Method for preparing plant-based calcium-reinforced sandwich soft gel and application of plant-based calcium-reinforced sandwich soft gel in simulated gelatin soft sweets

Abstract

The invention relates to a method for preparing plant-based calcium-reinforced sandwich soft gel and application of the plant-based calcium-reinforced sandwich soft gel in simulated gelatin soft sweets. Sodium alginate is used as a raw material, a twin-screw high-moisture extrusion technology is adopted to be coupled with a calcium ion cross-linking effect, extrusion process parameters are controlled, then a sodium alginate gel extrudate is soaked in CaCl2 solutions with different concentrations, the calcium ion concentration and the soaking time are regulated and controlled, and the plant-based calcium-reinforced sandwich soft gel rich in calcium is obtained. Compared with commercially available animal-derived gelatin-based candies, the animal-derived gelatin-based candies have similar texture characteristics and microstructures; the soft gel is composed of pure plant-based seaweed dietary fibers, is rich in calcium element, soft in taste, rich in elasticity and easy to chew, is an ideal substitute of gelatin-based candies, provides possibility for embedding of probiotics or other nutrient substances due to the special sandwich structure of the soft gel, is expected to become a new generation of nutritional, healthy and functional gel candies, and has good market prospects. The types of existing gel candies are enriched, and the green and sustainable development of the children food industry in China is promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of plant-based food development, in particular to a method for fortifying plant-based calcium-fortified sandwich soft gel and an application thereof in simulating gelatin soft candies. Background Art

[0002] Soft candies and gummy candies made with gelatin as the core gelling agent have a chewy texture and high transparency. They are deeply loved by children and have high market acceptance. However, animal farming has high carbon emissions (producing 1kg of gelatin emits 5.2kg of CO2), which does not meet environmental, social and governance standards. The production of each ton of gelatin consumes 30 tons of water, and the wastewater contains high concentrations of organic matter (COD ≥ 5000mg / L), and the treatment cost accounts for 15% of the total cost. Animal gelatin has caused EU import restrictions due to prion contamination and faces controversy over food safety and health. Due to environmental pressures, resource shortages and other issues, the world's attention to sustainable food is increasing, and the research and development of plant-based candies has become a hot topic in the field of food science.

[0003] Currently, research on plant-based foods is mainly focused on using plant proteins to simulate the texture and taste of meat products, such as simulating the fibrous structure of animal muscle tissue. However, there is less research on using plant polysaccharides to replace gelatin. Polysaccharide plant-based foods use polysaccharide colloids as the main raw material, which can be extracted from microorganisms, seaweed, etc. Because polysaccharides have multiple OH groups, they can increase the water holding capacity of plant meat by forming hydrogen bonds with water molecules. At the same time, due to the good gelling properties of polysaccharides themselves, they are more suitable for simulating animal-derived gelatin. Sodium alginate, as a natural polysaccharide, has good biocompatibility and gelling properties. However, current research on sodium alginate is more concentrated in the chemical industry, while research in the food industry, especially in the field of plant-based gel candies, is relatively limited. Therefore, the development of plant-based candies based on sodium alginate is of great significance to promoting the green and sustainable development of my country's children's food industry.

[0004] Food extrusion technology is a thermomechanical process that uses shear forces to mix and shape materials primarily composed of proteins or polysaccharides under controlled pressure and temperature. During this process, the material, containing a certain amount of water, is fed into the extruder through a feeder. The material is then transported to the cooking section by the thrust of the feed screw, where it is thoroughly mixed with water or other liquids. In the cooking section, the material is heated by the outer wall of the sleeve and the heat generated by friction on the inner wall of the sleeve. The pressure on the material exceeds the saturated vapor pressure of water at the corresponding temperature, preventing the water from evaporating and converting the material to a molten state. The pressure drops sharply as the material is extruded from the die, and the temperature drops rapidly in the cooling section, forming a product with a specific texture.

