Method for preparing high oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation
By treating rice bran dietary fiber with steam explosion and probiotic fermentation, the problems of low oil retention and poor flavor caused by the dense structure of rice bran dietary fiber were solved, and the preparation of rice bran dietary fiber with high oil absorption performance was achieved, which enhanced its application potential in special population foods.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- WUYI UNIV
- Filing Date
- 2025-07-15
- Publication Date
- 2026-06-12
AI Technical Summary
Rice bran dietary fiber has a dense structure that results in low oil holding capacity and poor flavor, which limits its application in the food industry.
The process employs a combination of steam explosion and probiotic fermentation technology, including rice bran powder crushing, acetic acid soaking, steam explosion, probiotic fermentation, and drying, which breaks down the dense structure of rice bran dietary fiber, enhances its oil-holding capacity, and improves its flavor.
It significantly improves the oil retention and flavor of rice bran dietary fiber, enhancing its application value in foods for special populations.
Smart Images
Figure CN120678233B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of food processing technology, specifically relating to a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation. Background Technology
[0002] Dietary fiber (DF) is one of the seven essential nutrients for humans. It is composed of cellulose, hemicellulose, lignin, and pectin-like substances, containing numerous active groups such as carboxyl, hydroxyl, and amide groups. These groups endow it with certain water-holding capacity, oil-holding capacity, adsorption capacity, and cation exchange capacity, thus offering benefits such as lowering cholesterol, regulating blood sugar, increasing stool volume, stimulating intestinal peristalsis, and improving constipation. It can be used to prevent chronic diseases such as obesity and diabetes. Rice bran, a byproduct of rice processing, is rich in dietary fiber, accounting for approximately 30% of its weight. However, rice bran dietary fiber is tightly bound together with starch, polyphenols, and other substances, resulting in insufficient exposure of active groups such as hydroxyl and carboxyl groups, thereby limiting its functional properties. Furthermore, rice bran dietary fiber has a rough texture, poor flavor, and poor solubility, restricting its application in the food industry. Therefore, modifying rice bran dietary fiber using modification techniques to enhance its functional properties has become a research hotspot.
[0003] Currently, the main methods for modifying dietary fiber include physical, chemical, biological, and combined methods. Single physical or biological methods for modifying dietary fiber have limitations in enhancing its functionality. Combined methods for modifying dietary fiber have attracted the attention of researchers. Steam explosion is a green physical processing technology that has become popular in recent years, characterized by high efficiency and environmental friendliness. Currently, there is very little research on modifying dietary fiber using a combination of steam explosion and fermentation processing technologies. This invention significantly improves the oil absorption performance of rice bran dietary fiber and enhances its flavor by using steam explosion combined with probiotic fermentation technology. It overcomes the technical challenge of poor oil absorption due to the dense structure of rice bran dietary fiber, providing a new technical approach for the application of rice bran powder in special foods for diabetic or obese patients. This invention is of great significance for guiding the food utilization of rice bran. Summary of the Invention
[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation, thereby solving the problem of low oil holding capacity and poor flavor caused by the dense structure of rice bran dietary fiber. This provides dietary fiber ingredients for foods specifically for obese or diabetic patients, and helps to increase the added value of rice bran.
[0005] This invention also proposes a method for preparing highly oil-absorbing dietary fiber.
[0006] The present invention also proposes an application.
[0007] According to a first aspect of the present invention, a method for preparing highly oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation is provided, the method comprising the following steps:
[0008] S1: Soak rice bran powder in an aqueous acetic acid solution, filter and dry to obtain dried rice bran powder;
[0009] S2: The dried rice bran powder obtained in step S1 is subjected to steam explosion processing to obtain steam-exploded rice bran powder.
[0010] S3: Add water, prebiotics and probiotics to the rice bran powder obtained after steam explosion in step S2 for fermentation. After fermentation, filter and collect the residue, which is the high oil-absorbing dietary fiber.
