Method for preparing eel fish bone meal by utilizing steam explosion
By processing eel bones through steam explosion technology, the problems of large particle size and low whiteness of fish bone powder were solved, efficient nutrient release and structural modification were achieved, and the functional properties and application potential of eel bone powder were improved.
Patent Information
- Application Number
- CN202511077920.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-01
- Publication Date
- 2025-09-19
AI Technical Summary
Existing technologies make it difficult to effectively crush eel bones, resulting in large particle size, low whiteness, and limited nutrient release of fish bone powder, which limits its application in the food industry.
Steam explosion technology is used to process eel bones. Through high-temperature and high-pressure steam penetration and instantaneous decompression, the fish bone tissue is destroyed and eel bone powder is prepared.
The whiteness, fineness and nutrient release efficiency of eel bone powder were significantly improved, a porous structure was formed, and its processing adaptability and functional properties were enhanced.
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Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of food processing, and particularly relates to a method for preparing eel bone powder by utilizing steam explosion. Background Art
[0002] As an important economic aquatic product, conger eels occupy a key position in the global aquatic product processing industry. The by-product fish bones produced during the processing account for about 10%-15% of the total raw materials. Most of them are currently discarded or used only as low-value feed raw materials, which not only causes waste of resources but also brings environmental pressure.
[0003] Fish bones are rich in mineral elements such as calcium and phosphorus, and are rich in collagen. They have high nutritional value and good development prospects. However, due to their hard texture and tightly interwoven collagen fibers, conventional processing methods are difficult to achieve structural deconstruction and effective degradation, further limiting their potential in the fields of nutritional supplements and functional foods. Traditional methods for preparing fish bone powder, such as steaming, high temperature and high pressure treatment, are difficult to effectively crush bone tissue due to mild treatment or a single method. The resulting fish bone powder has a large particle size, low whiteness, limited nutrient release, and poor bioavailability, which seriously restricts its in-depth development and application in the food industry.
[0004] Therefore, developing an efficient, green, and additive-free method for deconstructing fishbone tissue has become the key to improving its processing adaptability and functional quality. Summary of the Invention
[0005] Technical problems to be solved: In response to the above technical problems, the purpose of the present invention is to provide a method for preparing eel bone powder by steam explosion, which comprises the following steps: selecting fresh conger eel bones for raw material pretreatment, and then obtaining eel bone powder by enzymatic de-meat, steam explosion treatment, and drying and crushing, which belongs to the field of food processing technology. The present invention utilizes high-temperature and high-pressure steam to fully penetrate into the internal tissue of the fish bone, and then instantly reduces pressure and quickly releases the pressure to induce expansion of the fish bone tissue and cell rupture, thereby significantly improving the whiteness, fineness, solubility and nutrient release efficiency of the eel bone powder; and the eel bone powder prepared by the present invention exhibits a good loose porous structure, and shows significant antioxidant activity, and has excellent processing adaptability and multiple functional properties, which opens up a new way for the high-value utilization of fish bone by-product resources, and has important application value and broad market prospects.
[0006] Technical solution: A method for preparing eel bone powder by steam explosion, comprising the following steps: S1. Select fresh conger eel bones, remove impurities, clean and process conger eel bone segments with a length of 5-8cm; S2. The conger eel bone segments were mixed with water, and then alkaline protease was added for enzymatic hydrolysis. After the enzyme was inactivated, the conger eel bone segments were washed and dried to obtain pretreated conger eel bone segments; S3. Pre-treating the conger eel bone segments by steam explosion, collecting the solid-liquid mixture after the explosion and drying and crushing it to obtain eel bone powder.
[0007] Preferably, the material-liquid ratio of the conger eel bone segments to water in S2 is 1:(2-3).
[0008] Preferably, the enzymatic hydrolysis conditions in S2 are as follows: an enzymatic hydrolysis temperature of 50-60° C., an enzymatic hydrolysis time of 2-3 h, and an addition amount of alkaline protease of 2000-2500 U / g.
