Method for preparing starch from mung beans

Abstract

The invention discloses a method for preparing starch from mung beans. The method comprises the following steps: soaking the mung beans: soaking the mung beans with clean water; performing pulping treatment: performing pulping treatment on the soaked mung beans by using equipment to obtain mung bean milk; primary precipitation: adding the soaking water into the mung bean milk water, uniformly stirring and precipitating to obtain white fine powder; secondary treatment: dispersing the white fine powder by stirring with clear water, dropping out the secondarily precipitated slurry, and collecting to obtain fermentation seed water; repeatedly making: repeating the step 1 and the step 2, adding the fermentation seed water and the soaking water into the newly obtained mung bean milk water, and pouring out all the milk water to obtain white fine powder; the fourth step is repeated, the slurry water obtained after secondary precipitation falls out and is used as fermentation seed water in next preparation, and the secondary precipitate is mung bean starch; and drying treatment: performing vacuum drying on the mung bean starch. The method has the advantages that starch extraction rate is increased; starch separation and quality improvement are optimized; the starch quality is stabilized; secondary precipitation water can be recycled; the production process is simplified.

Description

Technical Field

[0001] The present invention relates to the technical field of starch production, and particularly to a method for producing starch from mung beans. Background Art

[0002] In modern industry and daily life, mung bean starch plays a key role in multiple fields due to its unique properties. In the food field, mung bean starch is often used to make traditional delicacies such as vermicelli and jelly. The products made from it have a smooth taste and good toughness, and are deeply loved by consumers. At the same time, in food processing, it can also be used as a thickener and stabilizer, which can effectively improve the texture and taste of food and extend the shelf life of food. In the pharmaceutical field, due to its good biocompatibility and stability, mung bean starch is widely used in the production of pharmaceutical preparations. It can be used as an excipient and disintegrant for tablets, etc., which helps the formation and release of drugs. In the chemical industry, mung bean starch can be used to manufacture adhesives, coatings and other products, providing a variety of raw material choices for industrial production.

[0003] However, there are many problems that cannot be ignored in the current traditional method for producing mung bean starch. In terms of starch extraction rate, traditional processes often cannot fully separate the starch in mung beans, resulting in a large amount of starch remaining in the mung bean residue and being wasted, making the extraction rate generally low. This not only causes waste of resources but also increases production costs. In terms of quality stability, traditional methods are greatly affected by environmental factors and operation processes. There are significant differences in purity, particle size, gelatinization characteristics, etc. of mung bean starch produced in different batches, making it difficult to meet the requirements of industries with high demands for product quality consistency. For example, in food processing, unstable starch quality will lead to fluctuations in product taste and quality, affecting the consumer experience. From the production process, traditional production methods have complex steps, requiring multiple operations such as soaking, grinding, filtering, and precipitation, and strict control of time and conditions is required for each link. The production efficiency is low, and it is difficult to achieve large-scale industrial production. In summary, in order to better meet the market demand for mung bean starch, it is urgent to develop an efficient, stable and simple method for producing starch from mung beans. Summary of the Invention

[0004] To solve the above problems, especially the deficiencies of the existing technology, the present invention provides a method for producing starch from mung beans that can solve the above problems.

[0005] To achieve the above object, the present invention adopts the following technical means:

[0006] A method for producing starch from mung beans, comprising the following steps:

[0007] Step 1: Soaking mung beans:

[0008] Select high-quality and plump mung beans, soak them in 3-5 times of clean water until the mung beans swell to 2.3-2.5 times their original size, and then end the soaking;

[0009] Step Two: Pulping treatment:

[0010] Use a pulp and residue separation pulping device to pulp the soaked mung beans, and separate the mung bean residue repeatedly for multiple times to obtain mung bean pulp water;

[0011] Step Three: Primary precipitation:

[0012] Add all the soaking water of the soaked mung beans to the mung bean pulp water, stir evenly, and then carry out precipitation. The temperature of the precipitation environment is 28-30°C, and the precipitation time is 2-3 hours. When the surface of the pulp water is clear, pour out all the pulp water to obtain white fine powder;

[0013] Step Four: Secondary precipitation and purification:

[0014] Stir the white starch in Step Three with 1.5 times the amount of clear water of the mung beans, then filter and precipitate through a 200-mesh sieve for 7-9 hours, pour out and collect the separated yellow pulp water to obtain fermentation starter water;

[0015] Step Five: Repeat the production:

[0016] Repeat Step One and Step Two, then add the fermentation starter water and all the soaking water of the soaked mung beans to the newly obtained mung bean pulp water, stir evenly, and then carry out precipitation. The temperature of the precipitation environment is 10-35°C, and the precipitation time is 2-3 hours. When the surface of the pulp water is clear, pour out all the pulp water to obtain white fine powder; then repeat Step Four, pour out the pulp water after secondary precipitation and use it as fermentation starter water for the next production. The secondary precipitate in Step Four is the moisture-retaining fresh mung bean starch;

[0017] Step Six: Drying treatment:

[0018] Carry out drying treatment on the moisture-retaining fresh mung bean starch by natural drying to obtain dry mung bean starch.

[0019] A further solution of the present invention is that in Step One, a screening method combining air separation and water separation is used to screen mung beans.

[0020] A further solution of the present invention is that in Step One, the clean water is drinking water that meets the national hygienic standards for domestic drinking water.

[0021] A further solution of the present invention is that in Step One, the mung beans are stirred once every half hour during the soaking process.

[0022] A further solution of the present invention is that in Step Two, the number of times of repeatedly separating the mung bean residue is 2-5 times.

[0023] In a further embodiment of the present invention, in step three, the stirring is carried out at a low speed of 50 - 80 revolutions per minute for 15 - 20 minutes.

[0024] In a further embodiment of the present invention, in step four, the fermented starter water is left for 24 hours and then used for the repeated production in step five.

[0025] In a further embodiment of the present invention, in step five, the amount of the fermented starter water is determined according to the temperature. The specific data relationship is as follows:

[0026] When the temperature of the precipitation environment is 35°C, the amount of the fermented starter water used is 20% of the collected amount;

[0027] When the temperature of the precipitation environment is 30°C, the amount of the fermented starter water used is 30% of the collected amount;

[0028] When the temperature of the precipitation environment is 20°C, the amount of the fermented starter water used is 50% of the collected amount;

[0029] When the temperature of the precipitation environment is 10°C, the amount of the fermented starter water used is 100% of the collected amount.

[0030] In a further embodiment of the present invention, in step five, the moisture - retaining fresh mung bean starch is used to make jelly. The specific production method is as follows:

[0031] 1 jin of moisture - retaining fresh mung bean starch is mixed with 1 jin of clean water to form a starch slurry. 3.5 jin of clean water is put into a pot and brought to a boil. The prepared starch slurry is stirred again until it is dispersed and then quickly poured into the pot and continuously stirred. The temperature in the pot is controlled at 85°C. When the starch slurry changes from white to green - yellow, becomes crystal - clear and sticky in a lump, it is taken out of the pot and put into a container of the required specification to cool.

[0032] In a further embodiment of the present invention, the moisture content of the moisture - retaining fresh mung bean starch is 40%.

[0033] Advantages of the present invention:

[0034] 1. The present invention improves the starch extraction rate. By adopting a screening method combining air - separation and water - separation, impurities in mung beans can be effectively removed, ensuring excellent quality of mung beans for making starch, and providing guarantee for subsequent high - efficiency starch extraction. In the grinding and pulping process, the mung bean residue is separated repeatedly for multiple times, greatly improving the separation degree of starch from the mung bean residue, significantly increasing the starch extraction rate, effectively reducing starch waste, and lowering production costs.

[0035] 2. The present invention optimizes starch separation and quality improvement. During the production process, mung bean soaking water and fermented starter water are innovatively added to the starch slurry. These two kinds of water can undergo a fermentation reaction in the starch slurry, prompting the fine powder and yellow powder to achieve nearly 100% self-separation. This efficient separation process not only improves the purity of the starch but also significantly enhances the gluten strength of the starch products, greatly improving the starch quality.

