickness of ≤3 cm. 2) Take the cooled orange peel obtained in step 1), rinse it with 100℃ hot water for 1 minute at a ratio of 1:5 (mass ratio), drain it, and then rinse it with 25℃ cold water at the same ratio for 1 minute. Repeat this process of alternating hot and cold water 5 times. Finally, place it in a hot air circulating oven to dry. The drying process is as follows: dry at 60℃ for 2 hours, then at 40℃ for 14 hours, and finally at 30℃ for 2 hours.

[0023] Example 2: Debittering of Da Hong Pao Orange Peel 1) Take fresh Da Hong Pao orange peel, wash it with water below 25℃ to remove impurities, drain it and spread it in a single layer in a stainless steel steamer with a thickness of ≤5 cm. Steam it with 100℃ normal pressure saturated steam for 2 hours, turning it 3 times during the process. After steaming, spread it in a clean container and let it cool naturally to 30-40℃ with a thickness of ≤3 cm. 2) Take the cooled orange peel obtained in step 1), rinse it with 100℃ hot water for 1 minute at a ratio of material to liquid of 1:5 (mass ratio), then rinse it with 15℃ cold water at the same material to liquid ratio for 1 minute. Repeat this process of alternating hot and cold water 3 times. Finally, place it in a hot air circulating oven to dry. The drying process is as follows: dry at 70℃ for 1 hour, then at 50℃ for 8 hours, and finally at 40℃ for 1 hour.

[0024] Example 3: Debittering of Da Hong Pao Orange Peel 1) Take fresh Da Hong Pao orange peel, wash it with water below 25℃ to remove impurities, drain it and spread it in a single layer in a stainless steel steamer with a thickness of ≤5 cm. Steam it with 100℃ normal pressure saturated steam for 4 hours, turning it 3 times during the process. After steaming, spread it in a clean container and let it cool naturally to 30-40℃ with a thickness of ≤3 cm. 2) Take the cooled orange peel obtained in step 1), rinse it with 100℃ hot water for 1 minute at a material-to-liquid ratio of 1:5 (mass ratio), then rinse it with 4℃ cold water at the same material-to-liquid ratio for 1 minute. Repeat this alternating hot and cold water operation 4 times. Finally, place it in a hot air circulating oven to dry. The drying process is as follows: dry at 70℃ for 1 hour, then at 50℃ for 8 hours, and finally at 40℃ for 1 hour.

[0025] The following experimental examples further illustrate the beneficial effects of the present invention: Experimental Example 1: Research on the Process of Improving the Quality of Da Hong Pao Orange Peel 1. Preparation of Da Hong Pao Orange Peel 1.1 Raw material pretreatment 1.1.1 Raw material selection and cleaning Select Da Hong Pao tangerines with orange-yellow peels and plump oil pores. Peel the fruit, ensuring the peel is free of mold, insect infestation, and mechanical damage. Rinse the peel in running water for 5-15 minutes, keeping the water temperature below 25℃, to remove surface residue and microorganisms while preventing premature dissolution of active ingredients due to high temperatures. Drain the surface water after rinsing.

[0026] 1.1.2 Cutting The peel can be cut into strips or slices as needed. In this study, whole peels were used directly without cutting.

[0027] 1.2 Steaming process The washed fruit peels were laid in a single layer in a stainless steel steamer, with a thickness of ≤5 cm to ensure even steam penetration. Saturated steam at atmospheric pressure was used for steaming at 100℃. Steaming time: 1 hour per batch. Depending on the desired degree of aging, steaming can be repeated 1-6 times. In this study, samples were prepared for steaming for 2 hours, 4 hours, and 6 hours (i.e., 2, 4, and 6 consecutive steamings, 1 hour each). The fruit peels were turned 1-3 times during steaming to ensure even heating. The steaming endpoint was marked by significant softening of the peel, a color change from bright yellow to yellowish-brown, and a change in aroma from grassy to aged.

[0028] After steaming, immediately remove the fruit peel, spread it out in a clean container, and let it cool naturally to a thickness of ≤3 cm until it reaches 30-40℃.

[0029] 1.3 Rinse with alternating hot and cold water to remove bitterness The cooled fruit peels are repeatedly rinsed. Each round of rinsing includes: hot water rinsing: the fruit peels are put into 100℃ hot water and rinsed for 1 minute, with a material-to-liquid ratio of 1:5, then drained; cold water rinsing: the fruit peels are immediately put into 25℃ cold water and rinsed for 1 minute, with the same material-to-liquid ratio, then drained.

[0030] Repeat the hot-cold water alternating rinsing operation as described above, for a total of 3-5 rinsing times. In this study, samples were prepared after steaming for 6 hours and then boiling and rinsing 1, 2, 3, 4, and 5 times (i.e., after steaming, 1 to 5 complete hot-cold alternating rinsings were performed sequentially).

[0031] Meanwhile, as a comparison, samples were also prepared that were not steamed and only rinsed with alternating hot and cold water 1-5 times, as well as samples that were steamed for 2-6 hours and not rinsed.

[0032] 1.4 Drying The rinsed fruit peels are placed in a hot air circulating oven and dried in three stages: First stage: Temperature 60-70℃, time 1-2 hours, to quickly remove surface moisture.

[0033] Second stage: Temperature 40-50℃, time 8-14 hours, slowly remove internal moisture while retaining aroma components.

[0034] The third stage: temperature 30-40℃, time 1-2 hours, to balance moisture, enhance aroma and set shape.