[0009] Preferably, the enzyme inactivation conditions in S2 are a treatment temperature of 90-100° C. and a treatment time of 10-15 min.
[0010] Preferably, the steam explosion treatment conditions in S3 are a pressure of 1.0-1.5 MPa and a steam explosion time of 3-15 min.
[0011] Preferably, the drying conditions in S3 are a drying temperature of 55-65° C. and a drying time of 8-12 h.
[0012] Preferably, the specific method of pulverizing in S3 is to use a high-speed pulverizer to pulverize for 2-5 minutes and pass through an 80-100 mesh sieve to obtain eel bone powder.
[0013] Eel bone meal prepared by any of the above methods.
[0014] Beneficial effects: 1. The present invention uses steam explosion technology to process conger eel bones to prepare conger eel bone powder. The eel bone tissue is filled with high-temperature and high-pressure steam, and then instantaneously released under reduced pressure, thereby inducing bone tissue expansion and cell rupture, significantly improving the whiteness, fineness, solubility and nutrient release efficiency of the fish bone powder; and exhibiting a good loose porous structure and significant antioxidant activity, with excellent processing adaptability and functional properties.
[0015] 2. The method of preparing conger eel bone meal using steam explosion technology in the present invention can not only improve the quality and function of conger eel bone meal, but also provide a new technical solution for the high-value utilization of fish bone by-product resources. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 The calcium content of the eel bone meal prepared in Example 1, Example 2 and Comparative Examples 1-3; Figure 2The particle size distribution of the eel bone powder prepared in Example 1, Example 2 and Comparative Examples 1-3, where A represents the average particle size and B represents the particle size distribution; Figure 3 The WHC and OHC of the eel bone meal prepared in Example 1, Example 2 and Comparative Examples 1-3; Figure 4 The XRD patterns of the eel bone powder prepared in Example 1, Example 2, and Comparative Examples 1-3 are shown; Figure 5 The scanning electron micrographs of the eel bone powder prepared in Example 1, Example 2, and Comparative Examples 1-3 are shown; Figure 6 Sensory radar charts of the eel bone meal prepared in Example 1, Example 2, and Comparative Examples 1-3; Figure 7 The protein digestibility of the eel bone meal prepared in Example 1, Example 2 and Comparative Examples 1-3; Figure 8 The ABTS free radical scavenging ability and DPPH free radical scavenging ability of the eel bone powder prepared in Example 1, Example 2 and Comparative Examples 1-3. DETAILED DESCRIPTION
[0017] The present invention will be further described below in conjunction with examples, which are provided to explain the present invention and are not limited to the following examples: Example 1
[0018] A method for preparing eel bone powder by steam explosion comprises the following steps: S1. Raw material pretreatment: Fresh conger eel bones were selected, viscera and soft tissue attached to the surface were removed, and the bones were washed and cut into 6 cm long segments to obtain conger eel bone segments; S2. Enzymatic deveining: 200 g of conger eel bone segments were mixed with 400 mL of water and enzymatically degraded with 2400 U / g of alkaline protease at 55°C for 3 h. After decomposition, the segments were inactivated by boiling in water at 95°C for 10 min. The segments were then rinsed and air-dried to obtain pretreated conger eel bone segments. S3. Steam explosion treatment: The pretreated conger eel bone segments were placed in a QBS-80 steam explosion apparatus and subjected to a pressure of 1.0 MPa for 15 min. The pressure was released immediately after the treatment, with the release time being less than 0.5 s, and the solid-liquid mixture was collected after the explosion. S4. Drying and pulverization: The solid-liquid mixture after steam explosion was dried at 60°C for 10 h; pulverized using a high-speed pulverizer for 2 min, and passed through a 100-mesh sieve to obtain eel bone powder, designated as SE-EBP. 1.0-15 . Example 2
