Pectin gel and preparation method therefor

Abstract

The present application provides a pectin gel and a preparation method therefor. The pectin gel comprises pectin and a fat-soluble substance. The pectin comprises pectin. The weight-average molecular weight of the pectin is in the range of 5.0*10^4 Da to 6.0*10^5 Da, and the polydispersity index is 1 to 6. In the structural domains of the pectin, HG > 30 mol%, and RG-1 ≤ 35 mol%; HG is homogalacturonan, and RG-1 is rhamnogalacturonan type I. The emulsion stability of the pectin gel prior to molding is high. Thus, the molded pectin gel has good textural stability, low water syneresis and oil exudation, and a good mouthfeel.

Description

A pectin gel and its preparation method Technical Field

[0001] This application belongs to the field of food and pharmaceutical technology, specifically relating to a pectin gel and its preparation method. Background Technology

[0002] Pectin is an acidic heteropolysaccharide composed of D-galacturonic acid linked by α-1,4-sugars. It is widely found in the cell walls of higher plants, accounting for approximately 30%–35%, and is a natural, green, and healthy polymer. Pectin possesses excellent properties in hemostasis, antibacterial activity, lipid-lowering effects, and detoxification, making it widely used in health products, food additives, cosmetics, and pharmaceuticals. Furthermore, pectin can regulate cell osmotic pressure and pH; when added to a certain amount of water, it can form a chewable gel with a specific hardness and modulus.

[0003] In recent years, pectin has been widely used as a food additive in the food, pharmaceutical, and health product industries to prepare gels containing fat-soluble substances. During related research, it was found that when the oil loading (e.g., OMEGA-3, derived from algal oil, fish oil, flaxseed oil, etc.) of pectin gels is ≥10%, the system exhibits poor compatibility in terms of gelation and emulsification properties. This can lead to larger oil droplet sizes, lateral shifts in the particle size distribution of fat-soluble components, or a loose gel structure with insufficient water-locking and oil-holding capacity, resulting in "oil separation and water exudation." Furthermore, the higher the oil loading, the worse the product's appearance stability.

[0004] Current research on pectin gels containing fat-soluble substances has some aspects. For example, the combination of stabilizers improves water-oil separation and texture issues. However, due to the need for oil retention stability, the stabilizers introduced are mainly saturated / hydrogenated fatty acids, which pose a risk of introducing trans fatty acids, potentially affecting digestion and metabolism in humans. Another example is the replacement of sugar, the main component of the plant-based gum gel matrix, with artificial sweeteners. The texture of plant-based gum gums is maintained through the combination and ratio of different types of sweeteners, but this method, with an oil loading of ≥10%, has limitations. It is prone to oil separation and water exudation, affecting appearance and the eating experience, as well as the stability of fat-soluble substances in the pectin gel, further impacting human digestion and absorption. Especially for plant-based gum gels with an oil loading of ≥10%, the existence of a water-oil interface requires a compatible and stable system of droplets before texture development and further texture improvement. This patent does not cover this technological scope.

[0005] Therefore, further improving the stability of pectin gel emulsions containing fat-soluble substances, in order to enhance the textural stability of pectin gels and reduce water separation and oil precipitation, is of great significance for further improving the performance of pectin gel products. Summary of the Invention

[0006] To address the problems and shortcomings of the existing technology, this application provides a pectin gel and its preparation method. The pectin gel has high emulsion stability before molding, so the molded pectin gel has good textural stability, low water and oil separation, and good taste.

[0007] According to a first aspect of this application, a pectin gel is provided, comprising pectin and a fat-soluble substance; the pectin comprises pectin; the weight-average molecular weight of the pectin is in the range of 5.0*10^4 to 6.0*10^5 Da, and the polymer dispersion coefficient is 1 to 6; in the structural domains of the pectin, HG > 30 mol%, RG-1 ≤ 35 mol%; HG is homogalacturonic acid polysaccharide, and RG-1 is rhamnuronic acid polysaccharide type I.