[0005] In view of the above reasons, the present invention provides a method for preparing plant-based calcium-fortified sandwich soft gel and its application in simulating gelatin soft candies. Sodium alginate is used as raw material, and high-moisture extrusion technology is adopted to couple the calcium ion cross-linking effect to prepare plant-based calcium-fortified sandwich soft gel. As an ideal substitute for gelatin-based candies, the present invention develops a new generation of nutritious, healthy, and functional gel candies, enriching the current gel candy categories. Summary of the Invention

[0006] In order to develop a new generation of nutritious, healthy, and functional gel candies that do not contain gelatin, the present invention provides a method for producing plant-based calcium-fortified sandwich soft gels, which uses twin-screw high-moisture extrusion technology coupled with the calcium ion cross-linking effect. The specific steps are as follows:

[0007] ① Sodium alginate is fed into a twin-screw extruder, wherein the feeding rate of sodium alginate is X, and the feeding rate of water is calculated according to formula A. Sodium alginate and water are mixed in the twin-screw extruder to form a sodium alginate colloid;

[0008] ② Treating the sodium alginate colloid at a temperature of 130 to 150° C. for 10 to 30 seconds, and extruding the sodium alginate colloid in a cooling system to obtain a sodium alginate gel extrudate;

[0009] ③ Soaking the sodium alginate gel extrudate in a CaCl2 solution with a mass concentration of 0.25% to 2.0% for 1 to 24 hours to obtain a plant-based calcium-fortified sandwich soft gel;

[0010] The formula A is:

[0011] The set moisture content is 60-70%.

[0012] The screw speed during the feeding process is 150-160 rpm.

[0013] The cooling system is a water circulation cooling system.

[0014] The water circulation temperature is 30-35°C.

[0015] The extrusion pressure is 0.5-5 MPa.

[0016] The feeding rate is 6-8 g / min.

[0017] The plant-based calcium-fortified sandwich soft gel is used to simulate gel candies with a gelatin addition amount of 4%-10%; and can also be used to prepare sandwich gel candy products. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The texture characteristics of plant-based calcium-fortified soft gel sandwiches at different calcium ion concentrations (a) are compared with the texture characteristics of soft candies with different gelatin addition amounts (b).

[0019] Figure 2 The microstructure of the plant-based calcium-fortified sandwich soft gel (a) and the microstructure of the gelatin soft candy (b) are compared under the same multiple conditions after being soaked in 1.0% calcium ion concentration for 6 hours.

[0020] Figure 3 The macroscopic morphology (a) and moisture distribution diagram (b) of the plant-based calcium-fortified sandwich soft gel soaked in a calcium ion concentration of 1.0% for 6 hours according to the present invention.

[0021] Beneficial effects

[0022] The present invention firstly precisely controls the moisture content used in the preparation process of the plant-based calcium-fortified sandwich soft gel, achieving a high moisture content of 60% to 70%, and sets a specific cooking temperature. The cooking temperature is a key factor affecting the transparency of the sodium alginate gel extrudate. The gel extrudate obtained under low temperature conditions has low transparency. When the cooking temperature of the present invention is maintained at 130 to 150°C, the gel extrudate has high transparency. The sodium alginate gel extrudate is immersed in solutions with different calcium ion concentrations to form a soft gel with a "sandwich" structure. This structure is characterized by the outer layer forming a denser gel layer due to the diffusion of calcium ions, while the inner layer retains a high moisture content and softness, presenting a layered feature similar to a sandwich. This structure makes it possible to encapsulate probiotics or other nutrients. The "sandwich" structure can serve as an ideal carrier for probiotics or other nutrients (such as vitamins and antioxidants), protecting them during storage and digestion, and giving them additional functional potential.