[0019] A method for preparing eel bone powder by steam explosion comprises the following steps: S1. Raw material pretreatment: Fresh conger eel bones were selected, viscera and soft tissue attached to the surface were removed, and the bones were washed and cut into 6 cm long segments to obtain conger eel bone segments; S2. Enzymatic deveining: 200 g of conger eel bone segments were mixed with 400 mL of water and enzymatically degraded with 2400 U / g of alkaline protease at 55°C for 3 h. After decomposition, the segments were inactivated by boiling in water at 95°C for 10 min. The segments were then rinsed and air-dried to obtain pretreated conger eel bone segments. S3 steam explosion treatment: The pretreated conger eel bone segment was placed in a QBS-80 steam explosion device and treated at a pressure of 1.5MPa for 3min; the pressure was released instantly after the treatment, and the pressure release time was less than 0.5s, and the solid-liquid mixture after the explosion was collected; S4. Drying and pulverization: The solid-liquid mixture after steam explosion was dried at 60°C for 10 h; pulverized using a high-speed pulverizer for 2 min, and passed through a 100-mesh sieve to obtain eel bone powder, designated as SE-EBP. 1.5-3 . Comparative Example 1
[0020] A method for preparing native eel bone powder comprises the following steps: S1. Raw material pretreatment: Fresh conger eel bones were selected, viscera and soft tissue attached to the surface were removed, and the bones were washed and cut into 6 cm long segments to obtain conger eel bone segments; S2. Enzymatic deveining: 200 g of conger eel bone segments were mixed with 400 mL of water and enzymatically degraded with 2400 U / g of alkaline protease at 55°C for 3 h. After decomposition, the segments were inactivated by boiling in water at 95°C for 10 min. The segments were then rinsed and air-dried to obtain pretreated conger eel bone segments. S3. Drying and pulverizing: The pretreated conger eel bone segments were dried at 60°C for 10 h; pulverized using a high-speed grinder for 2 min, and passed through a 100-mesh sieve to obtain eel bone powder, which was designated as N-EBP. Comparative Example 2
[0021] A method for preparing steamed eel bone meal comprises the following steps: S1. Raw material pretreatment: Fresh conger eel bones were selected, viscera and soft tissue attached to the surface were removed, and the bones were washed and cut into 6 cm long segments to obtain conger eel bone segments; S2. Enzymatic deveining: 200 g of conger eel bone segments were mixed with 400 mL of water and enzymatically degraded with 2400 U / g of alkaline protease at 55°C for 3 h. After decomposition, the segments were inactivated by boiling in water at 95°C for 10 min. The segments were then rinsed and air-dried to obtain pretreated conger eel bone segments. S3. Steaming: Steam the pretreated conger eel bone segments in a steamer for 30 min; S4. Drying and pulverizing: The steamed conger eel bone segments were dried at 60°C for 10 h; pulverized using a high-speed grinder for 2 min, and passed through a 100-mesh sieve to obtain eel bone powder, designated as S-EBP. Comparative Example 3
[0022] A method for preparing high-temperature and high-pressure eel bone powder comprises the following steps: S1. Raw material pretreatment: Fresh conger eel bones were selected, viscera and soft tissue attached to the surface were removed, and the bones were washed and cut into 6 cm long segments to obtain conger eel bone segments; S2. Enzymatic deveining: 200 g of conger eel bone segments were mixed with 400 mL of water and enzymatically degraded with 2400 U / g of alkaline protease at 55°C for 3 h. After decomposition, the segments were inactivated by boiling in water at 95°C for 10 min. The segments were then rinsed and air-dried to obtain pretreated conger eel bone segments. S3. High-temperature and high-pressure treatment: Place the pretreated conger eel bone segments in an autoclave at 120°C and 0.1 MPa for 20 min. S4. Drying and pulverizing: The conger eel bone segments treated with high temperature and high pressure were dried at 60°C for 10 h; pulverized using a high-speed grinder for 2 min, and passed through a 100-mesh sieve to obtain eel bone powder, denoted as S-EBP.
