Citrus peel processing method

Abstract

The invention relates to the technical field of new tea drinks, and particularly discloses a processing method and a preparation method of orange peel. The debitterizing treatment liquid is used for treating the orange peel, pectin macromolecules in the orange peel are degraded into pectin with low molecular weight by pectinase, dissolution of typical bitter substances such as pectin, naringin and limonin compounds is promoted, and finally the crushed orange peel product with low bitter substance content is obtained. The orange peel tea prepared from the broken orange peel does not have too strong bitter taste after being brewed, but can be better matched with the tea taste, so that the drinking experience of the orange peel tea is improved.

Description

Technical Field

[0001] The present application relates to the technical field of new tea beverages, and more specifically, to a method for processing citrus peel. Background Art

[0002] Citrus is a plant of the genus Citrus in the subfamily Citrus of the family Rutaceae. The global annual production is nearly 100 million tons. The main production areas of citrus are distributed in tropical and subtropical areas, and my country is one of the main production areas of citrus. Citrus contains a variety of bioactive compounds such as flavanones, phenolic acids, limonin, L-ascorbic acid, carotenoids, volatile terpenes, etc. It has attractive colors and pleasant flavors and aromas. Therefore, it has always been popular with consumers and has become an important source of nutrition for Chinese residents. In addition to the flesh of citrus, its peel also has medicinal value. The Chinese medicine tangerine peel is processed from citrus peel (hereinafter referred to as tangerine peel).

[0003] Although tangerine peel can be used as medicine, the demand for tangerine peel in the traditional Chinese medicine industry is limited, and not all tangerine peel can be used to process dried orange peel. Behind the huge annual output of citrus, a large amount of tangerine peel is still discarded. Tangerine peel contains pigments, pectin, dietary fiber, secondary metabolites and other ingredients, which have certain utilization value and have broad development prospects as a functional food resource.

[0004] In the related art, there is a kind of tangerine peel tea, which is prepared according to the following steps: (1) picking tangerines and washing them, then peeling the tangerine peel and washing them again, drying the washed tangerine peel, kneading and drying it, and then cutting it into strips; (2) mixing the cut tangerine peel strips with tea leaves evenly, and then putting them in a frying pan and frying them over a low heat, constantly turning them during frying to ensure that the tangerine peel strips and tea leaves are fully heated; (3) taking out the mixture of tangerine peel strips and tea leaves and drying them to obtain tangerine peel tea, and then sealing and packaging them.

[0005] Regarding the above-mentioned related technologies, the inventors believe that although tangerine peel and tea leaves are compounded and processed in the related technologies to obtain tangerine peel tea, the bitter substances such as naringin and limonin compounds contained in the tangerine peel cannot be fully removed during the processing. Therefore, the tangerine peel tea will have a strong bitter taste after being brewed with hot water, and the drinking experience is poor. Summary of the invention

[0006] In the related art, tangerine peel tea has a strong bitter taste after being brewed in hot water, and the drinking experience is poor. In order to improve this defect, the present application provides a tangerine peel processing method.

[0007] The present application provides a method for processing tangerine peel, which adopts the following technical solution: A method for processing tangerine peel comprises the following steps: (1) harvesting citrus fruits, spreading the citrus fruits to dry, and then refrigerating them for later use; (2) peeling citrus fruits, then soaking the obtained fresh citrus peel in a debittering treatment solution, heating the peel in a water bath, and then drying the peel to obtain dried citrus peel; the debittering treatment solution comprises pectinase and a debittering agent, and the debittering agent comprises cellulose triacetate; (3) removing impurities and debris from the dried tangerine peel, and chopping the dried tangerine peel to obtain chopped tangerine peel after removing impurities; (4) The crushed tangerine peel is cleaned, disinfected, sterilized and deodorized, and then placed in a sealed packaging bag to complete the processing of the tangerine peel.