[0008] When pectin is combined with fat-soluble substances, the fat-soluble substances can fill the gaps in the pectin gel network, interacting with pectin molecules and enhancing gel stability. However, potential antagonistic interactions can affect the textural stability and oil exudation properties of pectin gels, thus impacting their mouthfeel. This is particularly true for pectin gels containing high levels of fat-soluble substances, whether high-sugar or low-sugar, which are prone to oil exudation, affecting both textural stability and mouthfeel. Therefore, further improving the textural stability of pectin gels containing high levels of fat-soluble substances, reducing oil exudation, and enhancing their mouthfeel are crucial for the further development of pectin gels.

[0009] Therefore, by controlling the weight-average molecular weight, polymer dispersion index (PDI), HG, and RG-1 of pectin, this application effectively improves the stability of the mixture (emulsion) before molding, thereby improving the textural stability of the molded pectin gel, effectively reducing the water and oil separation of the pectin gel, greatly improving the storage stability of the pectin gel, and improving the taste of the pectin gel.

[0010] Specifically, firstly, regarding the weight-average molecular weight of pectin, if it is too small, the inter-chain interactions are weak, and there is a lack of sufficient chain length to construct a stable three-dimensional gel network structure. Even if a gel is formed, its strength is very weak because the short molecular chains result in fewer connection points between molecules, and the constructed gel network is not tight or strong enough. Ultimately, this leads to insufficient elasticity and poor textural stability in the pectin gel. The insufficient tightness and strength of the gel network also leads to problems such as easy water and oil separation. If it is too large, pectin has poor solubility and is not easy to form a uniform and stable system with other materials. In particular, emulsion systems are more easily affected. Moreover, if the conditions are not properly controlled, a gel may not be formed or an uneven gel may be formed. If a gel is formed, it will result in excessive strength and hard texture, affecting the taste. It also lacks elasticity and flexibility, making it easy to break when subjected to external forces, which will also affect the storage stability of the pectin gel.

[0011] Secondly, regarding the Polymer Dispersion Index (PDI), a high PDI indicates a wide molecular weight distribution in pectin, encompassing molecules of various molecular weights. During gel formation, molecules of different molecular weights exhibit different gelation behaviors, making it difficult to accurately control the gel formation time and resulting in unstable gel quality. This can lead to localized over-gelation or under-gelation, affecting the textural stability and mouthfeel of the pectin gel, while also increasing the likelihood of water and oil separation. Conversely, a low PDI, due to the generally complex formulation of pectin gels and the interactions between its components, suggests relatively fixed pectin properties. This may prevent the formation of diverse synergistic effects with other components, leading to reduced overall textural stability and increased water and oil separation in the pectin gel.

[0012] Third, regarding HG and RG-1, pectin is a complex polysaccharide found in plant cell walls, containing domains such as homogalacturonic acid (HG) and rhamnogalacturonic acid I (RG-1). HG is the main domain of the pectin molecule, a linear homopolymer of α-1,4-galacturonic acid, known as the "smooth region," reflecting the gel properties of the main component. RG-1 has highly branched characteristics, known as the "hair region," and its side chains have a strong water-binding capacity and a stable gel network structure. When the HG content is too low, the number of cross-linking points between pectin molecules decreases, making it difficult to form a stable three-dimensional network structure. This leads to reduced gel strength and poor structural stability, making it more sensitive to changes in environmental factors such as temperature, pH, and ionic strength. The resulting water-oil emulsion has even worse stability, resulting in pectin gels that not only have poor textural stability but are also more prone to water and oil separation after molding. This application controls the HG content to >30 mol%, effectively ensuring the high stability of the water-oil emulsion, resulting in high strength of the formed pectin gel oil, further guaranteeing its good textural stability and reducing the amount of oil separation through water. RG-1 has abundant neutral sugar side chains, which can increase the flexibility and steric hindrance of pectin molecules, giving the gel better elasticity. When the RG-1 content is too high, the elasticity of the gel will be further enhanced, which may lead to excessive elasticity. This causes the gel to easily deform under external force, and this rebound force may destroy the original internal structure of the gel, making the gel texture loose and reducing its stability. Furthermore, when multiple excessively elastic pectin gels are stacked or in contact with each other, they cannot maintain their respective shapes under the action of gravity or other external forces, but are easily squeezed and deformed, or even fused together, affecting the stability of the entire system. Therefore, this application controls the RG-1 content to ≤35 mol%, which helps to avoid the excessive elasticity of the pectin gel affecting its overall textural stability and reducing the amount of oil separation through water.