[0011] The more specific steps are as follows:
[0012] S1-1. Rice bran crushing: Crush the rice bran to reduce the particle size of the rice bran powder and pass it through a 120-mesh sieve.
[0013] Reducing the particle size is beneficial in two ways: firstly, it facilitates the acid hydrolysis reaction between the dietary fiber in rice bran powder and the acetic acid in step S2; secondly, it helps the steam explosion processing in step S3 to break down the dense dietary fiber structure in rice bran and improve its oil-holding capacity.
[0014] S1-2. Acetic acid soaking: Add an aqueous acetic acid solution to the rice bran powder obtained in step S1-1, stir at room temperature, and then filter. Dry the soaked rice bran powder with hot air while maintaining a suitable moisture content.
[0015] Acetic acid soaking can partially hydrolyze the hemicellulose in rice bran, disrupting the cellulose-hemicellulose-lignin complex structure, reducing cellulose crystallinity, softening the cell wall structure of rice bran, initially destroying its dense structure, and increasing the porosity of rice bran fibers. This creates favorable conditions for steam explosion processing in step S2: high-pressure steam can more easily penetrate the loose structure, and the mechanical tearing effect during explosion is enhanced. Furthermore, moisture, as the sole medium in the steam explosion processing, acts as a heat transfer medium, buffer, reactant, and dissolving agent, affecting the swelling of rice bran materials and the penetration of steam, thereby influencing the structure of chemical components in rice bran, such as dietary fiber and starch macromolecules. Therefore, it is necessary to control the moisture content of the dried rice bran powder, as it is closely related to the explosion effect.
[0016] S2. Steam explosion processing: The dried rice bran powder obtained in step S1 is subjected to steam explosion processing.
[0017] Steam explosion processing is a green and efficient food processing technology, serving two purposes in this invention: First, it matures the rice bran powder and gelatinizes the starch. Some of the starch degrades into reducing sugars after steam explosion, providing a carbon source for probiotic fermentation in step S3. Second, steam explosion can disrupt the dense spatial structure of rice bran dietary fiber, enhancing its oil-holding capacity. Rice bran contains a dense structure of dietary fiber, primarily insoluble (approximately 90%), with a low content of soluble dietary fiber, resulting in poor oil-holding capacity. During steam explosion processing, the rice bran powder is subjected to high temperature and pressure. Opening the valve of the explosion machine causes a sudden pressure drop, instantly evaporating moisture from the pores of the dietary fiber. This loosens the dense structure of the dietary fiber, enhancing its oil-holding capacity.
[0018] S3-1. Probiotic fermentation: Add purified water and prebiotics to the rice bran powder after steam explosion in step S2, and inoculate with probiotics for liquid anaerobic fermentation.
[0019] Probiotic fermentation utilizes the sugars and proteins intertwined with the dietary fiber in rice bran, producing β-glucosidase and ferulic acid esterase. This causes the polysaccharides and polyphenols linked to the dietary fiber to dissociate, further loosening the fiber's structure and enhancing its oil-holding capacity. In addition, probiotic fermentation also imparts a pleasant flavor to the rice bran dietary fiber. However, not all probiotics are suitable for the anaerobic fermentation of rice bran; scientific experiments are needed to determine the strains best suited for this process.
[0020] S3-2. Drying the finished product: Filter the fermented rice bran liquid obtained in step S3-1 to remove soluble polysaccharides, proteins and polyphenols. The residue is mainly dietary fiber. Dry it in an oven to obtain dietary fiber powder with high oil absorption properties.
[0021] In step S1-1, after crushing and sieving, the rice bran powder has a particle size of less than 125μm.
[0022] In steps S1-2, the concentration of the acetic acid aqueous solution is 1-3% (by volume percentage), the amount added is 2-4 times the weight of the rice bran powder, the soaking time is 20-60 minutes, and the stirring speed is 600-1200 rpm. The drying temperature is 40℃-50℃, and the moisture content of the dried rice bran powder is 30%-35%.
