Production process for improving content of protocatechuic acid in Laiyang pear syrup

Abstract

The invention belongs to the technical field of food, and particularly relates to a production process for increasing the content of protocatechuic acid in Laiyang pear syrup. An ultrasonic extraction technology is applied to extraction of protocatechuic acid, and the specific technological process comprises the steps of raw material selection, selection, cleaning, crushing, color protection, squeezing, pear residue ultrasonic extraction, filtration, decoction, filtration, concentration, detection, filling, packaging, warehousing and the like. The protocatechuic acid extracted by an ultrasonic extraction technology is processed and concentrated together with squeezed juice, so that the content of the protocatechuic acid in the Laiyang pear syrup is increased, and the product efficacy is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of food, and particularly relates to a production process for improving the protocatechuic acid content of Laiyang Cili Paste. Background Art

[0002] Laiyang Ci Pear, also known as Laiyang Chi Pear, commonly known as Laiyang Pear, is an excellent variety of white pear system commonly cultivated in Shandong. It is mainly produced in Laiyang City. The fruit is large, and the general commercial fruit weight is 220-280 grams, and the large one is more than 800 grams. The unpinched calyx is oval to spindle-shaped, and the top of the pinched calyx fruit is swollen and obovate, short gourd-shaped, and the shape of the fruit varies greatly due to different fruiting parts. The peel is thin, yellow-green or yellow with a slight green. Laiyang Pear is a famous specialty of Shandong Province, with a planting history of more than 400 years. It was listed as a royal tribute in the Ming Dynasty. Laiyang Pear has a large and thin skin, tender flesh, crisp and delicious, sweet but not greasy, and a unique flavor. The reason why Laiyang pear is considered the best pear is because of its excellent production area. Laiyang pear grows in a vast oil sand land by the Wulong River. This fine sand soil is loose, permeable, rich in mica, with a large temperature difference between day and night. The natural ecological conditions are very conducive to the formation and accumulation of fruit nutrients. The sugar content of Laiyang pear is as high as 14.76%, which is 2%-3% higher than that of ordinary pears. This creates the unique charm of Laiyang pear and its deep-processed products.

[0003] Pear paste is a traditional Chinese medicinal food, mainly made of pears, with other medicinal materials or auxiliary materials, and boiled and concentrated into a paste. Pear paste has a long history and is widely used in traditional Chinese medicine health care and diet therapy.

[0004] Pear peel is rich in protocatechuic acid, chlorogenic acid and other ingredients. Protocatechuic acid (PCA), also known as 3,4-dihydroxybenzoic acid, is a phenolic acid substance naturally present in many vegetables and fruits, and is an effective active ingredient in many traditional Chinese medicines (such as Salvia miltiorrhiza, Hibiscus, etc.). Protocatechuic acid is a water-soluble phenolic acid component and an active substance in many traditional Chinese medicines. It not only has pharmacological activities such as anti-platelet aggregation, reducing myocardial oxygen consumption, improving myocardial oxygen tolerance, slowing heart rate, antibacterial, and analgesia, but also has antioxidant, anti-tumor and neuroprotective effects. In the preparation of conventional pear paste, the content of protocatechuic acid is low, and the peel is also wasted without comprehensive utilization. Summary of the invention

[0005] In view of the above technical problems, the technical problem to be solved by the present invention is to provide a pear paste with a higher protocatechuic acid content and a preparation process thereof.

[0006] Pear peel is rich in protocatechuic acid. In order to provide the content of protocatechuic acid in pear paste, the present invention first applies ultrasonic extraction technology to extract protocatechuic acid, specifically extracting the pear residue after the pear juice is extracted. Further, in order to improve the efficiency of extracting protocatechuic acid from pear residue, enzymatic hydrolysis can be used to perform preliminary enzymatic hydrolysis on the pear residue, so that the protocatechuic acid in the pear residue can be extracted to the maximum extent.

[0007] Furthermore, the present invention provides a production process of pear paste, and the specific process flow includes: raw material selection, picking, cleaning, crushing, color protection, pressing, ultrasonic extraction of pear residue, filtration, boiling, filtration, concentration, testing, filling, packaging, and warehousing.

[0008] The specific process requirements and steps are as follows: 1: Raw material selection: Mainly from the Laiyang Ci pear planting and production center, use fresh Laiyang Ci pears, which must be free of insect pests, rot, and agricultural residues that meet national food hygiene requirements.

[0009] 2: Raw material selection: select out those with insect pests, rotten fruits and impurities.