[0013] It is important to note that pectin gel is a formulation system in which pectin, fat-soluble substances, and other materials interact to a certain extent. This application achieves a more balanced and stable interaction among the components in pectin gel by controlling the weight-average molecular weight, polymer dispersion index (PDI), HG, and RG-1 values ​​of pectin. In particular, it promotes the stable existence of fat-soluble substances in the mixture system, further optimizes the stability of the mixture (emulsion) and the textural stability of the formed pectin gel, reduces the amount of water and oil separation in the pectin gel, and improves its storage stability and taste.

[0014] In some embodiments, the weight-average molecular weight of pectin ranges from 8.0*10^4 to 5.0*10^5 Da, and the polymer dispersion coefficient is 1 to 4. Further adjusting the weight-average molecular weight and polymer dispersion coefficient of pectin is more beneficial to the overall stability of the mixture, and thus more conducive to obtaining pectin gel with higher textural stability, less oil separation in water, and better taste.

[0015] In some embodiments, the molecular weight of pectin is determined using a multi-angle laser light scattering instrument.

[0016] In some embodiments, the HG domains of pectin contain 40–90 mol% and RG-1 domains containing 4–30 mol%. Furthermore, if the HG is too large, the strong intermolecular forces can easily lead to dehydration and shrinkage. This causes water to be squeezed out of the gel, reducing its volume and making it denser, thus affecting the product's appearance and quality. If the RG-1 is too small, the gel's elasticity and toughness will be significantly reduced, making it more fragile and prone to breakage. Therefore, further limiting the HG and RG-1 to specific ranges is not only more beneficial for obtaining a stable water-oil emulsion system, but also for obtaining a pectin gel that better balances textural stability, oil extraction, and taste.

[0017] In some implementations, HG = GalA - Rha, RG-1 = 2Rha + Ara + Gal; GalA is mol% of galacturonic acid, Rha is mol% of rhamnose, Ara is mol% of arabinose, and Gal is mol% of galactose, wherein the mol% of HG and RG-1 are obtained as follows:

[0018] a. The content (Wt) of GalA galacturonic acid, Gal galactose, Rha rhamnose, Ara arabinose, Xyl xylose, Glc glucose, and Fructose in 100g of pectin was determined by ion chromatography; b. The corresponding molar number M and their sum M were calculated based on the specific molar mass of each substance. 总 According to mol% = M / M 总*The corresponding molar percentage is obtained by calculating 100%. Related research shows that the approximate values ​​of HG and RG-1 obtained using the above formula are quite close to the actual values. Therefore, the HG and RG-1 values ​​calculated using the above formula are relatively accurate.

[0019] In some embodiments, the pectin gel further includes sugar alcohols, including a first sugar alcohol and a second sugar alcohol; the first sugar alcohol includes xylitol; the second sugar alcohol includes at least one of maltitol and sorbitol; or, the sugar alcohol includes a first sugar alcohol, a second sugar alcohol, and a third sugar alcohol; the third sugar alcohol includes erythritol. Sugar alcohols can regulate the water activity and solids content of the system, creating more favorable conditions for pectin to form a gel. Regarding the types of sugar alcohols, sugar alcohols generally have a high content in pectin gels, thus having a significant impact on the overall performance of the pectin gel. This application, by selecting specific types of sugar alcohols in combination, enables them to have a good interaction with pectin and fat-soluble substances, thereby further promoting the textural stability of the pectin gel, reducing its water exudation and oil separation, and improving its taste.

[0020] In some embodiments, the sugar alcohol includes a first sugar alcohol and a second sugar alcohol, and the mass ratio of the first sugar alcohol to the second sugar alcohol is 1–30:0.09–65; or, the sugar alcohol includes a first sugar alcohol, a second sugar alcohol, and a third sugar alcohol, and the mass ratio of the first sugar alcohol, the second sugar alcohol, and the third sugar alcohol is 1–30:0.09–65:0.1–10. Further control of the types and proportions of sugar alcohols leads to a more balanced interaction between sugar alcohols and substances such as pectin and fat-soluble substances, without affecting the performance of each substance. This is more conducive to maintaining the balance and stability of the water-oil emulsion, thereby optimizing the textural stability of the formed pectin gel, reducing water and oil separation, and improving the taste of the pectin gel.