[0023] Performance Testing (1) Whiteness Determination of eel bone powder using a colorimeter L*, a*, b* value. And through L*, a*, b* The whiteness of eel bone meal is calculated using the Hunter whiteness formula: .
[0024] Table 1 Whiteness of eel bone powder prepared in Example 1, Example 2 and Comparative Examples 1-3
[0025] Note: Different letters represent the same column p The difference was significant if <0.05.
[0026] As can be seen from Table 1, the eel bone powder prepared in Example 1 and Example 2 are significantly higher than those in Comparative Example 1 and Comparative Example 2, indicating that the whiteness of the eel bone powder under steam explosion treatment is significantly improved. This is mainly due to the strong shear force generated by high temperature, high pressure and rapid pressure release, which helps to break up the tissue structure and remove pigments. Although the partial hydrolysis of proteins and lipids during the steam explosion process may induce the Maillard reaction, the short treatment time avoids excessive browning. The overall effect is mainly to remove pigments and improve whiteness.
[0027] (2) Determination of basic nutrients The crude protein, crude fat and ash contents of eel bone meal were determined according to the methods specified in GB / T 5009.5-2016, GB / T 5009.6-2016 and GB / T 5009.4-2016.
[0028] Table 2 Basic nutritional content of eel bone meal prepared in Example 1, Example 2 and Comparative Examples 1-3 (dry weight %)
[0029] Note: Different letters represent the same column p The difference was significant if <0.05.
[0030] As can be seen from Table 2, the crude protein content of Example 1 and Example 2 is lower than that of Comparative Examples 1-3, the crude fat content is lower than that of Comparative Examples 1 and 3, and the crude ash content is significantly higher than that of Comparative Examples 1-3, indicating that steam explosion treatment significantly reduces the crude protein and crude fat contents, while significantly increasing the crude ash content. This is because steam explosion induces protein hydrolysis, small molecule volatilization and Maillard reaction, resulting in protein loss; fat is reduced due to hydrolysis, oxidation or steam dissipation; the increase in ash content is mainly due to the relative enrichment of minerals after the degradation of organic matter, and the increase in the proportion of stable inorganic components in fish bones, such as hydroxyapatite.
[0031] (3) Calcium content The calcium content of eel bone powder was determined using inductively coupled plasma optical emission spectrometry.
[0032] Depend on Figure 1 As can be seen, the calcium content of Examples 1 and 2 is significantly higher than that of Comparative Examples 1-3. This indicates that the present invention uses steam explosion treatment to prepare eel bone powder. Through high temperature and high pressure, instantaneous release, the structure of conger eel bones is rapidly destroyed, making the calcium salts in the bone tissue more easily released and dissolved. Steam explosion also creates a more intense physical impact in a short period of time, significantly increasing the degree of bone comminution and porosity, and enhancing the efficiency of calcium dissolution. In addition, this treatment method can also reduce the strength of calcium binding to the organic matrix, making calcium easier to extract and measure, resulting in a significantly higher calcium content than in Comparative Examples 1-3.
[0033] (4) Particle size The particle size and particle size distribution of eel bone powder were measured using a laser particle size distribution analyzer. The average particle size of the fish bone powder was determined using the median particle size (D 50） express.
[0034] Depend on Figure 2It can be seen that the particle size of the eel bone powder prepared in Example 1 and Example 2 is significantly smaller than that of the comparative examples 1-3, indicating that the steam explosion treatment significantly reduces the particle size of the eel bone powder. This is due to the synergistic effect of the hydrothermal dissociation and the cavitation and shear force caused by the instantaneous pressure release during the steam explosion process. The high-pressure steam penetrates the interior of the fish bone to weaken the organic-inorganic interface, loosen the collagen network, and the instantaneous pressure release causes the interface of the fish bone structure to peel off and undergo multi-stage crushing, thereby significantly reducing the particle size of the eel bone powder.
