Special base material formula for sesame pelletized seeds convenient to form and coat

Abstract

The invention discloses a special base material formula for sesame pelletized seeds convenient to form and coat, and belongs to the technical field of agricultural seed treatment. The base material formula comprises the following components in parts by weight: 20-35 parts of modified starch, 5-12 parts of sodium carboxymethyl cellulose, 10-20 parts of vermiculite powder, 15-25 parts of humus soil, 8-15 parts of bentonite, 2-5 parts of polyethylene glycol, 1-3 parts of trehalose and 25-40 parts of water. The preparation method comprises the four steps of raw material pretreatment, dry material mixing, wet material preparation and curing treatment. The base material disclosed by the invention has excellent forming and coating properties, the forming rate can reach 95% or above, and the coating uniformity is high; meanwhile, the air permeability and the water-retaining property are coordinated, and the germination rate of sesame seeds can be increased to 90% or above; the components are environment-friendly, and the preparation method is simple and controllable, is suitable for industrial production and has wide popularization and application prospects.

Description

Technical Field

[0001] This invention belongs to the field of agricultural seed treatment technology, specifically relating to a special base material formula for sesame seed pellets that is easy to form and coat. Background Technology

[0002] Sesame seeds are small, leading to uneven sowing, susceptibility to environmental stresses (such as drought and pests), and low germination rates when sown directly. Granulation is an effective way to solve these problems. By coating the seeds with a substrate to form pellets, the seed volume can be increased and sowing performance improved. At the same time, nutrients and pesticides can be added to the substrate to ensure seed germination.

[0003] Existing sesame seed pellet substrates have several shortcomings: First, they have poor forming performance, easily cracking and falling off during the coating process, and the pellet strength is insufficient, making them unsuitable for mechanized sowing. Second, the substrate's air permeability and water retention are unbalanced; excessive water retention can lead to seed mold, while excessive air permeability cannot meet the water requirements for seed germination. Third, the substrate has poor adhesion to the seeds, resulting in uneven coating and affecting the release and absorption of subsequent nutrients. Fourth, some substrates use chemically synthesized components, which can easily pollute the soil environment and may affect the safety of seed germination.

[0004] Therefore, developing a pelleted seed substrate with good formability, uniform coating, balanced air permeability and water retention, environmental friendliness, and the ability to ensure the germination vitality of sesame seeds has become an urgent technical problem to be solved in current agricultural production. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a special substrate formula for sesame seed pellets that is easy to form and coat, aiming to solve the problems of poor forming, uneven coating, imbalance between air permeability and water retention, and environmental unfriendliness of existing substrates, thereby improving the processing quality and sowing effect of sesame seed pellets.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a special base material formula for sesame seed pellets that is easy to form and coat, comprising the following components by weight: 20-35 parts modified starch, 5-12 parts sodium carboxymethyl cellulose, 10-20 parts vermiculite powder, 15-25 parts humus, 8-15 parts bentonite, 2-5 parts polyethylene glycol, 1-3 parts trehalose, and 25-40 parts water.

[0007] Furthermore, the modified starch is hydroxypropyl starch phosphate with a degree of substitution of 0.05-0.12, which is prepared by reacting starch with propylene oxide and a phosphorylation reagent, and has good water solubility, adhesion and molding stability.

[0008] Furthermore, the vermiculite powder has a particle size of 100-200 mesh. After being dried at 105-110℃ for 2-3 hours, the air permeability and water retention of the base material can be improved, while the structural strength of the pellets can be enhanced.

[0009] Furthermore, the humus soil is subjected to sieving (100 mesh) and sterilization (121℃ high-pressure steam sterilization for 30 minutes) to remove impurities and harmful microorganisms, ensuring the safety of the seed germination environment.

[0010] Furthermore, the base material formula can be supplemented with 0.5-2 parts of plant growth regulators (such as gibberellin) or 1-3 parts of biological fungicides (such as Bacillus subtilis) as needed to further enhance seed germination rate and stress resistance.

[0011] This invention also provides a method for preparing the above-mentioned sesame seed pelleting special substrate, comprising the following steps:

[0012] Step 1: Raw material pretreatment: Place vermiculite powder in an oven at 105-110℃ and dry for 2-3 hours, then cool to room temperature for later use; humus soil is sieved through a 100-mesh sieve to remove large impurities, then sterilized by high-pressure steam at 121℃ for 30 minutes, and cooled for later use.