[0008] By adopting the above technical scheme, the present application uses a debittering treatment liquid to treat the tangerine peel. During the treatment process, pectinase can degrade the β-1,4-glucoside bond in the pectin molecule, thereby decomposing the pectin macromolecules in the dry tangerine peel into low molecular weight pectin, which will gradually dissolve from the tangerine peel during the water bath heating process. The dissolution of pectin can promote the release of typical bitter substances such as naringin and limonin compounds, and the triacetylcellulose in the debittering agent and the dissolved low molecular weight pectin can synergistically adsorb these bitter substances, so that the content of bitter substances in the tangerine peel can be effectively reduced, and finally a crushed tangerine peel product with a low content of bitter substances is obtained. Due to the reduced content of bitter substances, the tangerine peel tea made from this crushed tangerine peel no longer has an overly strong bitter taste after brewing, but can better match the tea flavor, which helps to improve the drinking experience of tangerine peel tea.

[0009] Preferably, the dosage of the pectinase is 1-1.5% of the weight of the fresh tangerine peel.

[0010] By adopting the above technical scheme, the present application optimizes the dosage range of pectinase, which helps to promote the degradation and dissolution of pectin, reduces the bitterness of tangerine peel, and helps to improve the drinking experience of tangerine peel tea.

[0011] Preferably, the components in the debittering solution also include cellulase and hemicellulase.

[0012] By adopting the above-mentioned technical scheme, the present application adds cellulase and hemicellulase to the debittering treatment liquid. While cellulase and hemicellulase degrade the cellulose and hemicellulose in the tangerine peel, they can also promote the degradation of pectin by pectinase, indirectly promoting the dissolution of pectin, thereby further reducing the content of bitter substances in the tangerine peel, and helping to improve the drinking experience of tangerine peel tea.

[0013] Preferably, the dosage of the cellulase and hemicellulase is 0.7-1.2% of the weight of the fresh tangerine peel.

[0014] By adopting the above technical solution, the present application optimizes the dosage range of cellulase and hemicellulase, which helps to reduce the content of bitter substances in tangerine peel and improve the drinking experience of tangerine peel tea.

[0015] Preferably, the water bath heating time is 30-40 min.

[0016] By adopting the above technical solution, the present application optimizes the time range of water bath heating, which helps to reduce the bitter substance content of tangerine peel and improve the drinking experience of tangerine peel tea.

[0017] Preferably, the water bath heating temperature is 45-60°C.

[0018] By adopting the above technical solution, the present application optimizes the temperature range of water bath heating, which helps to reduce the content of bitter substances in tangerine peel and improve the drinking experience of tangerine peel tea.

[0019] Preferably, the debittering agent further comprises magnesium silicate, and the magnesium silicate is pretreated according to the following method before use: The magnesium silicate is ground into powder, then heated and activated at 550-650℃ for 2-3h, and then waited for natural cooling to complete the pretreatment of the magnesium silicate.

[0020] By adopting the above technical solution, although the magnesium silicate powder has pores in its natural state, the pores are blocked by impurities and cannot play an adsorption role. After pretreatment with heating and activation at 550-650°C, the impurities in the pores of magnesium silicate are removed, so that magnesium silicate can have a good adsorption effect on the bitter substances dissolved in the tangerine peel. Under the synergistic effect of activated magnesium silicate, cellulose triacetate, and pectin, the bitter substances dissolved in the tangerine peel can be quickly adsorbed, so that the dissolution-adsorption process can be carried out with higher efficiency, so that a tangerine peel with a lighter bitterness can be obtained in the same processing time.

[0021] Preferably, the debittering agent further comprises β-cyclodextrin.

[0022] By adopting the above technical solution, bitter substances such as naringin and limonin can be embedded in the cavity structure of the β-cyclodextrin molecule, and the bitter effects of these molecules can be shielded by forming inclusion compounds. Through the synergistic effect of β-cyclodextrin, cellulose triacetate, pectinase and other components, the bitterness of tangerine peel tea after brewing can be more fully reduced, thereby improving the drinking experience of tangerine peel tea.

[0023] Preferably, the debittering solution further comprises at least one of sodium chloride and sucrose.

[0024] By adopting the above technical solution, the addition of sodium chloride and sucrose can increase the osmotic pressure of the debittering solution, accelerate the dissolution of bitter substances such as naringin, and help to obtain tangerine peel with less bitterness.

