Method for producing fish sauce from smelly mandarin fish leftovers

Abstract

The invention discloses a method for producing fish sauce from smelly mandarin fish leftovers, and belongs to the technical field of reutilization of fish product processing byproducts. The method comprises the following steps: obtaining hydrolytic peptide obtained after enzymolysis of a smelly mandarin fish byproduct as a main raw material; the compound aspergillus protease is prepared by adopting a starter propagation process and comprises aspergillus oryzae, aspergillus niger and monascus in a mass ratio of 3: 2: 1; according to the method, domesticated mixed aspergillus protease is used as a fermentation strain, a raw material mainly containing hydrolyzed peptide obtained after enzymolysis of the siniperca chuatsi by-products is subjected to fermentation treatment, salt accounting for 8%-18% of the mass of homogenate is added during fermentation treatment, and the fermentation temperature is 30-34 DEG C. According to the method, monascus, aspergillus oryzae, aspergillus niger and the like are screened as fermentation strains, and technological parameters such as the aspergillus compounding proportion, the aspergillus addition amount, the fermentation time, the salt concentration, the fermentation temperature and the like are optimized, so that a controllable fish sauce fermentation mode can be effectively constructed, and the taste and the quality of the obtained fish sauce product are ensured.

Description

Technical Field

[0001] This invention belongs to the field of fish product processing by-product recycling technology, and more specifically, relates to a method for producing fish sauce from stinky mandarin fish by-products. Background Technology

[0002] The processing of stinky mandarin fish generates a large amount of byproducts, accounting for approximately 40% to 55% of the fish's weight. In Huangshan, Anhui Province alone, stinky mandarin fish processing enterprises generate nearly 20,000 tons of byproducts annually. Currently, the main processing methods at these plants are processing them into animal feed or discarding them directly. These methods not only waste resources and pollute the environment but also significantly reduce the utilization rate of the byproducts.

[0003] Fish sauce is extremely rich in nutrients, containing various natural antioxidants that can reduce free radical damage to the human body and have anti-cancer and cancer-preventive effects, with efficacy more than ten times higher than ordinary antioxidants. In addition to containing the eight essential amino acids required by the human body, fish sauce also contains various minerals and trace elements such as calcium and iodine. Preparing polypeptides from protein hydrolysates of fermented mandarin fish byproducts and establishing key technologies for rapid fish sauce brewing will help improve the high-value utilization and environmental protection capabilities of byproducts in the fermented mandarin fish industry. This can effectively promote the technological innovation of modern industrialization in the fermented mandarin fish industry and achieve sustainable and green development. Summary of the Invention

[0004] This invention provides a method for producing fish sauce from the by-products of stinky mandarin fish. The method uses hydrolyzed peptides obtained from the enzymatic hydrolysis of stinky mandarin fish by-products as the main raw material and employs a koji-making fermentation method to rapidly brew fish soy sauce seasoning products. By screening Monascus purpureus, Aspergillus oryzae, and Aspergillus niger as fermentation strains and optimizing process parameters such as the ratio of Aspergillus compound, the amount of Aspergillus added, fermentation time, salt concentration, and fermentation temperature, a controllable fish sauce fermentation mode can be effectively constructed.

[0005] To achieve the above objectives, the technical solution provided by the present invention is as follows: This invention provides a method for producing fish sauce from mandarin fish by-products, comprising: Hydrolyzed peptides obtained from the enzymatic hydrolysis of stinky mandarin fish by-products are used as the main raw materials, wherein the degree of hydrolysis of the stinky mandarin fish by-products is 18%~22%; A compound Aspergillus protease was prepared using a koji-making process. The compound Aspergillus protease included Aspergillus oryzae, Aspergillus niger and Aspergillus rubrum, with a mass ratio of 3:2:1 for the three enzymes. A well-domesticated mixed Aspergillus protease was used as the fermentation strain to ferment raw materials mainly composed of hydrolyzed peptides from the enzymatic hydrolysis of mandarin fish by-products. During the fermentation process, 8% to 18% salt by weight of the homogenate was added, and the fermentation temperature was 30 to 34°C.

[0006] This invention uses a mixture of Aspergillus oryzae, Aspergillus niger, and Monascus purpureus as fermentation strains and strictly controls the mass ratio of the three strains. This allows for efficient protein degradation, increased yield, balanced flavor and aroma, and effective decomposition of the complex components of fermented mandarin fish by-products, thus preventing oxidative rancidity and off-odors.