[0013] Step 2: Dry material mixing: Weigh the modified starch, sodium carboxymethyl cellulose, pretreated vermiculite powder, humus, and bentonite according to the weight parts, place them in a mixer, and mix at a speed of 150-200 r / min for 15-20 min to obtain a uniform dry material mixture.

[0014] Step 3: Preparation of wet material: Weigh out polyethylene glycol and trehalose by weight, add them to water, and stir until completely dissolved to obtain a mixed aqueous solution; slowly add the mixed aqueous solution to the dry material mixture while stirring at a speed of 250-300 r / min for 20-30 min to obtain a uniform wet base material;

[0015] Step 4: Curing treatment: Place the wet substrate in a curing device and cure it at 60-70℃ for 15-20 minutes. After curing, cool it to room temperature to obtain a special substrate for sesame seed pellets that is easy to shape and coat.

[0016] The present invention also provides the application of the above-mentioned special base material in the preparation of sesame seed pellets. The specific application method is as follows: sesame seeds and special base material are placed in a pelleting device at a weight ratio of 1:3-1:5, and coated and shaped under the conditions of rotation speed of 50-80 r / min and temperature of 25-30℃. After shaping, the pellets are dried at a low temperature of 40-50℃ until the moisture content of the pellets is 8-12%, thus obtaining sesame seed pellets.

[0017] Compared with the prior art, the present invention provides a special base material formula for sesame seed pelleting that is easy to form and coat, and has the following beneficial effects:

[0018] 1. This invention uses modified starch and sodium carboxymethyl cellulose as a binder system, which works synergistically with the thickening and binding effect of bentonite to give the base material good adhesion and molding stability. It is not easy to crack or fall off during the coating process, and the pellet forming rate can reach more than 95%. Moreover, the coating uniformity is high, and it can form a continuous and dense coating layer to meet the needs of mechanized sowing.

[0019] 2. This invention utilizes the reasonable ratio of vermiculite powder and humus to improve the air permeability of the substrate by leveraging the porous structure of vermiculite powder, while simultaneously locking in moisture through the high water retention capacity of humus. This achieves an optimal balance between the air permeability and water retention of the substrate, preventing seeds from becoming moldy due to excessive moisture and continuously providing moisture for seed germination, thereby increasing the seed germination rate to over 90%.

[0020] 3. All components used in this invention are natural or environmentally friendly materials, without any chemically synthesized harmful substances. The humus soil can also improve soil fertility and will not pollute the soil environment. At the same time, the humus soil has been sterilized to remove harmful microorganisms, ensuring the safety of the seed germination environment and improving the seedling survival rate.

[0021] 4. The base material preparation method of the present invention has simple steps, and the process parameters are easy to control. It is suitable for large-scale industrial production, and the preparation process has low energy consumption and low cost, which is conducive to its promotion and application.

[0022] 5. The base material formula of the present invention can be supplemented with functional ingredients such as plant growth regulators and biological fungicides according to actual needs, which can further enhance the stress resistance and germination vitality of sesame seeds and adapt to the sowing needs under different environmental conditions. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1

[0025] A special base material formula for sesame seed pellets that is easy to form and coat, comprising, by weight: 25 parts of hydroxypropyl starch phosphate (degree of substitution 0.08), 8 parts of sodium carboxymethyl cellulose, 15 parts of vermiculite powder (150 mesh, dried at 108℃ for 2.5h), 20 parts of humus soil (100 mesh sieve, sterilized by high-pressure steam at 121℃ for 30min), 12 parts of bentonite, 3 parts of polyethylene glycol, 2 parts of trehalose, and 32 parts of water.

[0026] Preparation method:

[0027] Step 1: Raw material pretreatment: Place vermiculite powder in a 108℃ oven and dry for 2.5 hours, then cool to room temperature for later use; humus soil is sieved through a 100-mesh sieve to remove large impurities, then sterilized by high-pressure steam at 121℃ for 30 minutes, and cooled for later use.

[0028] Step 2: Dry material mixing: Weigh out the hydroxypropyl starch phosphate, sodium carboxymethyl cellulose, pretreated vermiculite powder, humus, and bentonite according to the above weight proportions, place them in a mixer, and mix at a speed of 180 r / min for 18 min to obtain a dry material mixture;

[0029] Step 3, Preparation of wet material: Weigh polyethylene glycol and trehalose, add them to water, and stir until completely dissolved to obtain a mixed aqueous solution; slowly add the mixed aqueous solution to the dry material mixture while stirring, with a stirring speed of 280 r / min and a stirring time of 25 min to obtain the wet base material;

[0030] Step 4, Curing treatment: Place the wet base material in a curing device and cure it at 65°C for 18 minutes. Then cool it to room temperature to obtain the special base material.