[0025] Preferably, in step (2) of the method, the debittering liquid is subjected to ultrasonic treatment while being heated in a water bath.

[0026] By adopting the above technical solution, ultrasonic treatment can improve the catalytic enzymolysis of pectinase, promote the dissolution of pectin and bitter substances, and help reduce the bitterness of tangerine peel.

[0027] In summary, this application has the following beneficial effects: 1. The present application uses a debittering treatment liquid to treat tangerine peel, and uses pectinase to degrade pectin macromolecules in the tangerine peel into low molecular weight pectin, thereby promoting the dissolution of pectin and typical bitter substances such as naringin and limonin compounds, and finally obtains a crushed tangerine peel product with a low content of bitter substances. The tangerine peel tea made from the crushed tangerine peel no longer has an overly strong bitter taste after brewing, but can better match the tea flavor, thereby improving the drinking experience of tangerine peel tea.

[0028] 2. In the present application, hemicellulase and cellulase are preferably used in combination with pectinase. While cellulase and hemicellulase degrade cellulose and hemicellulose in tangerine peel, they can also promote the degradation of pectin by pectinase, indirectly promoting the dissolution of pectin, thereby further reducing the content of bitter substances in tangerine peel and helping to improve the drinking experience of tangerine peel tea.

[0029] 3. The present application uses high-temperature activated magnesium silicate and β-cyclodextrin to adsorb bitter substances, and through synergistic effects, the dissolution-adsorption process can be carried out with higher efficiency, so that orange peel with less bitterness can be obtained within the same processing time.

[0030] 4. The present application adds sodium chloride and sucrose to the debittering solution. The addition of sodium chloride and sucrose can increase the osmotic pressure of the debittering solution, accelerate the dissolution of bitter substances such as naringin, and help obtain a tangerine peel product with a lighter bitter taste. DETAILED DESCRIPTION

[0031] The present application is further described in detail below in conjunction with examples and comparative examples. The raw materials involved in the present application can all be obtained commercially. Example

[0032] Examples 1-5 The following description is given by taking Example 1 as an example.

[0033] Example 1 In this embodiment, the citrus fruit is selected from the mature fruit of "Citrus reticulate Chach"; this embodiment also relates to a debittering treatment solution, which is prepared with a citric acid-sodium citrate buffer solution with a pH of 5.0, and the components added during the preparation process include pectinase and a debittering agent. Among them, the enzyme activity of the pectinase is 50000U / g, and the debittering agent is selected from cellulose triacetate (CAS: 9012-09-3); the amount of pectinase used is 0.8% of the weight of the fresh citrus peel, and the amount of cellulose triacetate used is 1.5% of the weight of the fresh citrus peel.

[0034] This embodiment provides a method for processing tangerine peel, comprising the following steps: (1) harvesting citrus fruits, spreading the citrus fruits to dry until there is no moisture on the surface, and then refrigerating them at 3° C. for later use; (2) peeling the citrus fruit by using the three-knife method, wherein the citrus fruit is peeled by cutting three times vertically from the top of the fruit to the citrus fruit with the pedicle facing downward, leaving the pedicle connected, and peeling the three petals; soaking the obtained fresh citrus peel in a debittering treatment solution at a weight ratio of 1:10, heating it in a water bath at 40° C. for 25 minutes, and then drying it to obtain dry citrus peel; (3) removing impurities and debris from the dried tangerine peel, and chopping the dried tangerine peel to obtain chopped tangerine peel after removing impurities; (4) The crushed tangerine peel is cleaned, disinfected, sterilized and deodorized, and then placed in a sealed packaging bag to complete the processing of the tangerine peel.

[0035] Example 2 The main difference between this embodiment and embodiment 1 is that the dosage of pectinase is 1% of the weight of the fresh tangerine peel.

[0036] Example 3 The main difference between this embodiment and embodiment 1 is that the dosage of pectinase is 1.2% of the weight of fresh tangerine peel.