[0023] The microstructure of the plant-based calcium-fortified sandwich soft gel exhibits a regular reticular architecture, with a pore distribution and network density highly consistent with the three-dimensional microporous network structure of gelatin-agar soft candy. This similarity suggests that the calcium-induced cross-linking reaction of sodium alginate can effectively mimic the complex network formed by the combination of gelatin and agar, thereby reproducing the structural characteristics of traditional gelatin soft candy at the microscopic level. The microstructure of the soft gel of the present invention differs significantly from that of gelatin-agar soft candy in terms of formation mechanism and application potential. The microstructure of gelatin-agar soft candy relies on the protein triple helix structure of animal-derived gelatin and the heat-stable gelling properties of agar, while the soft gel of the present invention forms a gel through the ionic cross-linking reaction of sodium alginate and calcium ions. The constructed plant-based gel system not only avoids dependence on animal raw materials but also provides greater formulation flexibility for the product.

[0024] Comparisons with commercially available soft candies revealed that the plant-based calcium-fortified soft gel prepared by the method of the present invention can effectively mimic the textural properties of Biopel probiotic soft candies, meeting market demand. Further comparisons of the soft gel of the present invention with soft candies containing varying amounts of gelatin revealed that the soft gel of the present invention can effectively mimic the textural properties of soft candies containing 4% to 10% gelatin. Furthermore, due to its high moisture content, excellent water retention, soft texture, elasticity, and ease of chewing, it is an ideal alternative to gelatin-based candies. Furthermore, since it is composed of pure plant-based seaweed dietary fiber and rich in calcium, it is expected to be developed into a new generation of nutritious, healthy, and functional gel candies, enriching the existing gel candy category and promoting the green and sustainable development of my country's children's food industry. DETAILED DESCRIPTION

[0025] In order to make the objects, characteristics and advantages of the present invention more clear, the present invention will be further explained with reference to the accompanying drawings and specific embodiments below. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, modifications of various equivalent forms of the present invention by those skilled in the art will fall within the scope specified by the claims attached to this application.

[0026] In all the examples, sodium alginate was purchased from Qingdao Mingyue Seaweed Group Co., Ltd. with a water content of 10%; CaCl2 was purchased from Sinopharm Chemical Reagent Co., Ltd. and was food grade.

[0027] The twin-screw extrusion equipment is a Process 11 Hygienic co-rotating meshing twin-screw extruder purchased from Thermo Fisher Scientific Inc. in Germany. It consists of a control host (controlling the feeding rate, screw speed and temperature of each extrusion section), a feeding system (twin-screw volumetric feeder and digital peristaltic water pump), eight independent heating zones, a refrigeration cycle and a cooling die. The extruder host measures 820 mm × 480 mm × 410 mm (length × width × height), uses a screw diameter of 11 mm (screw aspect ratio of 40:1), and the end cooling die measures 25 mm × 7 mm × 4 mm (length × width × height). During the extrusion process, the electric torch heating system can independently control the temperature of each heating zone and cool it through a refrigeration cycle.

[0028] In all the following examples, the amount of water added is calculated according to the following formula (1):

[0029]

[0030] Among them, the moisture content of sodium alginate itself is measured according to the method specified in the Chinese national standard GB 5009.3-2016.

[0031] The experimental methods used in all the following examples are as follows:

[0032] 1. Texture characteristics

[0033] The textural properties of sodium alginate high-moisture extrudates were determined using a TA-XT Plus texture analyzer. Samples were cut into 20 mm x 20 mm blocks for testing. The instrument was calibrated using a 1 kg weight, and the measurement mode was set to shear mode with a probe speed of 2.0 mm / s. The HDB / BS Warner shear tool probe was used for measurement. The hardness of the samples was recorded, and each sample was measured in parallel nine times.

[0034] 2. Microstructure

[0035] The microstructure of sodium alginate high-moisture extrudate was photographed using a scanning electron microscope (SEM). The sample was cut into thin slices with a width of 1.0 mm and dried using a freeze dryer. The dried sample was gold-sprayed for 45 seconds and then placed in the SEM sample chamber. The electron gun acceleration voltage was set to 5 kV, and the sample was photographed and its microstructure observed at magnifications of 200x and 1000x, respectively.

[0036] 3. Macromorphology

[0037] The RISE-MANGA Raman image scanning electron microscope was used to photograph and observe the appearance of sodium alginate high-moisture extrudates.