[0035] Dry until the fruit peel is crisp and not easily broken.

[0036] 1.5 Finished Product Detailed information on the Da Hong Pao orange peel samples processed using the aforementioned steps is shown in Table 1. Some sample images are available in [link to table]. Figure 1 .

[0037] Table 1. Information on Da Hong Pao orange peel samples 2. Experimental Instruments and Reagents High-performance liquid chromatography (HPLC): Agilent series HPLC; Shimadzu series HPLC Electronic balances: ME204E / 02, XPE26 (Mettler-Toledo Instruments Ltd.); Ultrapure water system: Cellular type 1810A (Shanghai Moler Scientific Instruments Co., Ltd.); Ultrasonic cleaner: KQ600DB model (600W, 40KHz; Kunshan Ultrasonic Instrument Co., Ltd.); Chromatographic columns: ZORBAX SB-C18 4.6×250mm 5µm; InfinityLab Poroshell 120 SB-C18 2.1×100mm 2.7µm; Acetonitrile and methanol were of chromatographic grade, water was ultrapure water, and all other reagents were of analytical grade.

[0038] Hesperidin (China National Institutes for Food and Drug Control, batch number: 110721-202220, content calculated as 97.20%). Hesperidin (Sichuan Weikeqi Biotechnology Co., Ltd., batch number: wkq18020111, content calculated as 98.00%) Hesperidin (China National Institutes for Food and Drug Control, batch number: 112054-202102, content calculated as 99.70%). Viclin-2 (China National Institutes for Food and Drug Control, batch number: 112096-202201, for identification purposes); 3 Sensory evaluation 3.1 Sensory evaluation methods Ten healthy volunteers (5 males and 5 females, aged 22-35 years) without taste dysfunction were recruited. All evaluators fasted and refrained from smoking for 1 hour prior to the experiment, drinking only purified water. 1.0 g of each sample powder was added to 100 mL of boiling water and steeped for 5 minutes. The solution was filtered, collected, and cooled to room temperature. Each sample was assigned a three-digit random code and provided to the evaluators in random order. A 10-point linear scaling method (0 = no bitterness, 10 = extremely bitter) was used for scoring. Each evaluator held approximately 10 mL of the sample solution in their mouth for 10 seconds, then spat it out, rinsed their mouth with purified water, and evaluated the next sample after a 1-minute interval. Each sample was evaluated once, and the average value was taken. All data are expressed as x̄±SD.

[0039] 3.2 Sensory evaluation results The sensory scores for bitterness of Da Hong Pao orange peel processed using different techniques are shown in Table 2.

[0040] Table 2. Sensory scores of bitterness of Da Hong Pao orange peel processed by different methods (out of 10, n=10, x̄±SD) As shown in Table 2, the original sample (R-0) had a bitterness score of 9.0±0.67, which is in the range of extremely bitterness. Only the scores of the steaming treatments (S-2, S-4, S-6) decreased to 5.0-5.5, which is still moderately bitter. Only the scores of the water washing treatments (W-1~W-5) fluctuated between 4.1-5.9, with a limited decrease. However, the scores of the water washing after steaming (SW-6-1~SW-6-5) decreased significantly with the increase of the number of water washings. Among them, the score of SW-6-3 (steamed for 6 hours + washed 3 times) decreased to 0.9±0.74, and the scores of SW-6-4 and SW-6-5 decreased to 0.4±0.52 and 0.6±0.70, respectively.

[0041] To further visually demonstrate the relative contribution of each sample to the overall bitterness, a pie chart was created by summarizing the original scores from the 10 evaluators, as shown below. Figure 2 As shown, compared with the original sample (16%), the bitterness percentage of the orange peel samples (SW-6-3, SW-6-4, SW-6-5) treated with steaming for 6 hours and washing with water 3-5 times was only 1%, which is less than one-fifth of the original sample. This indicates that the treatment method of steaming for 6 hours and washing with water 3-5 times has a significant effect on improving the bitterness of Da Hong Pao orange peel.

[0042] 4. Determination of the content of multiple components 4.1 Determination of the determination method 4.1.1 Chromatographic conditions and system suitability test The column was filled with octadecylsilane-bonded silica gel (250 mm column length, 4.6 mm inner diameter, 5 μm particle size); acetonitrile was used as mobile phase A and water as mobile phase B, and gradient elution was performed according to the specifications in the table below; the detection wavelength for hesperidin was 283 nm, and the detection wavelengths for norepinephrine and citric acid were 330 nm. The theoretical plate number, calculated based on the hesperidin peak and the norepinephrine peak, should be no less than 2000.

[0043] 4.1.2 Preparation of reference solution Take appropriate amounts of hesperidin reference standard, norepinephrine reference standard, and citrus terpenoid reference standard, accurately weigh them, and add methanol to prepare a mixed solution containing 0.2 mg of hesperidin, 25 μg of norepinephrine, and 15 μg of citrus terpenoid per 1 mL.

[0044] 4.1.3 Preparation of the test solution Take about 0.2g of coarse powder of Da Hong Pao orange peel (passed through a No. 2 sieve), weigh it accurately, place it in a stoppered conical flask, add 25mL of methanol accurately, stopper tightly, weigh it, sonicate (power 300W, frequency 40kHz) for 45 minutes, cool it, weigh it again, make up the weight loss with methanol, shake well, filter it, and take the filtrate to obtain the product.

[0045] 4.1.4 Determination Method Accurately pipette 5 μl each of the reference solution and the test solution into the liquid chromatograph and determine the result.

