Method for determining 3D printing parameters of non-starch polysaccharide in starch-based food, astragalus polysaccharide composite gel and preparation method of astragalus polysaccharide composite gel

Abstract

The invention relates to the technical field of food 3D printing, and discloses a method for determining 3D printing parameters of non-starch polysaccharide in starch-based food, astragalus polysaccharide composite gel and a preparation method thereof.The method for determining the optimal printing parameters comprises the steps that a gel material for 3D printing is prepared, and the gel material is prepared from non-starch polysaccharide and starch; feeding the gel material into a 3D printer for printing, researching the influence of different printing speeds, filling rates and nozzle diameters on the quality of a formed sample through a single-factor test, evaluating the quality of the formed sample based on comprehensive printing precision and quality indexes, and determining the optimal values of the printing speeds, the filling rates and the nozzle diameters; the method for rapidly determining the 3D printing parameters of the non-starch polysaccharide in the starch-based food is provided, the astragalus polysaccharide and the wheat starch are used as raw materials, the strength of the gel material can be effectively improved, the printing precision of a formed product is improved, the problems that the interior of the gel material is refined and difficult to obtain and the like are effectively solved, the preparation method is simple, and the cost is low. Cost is low and consumed time is short.

Description

Technical Field

[0001] The present invention relates to the field of 3D printing, and in particular to a method for determining 3D printing parameters of non-starch polysaccharides in starch-based foods, an astragalus polysaccharide composite gel and a preparation method thereof. Background Art

[0002] 3D printing, also known as additive manufacturing, is a new processing and manufacturing technology that gradually emerged and developed in the late 1980s. It breaks through many limitations of traditional manufacturing processes and creates a new manufacturing model. Its working principle is that the 3D printing system, based on the model designed by CAD software, deposits materials layer by layer through precise movement of the X, Y, and Z axes, and finally shapes a physical object consistent with the design model.

[0003] Among many application fields, 3D printing technology has shown unique potential and value in food processing. At present, among the types of food processing based on 3D printing technology, extrusion molding is the most widely used. However, in the conventional mechanical processing process, the shape of the sample and the research design are largely limited by equipment and tools. For example, some complex shapes and special structures are difficult to achieve with traditional mechanical processing, or require a lot of cost and time. 3D printing additive manufacturing technology has a higher degree of design freedom. It is almost not restricted by shape and structure, and can easily realize various complex designs. Therefore, it provides an easy-to-implement and cost-effective way to manufacture foods with complex shapes and special structures. However, non-starch polysaccharides currently have the problem of difficulty in molding in 3D printing in starch-based foods. Summary of the invention

[0004] The purpose of the present invention is to solve the problem that existing non-starch polysaccharides in starch-based foods are difficult to 3D print, and to provide a method for determining 3D printing parameters of non-starch polysaccharides in starch-based foods and an astragalus polysaccharide composite gel and a preparation method thereof. The method can quickly find the optimal range of 3D printing parameters of non-starch polysaccharides in starch-based foods. The preparation method of the astragalus polysaccharide composite gel determined based on the method can overcome the problem of insufficient strength of astragalus polysaccharides themselves, making it easier to achieve the refinement of the interior of the food when using 3D printing technology to prepare astragalus polysaccharide foods, and improve the accuracy of the molded samples.

[0005] To achieve the above object, a first aspect of the present invention provides a method for determining 3D printing parameters of non-starch polysaccharides in starch-based foods, wherein the method includes: preparing a gel material for 3D printing, the preparation raw materials of the gel material including non-starch polysaccharides and starch, feeding the gel material into a 3D printer for printing, and studying the effects of different printing speeds, filling rates, and nozzle diameters on the quality of the formed samples through single-factor experiments, evaluating the quality of the formed samples based on the comprehensive printing accuracy P (%) and the quality index Q (%), and determining the optimal values of the printing speed, filling rate, and nozzle diameter;

[0006] W i is the weight (g) of the i-th formed sample, Wp is the average value (g) of the weights of all formed samples, and n is the number of formed samples participating in the evaluation;

[0007] P i is the printing accuracy of the i-th formed sample, wherein, P L is the printing accuracy of the length, P W is the printing accuracy of the width, P H is the printing accuracy of the height, and the calculation formula is as follows:

[0008] wherein, M L is the actual value of the length dimension of the formed sample, and S L is the standard value of the length dimension of the formed sample;

[0009] wherein, M W is the actual value of the width dimension of the formed sample, and S W is the standard value of the width dimension of the formed sample;

[0010] wherein, M H is the actual value of the height dimension of the formed sample, and S H is the standard value of the height of the formed sample.