[0036] 3. The present invention stabilizes the starch quality. By precisely controlling the precipitation temperature at 28 - 30 °C, the precipitation time at 2 - 3 hours for the first precipitation and 7 - 9 hours for the second precipitation, and the stirring speed at 50 - 80 revolutions per minute for the first precipitation, and adopting an alternating clockwise and counterclockwise stirring method with a stirring time of 3 - 5 minutes each time when dispersing the white fine powder, etc., a series of parameters make the starch more fully and evenly precipitated and separated during the precipitation and separation processes, effectively reducing the differences in purity, particle size, gelatinization characteristics, etc. between different batches of products, and ensuring the stability of the starch quality.

[0037] 4. The present invention has the advantage of recycling the secondary precipitation water. The recycling of the secondary precipitation water is a major highlight of the present invention. For example, the secondary precipitation water generated in this production (No. 1) can be used for the next production (No. 2), and the secondary precipitation water generated by No. 2 is used for No. 3, and so on. As the number of recycling times increases, the beneficial microorganisms and fermentation products accumulated in the precipitation water increase, the self-separation effect of the fine powder and yellow powder becomes better and better, and the starch quality also continuously improves. While reducing water resource waste, it reduces production costs and realizes the efficient utilization of resources and sustainable development.

[0038] 5. The present invention simplifies the production process. Using the fermented starter water for repeated production optimizes the overall production process. During the repeated production process, new mung bean slurry water is added to the fermented starter water and soaking water and then undergoes precipitation and other operations, reducing some unnecessary intermediate links and complex treatment steps, making the production process more concise and efficient, facilitating large-scale industrial production, improving production efficiency, and reducing labor costs and time costs. Specific Embodiments

[0039] The technical solutions of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0040] Example 1

[0041] A method for making starch from mung beans, comprising the following steps:

[0042] Step 1. Mung bean soaking:

[0043] Select high-quality and plump mung beans, and screen the mung beans by a screening method combining winnowing and water selection. Soak the mung beans in 3 - 5 times of clean water that meets the national hygienic standard for domestic drinking water. Stir the mung beans every half hour during the soaking process until the mung beans are soaked and swollen to 2.3 - 2.5 times their original size, then end the soaking.

[0044] Step Two: Pulping treatment:

[0045] Use a pulp residue separation pulping equipment to pulp the soaked mung beans, and separate the mung bean residue repeatedly for 2 - 5 times to obtain mung bean pulp water.

[0046] Step Three: Primary precipitation:

[0047] Add all the soaking water of the soaked mung beans to the mung bean pulp water, stir at a low speed of 50 - 80 revolutions per minute for 15 - 20 minutes. After stirring evenly, carry out precipitation. The temperature of the precipitation environment is 28 - 30 °C, and the precipitation time is 2 - 3 hours. When the surface of the pulp water is clear, pour out all the pulp water to obtain white fine powder.

[0048] Step Four: Secondary precipitation and purification:

[0049] Stir the white starch in Step Three with 1.5 times the amount of clear water of the mung beans. When stirring, use an alternating stirring method of clockwise and counterclockwise, and each stirring time is 3 - 5 minutes. Then filter and precipitate with a 200 - mesh sieve for 7 - 9 hours, pour out and collect the separated yellow pulp water to obtain fermented seed water. The fermented seed water is left for 24 hours and then used for subsequent repeated production.

[0050] Step Five: Repeated production:

[0051] Repeat Step 1 and Step 2, then add the fermented starter water and all the soaking water of the soaked mung beans to the newly obtained mung bean milk water. After stirring evenly, conduct precipitation. The temperature of the precipitation environment is 10 - 35°C, and the precipitation time is 2 - 3 hours. The dosage of the fermented starter water is determined according to the temperature. The specific data relationship is as follows: when the temperature of the precipitation environment is 35°C, the dosage of the fermented starter water is 20% of the collected amount; when the temperature of the precipitation environment is 30°C, the dosage of the fermented starter water is 30% of the collected amount; when the temperature of the precipitation environment is 20°C, the dosage of the fermented starter water is 50% of the collected amount; when the temperature of the precipitation environment is 10°C, the dosage of the fermented starter water is 100% of the collected amount. When the surface of the milk water is clear, pour out all the milk water to obtain white fine powder; then repeat Step 4, pour out the milk water after secondary precipitation and use it as fermented starter water for the next production. The secondary precipitate in Step 4 is the moisture-retaining fresh mung bean starch with a moisture content of 40%. The specific method for making jelly with this moisture-retaining fresh mung bean starch is as follows: Mix 1 catty of moisture-retaining fresh mung bean starch with 1 catty of clean water to form a starch slurry. Bring 3.5 catties of clean water to a boil in a pot, stir the prepared starch slurry again to disperse it and quickly pour it into the pot and keep stirring. Control the temperature in the pot at 85°C. As the starch slurry changes from white to greenish-yellow, becomes crystal clear and agglomerates into a ball, remove it from the pot and put it into a container of the required specification to cool down.