[0037] Example 4 The main difference between this embodiment and embodiment 1 is that the dosage of pectinase is 1.5% of the weight of fresh tangerine peel.

[0038] Example 5 The difference between this embodiment and embodiment 4 is that the components in the debittering treatment liquid also include cellulase and hemicellulase, the enzymatic activity of cellulase is 20000U / g, the enzymatic activity of hemicellulase is 70000U / g, the weight ratio of cellulase to hemicellulase is 2:1, and the total dosage of cellulase and hemicellulase is 0.5% of the weight of fresh tangerine peel.

[0039] Example 6 The difference between this embodiment and embodiment 5 is that the total amount of cellulase and hemicellulase used is 0.7% of the weight of the fresh orange peel.

[0040] Example 7 The difference between this embodiment and embodiment 5 is that the total amount of cellulase and hemicellulase used is 0.9% of the weight of the fresh tangerine peel.

[0041] Example 8 The difference between this embodiment and embodiment 5 is that the total amount of cellulase and hemicellulase used is 1.2% of the weight of the fresh tangerine peel.

[0042] Example 9 The difference between this embodiment and embodiment 8 is that in step (2) of the tangerine peel processing method, the water bath heating time is 30 minutes.

[0043] Example 10 The difference between this embodiment and embodiment 8 is that in step (2) of the tangerine peel processing method, the water bath heating time is 35 minutes.

[0044] Embodiment 11 The difference between this embodiment and embodiment 8 is that in step (2) of the tangerine peel processing method, the water bath heating time is 40 minutes.

[0045] Example 12 The difference between this embodiment and embodiment 11 is that in step (2) of the tangerine peel processing method, the water bath heating temperature is 45°C.

[0046] Embodiment 13 The difference between this embodiment and embodiment 11 is that in step (2) of the tangerine peel processing method, the water bath heating temperature is 55°C.

[0047] Embodiment 14 The difference between this embodiment and embodiment 11 is that in step (2) of the tangerine peel processing method, the water bath heating temperature is 60°C.

[0048] Embodiment 15 The difference between this embodiment and embodiment 14 is that the debittering agent also includes magnesium silicate, and the amount of magnesium silicate used is 1% of the weight of the fresh tangerine peel. The magnesium silicate is pretreated as follows before use: the magnesium silicate is ground into powder, then heated and activated at 550°C for 2h, and then waited for natural cooling to complete the pretreatment of the magnesium silicate.

[0049] Example 16 The difference between this embodiment and embodiment 15 is that the magnesium silicate powder is heated and activated at 600° C. for 2.5 hours.

[0050] Embodiment 17 The difference between this embodiment and embodiment 15 is that the magnesium silicate powder is heated and activated at 650° C. for 3 hours.

[0051] Embodiment 18 The difference between this embodiment and embodiment 17 is that the debittering agent further comprises β-cyclodextrin, and the amount of β-cyclodextrin used is 0.5% of the weight of the fresh tangerine peel.

[0052] Embodiment 19 The difference between this embodiment and embodiment 18 is that the debittering solution also includes sodium chloride, and the amount of sodium chloride used is 10% of the weight of the fresh tangerine peel.

[0053] Embodiment 20 The difference between this embodiment and embodiment 19 is that the debittering liquid also includes sucrose, and the amount of sucrose used is 10% of the weight of the fresh tangerine peel.

[0054] Embodiment 21 The difference between this embodiment and embodiment 20 is that in step (2) of the tangerine peel processing method, the debittering solution is ultrasonically treated at an intensity of 4.5 W / mL for the first 15 minutes of water bath heating.

[0055] Comparative Example Comparative Example 1 The difference between this comparative example and Example 1 is that no debittering agent and pectinase are added to the debittering liquid.

[0056] Comparative Example 2 The difference between this comparative example and Example 3 is that no debittering agent is added to the debittering treatment liquid.

[0057] Comparative Example 3 The difference between this comparative example and Example 3 is that no pectinase is added to the debittering solution.

[0058] Performance testing methods The tangerine peels and Yunnan Pu'er tea obtained in the examples and comparative examples were mixed in a weight ratio of 3:2, and then brewed with 80° C. boiled water as the test sample, wherein the total weight of the tangerine peels and Yunnan Pu'er tea was 1 / 30 of the weight of the boiled water.