[0011] By using the above method, the optimal parameters for 3D printing of non-starch polysaccharides in starch-based foods can be obtained quickly and accurately. Based on these optimal parameters for 3D printing, the formed effect of the obtained product is very good.

[0012] A second aspect of the present invention provides a method for preparing an astragalus polysaccharide composite gel, wherein the preparation method includes:

[0013] Mixing and gelatinizing raw materials including astragalus polysaccharide, wheat starch, and water to obtain a gel material;

[0014] The gel material is fed into a 3D printer for printing to obtain an astragalus polysaccharide composite gel; wherein the optimal parameters of the 3D printing are determined using the method described in the first aspect of the present invention, with a printing speed of 700-800 mm / min, a filling rate of 75-85%, and a nozzle diameter of 0.6-0.8 mm.

[0015] Astragalus polysaccharide is a water-soluble heteropolysaccharide obtained by crushing, extracting, concentrating and purifying dried Astragalus root slices. It has antiviral, anti-tumor and antioxidant functions, and has great application potential in 3D printing of nutritional formula foods.

[0016] Wheat starch is an important natural biomacromolecule polymer with advantages such as low price and easy availability. It not only plays an important role as an energy source in people’s daily diet, but is also widely used in food processing as a thickener, stabilizer, etc.

[0017] The present invention uses astragalus polysaccharide and wheat starch as raw materials, which can not only improve the flavor and nutritional value of food, but more importantly, the combination of the two, supplemented by suitable 3D printing conditions, can effectively improve the strength of the gel material, improve the printing accuracy of the molded product, and effectively solve the problem of the internal refinement of the gel material. The preparation method is simple, low-cost, and short in time. The printing parameter combination for 3D printing of astragalus polysaccharide composite gel provided by the present invention has high commercial value and application prospects.

[0018] The third aspect of the present invention provides an astragalus polysaccharide composite gel prepared according to the preparation method described in the second aspect of the present invention.

[0019] Compared with the traditional processing method, the method provided by the present invention has the following advantages:

[0020] (1) A method for rapidly determining the 3D printing parameters of non-starch polysaccharides in starch-based foods is provided;

[0021] (2) Based on the above-mentioned method for rapid determination of 3D printing parameters, an astragalus polysaccharide composite gel was prepared. The raw materials of this product are widely available, the processing is simple, and it can be customized;

[0022] (3) The prepared astragalus polysaccharide composite gel combines wheat starch and astragalus polysaccharide to obtain the nutrients of both, thereby improving the application value of the product;

[0023] (4) The printing accuracy and gel strength of the gel material are improved, and the gel material has good texture and taste;

[0024] (5) It can shorten the production cycle, reduce raw material loss, improve production efficiency and reduce costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic structural diagram of a 3D printing device;

[0026] Figure 2 It is the appearance of the gel material;

[0027] Figure 3 It is a schematic diagram of astragalus polysaccharide composite gel formed at different printing speeds;

[0028] Figure 4 It is a schematic diagram of astragalus polysaccharide composite gel formed with different filling rates;

[0029] Figure 5 It is a schematic diagram of astragalus polysaccharide composite gel formed with different nozzle diameters;

[0030] Figure 6 It is a schematic diagram of the astragalus polysaccharide composite gel prepared in Example 1;

[0031] Figure 7 It is a schematic diagram of the astragalus polysaccharide composite gel prepared in Comparative Example 1;

[0032] Figure 8 Schematic diagram of the auxiliary forming structure. Detailed Description of the Invention

[0033] The following is a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0034] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0035] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0036] In addition, the term "and / or" in the description and claims is used to describe the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0037] Non-starch polysaccharides refer to complex polysaccharides other than starch, mainly non-α-glucose polysaccharides in plant cell walls, and have various biological activities. Astragalus polysaccharide is extracted from Astragalus membranaceus and is a water-soluble non-starch polysaccharide with immune-promoting and regulating effects. Relevant research shows that the interaction between starch and non-starch polysaccharides can improve the texture and printing accuracy of gels, thereby affecting the quality and stability of the final product.