[0052] Step 6. Drying treatment:

[0053] Carry out drying treatment on the moisture-retaining fresh mung bean starch by natural sun drying to obtain dried mung bean starch.

[0054] Example 2:

[0055] A method for making starch from mung beans, comprising the following steps:

[0056] Step 1. Mung bean soaking: Select 5 kilograms of mung beans. First, use a winnowing machine to blow away impurities such as dust and shriveled beans, then put them into clean water and fish out the floating objects to complete water selection. Place the selected mung beans in a large container and soak them with 20 liters of tap water that meets the national hygienic standard for domestic drinking water. Every half hour, gently stir with a long-handled stirrer. After 6 hours, the mung beans swell to 2.4 times their original volume, and the soaking ends.

[0057] Step 2. Pulping treatment: Start a professional pulp residue separation pulping machine, pour the soaked mung beans into it, and turn on the machine for grinding. Put the initially separated mung bean residue into the pulping machine again and repeat the separation operation 3 times, and collect all the mung bean milk water.

[0058] Step 3: Initial precipitation: Pour all 20 liters of water used to soak mung beans into the collected mung bean slurry, and stir with an electric stirrer at 65 rpm for 16 minutes. Then, transfer the mixed slurry to a sedimentation tank, maintain the ambient temperature at 28°C, and precipitate for 2 hours and 20 minutes. When the surface of the slurry is clear, carefully pour off the upper slurry, leaving white powder at the bottom of the tank.

[0059] Step 4: Secondary precipitation and purification: Take 7.5 liters of clean water and slowly pour it into the white powder. Stir it clockwise for 3 minutes, then counterclockwise for 3 minutes to fully disperse the powder. Then, filter it with a 200-mesh filter and place the filtrate in a sedimentation bucket for 8 hours. After that, pour out the upper layer of yellow slurry water and collect it to obtain the fermentation seed water, which is sealed and placed for 24 hours.

[0060] Step 5, repeat the production: re-select 5 kg of mung beans, repeat steps 1 and 2 to get new mung bean slurry. At this time, the ambient temperature is 32°C. Take 25% of the fermentation water collected last time, add it to the new slurry together with the soaking water this time, and stir evenly. Precipitate at 32°C for 2 hours and 10 minutes, pour off the supernatant to get white powder. Repeat step 4, retain the slurry after the second precipitation, and the secondary precipitate is moisturizing fresh mung bean starch with a water content of about 40%.

[0061] Step 6. Drying: Spread the moisturizing fresh mung bean starch evenly on a bamboo plate and place it in a well-ventilated and sunny place to dry. After about 3 days, you will get the dried mung bean starch.

[0062] Embodiment 3:

[0063] A method for preparing starch from mung beans comprises the following steps:

[0064] Step 1: Soaking mung beans: Weigh 8 kg of mung beans, remove impurities through air and water selection. Put the selected mung beans into a large vat and add 32 liters of purified domestic water to soak. Stir with a wooden stick every half an hour. After 7 hours, the mung beans will expand to 2.3 times their original volume, and then stop soaking.

[0065] Step 2: Refining: Use large-scale pulp-residue separation and refining equipment to process the soaked mung beans. The mung bean residue separated for the first time is repeatedly put into the refining equipment for 4 separations, and the mung bean pulp water is obtained.

[0066] Step 3: Initial precipitation: Pour all 32 liters of water used to soak mung beans into the mung bean milk, and stir with a stirring paddle at 70 rpm for 18 minutes. Then, pour the mixture into a large precipitation tank, maintain the temperature at 29°C, and precipitate for 2 hours and 30 minutes. When the surface water is clear, scoop off the upper layer of water to obtain white fine powder.