[0046] 4.2 Methodological Investigation of Multi-Component Content Determination 4.2.1 Chromatographic conditions and system suitability test 4.2.1.1 Flow velocity investigation The flow rates of 0.8 mL / min, 1.0 mL / min, and 1.2 mL / min were investigated under the above experimental conditions. See [link / reference]. Figure 3 The results showed that the chromatogram peak shape and separation were better when the flow rate was 1.0 mL / min, and the proposed flow rate was 1.0 mL / min.

[0047] 4.2.1.2 Column Temperature Investigation Based on the above-specified experimental conditions, the results were investigated at column temperatures of 25℃, 30℃, and 35℃. (See...) Figure 4 The results showed that a column temperature of 30℃ resulted in better peak shape and separation. A column temperature of 30℃ was tentatively set.

[0048] The method for determining the content of Da Hong Pao orange peel is as follows: Octadecylsilane-bonded silica gel is used as the packing material (column length 250 mm, inner diameter 4.6 mm, particle size 5 μm); acetonitrile is used as mobile phase A, and water is used as mobile phase B, with gradient elution performed according to the specifications in the table below; the flow rate is 1.0 ml per minute; the column temperature is 30℃; the detection wavelength for hesperidin is 283 nm, and the detection wavelengths for norepinephrine and citrulline are 330 nm. The theoretical plate number, calculated based on the hesperidin peak and the norepinephrine peak, should not be less than 2000.

[0049] The assay involves precisely pipetting 5 μl of both the reference solution and the test solution into a liquid chromatograph and measuring the results.

[0050] 4.2 Methodological Examination 4.2.1 Precision Examination The mixed reference solution was injected six times consecutively, the peak area was recorded, and the RSD value was calculated. The results are shown in Table 3.

[0051] Table 3. Precision test results As can be seen from the above, the peak area RSD values ​​of each reference standard in the precision test were all less than 2.0%, indicating that the instrument precision was good.

[0052] 4.2.2 Linear Relationship Accurately pipette the mother liquor of the mixed reference standard to prepare reference standard solutions of different concentrations. Inject 5 μl of each solution into the liquid chromatograph and obtain the peak area. Plot a response curve with reference standard concentration (X, µg / mL) on the x-axis and peak area (Y) on the y-axis. The results are shown in Table 4 and [Table data would be inserted here]. Figure 5 , 6 7.

[0053] Table 4. Results of Standard Curve Analysis The results showed that the linear regression equation for hesperidin was y = 9.3489x - 34.6164, with a correlation coefficient R² = 0.9992, indicating a good linear relationship between hesperidin concentration and peak area within the concentration range of 39.59928–395.9928 μg / mL. The linear regression equation for nonocitretin was y = 19.0798x - 15.2462, with a correlation coefficient R² = 0.9990, indicating a good linear relationship between nonocitretin concentration and peak area within the concentration range of 8.526–85.26 μg / mL. The linear regression equation for citrinin was y = 21.1360x - 6.3458, with a correlation coefficient R² = 0.9990, indicating a good linear relationship between citrinin concentration and peak area within the concentration range of 3.057799–30.57799 μg / mL. 4.2.3 Repeatability Take 6 portions of the crude powder of this product (batch number: R-0), accurately weigh them, and have the same operator prepare the test solution according to the determined method. Accurately pipette 5 μl of each test solution and inject it into the liquid chromatograph. Calculate the content of hesperidin, nonotrimonin and citrus peel reference standards in the 6 samples. The results are shown in Table 5.

[0054] Table 5 Results of Repeatability Experiments The results showed that the RSD values ​​of hesperidin, noriheptacortin, and citrus reproducibility were less than 3%, indicating that the method had good reproducibility.

[0055] 4.2.4 Intermediate Precision Based on the above-established experimental conditions, different personnel conducted measurements at different times. A sample of Da Hong Pao orange peel (batch number: R-0) was accurately weighed, and a test solution was prepared according to the determined method for analysis. The calculated contents of hesperidin, nonotrimonin, and tangeretin reference standards are shown in Table 6.

[0056] Table 6 Results of intermediate precision testing The results showed that the RSD values ​​of hesperidin, noriheptacortin, and citrus terpenoid were less than 3%, indicating good intermediate precision of this method.

[0057] 4.2.5 Recovery rate Take six samples of known-content test sample (batch number: R-0), with hesperidin content of 2.242 mg / g, norepinephrine content of 0.533 mg / g, and citrus reticulatae content of 0.183 mg / g. Accurately weigh each sample and add a certain amount of mixed reference standard. Prepare the test sample solution according to the established method and determine the recovery rate. The results are shown in Table 7. The calculation formula is as follows: Table 7 Results of the recovery experiment The results showed that the average recovery rates of each indicator component were all between 95% and 105%. The method demonstrated good accuracy.

[0058] 4.2.6 Stability Test According to the experimental conditions proposed above, a test solution was prepared, and the peak area of ​​each index was measured at 0h, 2h, 6h, 8h, 12h and 24h respectively. The results are shown in Table 8.

[0059] Table 8. Stability test results The results showed that under the experimental conditions, the RSD% of each index component was below 3%, and the test solution had good stability within 24 hours.

[0060] 4.3 Validation of Sample Content Determination Multiple batches of Da Hong Pao orange peel samples were tested according to the proposed method, and the results are shown in Table 9.

[0061] Table 9. Results of content determination in multiple batches of Da Hong Pao orange peel samples. Note: Total PMF = hesperidin + tangeretin; Total flavonoids = hesperidin + hesperidin + tangeretin.