[0038] In the first aspect of the present invention, a method for determining 3D printing parameters of non-starch polysaccharides in starch-based foods is provided. The method includes: preparing a gel material for 3D printing, where the preparation raw materials of the gel material include non-starch polysaccharides and starch, feeding the gel material into a 3D printer for printing, and studying the effects of different printing speeds, filling rates, and nozzle diameters on the quality of the formed samples through single-factor experiments, evaluating the quality of the formed samples based on the comprehensive printing accuracy P(%) and quality index Q(%), and determining the optimal values of the printing speed, filling rate, and nozzle diameter;

[0039] W i is the weight (g) of the i-th formed sample, Wp is the average value (g) of the weights of all formed samples, and n is the number of formed samples participating in the evaluation;

[0040] P i is the printing accuracy of the i-th formed sample, where P L is the printing accuracy of the length, P W is the printing accuracy of the width, P H is the printing accuracy of the height, and the calculation formula is as follows:

[0041] where M L is the actual value of the length dimension of the formed sample, and S L is the standard value of the length dimension of the formed sample;

[0042] where M W is the actual value of the width dimension of the formed sample, and S W is the standard value of the width dimension of the formed sample;

[0043] where M His the actual value of the height dimension of the molded sample, S H It is the standard value of the molded sample height.

[0044] The steps of evaluating the quality of the molded sample based on the comprehensive printing accuracy P (%) and the quality index Q (%) and determining the optimal values ​​of the printing speed, the filling rate and the nozzle diameter include: in each single factor experiment, confirming that the values ​​of P and Q are not less than 95%, and taking the maximum value corresponding to the mean of P and Q as the corresponding optimal printing parameter. The single factor experiment includes single factor experiments of printing speed, filling rate and nozzle diameter. The optimal printing parameters corresponding to each single factor experiment are combined to obtain the optimal values ​​of the printing speed, filling rate and nozzle diameter.

[0045] Preferably, the method for preparing the gel material comprises: mixing the starch and water to prepare a starch solution, adding the non-starch polysaccharide to the starch solution, and heating the solution to obtain the gel material.

[0046] The second aspect of the present invention provides a method for preparing an astragalus polysaccharide composite gel, wherein the preparation method comprises:

[0047] Mixing and gelatinizing raw materials including astragalus polysaccharide, wheat starch and water to obtain a gel material;

[0048] The gel material is sent into a 3D printer for printing to obtain an astragalus polysaccharide composite gel.

[0049] The optimal parameters of the 3D printing are determined by the method described in claim 1, with a printing speed of 700-800 mm / min, a filling rate of 75-85%, and a nozzle diameter of 0.6-0.8 mm.

[0050] The present invention uses astragalus polysaccharide and wheat starch as raw materials, which can not only improve the flavor and nutritional value of food, but more importantly, the combination of the two, supplemented by suitable 3D printing conditions, can effectively improve the strength of the gel material, improve the printing accuracy of the molded product, and effectively solve the problem of the internal refinement of the gel material. The preparation method is simple, low-cost, and short in time. The printing parameter combination for 3D printing of astragalus polysaccharide composite gel provided by the present invention has high commercial value and application prospects.

[0051] Preferably, the printing speed is 700 mm / min, the filling rate is 80%, and the nozzle diameter is 0.8 mm.

[0052] Preferably, the mass ratio of the wheat starch to water is 1:4-6.

[0053] Preferably, the mass ratio of wheat starch to water is 1:5.

[0054] Preferably, the mixing process includes: mixing the wheat starch and water to obtain a wheat starch solution, and then adding the astragalus polysaccharide into the wheat starch solution and mixing. Preparing the wheat starch into a corresponding solution first and then adding the astragalus polysaccharide can make the mixing of the two more uniform.

[0055] Preferably, the mass ratio of the astragalus polysaccharide to the wheat starch solution is 1:35 - 45.

[0056] Preferably, the mass ratio of the astragalus polysaccharide to the wheat starch solution is 1:40.

[0057] Preferably, the gelatinization process includes: stirring the mixed raw materials at 85 - 95 °C for 35 - 45 min.