[0023] In step S2, the filling rate of rice bran powder in the steam explosion cylinder is 15% to 25%. When the pressure in the steam explosion cylinder reaches 0.8 to 1.2 MPa, the pressure is maintained for 20 to 50 seconds, and then the valve is opened to release the pressure instantly, and the rice bran powder after steam explosion processing is collected.
[0024] In step S3-1, the fermentation strain used is a complex of *Bifidobacterium longum* and *Bifidobacterium adolescentis*, with a 1:1 ratio of the two strains. Inoculation and fermentation are carried out when the viable cell count in the culture medium reaches 81 g CFU / mL or higher. The amount of strain added is 1-5% of the rice bran powder (dry basis). The amount of purified water added is 4-8 times the weight of the rice bran. The added prebiotics are human milk oligosaccharides and long-chain inulin (degree of polymerization ≥ 10); based on the weight of the rice bran powder, the amount of human milk oligosaccharides added is 0.2%-0.8%, and the amount of long-chain inulin added is 0.5%-1%. The fermentation temperature is 35℃-39℃, and the fermentation time is 24-36 hours. After fermentation, compared to the rice bran powder before grinding, its oil-holding capacity increases by 80%-120%. Before grinding, rice bran powder consists of small, dense particles of varying sizes. After steam explosion, the edges of these particles are torn, becoming fuzzy and revealing flaky dietary fiber structures. Further fermentation completely destroys the dense structure of the rice bran particles, transforming them into a loose, porous network with numerous pores, which facilitates oil encapsulation. This invention explains the increased oil-holding capacity of processed rice bran dietary fiber from the perspective of microstructural changes. Based on this principle, a steam explosion combined with probiotic fermentation technology was developed to prepare rice bran dietary fiber with high oil absorption properties.
[0025] The drying process conditions in step S3-2 are as follows: the drying temperature is 40℃~50℃ and the drying time is 8~15h.
[0026] Compared with the prior art, the present invention has at least the following beneficial effects:
[0027] This invention uses rice bran as raw material, pre-treating it with acetic acid soaking, and then processing it through steam explosion combined with probiotic fermentation to prepare dietary fiber with high oil absorption capacity and a loose, porous structure. This fiber can be used as a food ingredient in the research and development of special foods for obese patients or diabetics. The method of preparing high oil-absorbing dietary fiber through steam explosion combined with probiotic fermentation provided by this invention not only improves the oil-holding capacity of rice bran dietary fiber powder but also enhances its flavor, significantly increasing the added value of rice bran. Attached Figure Description
[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:
[0029] Figure 1 The images shown are scanning electron microscope (SEM) results from Example 1 of this invention; where A represents rice bran before pulverization (scale bar 50 μm), B represents rice bran powder after steam explosion processing (scale bar 10 μm), and C and D represent rice bran powder after probiotic fermentation (scale bar 10 μm). Detailed Implementation
[0030] The following will describe the concept and technical effects of the present invention clearly and completely with reference to embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.
[0031] Unless otherwise specified, the instruments and reagents used in the following examples are those that can be obtained through conventional purchasing channels.
[0032] Example 1
[0033] This embodiment provides a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation, which specifically includes the following steps:
[0034] (1) Pulverizing rice bran: Put 1 kg of rice bran into a grinder for pulverizing. After pulverizing, pass it through a 120-mesh sieve to obtain rice bran powder with a particle size of less than 125 μm.
[0035] (2) Acetic acid soaking: Add 4 kg of 3% (v / v) acetic acid aqueous solution to the rice bran powder obtained in step (1) while stirring at a speed of 600 rpm. After stirring and soaking for 20 min, filter and discard the filtrate. Dry the soaked rice bran powder at 40℃ for 14 h (8-20 h is acceptable). The moisture content of the dried rice bran powder is 30%.