[0059] The nine-point scale method was used to conduct sensory evaluation of the samples to be tested. The scoring item was bitterness scoring, 1 point means that the bitterness is too strong, which seriously affects the drinking experience; 5 points means that the bitterness still exists, but the negative impact on the drinking experience is no longer obvious; 9 points means that the bitterness concentration is appropriate and has no negative impact on the drinking experience. Each group has 10 judges, and the average score of the 10 judges is taken as the final score of the group. The results are shown in Table 2.

[0060] Table 2 Sensory evaluation results sample score sample score Example 1 5.6 Embodiment 13 6.7 Example 2 5.7 Embodiment 14 6.8 Example 3 5.8 Embodiment 15 7.1 Example 4 5.8 Example 16 7.2 Example 5 5.9 Embodiment 17 7.2 Example 6 6.0 Embodiment 18 7.4 Example 7 6.2 Embodiment 19 7.6 Example 8 6.3 Embodiment 20 7.9 Example 9 6.5 Embodiment 21 8.2 Example 10 6.5 Comparative Example 1 3.9 Embodiment 11 6.6 Comparative Example 2 4.3 Example 12 6.7 Comparative Example 3 4.0 Combining Example 1 and Comparative Examples 1-3 and Table 2, it can be seen that the sensory score measured in Example 1 has reached more than 5 points, while the sensory evaluation results of Comparative Examples 1-3 are all below 5 points. This is because after being treated with the debittering treatment liquid, pectinase degrades the pectin macromolecules in the tangerine peel into low molecular weight pectin, which promotes the dissolution of pectin and typical bitter substances such as naringin and limonin compounds, and finally obtains a crushed tangerine peel product with a low content of bitter substances. The tangerine peel tea made from this crushed tangerine peel no longer has an overly strong bitter taste after brewing, but can better match the tea flavor, thereby improving the drinking experience of tangerine peel tea. However, due to the lack of synergistic effects of pectinase and debittering agent in Comparative Examples 1-3, the tangerine peel retains more bitter substances, affecting the final drinking experience.

[0061] Combining Example 1 and Examples 2-4 with Table 2, it can be seen that the sensory scores measured in Examples 2-4 are higher. This is because when the dosage of pectinase is 1-1.5% of the weight of fresh tangerine peel, it helps to promote the degradation and dissolution of pectin, reduce the bitterness of tangerine peel, and thus help to improve the drinking experience of tangerine peel tea.

[0062] Combining Example 4 and Example 5 with Table 2, it can be seen that the sensory score measured in Example 5 is higher. This is because while cellulase and hemicellulase degrade cellulose and hemicellulose in tangerine peel, they can also promote the degradation of pectin by pectinase, indirectly promoting the dissolution of pectin, thereby further reducing the bitter substance content in tangerine peel, which helps to improve the drinking experience of tangerine peel tea.

[0063] Combining Examples 5-8 and Table 2, it can be seen that the sensory scores measured in Examples 6-8 are relatively high, indicating that when the dosage of cellulase and hemicellulase is 0.7-1.2% of the weight of fresh tangerine peel, it helps to reduce the bitter substance content of tangerine peel and improve the drinking experience of tangerine peel tea.

[0064] Combining Example 8, Examples 9-11 and Table 2, it can be seen that the sensory scores measured in Examples 9-11 are higher, indicating that when the water bath heating time is 30-40 minutes, it helps to reduce the bitter substance content of tangerine peel and improve the drinking experience of tangerine peel tea.

[0065] Combining Example 11, Examples 12-14 and Table 2, it can be seen that the sensory scores measured in Examples 12-14 are higher, indicating that when the water bath heating temperature is 45-60° C., it helps to reduce the bitter substance content of tangerine peel and improve the drinking experience of tangerine peel tea.