[0058] Preferably, during printing, the temperature of the gel material is 20 - 30 °C.

[0059] Preferably, during printing, the temperature of the gel material is 25 °C.

[0060] The third aspect of the present invention provides an astragalus polysaccharide composite gel prepared by the preparation method according to the second aspect of the present invention.

[0061] Preferably, the length and width of the astragalus polysaccharide composite gel are 21 mm respectively, and the height is 10 mm.

[0062] The present invention will be further described below with specific examples.

[0063] In the following examples and comparative examples, unless otherwise specified, reagents or instruments without indicating the manufacturer can be obtained as conventional products through commercial purchase. For those not specifying specific conditions in the examples, they are carried out according to conventional conditions or the conditions recommended by the manufacturer.

[0064] The instruments and materials involved in the present invention are specified as follows:

[0065] JA3003 electronic analytical balance (Shanghai Zanwei Weighing Instrument Co., Ltd.); TL-PRO; DF-101S constant temperature oil bath magnetic stirrer (Shanghai Qiuzuo Scientific Instrument Co., Ltd.); MC-7K centrifuge (Zhejiang Oumaike Test Instrument Co., Ltd.); pneumatic extrusion type condensation food 3D printing equipment.

[0066] Among them, for the pneumatic extrusion type condensation food 3D printing equipment, its structure is as Figure 1As shown in the figure, the 3D printing device mainly consists of four parts, namely the motion part, the pneumatic part, the extrusion part, and the deposition platform. The motion part is the three-dimensional motion platform of the printer, including the X-axis slide rail D, the Y-axis slide rail C, the Z-axis slide rail E, and the stepper motor B, etc. It is mainly used to control the motion trajectory of the nozzle, so as to print the required gel structure. The pneumatic part is mainly composed of an air pump and a pressure controller, which can adjust the air pressure in the syringe A and is the power source for the gel to be extruded at a uniform speed. The extrusion part is composed of a dispensing machine connected to the syringe. The deposition platform G is equipped with a condensation system so that the gel can quickly solidify after extrusion and maintain the stability of the printed shape. The specific structure of 3D printing has been recorded in the prior art and will not be elaborated here.

[0067] In order to ensure that the printed food can maintain the stability of its shape, the 3D printer selected in the present invention also has a condensation system, which can quickly cool and solidify the material during the printing process, thus effectively maintaining the shape of the food. For food products, to stand out in the market, not only should they be liked by the public in terms of taste, but products with personalized or unique shapes are often more likely to attract consumers' attention and thus gain a larger market share.

[0068] Deionized water was purchased from Suzhou Weileite Environmental Protection Technology Co., Ltd.; wheat starch was selected according to the standard of GB / T8883 and purchased from Henan Enmiao Food Co., Ltd.; astragalus polysaccharide was selected according to the standard of polysaccharide content of 90% and water-soluble food grade and purchased from Xi'an Ruihe Bioengineering Technology Co., Ltd.

[0069] The quality of the printed samples is evaluated based on the comprehensive printing accuracy P(%) and the quality index Q(%), and their calculation formulas are as follows:

[0070] The quality of the formed samples is evaluated based on the comprehensive printing accuracy P(%) and the quality index Q(%), and the optimal values of the printing speed, filling rate, and nozzle diameter are determined;

[0071] W i is the weight (g) of the i-th formed sample, Wp is the average value of the weights of all formed samples (g), and n is the number of formed samples participating in the evaluation;

[0072] P i is the printing accuracy of the i-th formed sample, wherein, P L is the printing accuracy of the length, P W is the printing accuracy of the width, and P H is the printing accuracy of the height. The calculation formula is as follows:

[0073] wherein, M Lis the actual value of the length dimension of the molded sample, S L is the standard value of the length dimension of the molded sample;

[0074] wherein, M W is the actual value of the width dimension of the molded sample, S W is the standard value of the width dimension of the molded sample;

[0075] wherein, M H is the actual value of the height dimension of the molded sample, S H is the standard value of the height of the molded sample.

[0076] Preparation Example 1

[0077] Weigh wheat starch and deionized water according to a mass ratio of 1:5, and add them to a dry beaker, and stir evenly to make a wheat starch solution.