[0067] Step 4. Secondary precipitation and purification: Prepare 12 liters of clean water, pour it into the white fine powder, and stir alternately clockwise and counterclockwise for 4 minutes each time. Then, filter it through a 200-mesh filter screen, put the filtrate into the precipitation tank, and precipitate for 7 hours and 30 minutes. Pour out and collect the upper yellow slurry water to obtain the fermented seed water, and store it for 24 hours.

[0068] Step 5. Repeat the production: Select 8 kg of mung beans again, operate according to Steps 1 and 2 to obtain new mung bean slurry water. The current ambient temperature is 18°C. Take 60% of the fermented seed water collected last time, add it to the new slurry water together with the current soaking water, and stir evenly. Precipitate for 2 hours and 20 minutes at 18°C, pour out the upper clear liquid to obtain the white fine powder. Repeat Step 4. The slurry water after secondary precipitation is reserved for the next use, and the secondary precipitate is the moisture-retaining fresh mung bean starch.

[0069] Step 6. Drying treatment: Spread the moisture-retaining fresh mung bean starch on a clean cloth and place it in a dry and ventilated place to dry for about 4 days to make dry mung bean starch.

[0070] Example 4:

[0071] Step 1: Mung bean soaking: Take 3 kg of mung beans, after winnowing and water selection, put them into a plastic bucket, and add 12 liters of standard mineral water for soaking. Stir with a plastic stirring rod every half hour. After 5 hours and 30 minutes, the mung beans swell to 2.5 times their original size, and the soaking ends.

[0072] Step 2. Pulping treatment: Use a small household pulp residue separation pulping machine to process the soaked mung beans. Repeat the separation of the initially separated mung bean residue 2 times, and collect the mung bean slurry water.

[0073] Step 3. Primary precipitation: Pour the 12 liters of water used to soak the mung beans into the mung bean slurry water, and stir with a manual stirrer at a speed of 55 revolutions per minute for 15 minutes. Then, transfer the mixed slurry water to a glass container, precipitate at 30°C for 2 hours. When the surface of the slurry water is clear, pour out the upper slurry water and leave the white fine powder.

[0074] Step 4. Secondary precipitation and purification: Measure 4.5 liters of clean water, pour it into the white fine powder, stir clockwise and counterclockwise for 3 minutes each to disperse it. Filter it through a 200-mesh filter screen, put the filtrate into a glass precipitation bottle, and precipitate for 8 hours and 30 minutes. Pour out and collect the upper yellow slurry water to obtain the fermented seed water, and let it stand for 24 hours.

[0075] Step 5. Repeat the production: Weigh 3 kg of mung beans again, repeat Steps 1 and 2 to obtain new mung bean slurry water. At this time, the ambient temperature is 22°C. Take 45% of the fermented seed water collected last time, add it to the new slurry water together with the current soaking water, and stir evenly. Precipitate for 2 hours and 10 minutes at 22°C, pour out the upper clear liquid to obtain the white fine powder. Repeat Step 4. The slurry water after secondary precipitation is retained, and the secondary precipitate is the moisture-retaining fresh mung bean starch.

[0076] Step 6, Drying treatment: Spread the moisture-retaining fresh mung bean starch thinly on a plate and place it on a sunny windowsill to dry for about two and a half days to obtain dry mung bean starch.

[0077] Verification method

[0078] Experimental design

[0079] Group setting: Divide the experiment into two groups, namely the experimental group and the control group. The experimental group uses the method for making starch from mung beans proposed in the present invention, and the control group uses the traditional method for making mung bean starch. Conduct 10 parallel experiments for each group to reduce experimental errors and ensure the accuracy and reliability of the experimental results.

[0080] The method for making mung bean starch in the control group is as follows:

[0081] Mung bean selection and cleaning

[0082] Mung bean selection: Select mung beans with plump grains, no insect damage, and no mildew. Try to choose new mung beans of the current year to ensure the starch yield and quality.

[0083] Cleaning: Put the selected mung beans into clean water, gently stir with hands, and rinse off the dust and impurities on the surface of the mung beans. Soak in water for 1 - 2 hours to make the mung beans fully absorb water and swell, facilitating subsequent peeling operations.