[0031] Application: Sesame seeds and special base material are placed in a pelleting equipment at a weight ratio of 1:4. The mixture is coated and shaped at a speed of 65 r / min and a temperature of 28℃. After shaping, the pellets are dried at a low temperature of 45℃ until the moisture content of the pellets is 10%, thus obtaining pelletized sesame seeds.

[0032] Example 2

[0033] A special base material formula for sesame seed pellets that is easy to form and coat, comprising, by weight: 20 parts of hydroxypropyl starch phosphate (degree of substitution 0.05), 5 parts of sodium carboxymethyl cellulose, 10 parts of vermiculite powder (100 mesh, dried at 105℃ for 2h), 15 parts of humus soil (100 mesh sieve, sterilized by high pressure steam at 121℃ for 30min), 8 parts of bentonite, 2 parts of polyethylene glycol, 1 part of trehalose, and 25 parts of water.

[0034] Preparation method:

[0035] Step 1: Raw material pretreatment: Place vermiculite powder in a 105℃ oven and dry for 2 hours, then cool to room temperature for later use; sieve the humus soil through a 100-mesh screen to remove large impurities, then sterilize it with high-pressure steam at 121℃ for 30 minutes, and cool it for later use.

[0036] Step 2: Dry material mixing: Weigh each dry material component according to the above weight proportions, place them in a mixer, and mix at a speed of 150 r / min for 15 min to obtain a dry material mixture;

[0037] Step 3, Preparation of wet material: Weigh polyethylene glycol and trehalose, add them to water to dissolve, and obtain a mixed aqueous solution; slowly add the mixed aqueous solution to the dry material mixture while stirring, with a stirring speed of 250 r / min and a stirring time of 20 min, to obtain the wet base material;

[0038] Step 4: Curing treatment: Curing the wet base material at 60℃ for 15 minutes, then cooling to room temperature to obtain the special base material.

[0039] Application: Sesame seeds and special base material are placed in a pelleting device at a weight ratio of 1:3. The pellets are coated and shaped at a speed of 50 r / min and a temperature of 25℃. After shaping, they are dried at a low temperature of 40℃ until the moisture content of the pellets is 8%, thus obtaining pelleted sesame seeds.

[0040] Example 3

[0041] A special base material formula for sesame seed pellets that is easy to form and coat includes, by weight: 35 parts of hydroxypropyl starch phosphate (degree of substitution 0.12), 12 parts of sodium carboxymethyl cellulose, 20 parts of vermiculite powder (200 mesh, dried at 110℃ for 3h), 25 parts of humus soil (100 mesh sieve, sterilized by high pressure steam at 121℃ for 30min), 15 parts of bentonite, 5 parts of polyethylene glycol, 3 parts of trehalose, and 40 parts of water, with 1 part of gibberellin (plant growth regulator) added.

[0042] Preparation method:

[0043] Step 1: Raw material pretreatment: Place vermiculite powder in a 105℃ oven and dry for 2 hours, then cool to room temperature for later use; sieve the humus soil through a 100-mesh screen to remove large impurities, then sterilize it with high-pressure steam at 121℃ for 30 minutes, and cool it for later use.

[0044] Step 2: Dry material mixing: Weigh each dry material component and gibberellin according to the above weight proportions, place them in a mixer, and mix at a speed of 200 r / min for 20 min to obtain a dry material mixture;

[0045] Step 3, Preparation of wet material: Weigh polyethylene glycol and trehalose, add them to water to dissolve, and obtain a mixed aqueous solution; slowly add the mixed aqueous solution to the dry material mixture while stirring, with a stirring speed of 300 r / min and a stirring time of 30 min, to obtain the wet base material;

[0046] Step 4: Curing treatment: Curing the wet base material at 70℃ for 20 minutes, then cooling to room temperature to obtain the special base material.

[0047] Application: Sesame seeds and special base material are placed in a pelleting equipment at a weight ratio of 1:5. The mixture is coated and shaped at a speed of 80 r / min and a temperature of 30℃. After shaping, the pellets are dried at a low temperature of 50℃ until the moisture content of the pellets is 12%, thus obtaining pelletized sesame seeds.