[0078] Prepare astragalus polysaccharide and wheat starch solution according to a mass ratio of 1:40, and slowly add astragalus polysaccharide to the prepared wheat starch solution, and keep stirring during the process so that astragalus polysaccharide can be fully mixed with the wheat starch solution to obtain a mixed solution.

[0079] After completion of the mixing, immediately use plastic wrap to tightly seal the mouth of the beaker containing the mixed solution to prevent the evaporation of water in the beaker from affecting the concentration. Subsequently, place the sealed beaker steadily in a constant temperature oil bath stirrer, accurately control the oil bath temperature of the constant temperature oil bath stirrer at 90 °C, set the stirring time to 40 minutes, and after completion, cool the obtained gel material to 25 °, and the obtained gel material is as Figure 2 shown, and it is yellow.

[0080] The printing method in the following examples, test examples and comparative examples is as follows: Place the gel material from Preparation Example 1 in the printing cartridge of a 3D printing device, and use air pressure to push the piston to move to extrude the gel material in the printing cartridge from the nozzle to obtain astragalus polysaccharide composite gel.

[0081] Test Example 1

[0082] To study the influence of different printing speeds on the product performance.

[0083] Fix the filling rate at 80%, the nozzle diameter at 0.8 mm, and the printing speeds are set at 500 mm / min, 600 mm / min, 700 mm / min, 800 mm / min, 900 mm / min and 1000 mm / min respectively. The 3D printing forming qualities of the corresponding astragalus polysaccharide composite gels are respectively as Figure 3 (a), Figure 3 (b), Figure 3 (c), 3(d) andFigure 3 as shown in (e).

[0084] When the printing speeds are set to 500 mm / min, 600 mm / min, 700 mm / min, 800 mm / min, 900 mm / min, and 1000 mm / min respectively, the corresponding P and Q are shown in Table 1 respectively.

[0085] Table 1

[0086] Printing speed, mm / min P,％ Q,％ 500 85.32 84.72 600 91.39 90.54 700 96.78 96.20 800 92.94 91.88 900 92.58 92.21 100 89.28 89.00

[0087] Combined with Figure 3 analysis, it can be found that when the printing speed is less than 700 mm / min, the printing speed is too slow, resulting in the accumulation of gel during the 3D printing forming process, the appearance of filamentous coiling in the filling layer, seriously affecting the 3D printing forming quality, and it is very easy to occur the phenomenon of nozzle blockage; when the printing speed is greater than 900 mm / min, the printing speed is too fast, there is discontinuous printing between the gel layers caused by insufficient extrusion feeding, seriously affecting the 3D printing forming quality, and it is also found in the research that when the number of printing layers increases, the collapse of the forming layer is likely to occur; as Figure 3 shown in (c) and 3(d), when the printing speed is 700 mm / min, the printing speed of the astragalus polysaccharide composite gel is appropriate, the gel material is complete, the surface is smooth, the forming quality is good, and there is no gel overflow phenomenon and collapse of the forming layer.

[0088] The optimal 3D printing speed is obtained as 700 mm / min.

[0089] Test Example 2

[0090] To study the influence of different filling rates on the product performance.

[0091] Fix the printing speed at 700 mm / min, the nozzle diameter is 0.8 mm, and the filling rates are set to 50%, 60%, 70%, 80%, 90%, and 100% respectively. The 3D printing forming qualities of the obtained astragalus polysaccharide composite gel are respectively as Figure 4 (a), Figure 4 (b), Figure 4 (c), Figure 4 (d), Figure 4 (e) and 4(f) shown.

[0092] When the filling rates are set to 50%, 60%, 70%, 80%, 90%, and 100% respectively, the corresponding P and Q are shown in Table 2 respectively.

[0093] Table 2

[0094] Filling rate, % P,％ Q,％ 50 84.33 83.64 60 89.37 87.00 70 92.20 91.50 80 96.96 95.85 90 90.60 89.37 100 91.05 90.01

[0095] Combination Figure 4 Upon further analysis, when the filling rate is greater than 80%, there is insufficient internal support in the gel, and the printed sample deforms during the stacking process, resulting in a poor forming effect; when the filling rate is less than 80%, there will be a slight accumulation of the gel during the printing process, leading to a bulging of the formed part and affecting the 3D printing forming quality; when the filling rate is 80%, the printing accuracy is relatively high, there is sufficient internal support in the gel to maintain a stable shape, and at the same time, excessive material accumulation can be avoided, taking into account both the printing efficiency and the forming quality.