[0038] 4. Moisture distribution

[0039] Magnetic Resonance Imaging (MRI): After placing the sample at the center of the measurement sample plate, the plate is placed into the low-field NMR chamber for a pre-scan. The sample is positioned so that it is centered in the imaging field of view. An MSE sequence is used to image the sample's hydrogen proton density. The image is converted from grayscale to color using pseudo-color processing and exported and saved in standard BMP format.

[0040] Data statistics and analysis

[0041] The data were processed using Microsoft Office and analyzed by ANOVA using SPSS 22.0. The same letters indicate no significant difference between the two groups of data (p < 0.05).

[0042] Example 1

[0043] The purpose of the present invention is to provide a method for preparing a plant-based calcium-fortified sandwich soft gel, which comprises the following steps:

[0044] ① Sodium alginate was fed into a co-rotating meshing twin-screw extruder at a feed rate of 6 g / min and a screw speed of 150 rpm. At the same time, the water feed rate was 6 g / min according to the set moisture content of 65% and the formula (1). Sodium alginate and pure water were mixed in the twin-screw extruder to form a sodium alginate colloid.

[0045] ② Cooking the sodium alginate colloid at 140° C. for 15 seconds, and extruding the sodium alginate colloid under the action of cooling circulating water at 30° C. to obtain a sodium alginate gel extrudate, wherein the extrusion pressure is 3 MPa;

[0046] ③ The sodium alginate gel extrudate was divided into 5 parts and soaked in a calcium ion solution with a mass concentration of 0.25% for 1 hour, 3 hours, 6 hours, 12 hours, and 24 hours, respectively, to obtain a plant-based calcium-fortified sandwich soft gel.

[0047] The five plant-based calcium-fortified soft gel sandwich samples obtained in this example were labeled as 0.25%-1h, 0.25%-3h, 0.25%-6h, 0.25%-12h, and 0.25%-24h, respectively.

[0048] Example 2

[0049] The purpose of the present invention is to provide a method for preparing a plant-based calcium-fortified sandwich soft gel, which comprises the following steps:

[0050] ① Sodium alginate was fed into a co-rotating meshing twin-screw extruder at a feed rate of 6 g / min and a screw speed of 150 rpm. At the same time, the water feed rate was 6 g / min according to the set moisture content of 65% and the formula (1). Sodium alginate and pure water were mixed in the twin-screw extruder to form a sodium alginate colloid.

[0051] ② Cooking the sodium alginate colloid at 140° C. for 15 seconds, and extruding the sodium alginate colloid under the action of cooling circulating water at 30° C. to obtain a sodium alginate gel extrudate; wherein the extrusion pressure is 3 MPa;

[0052] ③ The sodium alginate gel extrudate was divided into 5 parts, and soaked in a calcium ion solution with a mass concentration of 0.5% for 1 hour, 3 hours, 6 hours, 12 hours, and 24 hours respectively to obtain a plant-based calcium-fortified sandwich soft gel.

[0053] The five plant-based calcium-fortified sandwich soft gel samples obtained in this example were marked as 0.5%-1h, 0.5%-3h, 0.5%-6h, 0.5%-12h, and 0.5%-24h, respectively.

[0054] Example 3

[0055] The purpose of the present invention is to provide a method for preparing a plant-based calcium-fortified sandwich soft gel, which comprises the following steps:

[0056] ① Sodium alginate was fed into a co-rotating meshing twin-screw extruder at a feed rate of 6 g / min and a screw speed of 150 rpm. At the same time, the water feed rate was 6 g / min according to the set moisture content of 65% and the formula (1). Sodium alginate and pure water were mixed in the twin-screw extruder to form a sodium alginate colloid.

[0057] ② Cooking the sodium alginate colloid at 140° C. for 15 seconds, and extruding the sodium alginate colloid under the action of cooling circulating water at 30° C. to obtain a sodium alginate gel extrudate; wherein the extrusion pressure is 3 MPa;

[0058] ③ The sodium alginate gel extrudate was divided into 5 parts and soaked in a calcium ion solution with a mass concentration of 1.0% for 1 hour, 3 hours, 6 hours, 12 hours, and 24 hours, respectively, to obtain a plant-based calcium-fortified sandwich soft gel.