[0010] 3: Cleaning: Pour the selected Laiyang Ci pears into the fruit cleaning equipment, and use two processes to clean them: bubble cleaning and then spray cleaning. Clean the pears in all directions to ensure that they are clean.

[0011] 4: Crushing: Use a hammer-type stainless steel machine for crushing, and the particles are required to be around 0.5-1.0CM.

[0012] 5: Color protection: Add color protection agent (VC or citric acid) during the crushing process, the addition amount is 0.05-0.1%.

[0013] 6: Pressing: Use a spiral juicer for pressing, the mesh size is 0.1MM, and the pear residue is required to be in a cake shape.

[0014] 7. Ultrasonic extraction: Put the pear residue into the ultrasonic extraction tank, add 20% pure water, turn on the ultrasonic equipment, the temperature is 40-50 degrees, the time is about 30 minutes, turn off the ultrasonic equipment, and extract the juice in the equipment.

[0015] 8: Filtration: Filter the squeezed juice and extracted juice through a vibrating screen (200 mesh filter) and pump them into a stainless steel tank with a stainless steel pump for storage.

[0016] 9: Boiling: Pump the pear juice in the stainless steel tank into the sandwich pot and heat it. Stop heating 30 minutes after boiling.

[0017] 10: Filtration: Filter through 300-mesh filter equipment and pump into storage tank for storage.

[0018] 11: Concentration: Use vacuum low-temperature concentration, the vacuum degree is 0.09 Pa, and the temperature is less than 75 degrees.

[0019] 12: Testing: The product meets the product standard requirements.

[0020] 13: Filling: All filling equipment must be sterilized and qualified before filling. After filling, the product must be commercially sterilized and packaged for storage after passing the test.

[0021] Furthermore, the present invention also provides a process, specifically, adding an enzymatic hydrolysis step of the pear residue before the ultrasonic extraction in step (4). Preferably, the enzymatic hydrolysis of the pear residue is treated with cellulase and pectinase.

[0022] The specific steps of enzymatic hydrolysis of pear residue are as follows: adding 20% ​​pure water by weight of the pear residue to the pear residue, and then adding cellulase and pectinase, the weight of cellulase and pectinase are 0.1-2% and 0.1-3% of the weight of the material respectively; maintaining the temperature at 30-50°C and stirring continuously; the enzymatic hydrolysis time is 1-2h, and then the temperature is raised to 80-90°C.

[0023] Furthermore, in order to save production time, the present invention also provides a process for simultaneously performing ultrasonic extraction and enzymatic hydrolysis treatment; the specific steps are: putting pear residue into an ultrasonic extraction tank, adding pure water with a weight of 20% of the weight of the pear residue, and adding cellulase and pectinase at the same time, wherein the weight of the cellulase and pectinase is 0.1-2% and 0.1-3% of the weight of the material respectively, and stirring continuously, while turning on the ultrasonic equipment at a temperature of 40-50 degrees for 30-60 minutes, turning off the ultrasonic equipment, and extracting the juice in the equipment.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: The Laiyang pear peel is rich in a large amount of protocatechuic acid, chlorogenic acid and other ingredients. The present invention extracts them through ultrasonic extraction technology and processes them together with squeezed juice to concentrate them, thereby increasing the content of protocatechuic acid in Laiyang pear paste and improving the product efficacy. DETAILED DESCRIPTION

[0025] The specific implementation modes of the present invention are described by the following examples, but the protection content of the present invention is not limited thereto.

[0026] Example 1 This embodiment provides a process for preparing pear paste using Laiyang Ci pear, and the specific steps are as follows: 1: Raw material selection: Mainly from the Laiyang Ci pear planting and production center, use fresh Laiyang Ci pears, which must be free of insect pests, rot, and agricultural residues that meet national food hygiene requirements.

[0027] 2: Raw material selection: select out those with insect pests, rotten fruits and impurities.

[0028] 3: Cleaning: Pour the selected Laiyang Ci pears into the fruit cleaning equipment, and use two steps of bubble cleaning followed by spray cleaning to clean the pears in all directions to ensure that they are clean.

[0029] 4: Crushing: Use a hammer-type stainless steel machine for crushing, and the particles are required to be 0.5CM.

[0030] 5: Color protection: Add color protection agent during the crushing process. VC is selected as the color protection agent and the addition amount is 0.05%.

[0031] 6: Pressing: Use a spiral juicer for pressing, the mesh size is 0.1MM, and the pear residue is required to be in a cake shape.