[0096] Therefore, the optimal filling rate is obtained as 80%.

[0097] Test Example 3

[0098] To study the influence of different nozzle diameters on the product performance.

[0099] The printing speed is fixed at 700 mm / min, the filling rate is 80%, and the nozzle diameters are set to 0.4 mm, 0.8 mm, 1.2 mm, and 1.5 mm respectively. The 3D printing forming qualities of the corresponding astragalus polysaccharide composite gel are respectively as Figure 5 (a), Figure 5 (b), Figure 5 (c) and Figure 5 (d) shown.

[0100] When the nozzle diameters are set to 0.4 mm, 0.8 mm, 1.2 mm, and 1.5 mm respectively, the corresponding P and Q are shown in Table 3.

[0101] Table 3

[0102] Nozzle diameter, mm P,％ Q,％ 0.4 84.69 84.32 0.8 97.15 96.73 1.2 93.56 92.89 1.5 90.50 89.97

[0103] Combination Figure 5 Upon further analysis, the smaller the nozzle diameter, the higher the 3D printing forming quality. When the nozzle diameter is 0.4 mm, a relatively large extrusion pressure is required for printing, and the printing time and the platform condensation time are too long, increasing the machine wear; when the nozzle diameters are 1.2 mm and 1.5 mm, there are voids and disconnections in the interlayer connection of the printed sample, resulting in insufficient internal support of the sample and a poor forming quality; when the nozzle diameter is 0.8 mm, the interlayer connection of the printed sample is tight without gaps, and at the same time, the nozzle is not easily blocked, and the forming quality is good.

[0104] The optimal nozzle diameter is obtained as 0.8 mm.

[0105] Example 1

[0106] The printing speed of the 3D printing process parameters is set to 750 mm / min, the filling rate is 80%, and the nozzle diameter is 0.8 mm. The obtained product is as Figure 6 shown.

[0107] From Figure 6 It can be found that the formed quality of the astragalus polysaccharide composite gel with the optimal 3D printing process parameters is excellent, without gel overflow and collapse of the formed layer, and the gel is extruded smoothly during the printing process without nozzle clogging. The comprehensive printing accuracy P of the printed sample after optimization is 99.56%, and the quality index Q is 99.30%, which is 3% higher than that of Comparative Ratio 1. The overall forming effect of the printed sample is good and the printing accuracy is high.

[0108] Example 2

[0109] To further obtain more personalized products, this example provides a method for preparing a multi-morphological astragalus polysaccharide composite gel. The difference between this example and Example 1 is only that: on the basis of Example 1, an auxiliary forming structure is added, such as Figure 8 As shown, the auxiliary forming structure includes a cooling pipe 2 and an atomizing device 3 connected thereto. At least one such cooling pipe 2 is provided between the nozzle 1 of the 3D printing device and its deposition platform. In this example, two such cooling pipes 2 are provided, and the outlets of the two cooling pipes 2 face each other. Before the gel material extruded from the nozzle 1 falls onto the deposition platform of the 3D printing device, it can freely pass through the gap between the two cooling pipes 2.

[0110] The atomizing device 3 is filled with a forming auxiliary liquid, and the forming auxiliary liquid includes edible oil. After the edible oil is atomized by the atomizing device 3, it flows through the cooling pipe 2 and is sprayed out from its outlet end and adheres to the gel material coming out of the nozzle 1, so that good separability can be achieved between the gel materials formed at different stages. For example, when printing to a certain place and it is necessary to make the front and back parts of the 3D printed product have separability, the edible oil can be sprayed for 5 - 10 s at this time, so that the edible oil is evenly adhered to the gel material during this period. Then, the atomizing device 3 is turned off and 3D printing is continued for a period of time. After obtaining the product with the required shape, the printing is stopped, and then the parts of the product that need to be separated are disassembled.