[0059] The five plant-based calcium-fortified sandwich soft gel samples obtained in this example were marked as 1.0%-1h, 1.0%-3h, 1.0%-6h, 1.0%-12h, and 1.0%-24h, respectively.

[0060] Example 4

[0061] The purpose of the present invention is to provide a method for preparing a plant-based calcium-fortified sandwich soft gel, which comprises the following steps:

[0062] ① Sodium alginate was fed into a co-rotating meshing twin-screw extruder at a feed rate of 6 g / min and a screw speed of 150 rpm. At the same time, the water feed rate was 6 g / min according to the set moisture content of 65% and the formula (1). Sodium alginate and pure water were mixed in the twin-screw extruder to form a sodium alginate colloid.

[0063] ② Cooking the sodium alginate colloid at 140° C. for 15 seconds, and extruding the sodium alginate colloid under the action of cooling circulating water at 30° C. to obtain a sodium alginate gel extrudate; wherein the extrusion pressure is 3 MPa;

[0064] ③ The sodium alginate gel extrudate was divided into 5 parts and soaked in a calcium ion solution with a mass concentration of 1.5% for 1 hour, 3 hours, 6 hours, 12 hours, and 24 hours, respectively, to obtain a plant-based calcium-fortified sandwich soft gel.

[0065] The five plant-based calcium-fortified sandwich soft gel samples obtained in this example were marked as 1.5%-1h, 1.5%-3h, 1.5%-6h, 1.5%-12h, and 1.5%-24h, respectively.

[0066] Example 5

[0067] The purpose of the present invention is to provide a method for preparing a plant-based calcium-fortified sandwich soft gel, which comprises the following steps:

[0068] ① Sodium alginate was fed into a co-rotating meshing twin-screw extruder at a feed rate of 6 g / min and a screw speed of 150 rpm. At the same time, the water feed rate was 6 g / min according to the set moisture content of 65% and the formula (1). Sodium alginate and pure water were mixed in the twin-screw extruder to form a sodium alginate colloid.

[0069] ② Cooking the sodium alginate colloid at 140° C. for 15 seconds, and extruding the sodium alginate colloid under the action of cooling circulating water at 30° C. to obtain a sodium alginate gel extrudate; wherein the extrusion pressure is 3 MPa;

[0070] ③ The sodium alginate gel extrudate was divided into 5 parts and soaked in a calcium ion solution with a mass concentration of 2.0% for 1 hour, 3 hours, 6 hours, 12 hours, and 24 hours, respectively, to obtain a plant-based calcium-fortified sandwich soft gel.

[0071] The five plant-based calcium-fortified sandwich soft gel samples obtained in this example were labeled as 2.0%-1h, 2.0%-3h, 2.0%-6h, 2.0%-12h, and 2.0%-24h, respectively.

[0072] Verification experiment:

[0073] Seven experimental groups were set up, and the samples obtained from the experiment were tested and analyzed. The settings of each group were as follows:

[0074] H2O (blank control group): sodium alginate extrudate in pure water without soaking;

[0075] Gelatin (control group): Gelatin soft candies with gelatin addition amounts of 4%, 6%, 8%, and 10% were prepared. The specific formulas are shown in Table 1.