[0021] In some embodiments, the mass ratio of pectin, sugar alcohol, and fat-soluble substances is 0.5–5:10–70:5–50. Further limiting the mass ratio of pectin, sugar alcohol, and fat-soluble substances within a certain range is more conducive to the interaction of these three substances, and also to their interaction with other substances in the pectin gel system. This promotes the balance and stability of the water-oil emulsion, further optimizes the textural stability of the molded pectin gel, reduces water and oil separation, and improves the texture of the pectin gel.

[0022] In some embodiments, the pectin gel further includes an emulsifier. The mass ratio of pectin, sugar alcohol, fat-soluble substances, and emulsifier is 0.5–5:10–70:5–50:0.02–1. Emulsifiers are a key factor in the stability of water-oil emulsions; therefore, they need to be added to stabilize the emulsion. Controlling the amount of emulsifier within a certain range is more conducive to the stability of the water-oil emulsion, and thus more conducive to obtaining a pectin gel with high textural stability, low oil separation from water, and good taste.

[0023] In some embodiments, pectin accounts for 1 to 4% of the mass of the raw materials used to prepare pectin gel.

[0024] In some implementations, the degree of esterification of pectin is >50%.

[0025] In some embodiments, the fat-soluble substances include fat-soluble physiologically active substances, including at least one of the following: DHA algal oil, oil-soluble vitamins, evening primrose oil, arachidonic acid, linolenic acid oil, gamma-linolenic acid oil, caprylic / capric triglyceride (MCT), safflower seed oil, milk thistle seed oil, maple seed oil, walnut oil, fish oil, coenzyme Q10, rice bran fatty alkyl alcohols, pumpkin seed oil, borage oil, acetylsalicylic acid, fat-soluble statins, antibiotics, naproxen, and antihistamines.

[0026] In some embodiments, the pectin gel further includes an acidity regulator, wherein the mass ratio of pectin to acidity regulator is 0.5–5:0.5–7.5.

[0027] In some embodiments, the emulsifier includes at least one selected from modified starch, phospholipids, gums, acetylated pectin, cholesterol, lanolin, saponins, polysaccharides, and proteins.

[0028] In some embodiments, modified starch includes esterified starch; phospholipids include at least one of soybean phospholipids, modified phospholipids, and enzymatically hydrolyzed phospholipids; and gums include gum arabic.

[0029] In some embodiments, the acidity regulator includes at least one of citric acid, sodium citrate, potassium citrate, malic acid, and lactic acid.

[0030] In some embodiments, the pectin gel further comprises metal ions, including calcium ions. In some embodiments, the calcium ions are provided by calcium salts, including at least one selected from calcium lactate, calcium citrate, tricalcium phosphate, calcium hydrogen phosphate, milk mineral salts, calcium gluconate, and calcium chloride.

[0031] According to a second aspect of this application, a method for preparing the above-mentioned pectin gel is provided, comprising the following steps: aqueous phase preparation: pectin, a portion of sugar alcohol, and an acidity regulator are mixed evenly to obtain a gel premix; water, the remaining sugar alcohol, and deformed starch are mixed evenly, and the gel premix is ​​added thereto, and heated until completely dissolved to obtain an aqueous phase; oil phase preparation: fat-soluble substances are heated and mixed until the liquid is uniform to obtain an oil phase; emulsification: the oil phase is added to the aqueous phase and mixed evenly, and high-speed shear emulsification is performed at 70-95°C to obtain an emulsion; formulation: the acidity regulator and water are mixed and mixed at 70-80°C until completely dissolved, and then added to the emulsion and mixed for 5-10 minutes to obtain a liquid; molding: the liquid is poured onto a blister pack, then sealed, and allowed to stand for 40-60 hours to stabilize and form.

[0032] In some embodiments, during the preparation of the above-mentioned pectin gel, glycerol is added during the preparation of the aqueous phase, and the mass ratio of pectin to glycerol is 0.5-5:0.1-8. Attached Figure Description

[0033] Figure 1 is a schematic diagram of the centrifugal stability test of the mixture liquid (water-oil emulsion) in Examples 1-5 and Comparative Examples 1-2 of this application.

[0034] Figure 2 is a schematic diagram of the thermal stability test of the mixture (water-oil emulsion) in Examples 1-5 and Comparative Example 1 of this application. Detailed Implementation

[0035] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments.