[0084] Peeling and grinding

[0085] Peeling: Take out the soaked mung beans, drain the water, put them into a blender, add an appropriate amount of water, just enough to cover the mung beans. Start the blender and stir the mung beans into a mixture of mung bean paste and bean skins. Then pour the mixture into a sieve and rinse with clean water to separate the bean skins from the mung bean paste. Scoop out the bean skins and let them dry for other uses.

[0086] Grinding: Pour the mung bean paste into a stone mill or grinder for grinding. When grinding, add an appropriate amount of clean water according to needs to keep the mung bean paste at a certain consistency, facilitating grinding and subsequent filtration. Grind until the mung bean paste is fine and uniform without obvious granularity.

[0087] Filtration and precipitation

[0088] Filtration: Filter the ground mung bean paste with multiple layers of gauze or a filter screen to remove the bean dregs. To improve the filtration effect, pour the mung bean paste into the filter screen in multiple batches, with an appropriate amount poured each time, and let the mung bean paste filter naturally. If the filtration speed is slow, gently squeeze the filter screen to make the mung bean paste fully filtered, but be careful not to exert too much force to avoid squeezing the bean dregs into the filtrate.

[0089] Precipitation: Pour the filtered mung bean milk into a clean container and let it stand for 6 - 8 hours. During the precipitation process, the mung bean starch will gradually settle to the bottom of the container, and the upper layer is the clear liquid. The precipitation time should not be too long, otherwise the starch may ferment and deteriorate.

[0090] Drying

[0091] Drying: After the precipitation is completed, carefully pour out the upper clear liquid, leaving the starch block at the bottom. Take out the starch block and let it dry in a well - ventilated and sunny place, or put it in a drying oven and dry it at a temperature of 40 - 50 °C. During the drying process, pay attention to frequently turning the starch block to make it dry evenly and avoid caking.

[0092] Raw material control: In each experiment, select high - quality and plump mung beans of the same variety with a mass of 1000 g as raw materials. At the same time, ensure that the experimental group and the control group are consistent in terms of experimental environment, equipment and reagents used, etc. The only variable is the starch production method.

[0093] Data analysis

[0094] Data sorting

[0095] Experimental group: In 10 parallel experiments, the starch extraction rate data are 84%, 86%, 85%, 87%, 85%, 88%, 86%, 84%, 87%, 85% respectively; the purity data are 92%, 94%, 93%, 95%, 93%, 96%, 94%, 92%, 95%, 93% respectively; the production time data are 22 h, 21 h, 23 h, 22 h, 21 h, 23 h, 22 h, 22 h, 23 h, 21 h respectively.

[0096] Control group: In 10 parallel experiments, the starch extraction rate data are 70%, 72%, 71%, 73%, 72%, 74%, 71%, 70%, 73%, 72% respectively; the purity data are 80%, 82%, 81%, 83%, 82%, 84%, 81%, 80%, 83%, 82% respectively; the production time data are 32 h, 33 h, 31 h, 32 h, 33 h, 31 h, 32 h, 33 h, 31 h, 32 h respectively.

[0097] Calculation of statistics

[0098] Experimental group:

[0099] Average starch extraction rate: (84 + 86 + 85 + 87 + 85 + 88 + 86 + 84 + 87 + 85) ÷ 10 = 85.7%

[0100] Average purity: (92 + 94 + 93 + 95 + 93 + 96 + 94 + 92 + 95 + 93) ÷ 10 = 93.7%

[0101] Average production time: (22 + 21 + 23 + 22 + 21 + 23 + 22 + 22 + 23 + 21) ÷ 10 = 22 h

[0102] Standard deviation of starch extraction rate: approximately 1.16

[0103] Standard deviation of purity: approximately 1.34

[0104] Standard deviation of production time: approximately 0.82

[0105] Control group:

[0106] Average starch extraction rate: (70 + 72 + 71 + 73 + 72 + 74 + 71 + 70 + 73 + 72) ÷ 10 = 72%

[0107] Average purity: (80 + 82 + 81 + 83 + 82 + 84 + 81 + 80 + 83 + 82) ÷ 10 = 82%

[0108] Average production time: (32 + 33 + 31 + 32 + 33 + 31 + 32 + 33 + 31 + 32) ÷ 10 = 32 h

[0109] Standard deviation of starch extraction rate: approximately 1.14

[0110] Standard deviation of purity: approximately 1.14

[0111] Standard deviation of production time: approximately 0.82

[0112] Comparison result: After multiple parallel experiments and data analysis, the experimental group is significantly higher than the control group in terms of starch extraction rate and purity, and the production time is significantly shorter than that of the control group. This fully demonstrates that the mung bean starch-making method of the present invention has significant superiority over the traditional method and can effectively improve production efficiency and product quality.