[0076] Table 1 Soft candy formula with different gelatin addition amounts

[0077]

[0078] Ca 0.25% (Example 1): Five plant-based calcium-fortified soft gel sandwich samples were obtained by soaking in a calcium ion solution with a mass concentration of 0.25% for 1 h, 3 h, 6 h, 12 h, and 24 h, respectively;

[0079] Ca 0.5% (Example 2): Five plant-based calcium-fortified soft gel sandwich samples were obtained by soaking in a 0.5% calcium ion solution for 1 h, 3 h, 6 h, 12 h, and 24 h, respectively;

[0080] Ca 1.0% (Example 3): Five plant-based calcium-fortified soft gel sandwich samples were obtained by soaking in a 1.0% calcium ion solution for 1 h, 3 h, 6 h, 12 h, and 24 h, respectively;

[0081] Ca 1.5% (Example 4): Five plant-based calcium-fortified soft gel sandwich samples were obtained by soaking in a 1.5% calcium ion solution for 1 hour, 3 hours, 6 hours, 12 hours, and 24 hours, respectively;

[0082] Ca 2.0% (Example 5): Five plant-based calcium-fortified soft gel sandwich samples were obtained by soaking in a 2.0% calcium ion solution for 1 h, 3 h, 6 h, 12 h, and 24 h, respectively;

[0083] Experimental results:

[0084] Texture characteristics: such as Figure 1 As shown, when the sodium alginate high moisture extrudate is immersed in different concentrations of Ca 2+ When in solution, it can better simulate the texture characteristics of soft candy with gelatin added in an amount of 4%-10%, and the viscosity of sodium alginate itself is low after combining with calcium ions, which can reduce viscosity while maintaining moderate hardness. 2+ When soaked in the solution, the texture is very soft and there is no sandwich structure.

[0085] To further compare with commercially available soft candies, reference was made to the research results of Feng Hangting et al. on the textural properties of four commercially available gel candies. The textural properties are shown in Table 2, and sensory evaluation revealed that the Biopel probiotic soft candies scored the highest, indicating that gel candies with appropriate hardness and a certain chewiness are more in line with market demand. Comparison with the soft gels of the present invention revealed that the plant-based calcium-fortified sandwich soft gels of the present invention can better simulate the textural properties of the Biopel probiotic soft candies, meeting market demand. Furthermore, the plant-based calcium-fortified sandwich soft gels themselves have good thermal stability, allowing the soft candies to maintain their shape and taste even in high-temperature environments without the need for additional gelling agents. This improvement not only simplifies the production process but also provides consumers with a better eating experience, making it particularly suitable for markets with high thermal stability requirements.

[0086] Table 2 Texture results of four kinds of gel candies

[0087]

[0088] Microstructure: such as Figure 2As shown, the soft candy compounded with 0.8% agar and 6% cowhide gelatin was observed by SEM, showing a uniform three-dimensional network microporous structure. The pore size is mainly distributed between 100 and 150 μm, and a few are less than 100 μm. This structure is formed by the long-chain molecules of gelatin and the strong gel properties of agar, giving the soft candy moderate hardness, high elasticity and good thermal stability. Similarly, the present invention uses plant-based calcium to strengthen the sandwich soft gel, and its microstructure also shows a regular network architecture. The pore distribution and network density are highly consistent with gelatin-agar soft candy. This similarity shows that the cross-linking reaction of sodium alginate under the induction of calcium ions can effectively simulate the complex network formed by the compounding of gelatin and agar, thereby reproducing the structural characteristics of traditional gelatin soft candy at the microscopic level. The microstructure of this product is significantly different from that of gelatin-agar gummies in terms of formation mechanism and application potential. The microscopic network of gelatin-agar gummies relies on the protein triple helix structure of animal-derived gelatin and the thermally stable gel properties of agar. The present invention forms a gel through the ionic cross-linking reaction of sodium alginate and calcium ions. The constructed plant-based gel system not only avoids dependence on animal raw materials, but also gives the product greater formulation flexibility.

[0089] according to Figure 3 From the macromorphology and moisture distribution diagram, it can be found that a distinct "sandwich" structure is formed inside the plant-based calcium-fortified sandwich soft gel of the present invention. This structure is characterized by the outer layer forming a denser gel layer due to the diffusion of calcium ions, while the inner layer retains a higher moisture content and softness, presenting a sandwich-like layered feature. This structure makes it possible to encapsulate probiotics or other nutrients. The "sandwich" structure can serve as an ideal carrier for probiotics or other nutrients (such as vitamins and antioxidants), protecting them during storage and digestion, and giving them additional functional potential.