[0032] 7. Ultrasonic extraction: Put the pear residue into the ultrasonic extraction tank, add 20% pure water, turn on the ultrasonic equipment, the temperature is 40 degrees, the time is 30 minutes, turn off the ultrasonic equipment, and extract the juice from the equipment.

[0033] 8: Filtration: Filter the squeezed juice and extracted juice through a vibrating screen (200 mesh filter) and pump them into a stainless steel tank with a stainless steel pump for storage.

[0034] 9: Boiling: Pump the pear juice in the stainless steel tank into the sandwich pot and heat it. Stop heating 30 minutes after boiling.

[0035] 10: Filtration: Filter through 300-mesh filter equipment and pump into storage tank for storage.

[0036] 11: Concentration: Use vacuum low-temperature concentration, the vacuum degree is 0.09 Pa, and the temperature is less than 75 degrees.

[0037] 12: Testing: The product meets the product standard requirements.

[0038] 13: Filling: All filling equipment must be sterilized and qualified before filling. After filling, the product must be commercially sterilized and packaged for storage after passing the test.

[0039] Example 2 This embodiment provides a process for preparing pear paste using Laiyang Ci pear, and the specific steps are as follows: 1: Raw material selection: Mainly from the Laiyang Ci pear planting and production center, use fresh Laiyang Ci pears, which must be free of insect pests, rot, and agricultural residues that meet national food hygiene requirements.

[0040] 2: Raw material selection: select out those with insect pests, rotten fruits and impurities.

[0041] 3: Cleaning: Pour the selected Laiyang Ci pears into the fruit cleaning equipment, and use two steps of bubble cleaning followed by spray cleaning to clean the pears in all directions to ensure that they are clean.

[0042] 4: Crushing: Use a hammer-type stainless steel machine for crushing, and the particles are required to be 1.0CM.

[0043] 5: Color protection: Add color protection agent during the crushing process. The color protection agent is citric acid and the addition amount is 0.1%.

[0044] 6: Pressing: Use a spiral juicer for pressing, the mesh size is 0.1MM, and the pear residue is required to be in a cake shape.

[0045] 7: Ultrasonic extraction: Put the pear residue into the ultrasonic extraction tank, add 20% pure water, turn on the ultrasonic equipment, the temperature is 50 degrees, the time is 30 minutes, turn off the ultrasonic equipment, and extract the juice in the equipment.

[0046] 8: Filtration: Filter the squeezed juice and extracted juice through a vibrating screen (200 mesh filter) and pump them into a stainless steel tank with a stainless steel pump for storage.

[0047] 9: Boiling: Pump the pear juice in the stainless steel tank into the sandwich pot and heat it. Stop heating 30 minutes after boiling.

[0048] 10: Filtration: Filter through 300-mesh filter equipment and pump into storage tank for storage.

[0049] 11: Concentration: Use vacuum low-temperature concentration, the vacuum degree is 0.09 Pa, and the temperature is less than 75 degrees.

[0050] 12: Testing: The product meets the product standard requirements.

[0051] 13: Filling: All filling equipment must be sterilized and qualified before filling. After filling, the product must be commercially sterilized and packaged for storage after passing the test.

[0052] Example 3 This embodiment provides a process for preparing pear paste using Laiyang Ci pear. The specific steps are different from those of embodiment 1 in that an enzymatic hydrolysis step of the pear residue is added before ultrasonic extraction in step (4). The enzymatic hydrolysis of the pear residue is treated with cellulase and pectinase. The specific steps of enzymatic hydrolysis of the pear residue are as follows: add 20% of the weight of the pear residue to the pear residue with pure water, and then add cellulase and pectinase, the weight of the cellulase and pectinase being 0.1% and 0.1% of the weight of the material respectively; maintain the temperature at 30°C with continuous stirring; the enzymatic hydrolysis time is 1h, and then the temperature is raised to 80°C.

[0053] Example 4 This embodiment provides a process for preparing pear paste using Laiyang Ci pear. The specific steps are different from those of embodiment 2 in that an enzymatic hydrolysis step of the pear residue is added before ultrasonic extraction in step (4). The enzymatic hydrolysis of the pear residue is treated with cellulase and pectinase. The specific steps of enzymatic hydrolysis of the pear residue are as follows: add 20% of the weight of the pear residue to the pear residue with pure water, and then add cellulase and pectinase, the weight of the cellulase and pectinase being 2% and 3% of the weight of the material respectively; maintain the temperature at 50°C and stir continuously; the enzymatic hydrolysis time is 2h, and then the temperature is raised to 90°C.