[0036] (3) Steam explosion processing: The dried rice bran powder in step (2) is put into the steam explosion equipment for processing. The filling rate of rice bran powder in the steam explosion cylinder is 15%. When the pressure in the steam explosion cylinder reaches 0.8MPa, the pressure is maintained for 20 seconds, and then the valve is opened to release the pressure instantly and collect the rice bran powder after steam explosion processing.
[0037] (4) Probiotic fermentation: Add 4 kg of purified water to the rice bran powder processed by steam explosion in step (3), add prebiotics (2 g of human milk oligosaccharide and 5 g of long-chain inulin (degree of polymerization DP≥10)), stir evenly, and inoculate with Bifidobacterium longum and Bifidobacterium adolescentis (mixed inoculation at a ratio of 1:1) for anaerobic fermentation. The inoculation amount is 1% of the weight of the rice bran powder obtained in step (1), the fermentation temperature is 37℃, and the fermentation time is 24 h.
[0038] (5) Drying the finished product: Filter the rice bran fermentation liquid obtained in step (4), and put the residue into an oven to dry at a temperature of 40°C for 15 hours. After drying, rice bran dietary fiber with good oil absorption properties is obtained.
[0039] The microstructure of rice bran before pulverization in step (1), rice bran powder after steam explosion processing in step (3), and rice bran powder after fermentation in step (4) were characterized using scanning electron microscopy. The results are as follows: Figure 1 As shown.
[0040] Depend on Figure 1 It can be seen that the rice bran powder before grinding consists of fine particles of varying sizes with a dense structure. Figure 1 A) After being steam-exploded, the edges of the rice bran particles are torn, and a fuzzy texture appears at the edges, revealing flaky dietary fiber structures. Figure 1 B), after further fermentation, the tight structure of the rice bran powder particles is completely destroyed, presenting a loose and porous network structure with numerous cavities, which is conducive to encapsulating oils (B). Figure 1 C and Figure 1 D).
[0041] Example 2
[0042] This embodiment provides a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation, which specifically includes the following steps:
[0043] (1) Pulverizing rice bran: Put 2 kg of rice bran into a grinder for pulverizing. After pulverizing, pass it through a 120-mesh sieve to obtain rice bran powder with a particle size of less than 125 μm.
[0044] (2) Acetic acid soaking: Add 4 kg of 1% acetic acid aqueous solution to the rice bran powder obtained in step (1) while stirring at a speed of 1200 rpm. After soaking for 60 min, filter and discard the filtrate. Dry the soaked rice bran powder at 50℃. The moisture content of the dried rice bran powder is 35%.
[0045] (3) Steam explosion processing: The dried rice bran powder in step (2) is put into the steam explosion equipment for processing. The filling rate of rice bran powder in the steam explosion cylinder is 25%. When the pressure in the steam explosion cylinder reaches 1.2MPa, the pressure is maintained for 50 seconds, and then the valve is opened to release the pressure instantly and collect the rice bran powder after steam explosion processing.
[0046] (4) Probiotic fermentation: Add 16 kg of purified water to the rice bran powder processed by steam explosion in step (3), add prebiotics (16 g of human milk oligosaccharide and 20 g of long-chain inulin), stir evenly, and inoculate with Bifidobacterium longum and Bifidobacterium adolescentis (mixed in a 1:1 ratio) for anaerobic fermentation. The inoculation amount is 5% of the weight of the rice bran powder obtained in step (1), the fermentation temperature is 37℃, and the fermentation time is 36 h.
[0047] (5) Drying the finished product: Filter the rice bran fermentation liquid obtained in step (4), and put the residue into an oven to dry at a temperature of 50°C for 8 hours. After drying, rice bran dietary fiber with good oil absorption properties is obtained.
[0048] Comparative Example 1
[0049] This comparative example demonstrates a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation. The only difference between this method and Example 1 is that step (2) is omitted, while the other steps and parameters are consistent with those of Example 1.
[0050] Comparative Example 2
[0051] This comparative example demonstrates a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation. The only difference between this method and Example 1 is that the moisture content of the dried rice bran powder in step (2) is controlled at 8%, while the other steps and parameters are consistent with Example 1.