[0066] Combining Example 14, Examples 15-17 and Table 2, it can be seen that the sensory scores measured in Examples 15-17 are all higher than those in Example 14. This is because after the pretreatment of heating activation at 550-650°C, the impurities in the pores of magnesium silicate are removed, so that magnesium silicate can have a good adsorption effect on the bitter substances dissolved in the tangerine peel. Under the synergistic effect of activated magnesium silicate, triacetyl cellulose and pectin, the bitter substances dissolved in the tangerine peel can be quickly adsorbed, so that the dissolution-adsorption process can be carried out with higher efficiency, so that a tangerine peel with a lighter bitter taste can be obtained within the same processing time.

[0067] Combining Example 17 and Example 18 with Table 2, it can be seen that the sensory score measured in Example 18 is higher than that in Example 17. This is because bitter substances such as naringin and limonin can be embedded in the cavity structure of the β-cyclodextrin molecule, and the bitter effects of these molecules are shielded by forming inclusion compounds. The synergistic effect of β-cyclodextrin, cellulose triacetate, pectinase and other components can more fully reduce the bitterness of the tangerine peel tea after brewing, thereby improving the drinking experience of the tangerine peel tea.

[0068] Combining Example 18, Examples 19-20 and Table 2, it can be seen that the sensory scores measured in Examples 19-20 are higher than those in Example 18. This is because the addition of sodium chloride and sucrose can increase the osmotic pressure of the debittering solution, accelerate the dissolution of bitter substances such as naringin, and help obtain tangerine peel with a lighter bitter taste.

[0069] Combining Example 20, Example 21 and Table 2, it can be seen that the sensory score measured in Example 21 is higher than that in Example 20. This is because the ultrasonic treatment can improve the catalytic enzymolysis of pectinase, promote the dissolution of pectin and bitter substances, and help reduce the bitterness of tangerine peel.

[0070] The above embodiments are merely explanations of the present application and are not limitations of the present application. After reading this specification, those skilled in the art may make modifications to the embodiments of the present application without any creative contribution as needed. However, as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A method for processing tangerine peel, characterized in that: The following steps are involved: (1) harvesting citrus fruits, spreading them out to dry, and then refrigerating them for later use; (2) peeling citrus fruits, then soaking the obtained fresh citrus peel in a debittering treatment liquid, heating the peel in a water bath, and then drying the peel to obtain dried citrus peel; the debittering treatment liquid comprises pectinase and a debittering agent, and the debittering agent comprises cellulose triacetate; (3) removing impurities and debris from the dried tangerine peel, and chopping the dried tangerine peel into small pieces, thereby obtaining chopped tangerine peel after removing impurities; (4) The crushed tangerine peel is cleaned, dewormed, disinfected and deodorized, then placed in a sealed packaging bag to complete the processing of the tangerine peel.

2. The method for processing tangerine peel according to claim 1, characterized in that: The dosage of the pectinase is 1-1.5% of the weight of the fresh tangerine peel.

3. The method for processing tangerine peel according to claim 2, characterized in that: The components in the debittering solution also include cellulase and hemicellulase.

4. The method for processing tangerine peel according to claim 3, characterized in that: The dosage of the cellulase and hemicellulase is 0.7-1.2% of the weight of the fresh tangerine peel.

5. The method for processing tangerine peel according to claim 1, characterized in that: The water bath heating time is 30-40 minutes.

6. The method for processing tangerine peel according to claim 5, characterized in that: The water bath heating temperature is 45-60°C.

7. The method for processing tangerine peel according to claim 1, characterized in that: The debittering agent also includes magnesium silicate, and the magnesium silicate is pretreated according to the following method before use: The magnesium silicate is ground into powder, then heated and activated at 550-650℃ for 2-3h, and then waited for natural cooling to complete the pretreatment of the magnesium silicate.

8. The method for processing tangerine peel according to claim 7, characterized in that: The debittering agent also includes β-cyclodextrin.

9. The method for processing tangerine peel according to claim 1, characterized in that: The components of the debittering solution also include at least one of sodium chloride and sucrose.

10. The method for processing tangerine peel according to claim 1, characterized in that: In step (2) of the method, the debittering liquid is ultrasonically treated while being heated in a water bath.