[0062] 4.4 Data Analysis of the Process for Removing Bitterness from Orange Peel in Da Hong Pao Tea 4.4.1 Effect of steaming time on total PMF and PMF / total flavonoids like Figure 8The results show that, compared with the original sample (R-0, total PMF = 0.758%, PMF / total flavonoids = 0.153), after steaming for 2 hours (S-2), the total PMF increased to 0.801% (+5.7%), and the PMF / total flavonoids ratio increased to 0.192 (+25.7%); after steaming for 4 hours (S-4), the total PMF was 0.774% (+2.2%), and the PMF / total flavonoids ratio increased to 0.203 (+33.0%); after steaming for 6 hours (S-6), the total PMF was 0.791% (+4.5%), and the PMF / total flavonoids ratio increased to 0.223 (+45.8%). The total PMF peaked after 2 hours of steaming and fluctuated slightly, but remained at a level higher than the original sample overall; the PMF / total flavonoids ratio showed an overall upward trend with increasing steaming time, reaching its highest value (0.223) at 6 hours of steaming.

[0063] The above indicates that steaming effectively promotes the release or conversion of polymethoxylated flavonoids such as hesperidin and citrinin, allowing the total PMF to reach a high level within 2 hours of steaming. Simultaneously, highly polar flavonoid glycosides such as hesperidin undergo partial degradation or conversion during steaming, leading to a decrease in total flavonoid content and thus a continuous increase in the PMF / total flavonoid ratio. These results suggest that steaming itself can, to some extent, achieve the enrichment effect of active ingredients during the natural aging process of orange peel. Considering both energy consumption and efficiency, steaming for 4-6 hours is feasible, with 6 hours yielding the best results.

[0064] 4.4.2 Effect of rinsing times on norepinephrine / hesperidin Depend on Figure 9 It can be seen that the ratio of norihesperidin / hesperidin generally decreased with the increase of rinsing times, but there were significant differences between the two groups. In the rinsing-only groups (W-1~W-5), the ratio decreased from 2.846 (W-1) to 2.728 (W-5), an overall decrease of 4.1%, but there were fluctuations during the process (W-2:2.672→W-3:2.748→W-4:2.788), indicating that the regulation of the norihesperidin / hesperidin ratio of untreated tangerine peel during rinsing was not stable enough. In contrast, the ratio of the rinsing groups after 6 hours of steaming (SW-6-1~SW-6-5) continuously decreased from 2.496 (SW-1) to 2.100 (SW-5), a decrease of 15.9%, and showed a monotonous downward trend (the ratio of 2.222 in SW-4 was only slightly higher than that in SW-3 (2.216), which can be regarded as experimental fluctuation). The above results indicate that steaming pretreatment significantly improves the stability and efficiency of rinsing in controlling the Sichuan / Citrus ratio.

[0065] To investigate the effect of the number of rinsing cycles on the ratio of nonocitretin to hesperidin in Da Hong Pao tangerine peel, Pearson correlation analysis was performed on the number of rinsing cycles (1–5 times) and the corresponding nonocitretin / hesperidin ratios for each rinsing cycle. The results are shown in Table 10.

[0066] Table 10. Pearson correlation analysis results between the number of rinsing cycles and the ratio of nonotrimonene / hesperidin under different treatment conditions. Table 10 shows that the ratio of katsuobushi to tangerine peel only fluctuated between 2.672 and 2.846 in the rinsing groups (W-1 to W-5) (W-5 was 2.728). Pearson correlation analysis showed no significant linear correlation between the number of washes and the katsuobushi to tangerine peel ratio (r = -0.286). p =0.641), indicating that the dissolution behavior of tangeretin and hesperidin in untreated orange peel during rinsing is inconsistent, and the ratio between the two cannot be effectively controlled by the number of rinsing cycles. In the rinsing group after steaming (SW-6-1~SW-6-5), the tangeretin / citrus peel ratio monotonically decreased from 2.496 (SW-1) to 2.100 (SW-5). Pearson correlation analysis showed that the two were significantly negatively correlated (r=-0.966, p =0.007), indicating that the steaming pretreatment made the dissolution behavior of norihesperidin and tangerine tend to be consistent, and a highly controllable linear response relationship was established between the number of rinsing and the nori / tangerine ratio.

[0067] The above results indicate that the Sichuan / orange ratio was not significantly correlated with the number of rinsing cycles in the rinsing group (r = -0.286). p =0.641), while the correlation was extremely significant in the rinsing group after steaming (r=-0.966). p =0.007). Steaming pretreatment is a key prerequisite for transforming the rinsing process from "uncontrollable" to "controllable". The degree of debittering can be inferred by measuring the ratio of norihesperidin to tangeretin, enabling rapid determination of the process endpoint.

[0068] 4.4.3 Effect of rinsing frequency on PMF / total flavonoids Depend on Figure 10 It can be seen that after steaming for 6 hours, the PMF / total flavonoid ratio generally showed an upward trend with the increase of rinsing times. During the period of rinsing 1 to 4 times, the ratio fluctuated between 0.274 and 0.289 with a small change range; during the 5th rinse, the ratio increased significantly from 0.274 to 0.318 (+16.1%).