[0052] Comparative Example 3
[0053] This comparative example demonstrates a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation. The only difference between this method and Example 1 is that step (3) is omitted, while the other steps and parameters are consistent with those of Example 1.
[0054] Comparative Example 4
[0055] This comparative example demonstrates a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation. The only difference between this method and Example 1 is that the pressure of steam explosion processing in step (3) is adjusted to 0.4 MPa, while the other steps and parameters are the same as in Example 1.
[0056] Comparative Example 5
[0057] This comparative example demonstrates a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation. The only difference between this method and Example 1 is that step (4) is omitted, while the other steps and parameters are consistent with those of Example 1.
[0058] Comparative Example 6
[0059] This comparative example demonstrates a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation. The only difference between this method and Example 1 is that the addition of human milk oligosaccharides and long-chain inulin in step (4) is omitted. All other steps and parameters are consistent with Example 1.
[0060] Comparative Example 7
[0061] This comparative example demonstrates a method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation. The only difference between this method and Example 1 is that the human milk oligosaccharides and long-chain inulin in step (4) are replaced with 5g of short-chain inulin (degree of polymerization of 2-10). All other steps and parameters are the same as in Example 1.
[0062] Test case
[0063] This experiment tested the oil-holding capacity of rice bran dietary fiber prepared in Examples 1-2 and Comparative Examples 1-7, and rice bran powder obtained only through crushing and sieving. The specific experimental methods and results are as follows:
[0064] The oil-holding capacity of rice bran powder, rice bran dietary fiber prepared in Examples 1-2 and Comparative Examples 1-7 was tested according to the detection method described in the literature "The Influence of Fermentation of Edible Fungi on the Structure and Functional Properties of Ginseng Insoluble Dietary Fiber" (Zhao Yunan, et al. Food Science, 2023, 44(22)80-88). The results are shown in Table 1.
[0065] Table 1. Oil-holding capacity of rice bran powder and rice bran dietary fiber
[0066]
[0067] Note: Different letters in the same column indicate significant differences between the values (p<0.05).
[0068] As shown in Table 1:
[0069] 1) The oil holding capacity of rice bran powder is 3.01 g / g, which is relatively low compared to Examples 1 and 2. The oil holding capacity of rice bran dietary fiber prepared in Examples 1 and 2 is 6.32 and 6.51 g / g, respectively, which are 110.0% and 116.3% higher than that of rice bran powder.
[0070] 2) Compared with Example 1, the rice bran dietary fiber of Comparative Example 1 was not treated with acetic acid soaking, but the other steps were the same as in Example 1. The oil holding capacity of the obtained rice bran dietary fiber was 4.03 g / g. The oil holding capacity of the rice bran dietary fiber prepared in Comparative Example 1 decreased by 36.2% compared with Example 1. This result indicates that the acetic acid soaking process plays an important role in enhancing the oil holding capacity of rice bran dietary fiber.
[0071] 3) The oil holding capacity of the rice bran dietary fiber prepared in Comparative Example 2 was 4.53 g / g, which was 28.3% lower than that in Example 1. This result indicates that the moisture content of the rice bran powder must be controlled at 30-35% in step (2) of Example 1. Too low a moisture content is not conducive to improving the oil holding capacity of the rice bran dietary fiber.
[0072] 4) The results of Comparative Example 3 show that if the steam explosion processing is not performed in the method provided by the present invention, the oil holding capacity of the prepared dietary fiber will be greatly reduced; compared with Example 1, the oil holding capacity of Comparative Example 3 decreased by 42.3%, and steam explosion processing played an important role in improving the oil holding capacity of rice bran dietary fiber.
[0073] 5) The results of Comparative Example 4 show that too low a steam explosion pressure will affect the oil holding capacity of the obtained rice bran dietary fiber.