[0054] Comparative Example 1 This comparative example provides a process for preparing pear paste using Laiyang Ci pear. The specific steps are different from those of Example 1 in that this comparative example lacks the step of ultrasonic extraction, that is, the pear residue obtained by squeezing in step (6) is directly boiled with pear juice.

[0055] Comparative Example 2 This comparative example provides a process for preparing pear paste using Laiyang Ci pear. The specific steps are different from those of Example 2 in that this comparative example lacks the step of ultrasonic extraction, i.e., the pear residue obtained by squeezing in step (6) is directly boiled with pear juice.

[0056] Experimental Example 1 The pear pastes prepared in the above Examples 1 and 2 and Comparative Examples 1 and 2 were tested, especially the content of protocatechuic acid in the pear pastes. The specific results are as follows:

Claims

1. Application of ultrasonic extraction in the production process of increasing the protocatechuic acid content in pear paste.

2. Application of ultrasonic extraction and enzymatic hydrolysis technology in the production process of increasing the protocatechuic acid content in pear paste.

3. A production process for increasing the protocatechuic acid content of pear paste, characterized in that: Including ultrasonic extraction and enzymatic hydrolysis process.

4. A production process for increasing the protocatechuic acid content of pear paste, characterized in that: The main steps include: (1) Crushing: Use a hammer-type stainless steel machine to crush the pears, and the particles should be 0.5-1.0CM; (2) Color protection: Add color protection agent during the crushing process, the addition amount is 0.05-0.1%; (3) Pressing: Use a spiral juicer for pressing, the mesh size is 0.1MM, and the pear residue is required to be in a cake shape; (4) Ultrasonic extraction: put the pear residue into the ultrasonic extraction tank, add 20% pure water by weight of the pear residue, turn on the ultrasonic equipment, set the temperature to 40-50 degrees, and extract the juice from the equipment for 30 minutes. (5) Filtration: Filter the squeezed juice obtained in step (3) and the extracted juice obtained in step (4) through a vibrating screen (200 mesh filter), and pump them into a stainless steel tank for storage using a stainless steel pump; (6) Boiling: Pump the pear juice in the stainless steel tank into the sandwich pot and heat it. Stop heating 30 minutes after boiling. (7) Filtration: Filtered by 300-mesh filter equipment and pumped into a storage tank for storage; (8) Concentration: vacuum low-temperature concentration is adopted, the vacuum degree is 0.09 Pa, and the temperature is less than 75 degrees; (9) Testing: The product meets the product standard requirements; (10) Filling: All filling equipment must be disinfected and qualified before filling; after filling, the product must be commercially sterilized and packaged for storage after passing the inspection.

5. The production process for increasing the protocatechuic acid content of pear paste according to claim 3, characterized in that: The method further includes a step of adding an enzymatic hydrolysis step to the pear residue before the ultrasonic extraction in step (4).

6. The production process for increasing the protocatechuic acid content of pear paste according to claim 4, characterized in that: The enzymatic hydrolysis of pear residue was carried out by using cellulase and pectinase.

7. The production process for increasing the protocatechuic acid content of pear paste according to claim 5, characterized in that: The specific steps of enzymatic hydrolysis of pear residue are as follows: adding 20% ​​pure water by weight of the pear residue to the pear residue, and then adding cellulase and pectinase, the weight of cellulase and pectinase are 0.1-2% and 0.1-3% of the weight of the material respectively; maintaining the temperature at 30-50°C and stirring continuously; the enzymatic hydrolysis time is 1-2h, and then the temperature is raised to 80-90°C.

8. The production process for increasing the protocatechuic acid content of pear paste according to claim 3, characterized in that: Enzymatic hydrolysis was performed simultaneously during the ultrasonic extraction process.

9. The production process for increasing the protocatechuic acid content of pear paste according to claim 7, characterized in that: The specific steps of performing enzymatic hydrolysis during ultrasonic extraction are as follows: put the pear residue into an ultrasonic extraction tank, add 20% pure water by weight of the pear residue, and add cellulase and pectinase at the same time, the weight of the cellulase and pectinase are 0.1-2% and 0.1-3% of the weight of the material respectively, and stir continuously, turn on the ultrasonic equipment at the same time, the temperature is 40-50 degrees, the time is 30-60 minutes, turn off the ultrasonic equipment, and extract the juice in the equipment.

10. The production process for increasing the protocatechuic acid content of pear paste according to claim 4, characterized in that: The color protecting agent added in the color protecting step is VC or citric acid.

11. The production process for increasing the protocatechuic acid content of pear paste according to claim 4, characterized in that: The pears selected in step (1) are Laiyang Ci pears.

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