[0111] The 3D printing method provided in this example can obtain personalized products according to customer needs, and for products with complex shapes, there is no need to shut down the machine. On the basis of realizing continuous printing, it can effectively ensure the separability of the parts with separation requirements. For example: when it is necessary to form an astragalus polysaccharide composite gel with an overall "pagoda structure" and each layer separable, the edible oil can be sprayed regularly and quantitatively when printing the transition structure between the Nth layer tower body and the (N + 1)th layer tower body. When eating this astragalus polysaccharide composite gel, the Nth layer tower body and the (N + 1)th layer tower body can be quickly separated smoothly. This not only ensures the aesthetics of the overall complex-shaped astragalus polysaccharide composite gel, but also takes into account its fast and smooth separability, facilitating shared consumption / use by multiple people.

[0112] Comparative Example 1: The printing speed of this comparative example was 800 mm / min, the filling rate was 100%, the nozzle diameter was 1.2 mm, and the obtained product was as Figure 7 (d), Figure 7 (f) and Figure 7 (c) shown.

[0113] From Figure 7 it can be found that: the printing speed of the sample was moderate, the surface of the printed and formed sample was smooth, and the shaping effect was good; however, the filling rate was too high, resulting in slight stacking of the sample during printing; and the nozzle diameter was too large, and the interlayer gap of the printed sample was too wide, resulting in the sample being unable to obtain sufficient gel for filling and connection during printing. The comprehensive printing accuracy P of the printed sample was 96.28%, and the quality index Q was 95.97%.

Claims

1. A method for determining 3D printing parameters of non-starch polysaccharides in starch-based foods, characterized in that: The method comprises: preparing a gel material for 3D printing, wherein the raw materials for preparing the gel material include non-starch polysaccharides and starch, feeding the gel material into a 3D printer for printing, and studying the influence of different printing speeds, filling rates and nozzle diameters on the quality of molded samples through a single factor experiment, evaluating the quality of the molded samples based on the comprehensive printing accuracy P (%) and the quality index Q (%), and determining the optimal values ​​of the printing speed, filling rate and nozzle diameter; W i is the weight of the i-th molded sample (g), Wp is the average weight of all molded samples (g), and n is the number of molded samples involved in the evaluation; P i is the printing accuracy of the i-th molding sample, Among them, P L is the printing accuracy of length, P W is the printing precision of width, P H For high printing accuracy, the calculation formula is as follows: Among them, M L is the actual length dimension of the molded sample, S L It is the standard value of the length dimension of the molded sample; Among them, M W is the actual value of the width of the molded sample, S W It is the standard value of the width dimension of the molded sample; Among them, M H is the actual value of the height dimension of the molded sample, S H It is the standard value of the molded sample height.

2. The method according to claim 1, wherein: The preparation method of the gel material comprises: mixing the starch and water to prepare a starch solution, then adding the non-starch polysaccharide into the starch solution, and heating the solution to obtain the gel material.

3. A method for preparing an astragalus polysaccharide composite gel, characterized in that: The preparation method comprises: Mixing and gelatinizing raw materials including astragalus polysaccharide, wheat starch and water to obtain a gel material; The gel material is sent into a 3D printer for printing to obtain an astragalus polysaccharide composite gel; The optimal parameters of the 3D printing are determined by the method described in claim 1, with a printing speed of 700-800 mm / min, a filling rate of 75-85%, and a nozzle diameter of 0.6-0.8 mm.

4. The preparation method according to claim 3, wherein The printing speed is 700 mm / min, the filling rate is 80%, and the nozzle diameter is 0.8 mm; And / or, the mass ratio of the wheat starch to water is 1:4-6, preferably 1:

5.

5. The preparation method according to claim 3 or 4, wherein The mixing process includes: mixing the wheat starch and water to obtain a wheat starch solution, and then adding the astragalus polysaccharide into the wheat starch solution and mixing.

6. The preparation method according to claim 5, wherein: The mass ratio of the astragalus polysaccharide to the wheat starch solution is 1:35-45, preferably 1:

40.

7. The preparation method according to claim 3, 4 or 6, wherein: The gelatinization process includes: stirring the mixed raw materials at 85-95° C. for 35-45 minutes.

8. The preparation method according to claim 7, wherein: During the printing, the temperature of the gel material is 20-30°C, preferably 25°C.

9. An astragalus polysaccharide composite gel prepared according to the preparation method according to any one of claims 3 to 8. 10 . The astragalus polysaccharide composite gel according to claim 9 , wherein the length and width of the astragalus polysaccharide composite gel are 21 mm respectively, and the height is 10 mm.

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