[0074] 6) The results of Comparative Example 5 showed that fermentation of the compound probiotics composed of Bifidobacterium longum and Bifidobacterium adolescentis could significantly improve the oil retention capacity of rice bran dietary fiber.
[0075] 7) The results of Comparative Example 6 show that the two prebiotics selected in Example 1 of the present invention can better promote probiotic fermentation. The omission of these prebiotics is not conducive to probiotic fermentation, which leads to a decrease in the oil-holding capacity of rice bran dietary fiber.
[0076] 8) The results of Comparative Example 7 show that the prebiotic combination selected in Example 1 of the present invention can promote probiotic fermentation much better than short-chain inulin.
[0077] In summary, this invention prepares rice bran dietary fiber with high oil absorption capacity through processes such as acetic acid soaking, steam explosion, probiotic fermentation, and drying. This is a complete technological process. Removing any step or changing the prebiotic will reduce the effectiveness of this technology in enhancing the oil-holding capacity of the dietary fiber. The dietary fiber prepared by this invention has excellent oil absorption capacity and can be used in the preparation of special foods for specific populations such as diabetics and obese patients.
[0078] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.
Claims
1. A method for preparing highly oil-absorbing dietary fiber using steam explosion combined with probiotic fermentation, characterized in that, The method includes the following steps: S1: Soak rice bran powder in an acetic acid aqueous solution, filter, and then dry to obtain dried rice bran powder; the volume percentage of acetic acid in the acetic acid aqueous solution is 1-3%; the amount of acetic acid aqueous solution used is 2-4 times the weight of the rice bran powder before soaking; the soaking time is 20-60 min; the moisture content of the dried rice bran powder is 30%-35%; the rice bran powder is passed through a 120-mesh sieve before soaking; S2: The dried rice bran powder obtained in step S1 is subjected to steam explosion processing to obtain steam-exploded rice bran powder; the pressure of the steam explosion processing is 0.8~1.2 MPa; the pressure is maintained for 20~50 seconds during the steam explosion processing. S3: Add water, prebiotics, and probiotics to the steam-exploded rice bran powder obtained in step S2 for fermentation. After fermentation, filter and collect the residue, which is the high-oil-absorbing dietary fiber. The prebiotics include human milk oligosaccharides and long-chain inulin. The amount of human milk oligosaccharides added is 0.2% to 0.8% of the dry weight of the rice bran powder before soaking in step S1. The amount of long-chain inulin added is 0.5% to 1% of the dry weight of the rice bran powder before soaking in step S1. The probiotics are a compound of Bifidobacterium longum and Bifidobacterium adolescentis in a 1:1 ratio. The inoculum amount of probiotics is 1% to 5% of the dry weight of the rice bran powder before soaking in step S1. The fermentation temperature is 35℃ to 39℃. The fermentation time is 24 to 36 hours.
2. The method for preparing highly oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation according to claim 1, characterized in that, The soaking described in step S1 is performed under stirring conditions, with the stirring speed being 600~1200 rpm.
3. The method for preparing highly oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation according to claim 2, characterized in that, The drying temperature in step S1 is 40℃~50℃.
4. The method for preparing highly oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation according to claim 1, characterized in that, In step S2, the filling rate of the dried rice bran powder in the steam explosion cylinder during the steam explosion process is 15% to 25%.
5. The method for preparing highly oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation according to claim 1, characterized in that, The amount of water added in step S3 is 4 to 8 times the dry weight of the rice bran powder before soaking in step S1.
6. The method for preparing highly oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation according to claim 1, characterized in that, Step S3 further includes drying the filter residue after filtration.
7. The method for preparing highly oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation according to claim 6, characterized in that, The drying temperature is 40℃~50℃.
8. The method for preparing highly oil-absorbing dietary fiber by steam explosion combined with probiotic fermentation according to claim 6, characterized in that, The drying time is 8-15 hours.
9. The high oil-absorbing dietary fiber prepared by the method of steam explosion combined with probiotic fermentation as described in any one of claims 1 to 8.