[0069] The above-mentioned changes indicate that during the first four washes, the dissolution rates of hesperidin and PMF were similar, and the PMF / total flavonoid ratio remained relatively stable. The ratio increased significantly during the fifth wash, indicating that the dissolution rate of hesperidin was significantly higher than that of PMF at this point. This may be related to the cell wall damage caused by the first four washes—when the fifth wash was accumulated, the cell wall structure changed, leading to the release of a large amount of hesperidin, while PMF was relatively retained. This result corroborates the sharp decrease in hesperidin levels (1.831→1.328) during the fifth wash, jointly indicating that the fifth wash is a crucial point for achieving efficient debittering and relative enrichment of PMF.

[0070] 4.4.4 Comprehensive Comparison of Key Process Points Four representative samples—R-0 (original sample), S-6 (steamed for 6 hours only), W-5 (rinsed 5 times only), and SW-6-5 (steamed for 6 hours + rinsed 5 times)—were selected for comprehensive comparison. The results are as follows: Figure 11 As shown. Regarding hesperidin content, S-6 (2.755%) decreased by 34.3% compared to R-0 (4.192%), W-5 (2.416%) decreased by 42.4%, while SW-6-5 (1.328%) showed the largest decrease, decreasing by 68.3% compared to R-0, 51.8% compared to S-6, and 45.0% compared to W-5. Regarding nonocitric acid content, S-6 (0.561%) was basically the same as R-0 (0.563%), W-5 (0.568%) increased slightly, and SW-6-5 (0.419%) decreased. Regarding hesperidin content, S-6 (0.231%) and W-5 (0.208%) were both higher than R-0 (0.195%), while SW-6-5 (0.200%) was slightly higher than R-0. Regarding total PMF content, S-6 (0.791%) and W-5 (0.776%) were slightly higher than R-0 (0.758%), while SW-6-5 (0.619%) decreased, but the decrease was less than that of hesperidin. In terms of the PMF / total flavonoid ratio, R-0 was 0.153, S-6 increased to 0.223 (+45.8%), W-5 increased to 0.243 (+58.8%), and SW-6-5 reached the highest value of 0.318 (an increase of 107.8% compared to R-0, 42.6% compared to S-6, and 30.9% compared to W-5). Regarding the norihesperidin / citrusperidin ratio, R-0 was 2.895, S-6 was 2.433, W-5 was 2.728, and SW-6-5 (… Figure 11 The value of SW-5 (abbreviated as SW-5) dropped to 2.100, the lowest among all samples.

[0071] Comprehensive comparison shows that steaming alone (S-6) can increase the PMF / total flavonoid ratio by 45.8%, but only decrease hesperidin by 34.3%, indicating incomplete debittering. Washing alone (W-5) can decrease hesperidin by 42.4% and increase the PMF / total flavonoid ratio by 58.8%, but its regulatory capacity is limited. Steaming plus rinsing five times (SW-6-5) achieves the maximum reduction in hesperidin (68.3%) while reaching the highest PMF / total flavonoid ratio (0.318) and the lowest Chuan / Citrus ratio (2.100), fully demonstrating the synergistic effect of steaming and rinsing. Therefore, SW-6-5 is the optimal process condition for debittering Da Hong Pao tangerine peel.

[0072] 5. Characteristic spectrum determination 5.1 Determination of the determination method 5.1.1 Chromatographic conditions and system suitability test Using octadecylsilane-bonded silica gel as the packing material (column length 100 mm, inner diameter 2.1 mm, particle size 2.7 μm); using acetonitrile as mobile phase A and 0.1% formic acid solution as mobile phase B, gradient elution was performed according to the specifications in the table below; the detection wavelength was 330 nm. The theoretical plate number, calculated based on the hesperidin peak, should not be less than 2000.

[0073] 5.1.2 Preparation of reference solution Take appropriate amounts of vesenazoline-2, hesperidin, noriheptacortine, and citrus reticulatae reference standards, accurately weigh them, and add methanol to prepare reference solutions with concentrations of 0.1 mg / mL, 0.4 mg / mL, 25 μg / mL, and 20 μg / mL, respectively.

[0074] 5.1.3 Preparation of the test solution Take about 0.2g of coarse powder of Da Hong Pao orange peel (passed through a No. 2 sieve), weigh it accurately, place it in a stoppered conical flask, add 25mL of methanol accurately, stopper tightly, weigh it, sonicate (power 300W, frequency 40kHz) for 45 minutes, cool it, weigh it again, make up the weight loss with methanol, shake well, filter it, and take the filtrate to obtain the product.

[0075] 5.1.4 Determination Method Accurately pipette 2 μl each of the reference solution and the test solution into the liquid chromatograph and determine the result.

[0076] 5.2 Methodological Investigation of Characteristic Spectrum Determination 5.2.1 Chromatographic conditions and system suitability test 5.2.1.1 Flow velocity investigation Under the proposed experimental conditions, the flow rates of 0.2 mL / min, 0.3 mL / min, and 0.4 mL / min were investigated. (See...) Figure 12 Tables 11-12.

[0077] Table 11 Flow velocity assessment - retention time Table 12 Flow velocity study - relative retention time The results in Tables 11 and 12 show that the chromatogram peak shape and separation effect are better when the flow rate is 0.3 mL / min, and the proposed flow rate is 1.0 mL / min.

[0078] 5.2.1.2 Column Temperature Investigation Based on the above-specified experimental conditions, the results were investigated at column temperatures of 25℃, 30℃, and 35℃. (See...) Figure 13 .

[0079] Table 13 Column Temperature Study - Retention Time Table 14 Column Temperature Study - Relative Retention Time The results in Tables 13 and 14 show that the chromatogram peak shape and separation are better when the column temperature is 30℃. The column temperature is tentatively set at 30℃.