[0048] Comparative Example 1

[0049] The existing conventional base material formula is used: 25 parts ordinary starch, 8 parts sodium carboxymethyl cellulose, 15 parts talc, 20 parts garden soil, 12 parts bentonite, and 32 parts water. The preparation method and application method are the same as in Example 1.

[0050] Performance testing

[0051] The performance of sesame seed pellets prepared in Examples 1-3 and Comparative Example 1 was tested. The test indicators included pellet formation rate, coating uniformity, germination rate, and pellet strength. The test results are shown in Table 1 below:

[0052] Test sample Molding rate (%) Coating uniformity (%) Germination rate (%) Pellet strength (N) Example 1 96.5 97.2 92.3 2.8 Example 2 95.2 96.1 90.5 2.5 Example 3 97.1 97.8 94.6 3 Comparative Example 1 82.3 85.5 78.6 1.5

[0053] As can be seen from the test results in the table above, the sesame seed pellets prepared in Examples 1-3 of this invention have significantly better forming rate, coating uniformity, germination rate and pellet strength than Comparative Example 1. This fully demonstrates that the base material formula of this invention has excellent forming and coating properties, can effectively improve the germination effect of sesame seeds, and has significant technical advantages.

[0054] This test table includes 4 groups of samples (Examples 1-3 and Comparative Example 1). The numerical distribution of the four indicators shows a significant regularity: the values ​​of each indicator in the Example group are significantly higher than those in Comparative Example 1, and Example 3, due to the addition of plant growth regulators, has some indicators (germination rate and pellet strength) that are slightly better than those in Example 1 and Example 2.

[0055] Formation rate is a key indicator for evaluating the core performance of pelletized base material, directly determining the feasibility and efficiency of pelletizing. Test data shows:

[0056] The molding rates of all examples reached over 95%, with Example 1 at 96.5%, Example 2 at 95.2%, and Example 3 at 97.1%, which are at a high level and have little fluctuation. This indicates that the base material formulation of the present invention (modified starch and sodium carboxymethyl cellulose compound bonding system + bentonite thickener) can be stably molded in different component content ranges, and is suitable for the consistency requirements of industrial mass production.

[0057] The molding rate of Comparative Example 1 (conventional base material) was only 82.3%, which was 13.5 percentage points lower than the average of the Example groups, a significant difference. This is because the conventional base material uses ordinary starch as a binder, which has insufficient bonding strength, and the inert filler (talc) was not pretreated, leading to cracking and peeling during the coating process. This fully demonstrates the key role of the selection of modified starch and the raw material pretreatment process in improving molding performance.

[0058] The uniformity of coating directly affects the consistency of subsequent nutrient release and stress resistance in pelleted seeds. Data comparison shows:

[0059] The uniformity of coating in all the example groups exceeded 96%, with Example 1 at 97.2%, Example 2 at 96.1%, and Example 3 at 97.8%. The values ​​were high and stable, indicating that the substrate of the present invention has excellent adhesion to sesame seeds and can form a continuous and dense coating layer on the seed surface, avoiding local exposure or excessive coating.

[0060] Comparative Example 1 showed a coating uniformity of 85.5%, which was 11.2 percentage points lower than the average of the Example Group. The core reason is that the garden soil in the conventional base material was not screened and sterilized, resulting in more impurities and uneven particle size, which damaged the uniformity of the base material and led to uneven distribution of adhesion force during the coating process. This further confirms the necessity of the humus pretreatment process (screening + sterilization) and the uniformity design of the formulation components in this invention.

[0061] Germination rate is a core indicator for evaluating the adaptability of substrate to seed growth, and it depends on the balance between the substrate's aeration and water retention. Data difference analysis is as follows:

[0062] The germination rates of all example groups reached over 90%, with Example 1 at 92.3%, Example 2 at 90.5%, and Example 3 at 94.6%. Among them, Example 3, due to the addition of gibberellin (a plant growth regulator), further improved the germination rate, indicating that the air permeability and water retention of the substrate of the present invention achieved the best balance, which can not only prevent seeds from becoming moldy due to excessive moisture, but also continuously provide moisture and a suitable environment for seed germination.

[0063] The germination rate of Comparative Example 1 was only 78.6%, which was 12.8 percentage points lower than the average of the Example groups. This is because conventional substrates use talc as filler, which has poor air permeability and insufficient water retention, resulting in either oxygen deficiency and mold growth or water deficiency and wilting during seed germination. This highlights the technical rationality of the present invention's use of vermiculite powder (porous structure improves air permeability) and humus soil (high water retention) as a compound filler.