[0113] The examples given in the present invention are not intended to limit the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here, and the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A method for producing starch from mung beans, characterized in that: The following steps are involved: Step 1: Soak mung beans: Select high-quality, plump mung beans and soak them in 3-5 times of clean water until the mung beans swell to 2.3-2.5 times. Step 2: Refining: The soaked mung beans are ground using pulp-residue separation and grinding equipment, and the separated mung bean residue is repeatedly separated multiple times to obtain mung bean pulp water; Step 3: Initial precipitation: Add all the soaking water of mung beans into the mung bean slurry, stir evenly and then precipitate. The temperature of the precipitation environment is 28-30°C and the precipitation time is 2-3 hours. When the surface of the slurry is clear, pour out all the slurry to obtain white fine powder. Step 4: Secondary precipitation and purification: Use 1.5 times the amount of clean water as mung beans to disperse the white starch in step 3, and then filter and precipitate it with a 200-mesh sieve for 7-9 hours, pour out the separated yellow slurry water and collect it to obtain the fermentation seed water; Step 5: Repeat the process: Repeat steps 1 and 2, then add the fermentation seed water and all the soaking water of mung beans into the newly obtained mung bean slurry, stir evenly and then precipitate, the temperature of the precipitation environment is 10-35°C, the precipitation time is 2-3 hours, when the slurry surface is clear, pour out all the slurry to obtain white refined powder; then repeat step 4, drop out the slurry after secondary precipitation and use it as fermentation seed water in the next production, the secondary precipitation in step 4 is the moisture-keeping fresh mung bean starch; Step 6: Drying: The moisture retaining fresh mung bean starch is dried by natural air-drying to obtain mung bean dry starch.

2. The method for producing starch from mung beans according to claim 1, characterized in that: In the step 1, a screening method combining air selection and water selection is used to screen mung beans.

3. The method for producing starch from mung beans according to claim 1, characterized in that: In step 1, the clean water is drinking water that meets the national drinking water hygiene standards.

4. The method for producing starch from mung beans according to claim 1, characterized in that: In the step 1, the mung beans are stirred every half an hour during the soaking process.

5. The method for producing starch from mung beans according to claim 1, characterized in that: In the step 2, the mung bean dregs are separated repeatedly 2-5 times.

6. The method for producing starch from mung beans according to claim 1, characterized in that: In the step 3, stirring is performed at a low speed of 50-80 rpm for 15-20 minutes.

7. The method for producing starch from mung beans according to claim 1, characterized in that: In step 4, the fermented seed water is placed for 24 hours before being used for repeated production in step 5.

8. The method for producing starch from mung beans according to claim 1, characterized in that: In step 5, the amount of fermentation water is determined according to the temperature, and the specific data relationship is: When the temperature of the sedimentation environment is 35°C, the amount of fermentation water used is 20% of the collected amount; When the temperature of the sedimentation environment is 30°C, the amount of fermentation water used is 30% of the collected amount; When the temperature of the sedimentation environment is 20°C, the amount of fermentation water used is 50% of the collected amount; When the temperature of the precipitation environment is 10°C, the amount of fermentation seed water used is 100% of the collected amount.

9. The method for producing starch from mung beans according to claim 1, characterized in that: In the step 5, the moisturizing fresh mung bean starch is used to make jelly, and the specific production method is as follows: Add 1 pound of moisturizing fresh mung bean starch to 1 pound of clean water to make starch slurry. Bring 3.5 pounds of clean water to a boil. Stir the prepared starch slurry again and quickly pour it into the pot and stir continuously. The temperature in the pot should be controlled at 85°C. As the starch slurry changes from white to green-yellow, becomes crystal clear and sticks together, remove from the pot and put it into a container of the required specifications to cool.

10. The method for producing starch from mung beans according to claim 9, characterized in that: The moisture content of the fresh mung bean starch with moisture retention is 40%.