[0080] 5.2.1.3 Delayedness Assessment Based on the above-specified experimental conditions, a delay test was conducted. The results are shown below. Figure 14 The results showed that the sample had virtually no chromatographic peaks after 50 minutes, therefore the sample detection time was set at 50 minutes.

[0081] The conditions for determining the characteristic chromatogram of Da Hong Pao orange peel were determined as follows: Octadecylsilane-bonded silica gel was used as the packing material (column length 100 mm, inner diameter 2.1 mm, particle size 2.7 μm); acetonitrile was used as mobile phase A, and 0.1% formic acid solution was used as mobile phase B, with gradient elution as specified in the table below; the flow rate was 0.3 mL / min; the column temperature was 30℃; and the detection wavelength was 330 nm. The theoretical plate number, calculated based on the hesperidin peak, should not be less than 2000.

[0082] The assay involves precisely pipetting 1 μl of both the reference solution and the test solution into a liquid chromatograph and measuring the results.

[0083] 5.3 Methodological Examination 5.3.1 Chromatographic Peak Identification According to the experimental conditions outlined above, prepare the test solution and reference solution of Da Hong Pao orange peel. Locate the characteristic spectral peaks of the Da Hong Pao orange peel. See [link / reference]. Figure 15 .

[0084] The results showed that peak 1 was veselene-2, peak 3 (S1) was hesperidin, peak 8 was norihesperidin, and peak 9 was citrus-penetrogenin. In the following methodological investigation, 10 characteristic peaks in the sample were examined.

[0085] 5.3.2 Precision Test Take the Da Hong Pao orange peel (R-0) sample solution and inject it 6 times consecutively according to the proposed experimental method. Calculate the RSD value of the retention time of each characteristic peak. The results are shown in Tables 15 and 16.

[0086] Table 15 Precision Examination - Retention Time Table 16 Precision Examination - Relative Retention Time As can be seen from the above, the RSD values ​​of the peak area and relative peak area of ​​each characteristic peak in the precision test are all less than 1.0%, indicating that the instrument has good precision.

[0087] 5.3.3 Repeatability Take 6 portions of the Da Hong Pao orange peel (R-0) sample solution and prepare and determine them according to the proposed experimental method. See Tables 17 and 18.

[0088] Table 17 Repeatability Tests - Retention Time Table 18 Repeatability Tests - Relative Retention Time The results showed that the retention time and relative retention time RSD of the six samples were all less than 2.0%, indicating that the method has good reproducibility.

[0089] 5.3.4 Intermediate Precision Based on the experimental conditions outlined above, different personnel (A and B) weighed orange peel (Da Hong Pao) samples (batch number: R-0) at different times (T1 and T2) to prepare test samples for determination. See Tables 19 and 20.

[0090] Table 19 Retention Time for Different Personnel and Times Table 20: Relative Retention Time for Different Personnel and Times of Investigation The results showed that when different personnel measured the same sample at different times, the RSD of the relative retention time of each characteristic peak was 0.00% to 0.54%, indicating good method stability.

[0091] 5.3.5 Stability Test Under the experimental conditions proposed above, the same test solution was taken and the peak area of ​​each index was measured at 0h, 2h, 4h, 6h, 12h and 24h respectively. The results are shown in Tables 21 and 22.

[0092] Table 21 Stability Study - Retention Time Table 22 Stability Study - Relative Retention Time The results showed that under the experimental conditions, the RSD% of each index was below 1%, and the test solution had good stability within 24 hours.

[0093] The results above show that the RSD of the relative retention times of each characteristic peak meets the requirements in all the above tests, indicating that the method is effective. These 10 characteristic peaks will be included in subsequent investigations.

[0094] 5.4 Verification of Sample Characteristic Spectra According to the established chromatographic conditions, characteristic chromatograms were determined for 14 batches of Da Hong Pao orange peel samples. Using the original sample (R-0) as a reference, 10 common characteristic peaks (peak 1 to peak 10) were identified. Figure 16 As shown. Furthermore, a new peak was detected at 15.13 min in the steamed samples (S-2~S-6 and SW-6-1). Figure 16 (Marked in red) This peak was not observed in the original sample, the sample that was only rinsed, or the sample that was rinsed more than twice after steaming. The retention times and relative retention times of the characteristic peaks of each sample (with hesperidin as a reference) are shown in Tables 23 and 24.

[0095] Table 23 Retention times of chromatographic peaks in Da Hong Pao orange peel samples Table 24 Relative retention times of chromatographic peaks in Da Hong Pao orange peel samples To further visualize the relative changes in the peak areas of each characteristic peak, with the peak areas of the original sample set to 100%, the relative percentages of each characteristic peak in the remaining samples were calculated and a heatmap was plotted. See [link / description]. Figure 17Green indicates a decrease in relative percentage content, yellow indicates no change, and red indicates an increase. The results show that the new peak after steaming only appears in the steamed samples and those washed once after steaming, and disappears completely after two washes. Peaks 1 (Vicine-2), 2, and 4 are generally green (decreasing) in all treatment groups, with all three decreasing to 0% after steaming and rinsing twice. Peaks 9 (hesperidin) and 10 are red (increasing) in most treatment groups. This indicates that the steaming method combined with alternating hot and cold water rinsing can selectively reduce the initial bitterness-related peaks and significantly increase the relative content of polymethoxyflavonoids.