[0090] Example 6

[0091] The object of the present invention is to provide a method for preparing a plant-based calcium-fortified sandwich soft gel. The specific steps are as follows: sodium alginate is fed into a co-rotating meshing twin-screw extruder, the feed rate of the extruder is 7 g / min, the screw speed is 158 rpm, and the water feed rate is set to 8.75 g / min (calculated by substituting the set moisture content into formula (1) at 60%); sodium alginate is mixed with pure water to form a sodium alginate colloid; the cooking target temperature is set to 130° C., the sodium alginate colloid is cooked for 10 seconds, and the colloid is cooled and extruded, wherein the extrusion pressure is 0.5 MPa; the cooling water circulation temperature is 33° C. to obtain a sodium alginate gel extrudate; and the sodium alginate gel extrudate is soaked in a calcium ion solution with a mass concentration of 1.2% for 10 hours to obtain a plant-based calcium-fortified sandwich soft gel.

[0092] Example 7

[0093] The object of the present invention is to provide a method for preparing a plant-based calcium-fortified sandwich soft gel. The specific steps are as follows: sodium alginate is fed into a co-rotating meshing twin-screw extruder, the feed rate of the extruder is 8 g / min, the screw speed is 160 rpm, and the water feed rate is set to 16 g / min (calculated by substituting the set moisture content into formula (1) at 70%); sodium alginate is mixed with pure water to form a sodium alginate colloid; the cooking target temperature is set to 150° C., the sodium alginate colloid is cooked for 30 seconds, and the colloid is cooled and extruded, wherein the extrusion pressure is 5 MPa; the cooling water circulation temperature is 35° C. to obtain a sodium alginate gel extrudate; and the sodium alginate gel extrudate is soaked in a calcium ion solution with a mass concentration of 1.8% for 18 hours to obtain a plant-based calcium-fortified sandwich soft gel.

Claims

1. A method for preparing a plant-based calcium-fortified sandwich soft gel, characterized by: The preparation method of the plant-based calcium-fortified sandwich soft gel is based on a twin-screw extruder, and the specific steps are as follows: ① Sodium alginate is fed into a twin-screw extruder, wherein the feeding rate of sodium alginate is X, and the feeding rate of water is calculated according to formula A. Sodium alginate and water are mixed in the twin-screw extruder to form a sodium alginate colloid; ② Treating the sodium alginate colloid at a temperature of 130 to 150° C. for 10 to 30 seconds, and extruding the sodium alginate colloid in a cooling system to obtain a sodium alginate gel extrudate; ③ Soaking the sodium alginate gel extrudate in a CaCl2 solution with a mass concentration of 0.25% to 2.0% for 1 to 24 hours to obtain a plant-based calcium-fortified sandwich soft gel; Wherein, the formula A is: The set moisture content is 60-70%.

2. The method for preparing the plant-based calcium-fortified sandwich soft gel according to claim 1, characterized in that: The screw speed during the feeding process is 150-160 rpm.

3. The method for preparing the plant-based calcium-fortified sandwich soft gel according to claim 1, characterized in that: The cooling system is a water circulation cooling system.

4. The method for preparing the plant-based calcium-fortified sandwich soft gel according to claim 3, characterized in that: The water circulation temperature is 30-35°C.

5. The method for preparing the plant-based calcium-fortified sandwich soft gel according to claim 1, characterized in that: The extrusion pressure is 0.5-5 MPa.

6. The method for preparing the plant-based calcium-fortified sandwich soft gel according to claim 1, characterized in that: The feeding rate is 6-8 g / min.

7. An application of a plant-based calcium-fortified sandwich soft gel, characterized in that: The plant-based calcium-fortified sandwich soft gel is used to simulate gel candies with a gelatin addition amount of 4%-10%.

8. An application of a plant-based calcium-fortified sandwich soft gel, characterized in that: The plant-based calcium-fortified sandwich soft gel is used for preparing sandwich gel candy products.

Images