[0035] (5) Water and oil holding capacity Eel bone powder samples were added with distilled water and commercial soybean oil at a mass-to-volume ratio of 1:10, stirred at room temperature for 30 min, and then centrifuged at 3000 rpm for 10 min. The weight of the residue was used to calculate WHC and OHC.
[0036] Depend on Figure 3 As can be seen, the water and oil holding capacities of Examples 1 and 2 were significantly higher than those of Comparative Examples 1-3. This is because, under the conditions of high temperature, high pressure, and instantaneous pressure release, a large number of cracked surfaces and porous network structures are formed within the bone tissue, significantly enhancing the bone meal's ability to adsorb and physically bind water and oil. Furthermore, the ultrafine particle size and loose structure further expand the specific surface area, exposing more polar functional groups (such as -OH and -NH2) within the protein polypeptide segments, thereby enhancing their hydrophilic interactions with water molecules. Simultaneously, the intense shearing disrupts the cellular structure, exposing hydrophobic groups and promoting lipid oxidation to form lipophilic aldehydes and ketones, enhancing oil solubility. Furthermore, the eel bone meal prepared in the Examples is rich in amphiphilic molecules such as short-chain peptides and oxidized lipids, further enhancing its amphiphilic binding capacity for both aqueous and oil phases.
[0037] (6) XRD determination The XRD pattern of eel bone powder was measured using an X-ray diffractometer; the diffraction angle range was 5 to 70° (2θ), the step size was 0.02°, and the scanning speed was 4 μm / min. -1 .
[0038] Depend on Figure 4 It can be seen that both Example 1 and Example 2 have more, higher and more concentrated diffraction peaks, reflecting that the crystallinity of their hydroxyapatite crystal structures is significantly improved. This is because the synergistic effect of high temperature and high pressure and instantaneous pressure relief during the steam explosion process, on the one hand, destroys the encapsulation of hydroxyapatite crystals by organic matrices such as collagen, so that the crystal plane is fully exposed; on the other hand, it induces the dissolution-recrystallization process of hydroxyapatite microcrystals, eliminates lattice defects, and promotes crystal orientation growth.
[0039] (7) Scanning electron microscopy (SEM) The eel bone powder was evenly fixed on the silicon wafer of the sample stage, and then gold was sprayed to densify its surface, and the surface morphology of the eel bone powder was observed.
[0040] Depend on Figure 5 It can be seen that the surface of the eel bone powder in Examples 1 and 2 exhibits a distinct porous and loose structure, accompanied by cracks, holes, and fragmentation. This is mainly attributed to the shear force and internal stress generated by the instantaneous release of high-temperature and high-pressure steam during the steam explosion process, which causes the water inside the bone to rapidly vaporize and expand, thereby destroying the original organic-inorganic composite network and forming a porous skeleton. This is not only beneficial for particle size control, but also provides a structural basis for subsequent functional applications (such as solubility and adsorption).
[0041] (8) Sensory evaluation The sensory evaluation of eel bone meal samples was carried out using quantitative descriptive sensory analysis (QDA) method.
[0042] Depend on Figure 6 As can be seen, the comprehensive sensory evaluation results of Examples 1 and 2 were superior to those of Comparative Examples 1-3. This indicates that steam explosion treatment, through high temperature and high pressure, destroys the cellular structure of fish bones and tissues, releasing flavor precursors and significantly reducing residual fishy odors, thereby alleviating the fishy odor. Furthermore, this treatment may cause the pyrolysis of some lipids and proteins or the occurrence of Maillard reactions, generating volatile compounds with smoky or baked flavors, imparting unique flavor characteristics to the samples. Therefore, the eel bone meal prepared in these examples demonstrated the highest acceptance in the manual sensory evaluation.