[0096] Principal component analysis (PCA) was performed on the peak area matrix of 11 characteristic peaks (10 common peaks + new peaks after distillation) from 14 samples to obtain the PCA plot. Figure 18 The results showed that the cumulative contribution rates of the first two principal components were PC1 51.6% and PC2 17.9%, respectively, which could well explain the overall chemical differences of the samples. Samples from different processes showed a clear separation trend in the principal component score space: the original samples formed an independent class; the steamed samples clustered into another class; the rinsed samples and the steamed-rinsed samples could be roughly classified into the same major class, but there were still distinguishable differences between them. These results indicate that steaming, rinsing, and combined steaming-rinsing treatments can all significantly alter the chemical composition of Da Hong Pao orange peel, and the changes in chemical profiles caused by different treatments are directional and distinguishable. There is a synergistic effect between steaming pretreatment and subsequent rinsing, resulting in the chemical characteristics of the final product being between those of steaming and rinsing, but not simply superimposed. This further verifies the unique role of the "steaming + alternating hot and cold water rinsing" process in improving the edible quality of Da Hong Pao orange peel.

[0097] 6. Summary The Da Hong Pao orange peel, processed using a "steaming + alternating hot and cold water rinsing" process, eliminates the need for years of natural aging. In just 1-2 days, the bitterness score of the peel can be reduced from 9.0 to below 1.0, achieving a debittering rate of over 90%. The hesperidin removal rate (68.3%) is significantly higher than that of steaming alone (34.3%) and rinsing alone (42.4%). Although the absolute contents of hesperidin and total PMF both decreased during rinsing, the PMF / total flavonoid ratio increased from 0.153 to 0.318 (+107.8%), indicating a significant increase in the relative proportion of polymethoxyflavonoids in the total flavonoids, effectively optimizing the component ratio. Characteristic chromatographic analysis further validated these changes: the new peaks induced by steaming and the initial bitterness-related chromatographic peaks gradually weakened or disappeared after rinsing, and their trend was highly consistent with the decrease in bitterness score.

[0098] Experimental Example 2: Comparison of Bitterness Removal Processes for Da Hong Pao Orange Peel Orange peel is rich in functional components, but its strong bitterness severely limits its application in food, thus prompting numerous studies on debittering processes. However, different processes vary in their efficiency in removing bitter substances, resulting in significant differences in debittering effects. To avoid inconsistent component changes due to process differences, which could lead to redundant studies on debittering effects, this study compares the debittering effects of existing orange peel processing techniques.

[0099] I. Comparison with existing steaming processes The optimal steaming process described in Xiong Haijun's "Processing Technology, Quality Standards and Pharmacodynamics of Steamed Tangerine Peel" was used to analyze the debittering effect of Da Hong Pao tangerine peel: 1. Method Take the same batch of Da Hong Pao orange peel as in Experiment 1, add 30 mL of water per 100 g, moisten for 40 min, steam for 3 h, remove and let cool slightly, cut into strips, and dry at low temperature. Use the multi-component content determination method in Experiment 1 for debittering effect analysis. At the same time, set up steaming for 1 h and 2 h after moistening as time gradient controls.

[0100] 2. Results See Table 25.

[0101] Table 25 Effects of different steaming processes on the components of Da Hong Pao orange peel The results show that: (1) In terms of debittering effect, the hesperidin content of the 3h steamed after moistening was 3.080%, which was 26.5% lower than the original sample (4.192%); while the content of the 6h steamed without moistening was 2.755%, which was 34.3% lower. Compared with the further reduction to 1.328% and a decrease of 68.3% in the "6h steaming + 5 alternating hot and cold water rinsing" in Experiment Example 1, the moistening pretreatment did not improve the debittering efficiency of Da Hong Pao orange peel. The key to improving the debittering efficiency is to rinse with alternating hot and cold water after steaming.

[0102] (2) Regarding the PMF / total flavonoid ratio, the ratio of PMF without humidification continued to rise from 0.153 to 0.223 (+45.8%), while the ratio of PMF after humidification reached 0.199 after 2 hours and then dropped back to 0.196 after 3 hours, indicating that humidification disrupted the continuous enrichment trend of PMF.

[0103] (3) Regarding the ratio of hesperidin / citrus peel, the ratio dropped from 2.895 to 2.433 (-15.9%) without moistening and steaming, while it rose to 2.947 after moistening and steaming for 3 hours, even slightly higher than the original value, indicating that moistening caused the control of the component ratio to deviate.

[0104] (4) Regarding the changes in hesperidin content, Xiong Haijun et al. reported that the hesperidin content of red mandarin oranges decreased after steaming (0.34%→0.31%). In this study, the Da Hong Pao mandarin orange variety was steamed after being moistened using the same method. With the extension of steaming time, the hesperidin content did not change much. After steaming for 3 hours, it only decreased slightly compared with the original sample (0.195%→0.190%), indicating that the processing technology affects the change in hesperidin content due to varietal differences. At the same time, for the Da Hong Pao mandarin orange variety, steaming after moistening had a limited effect on the hesperidin content, but direct steaming without moistening significantly increased the hesperidin content. After steaming for 6 hours, the content increased from 0.195% to 0.231%, a relative increase of 18.46%. It is speculated that moistening inhibited the release of hesperidin, while direct steaming was conducive to its retention and enrichment.

[0105] The above results indicate that the moistening and steaming process has limited debittering effect and poor process stability on the Da Hong Pao variety. Direct steaming without moistening is crucial for the Da Hong Pao variety, as it can increase the hesperidin content and optimize the debittering effect. Different processes need to be adapted for different citrus varieties.