[0036] In this application, the pectin used in the examples and comparative examples is selected from standard commercial materials, and the material standards meet the requirements of GB 25533. Table 1 below shows the parameter information of each pectin regarding Mw, PDI, HG, and RG-1:

[0037] Table 1. Summary of parameter information for each pectin regarding Mw, PDI, HG, and RG-1.

[0038] Examples and Comparative Examples

[0039] 1. Using pectin Mw and / or PDI as variables, investigate the effects of Mw and / or PDI on water-oil emulsions and the formed pectin gel.

[0040] A total of 6 embodiments and 3 comparative examples were set up above, and the formulations of each embodiment and comparative example are shown in Table 2.

[0041] Table 2 shows the formulations of Examples 1-6 and Comparative Examples 1-3.

[0042] 2. The effect of the type and ratio of sugar alcohols in pectin on the water-oil emulsion and the formed pectin gel.

[0043] A total of 15 embodiments are set up above, and the formulations of each embodiment are shown in Tables 3-1, 3-2 and 3-3.

[0044] Table 3-1 Formulations of Examples 7-12

[0045] Table 3-2 Formulations of Examples 13-18

[0046] Table 3-3 Formulations of Examples 19-21

[0047] 3. Using HG and / or RG-1 of pectin as variables, investigate the effects of HG and / or RG-1 on water-oil emulsions and the formed pectin gel.

[0048] A total of 3 embodiments and 1 comparative example were set up above, and the formulations of each embodiment and comparative example are shown in Table 4.

[0049] Table 4. Formulations of Examples 22-24 and Comparative Example 4

[0050] Test case

[0051] 1. Experimental Construction Method

[0052] (1) Preparation of pectin gel: Pectin gels were prepared according to the formulations in all the above examples and comparative examples. The specific preparation steps are as follows:

[0053] Aqueous phase preparation: Pectin, a portion of sugar alcohol, and a portion of acidity regulator (sodium citrate, citric acid) are mixed evenly to obtain a gel premix; water, the remaining sugar alcohol (if any, "if any" means that the sugar alcohol can also be added directly when preparing the gel premix), modified starch, and glycerol are mixed evenly, the gel premix is ​​added to it, and the mixture is heated until completely dissolved to obtain an aqueous phase;

[0054] Oil phase preparation: The fat-soluble substance (DHA algal oil) is heated to 90℃ (if there are multiple fat-soluble substances, it is necessary to heat until they are mixed evenly, and then keep warm) and kept warm to obtain the oil phase;

[0055] Emulsification: The oil phase is added to the aqueous phase and mixed evenly. High-speed shear emulsification is performed at 90°C to obtain an emulsion. Blending: The remaining acidity regulator (citric acid) and water are mixed and stirred at 70-80°C until completely dissolved. The mixture is then added to the emulsion and stirred for 5-10 minutes to obtain a liquid.

[0056] Molding: Pour the liquid material onto the blister pack, then seal it and let it stand for 48 hours to stabilize and form.

[0057] (2) Performance Testing

[0058] ① Emulsion stability test

[0059] a. Centrifugal stability

[0060] Take 10g of the unformed pectin gel (liquid) after preparation into a centrifuge tube, equilibrate in a 75℃ water bath for 30min, centrifuge at 3000rpm for 10min, and observe and record the separation of the emulsion gel.

[0061] b. Thermal stability

[0062] Take 10g of the unformed pectin gel (liquid) after preparation and place it in a centrifuge tube. Heat it in a 90℃ water bath for 1 hour. After taking it out, centrifuge it at 3000rpm for 10 minutes and observe and record the separation of the emulsion gel.

[0063] c. Freeze-thaw stability

[0064] Take 10g of the unformed pectin gel (solid solution) after preparation and place it in a centrifuge tube, seal it with an aluminum foil bag, and store it in a -20℃ refrigerator for 24 hours. Take it out and thaw it at room temperature for 24 hours, then centrifuge it at 3000rpm for 10 minutes, and observe and record the separation of the emulsion gel.