[0043] (9) Protein digestibility The total nitrogen in the supernatant after in vitro simulated digestion of the samples was measured using the Kjeldahl method, and the in vitro digestibility of protein was estimated using the following formula: ; Where m1 is the protein content of the supernatant (mg), and m2 is the total protein content of eel bone meal (mg).
[0044] Depend on Figure 7 It can be seen that the protein digestibility of Examples 1 and 2 is significantly better than that of Comparative Examples 1-3, indicating that they are more susceptible to enzymatic hydrolysis; steam explosion unwinds the collagen triple helix into loose peptide chains, exposing more enzyme cleavage sites, and breaks peptide bonds through cavitation and shearing to generate low-molecular peptide fragments. At the same time, the interfacial exfoliation of minerals and proteins reduces the steric hindrance of enzyme action. In contrast, the structural destruction of Comparative Examples 1-3 was incomplete or protein reaggregation occurred; Examples 1 and 2 also have the advantages of small particle size and strong water solubility, which improves the enzyme contact efficiency and achieves overall synergistic optimization of structural deconstruction and functional improvement.
[0045] (10) Antioxidant capacity determination The antioxidant capacity of eel bone powder was determined using ABTS and DPPH kits.
[0046] Depend on Figure 8As can be seen, the ABTS and DPPH free radical scavenging abilities of Examples 1 and 2 were significantly higher than those of Comparative Examples 1-3, indicating that steam explosion treatment significantly enhanced the ABTS and DPPH free radical scavenging abilities of eel bone meal, releasing more active ingredients such as peptides, amino acids, and trace minerals. These active substances have strong electron donor abilities, effectively neutralizing free radicals and enhancing antioxidant activity. Therefore, steam explosion technology not only accelerates the release of active ingredients but also enhances the antioxidant potential of eel bone meal through structural modification.
[0047] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any person skilled in the art can, without departing from the spirit and technical solution of the present invention, use the methods and technical contents disclosed above to make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent embodiment with equivalent changes. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of protection of the technical solution of the present invention.
Claims
1. A method for preparing eel bone powder by steam explosion, characterized in that: The following steps are involved: S1. Select fresh conger eel bones, remove impurities, clean and process conger eel bone segments with a length of 5-8cm; S2. The conger eel bone segments were mixed with water, and then alkaline protease was added for enzymatic hydrolysis. After the enzyme was inactivated, the conger eel bone segments were washed and dried to obtain pretreated conger eel bone segments; S3. Pre-treating the conger eel bone segments by steam explosion, collecting the solid-liquid mixture after the explosion and drying and crushing it to obtain eel bone powder.
2. The method for preparing eel bone powder by steam explosion according to claim 1, characterized in that: The material-liquid ratio of the conger eel bone segment to water in S2 is 1:(2-3).
3. The method for preparing eel bone powder by steam explosion according to claim 1, characterized in that: The enzymatic hydrolysis conditions in S2 are as follows: an enzymatic hydrolysis temperature of 50-60° C., an enzymatic hydrolysis time of 2-3 h, and an addition amount of alkaline protease of 2000-2500 U / g.
4. The method for preparing eel bone powder by steam explosion according to claim 1, wherein: The conditions for inactivating the enzyme in S2 are a treatment temperature of 90-100° C. and a treatment time of 10-15 minutes.
5. The method for preparing eel bone powder by steam explosion according to claim 1, characterized in that: The steam explosion treatment conditions in S3 are a pressure of 1.0-1.5 MPa and a steam explosion time of 3-15 min.
6. The method for preparing eel bone powder by steam explosion according to claim 1, characterized in that: The drying conditions in S3 are a drying temperature of 55-65° C. and a drying time of 8-12 h.
7. The method for preparing eel bone powder by steam explosion according to claim 1, characterized in that: The specific method of the pulverization in S3 is to use a high-speed pulverizer to pulverize for 2-5 minutes and pass through an 80-100 mesh sieve to obtain eel bone powder.
8. Eel fish bone meal prepared according to the method according to any one of claims 1 to 7.