[0106] II. Comparison with existing debittering processes Japanese literature (Akiko Fukuyama et al., Miyazaki Prefectural Industrial Technology Center, 2013) addresses Hinata Natsu ( Citru stamurana Three traditional methods for removing bitterness from the peel of the *Hort.* variety were studied: ① boiling in 20 times its volume of boiling water for 5 minutes, followed by soaking in clean water for 1 hour; ② boiling in 20 times its volume of boiling 3% salt water for 5 minutes, followed by soaking in clean water for 1 hour; ③ boiling in 20 times its volume of boiling water for 5 minutes, repeated 3 times. Method ① showed the best bitterness removal effect while preserving flavor and was recommended as the most suitable method for this variety. Following the best method and its adjustments reported in this literature, the peels of the same batch as in Experiment 1 were treated, and their bitterness removal effect was compared with the process described in Experiment 1. The results are shown in Table 26.

[0107] Table 26 Effects of different debittering processes on the components of Da Hong Pao orange peel The results above show that: 1) Regarding the debittering effect, the hesperidin content of the Japanese literature method (boiling for 5 minutes + soaking for 1 hour) was 3.32%, only 20.8% lower than the original sample (4.19%); steaming for 6 hours + boiling for 5 minutes + soaking for 1 hour resulted in 2.16%, a decrease of 48.4%; steaming for 6 hours + rinsing with cold water 5 times resulted in 1.56%, a decrease of 62.8%; while the optimal process in Experiment 1 (steaming for 6 hours + alternating rinsing 5 times) resulted in 1.33%, a decrease of 68.3%, the largest decrease among all treatments. Regarding the bitterness score, the Japanese literature method was 6.5±0.80, steaming for 6 hours + boiling for 5 minutes + soaking for 1 hour resulted in 2.5±0.70, steaming for 6 hours + rinsing with cold water 5 times resulted in 1.5±0.60, while the optimal process in Experiment 1 was only 0.6±0.70, with virtually no bitterness, significantly better than the other control groups. These results indicate that the "boiling + soaking" method recommended in Japanese literature has very limited effect on removing bitterness from Da Hong Pao cultivar, while the present invention achieves the best debittering effect through a combination of steaming and alternating rinsing.

[0108] (2) Comparison of post-treatment methods: Based on steaming for 6 hours, the debittering effects of three post-treatment methods were compared: the hesperidin removal rate was 2.16% after boiling for 5 minutes and soaking for 1 hour, with a bitterness score of 2.5; the removal rate was 1.56% after rinsing with cold water 5 times, with a bitterness score of 1.5; and the removal rate was 1.33% after rinsing with alternating rinses 5 times, with a bitterness score of 0.6. The hesperidin removal rate of alternating rinses was 14.7% higher than that of cold water rinses, and the bitterness score was reduced by 60%; it was 38.4% higher than that of boiling + soaking, and the bitterness score was reduced by 76%. This indicates that under the same steaming conditions, the debittering efficiency of hot water-cold water alternating rinses is significantly better than that of cold water rinses and boiling + soaking, confirming the superiority of alternating rinses in actively washing away bitter components using the principle of thermal expansion and contraction.

[0109] Based on the above analysis, the "boiling for 5 minutes + soaking for 1 hour" method recommended in Japanese literature has limited effect on removing bitterness from Da Hong Pao tangerine peel (hesperidin residue rate 79.2%, bitterness score 6.5). However, the combined process of "steaming + alternating hot and cold water rinsing" reduced hesperidin to 1.33% (residual rate 31.7%) and bitterness score to 0.6, demonstrating a significantly better debittering effect than the previous methods. This proves that the combined process has significant advantages in debittering Da Hong Pao tangerine peel.

Claims

1. A rapid processing method for improving the edible quality of Da Hong Pao orange peel, characterized in that: Includes the following steps: Take fresh Da Hong Pao orange peel, steam it for 2-6 hours, cool it, rinse it with hot water first, then rinse it with cold water, repeat this process of rinsing with hot and cold water 3-5 times, and then dry it.

2. The rapid processing method according to claim 1, characterized in that: The fresh Da Hong Pao orange peel refers to the peel of Da Hong Pao tangerines that has been washed with clean water and impurities removed while still maintaining its freshness.

3. The rapid processing method according to claim 2, characterized in that: The temperature of the clean water is below 25°C.

4. The rapid processing method according to claim 1, characterized in that: During the steaming process, the orange peel is laid out in a single layer, with the thickness of the layer controlled to not exceed 5 cm, and steamed at 100°C under normal pressure saturated steam conditions.

5. The rapid processing method according to claim 4, characterized in that: The steaming time is 4-6 hours, during which the food is turned 1-3 times.

6. The rapid processing method according to claim 5, characterized in that: The steaming time is 6 hours.

7. The rapid processing method according to claim 1, characterized in that: The cooling process involves natural cooling to 30-40°C.

8. The rapid processing method according to claim 1, characterized in that: The hot water rinsing temperature is 90~100℃, and the rinsing time is 0.5~1.5min; the cold water rinsing temperature is 4-25℃, and the rinsing time is 0.5~1.5min.

9. The rapid processing method according to claim 1, characterized in that: The water is rinsed repeatedly with alternating hot and cold water five times.

10. The rapid processing method according to claim 1, characterized in that: The drying process involves drying at 60-70℃ for 1-2 hours, then at 40-50℃ for 8-14 hours, and finally at 30-40℃ for 1-2 hours.

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