[0065] ② Water flow test

[0066] Place 10g of the stabilized pectin gel in a standard open container and put it in a constant temperature drying oven at 25±2℃ and 20~30%RH for 24h and 48h. The weight loss on drying / % = (M1-M2) / M1, and the drying equilibrium = |(M1-M3) / M1-weight loss on drying|. Repeat 3 times and take the average value. Wherein, M1 represents the weight before drying, M2 represents the weight after 24h drying, and M3 represents the weight after 48h drying.

[0067] ③ Texture test

[0068] The SMS TAXTplus texture analyzer was used in TPA testing mode. Testing speed: 1 mm / s before test, 3 mm / s during test, 3 mm / s after test, trigger force: 5 g, target mode: 50% deformation. The pectin gel size and shape were controlled to be consistent, round disc shape, 1.5 g / particle, with 6 parallel tests per sample group.

[0069] ④ Disintegration time limit

[0070] According to USP <2040> The test was conducted using water as the medium.

[0071] (3) Evaluation criteria

[0072] The relevant properties of the emulsions (solutions) and the molded pectin gels in the examples and comparative examples were evaluated according to the evaluation criteria in Table 5 below.

[0073] Table 5 Evaluation Criteria

[0074] 2. Experimental Results

[0075] The performance evaluation results of the emulsions (liquids) and the molded pectin gels in the examples and comparative examples are shown in Tables 6-1 and 6-2.

[0076] Table 6-1 Performance evaluation results of Examples 1-21

[0077] Table 6-2 Performance evaluation results of Examples 22-24 and Comparative Examples 1-4

[0078] As shown in Tables 6-1 and 6-2, this application effectively improves the stability of the pre-molding mixture (emulsion) by controlling the weight-average molecular weight of pectin, the polymer dispersion index (PDI), and limiting the types of sugar alcohols used. This improves the textural stability of the molded pectin gel, effectively reduces the water and oil separation of the pectin gel, greatly improves the storage stability of the pectin gel, and improves the taste of the pectin gel. For details, please refer to the performance data in Examples 1 to 24.

[0079] In Comparative Examples 1 and 2, the weight-average molecular weight (Mw) of pectin was too low and too high, respectively. Both were detrimental to the formation of a stable emulsion in the mixture (emulsion), and also to the textural stability of the formed pectin gel, even affecting its formation. Therefore, Comparative Examples 1 and 2 exhibited severe oil-water separation after centrifugation. Refer to Figure 1 for the centrifuge tube images of Comparative Examples 1 and 2; the centrifuged emulsions or oil-water mixtures showed some or severe separation. In contrast to Comparative Examples 1 and 2, further referring to Figure 1, it can be seen that the weight-average molecular weight (Mw) of Examples 1-5 was within a suitable range, resulting in good stability of their emulsions after centrifugation and no obvious separation. Because Comparative Examples 1 and 2 could not form a relatively stable emulsion, they could not be formed into pectin gels, or the textural stability of the formed pectin gel decreased, resulting in high water and oil separation, low overall evaluation scores, and thus, the pectin gels were unqualified. Furthermore, referring to Figure 2, it can be seen that the emulsion in Comparative Example 1 has worse thermal stability compared to Examples 1-5. This also indicates that the overall stability of the emulsion in Comparative Example 1 is poor, which is not conducive to the preparation of pectin gel with high textural stability and low water and oil separation.

[0080] In Comparative Example 3, the pectin polymer dispersion coefficient was too high, and the pectin molecular weight distribution was too wide, resulting in decreased emulsion stability and unstable gel quality. This led to localized over- or under-gelation, affecting the textural stability of the pectin gel and resulting in a lower overall evaluation score. It was also more prone to water and oil separation, making the pectin gel unqualified. In Comparative Example 4, the pectin HG and RG-1 were relatively small, leading to decreased emulsion stability and relatively poor textural stability of the molded pectin gel. It also had a relatively high amount of water and oil separation, resulting in a lower overall evaluation score and making the pectin gel unqualified.

[0081] Further comparing Examples 1-5 and Example 6, the weight-average molecular weight (Mw) of pectin in Examples 1-5 was within the preferred range of 8.0*10^4 to 5.0*10^5 Da, while the weight-average molecular weight (Mw) of pectin in Example 6 was outside this range. This resulted in a lower overall evaluation score for the pectin gel in Example 6. This indicates that further controlling the weight-average molecular weight of pectin is more beneficial for obtaining pectin gels with higher textural stability, less oil exudation, and better taste. Similarly, the polymer dispersion index (PDI) of pectin is also similar, and will not be illustrated here.