[0064] Pellet strength determines the integrity of pelleted seeds during storage, transportation, and mechanized sowing. Numerical comparison results show:

[0065] The pellet strength of all example groups reached above 2.5N, with Example 1 at 2.8N, Example 2 at 2.5N, and Example 3 at 3.0N. The strength is sufficient to withstand the collision and compression during mechanized sowing and prevent pellet breakage.

[0066] The pellet strength of Comparative Example 1 was only 1.5 N, less than 60% of the average level of the Example group, making it difficult to meet the requirements of mechanized sowing. The core reason is that conventional base materials lack plasticizing components such as polyethylene glycol and trehalose, resulting in brittle pellets. In contrast, this invention improves the flexibility and bonding strength of the base material by adding polyethylene glycol and trehalose, thereby significantly enhancing the pellet strength.

[0067] As can be seen from the combined values ​​of the four indicators, the test data of Examples 1-3 of this invention are significantly better than those of Comparative Example 1. The improved molding rate and coating uniformity demonstrate the superiority of the base material bonding system and pretreatment process; the increased germination rate verifies the coordinated design of air permeability and water retention; and the enhanced pellet strength ensures the feasibility of practical application. Furthermore, in Example 3, the addition of a plant growth regulator further optimized the various indicators, demonstrating the functional extensibility of the formulation of this invention.

[0068] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A formula for a special base material for sesame seed pelleting that is easy to form and coat, characterized in that, By weight, it includes the following components: 20-35 parts modified starch, 5-12 parts sodium carboxymethyl cellulose, 10-20 parts vermiculite powder, 15-25 parts humus, 8-15 parts bentonite, 2-5 parts polyethylene glycol, 1-3 parts trehalose, and 25-40 parts water.

2. The formula for a special base material for sesame seed pelleting that is easy to form and coat, as described in claim 1, is characterized in that... The modified starch is hydroxypropyl starch phosphate with a degree of substitution of 0.05-0.

12.

3. The formula for a special base material for sesame seed pelleting that is easy to form and coat, as described in claim 1, is characterized in that... The vermiculite powder has a particle size of 100-200 mesh and is dried at 105-110℃ for 2-3 hours.

4. The formula for a special base material for sesame seed pelleting that is easy to form and coat, as described in claim 1, is characterized in that... The humus soil was subjected to 100-mesh sieving and high-pressure steam sterilization at 121°C for 30 minutes.

5. The formula for a special base material for sesame seed pelleting that is easy to form and coat, as described in claim 1, is characterized in that... It also includes 0.5-2 parts of plant growth regulator or 1-3 parts of biological fungicide.

6. A method for preparing a special substrate for sesame seed pellets that is easy to form and coat, as described in any one of claims 1-5, characterized in that, Includes the following steps: Step 1: Raw material pretreatment: Place vermiculite powder in an oven at 105-110℃ and dry for 2-3 hours, then cool to room temperature for later use; humus soil is sieved through a 100-mesh sieve to remove large impurities, then sterilized by high-pressure steam at 121℃ for 30 minutes, and cooled for later use. Step 2: Dry material mixing: Weigh the modified starch, sodium carboxymethyl cellulose, pretreated vermiculite powder, humus, and bentonite according to the weight parts, place them in a mixer, and mix at a speed of 150-200 r / min for 15-20 min to obtain a dry material mixture. Step 3: Preparation of wet material: Weigh out polyethylene glycol and trehalose by weight, add them to water, and stir until completely dissolved to obtain a mixed aqueous solution; slowly add the mixed aqueous solution to the dry material mixture while stirring at a speed of 250-300 r / min for 20-30 min to obtain the wet base material; Step 4, Curing treatment: Place the wet base material in a curing device and cure it at 60-70℃ for 15-20 minutes. After curing, cool it to room temperature to obtain the special base material.

7. The application of the special substrate according to any one of claims 1-5 in the preparation of sesame seed pellets, characterized in that, The application method is as follows: Sesame seeds and special base material are placed in a pelleting equipment at a weight ratio of 1:3-1:

5. The mixture is coated and shaped at a speed of 50-80 r / min and a temperature of 25-30℃. After shaping, the pellets are dried at a low temperature of 40-50℃ until the moisture content of the pellets is 8-12%, thus obtaining sesame pelleted seeds.