[0082] Observing Examples 7-21, it can be seen that during the preparation of pectin gel, when the types of sugar alcohols include xylitol and maltitol (or sorbitol) and the proportions of each sugar alcohol are within a certain range, the prepared emulsion is more stable, the formed pectin gel has higher textural stability, better water retention and moisture resistance, and a higher overall evaluation score, indicating that the pectin gel is qualified. Furthermore, it can be found that when there are three types of sugar alcohols, the overall evaluation score is even higher. This indicates that having three types of sugar alcohols within a certain proportion range is more conducive to obtaining pectin gels with high textural stability, low water and oil separation, and good taste.

[0083] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit the scope of protection of this application. Although this application has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application, but such modifications or substitutions are all within the scope of protection of this application.

Claims

1. A pectin gel, comprising pectin and a fat-soluble substance; The pectin includes pectin; the weight-average molecular weight of the pectin ranges from 5.0*10^4 to 6.0*10^5 Da, and the polymer dispersion index is 1 to 6; In the pectin domains, HG > 30 mol%, RG-1 ≤ 35 mol%; HG is homogalacturonic acid polysaccharide, and RG-1 is rhamnuronic acid polysaccharide type I.

2. The pectin gel of claim 1, wherein: The pectin has a weight-average molecular weight range of 8.0*10^4 to 5.0*10^5 Da and a polymer dispersion index of 1 to 4.

3. The pectin gel of claim 1, wherein: In the pectin domains, HG = 40–90 mol%, RG-1 = 4–30 mol%.

4. The pectin gel of claim 1, wherein: The pectin gel also includes sugar alcohols, which include a first sugar alcohol and a second sugar alcohol; the first sugar alcohol includes xylitol; the second sugar alcohol includes at least one of maltitol and sorbitol. Alternatively, the sugar alcohol may include the first sugar alcohol, the second sugar alcohol, and the third sugar alcohol; the third sugar alcohol may include erythritol.

5. The pectin gel of claim 4, wherein: The sugar alcohol includes the first sugar alcohol and the second sugar alcohol, and the mass ratio of the first sugar alcohol to the second sugar alcohol is 1-30:0.09-65; Alternatively, the sugar alcohol may include the first sugar alcohol, the second sugar alcohol, and the third sugar alcohol, and the mass ratio of the first sugar alcohol, the second sugar alcohol, and the third sugar alcohol may be 1–30:0.09–65:0.1–10.

6. The pectin gel of claim 4, wherein: The mass ratio of the pectin, the sugar alcohol, and the fat-soluble substance is 0.5–5:10–70:5–50, calculated by mass ratio.

7. The pectin gel of claim 6 further comprises an emulsifier, wherein the mass ratio of the pectin, the sugar alcohol, the fat-soluble substance, and the emulsifier is 0.5–5:10–70:5–50:0.02–1.

8. The pectin gel of claim 1, wherein: The pectin accounts for 1-4% of the mass of the raw materials used in the preparation of the pectin gel.

9. The pectin gel of claim 7 further comprises an acidity regulator, wherein the mass ratio of the pectin to the acidity regulator is 0.5-5:0.5-7.

5.

10. A method for preparing pectin gel according to any one of claims 1 to 9, comprising the following steps: Aqueous phase preparation: The pectin, a portion of the sugar alcohol, and a portion of the acidity regulator are mixed evenly to obtain a gel premix; water, the remaining sugar alcohol, and deformed starch are mixed evenly, and the gel premix is ​​added to it and heated until completely dissolved to obtain the aqueous phase; Oil phase preparation: The fat-soluble substances are heated and mixed until the liquid is homogeneous to obtain the oil phase; Emulsification: The oil phase is added to the aqueous phase and mixed evenly, and then subjected to high-speed shear emulsification at 70-95°C to obtain an emulsion; Preparation: Mix the remaining acidity regulator and water at 70-80°C until completely dissolved, then add to the emulsion and mix for 5-10 minutes to obtain the liquid. Molding: Pour the liquid material onto the blister pack, then seal it, and let it stand for 40-60 hours to stabilize and form.

Images