[0007] Enzymatic hydrolysis before fermentation can accelerate the fermentation process, but while shortening the fermentation cycle, attention should also be paid to the fermented flavor. A higher degree of enzymatic hydrolysis results in a stronger bitter taste, which in turn affects the flavor of the fermented product. This invention controls the degree of hydrolysis of the byproducts of fermented mandarin fish, thereby not only shortening the fermentation cycle but also increasing the amino acid nitrogen content in the resulting fish sauce product while ensuring its taste.

[0008] The method for producing fish sauce from mandarin fish by-products according to the present invention is further preferably wherein 10% salt by mass of the homogenate is added to the fermentation raw materials during the fermentation process, and the fermentation temperature is 32°C.

[0009] More preferably, the degree of hydrolysis of the stinky mandarin fish by-product is 20%.

[0010] According to the method for producing fish sauce from mandarin fish by-products of the present invention, the amount of domesticated mixed Aspergillus protease added is 0.4% to 0.8% of the homogenate mass, more preferably 0.6%. The amount of starter culture added directly affects the fermentation. If the amount of starter culture added is too small, the microbial reproduction will be slow, resulting in a longer total fermentation cycle; if the amount of starter culture added is too large, it will result in energy waste and increase production costs.

[0011] According to the method for producing fish sauce from mandarin fish by-products of the present invention, the method uses domesticated compound Aspergillus protease as a fermentation strain to ferment raw materials mainly composed of hydrolyzed peptides obtained from the enzymatic hydrolysis of mandarin fish by-products. Specifically, the method includes: using hydrolyzed peptides obtained from the enzymatic hydrolysis of mandarin fish by-products as the main raw material, cooking to inactivate the enzyme and cooling to room temperature, adding salt, and inoculating with domesticated mixed Aspergillus protease, followed by fermentation to obtain fish sauce.

[0012] According to the method for producing fish sauce from mandarin fish by-products of the present invention, the koji-making process is specifically as follows: after mixing soybean meal: wheat bran: water in a mass ratio of (50~60):(40~50):(50~70), the mixture is subjected to high-pressure sterilization and then cooled to room temperature. Then, Aspergillus oryzae, Aspergillus niger and Aspergillus rubrum are inoculated and cultured to prepare each Aspergillus species.

[0013] According to the method for producing fish sauce from mandarin fish by-products of the present invention, the process parameters of the koji-making process include: koji-making temperature of 25℃~30℃, koji-making time of 3~4 days, and inoculation amount of each Aspergillus mold of 0.4%~1.2%; more preferably, the koji-making temperature is 28℃, the koji-making time is 4 days, and the inoculation amount of each Aspergillus mold is 0.8%. By optimizing the koji-making temperature and the inoculation amount of Aspergillus during the koji-making process, the number of koji spores can be increased and the enzyme activity can be improved. As the cultivation time increases, both enzyme activity and spore number increase rapidly. When the cultivation reaches the 4th day, the enzyme activity reaches its maximum, while the spore number remains basically unchanged. Therefore, the optimal cultivation time is determined to be 4 days.

[0014] According to the method for producing fish sauce from mandarin fish by-products of the present invention, the high-pressure sterilization treatment is performed under high-pressure sterilization conditions of 0.1~0.3MPa and 120~125℃ for 20~30 min.

[0015] Compared with the prior art, the technical solution provided by this invention has the following advantages: (1) This invention uses hydrolyzed peptides from the enzymatic hydrolysis of stinky mandarin fish by-products as the main raw material. By screening red mold, oryzae mold, and black mold as fermentation strains, and optimizing process parameters such as the ratio of Aspergillus compound, the amount of Aspergillus added, fermentation time, salt concentration, and fermentation temperature, fish soy sauce seasoning products can be quickly brewed through koji fermentation, realizing the high-value utilization of stinky mandarin fish by-products, and ensuring the total acid and amino acid nitrogen content of the obtained fish sauce products.

[0016] (2) By optimizing the design of various process parameters of the koji-making process, this invention can ensure that the koji-making enzyme activity is high, the number of spores is large, and the two are well coordinated.

[0017] (3) By optimizing the design of various process parameters of the fermentation process, the present invention can effectively ensure the amino acid nitrogen content and total acid content of the prepared fish sauce, thereby ensuring the fermentation effect, and also effectively improve the taste of the prepared fish sauce. Attached Figure Description

[0018] Figure 1 This is a flowchart of the method for producing fish sauce from the by-products of stinky mandarin fish according to the present invention; Figure 2 The results show the comparison of amino acid nitrogen content of fish sauce obtained in Example 1, Comparative Example 1, and Comparative Example 2; Figure 3 The results show the comparison of the total acid content of the fish sauces obtained in Example 1, Comparative Example 1, and Comparative Example 2. Figure 4 The results show the comparison of amino acid nitrogen content in fish sauce obtained at different fermentation temperatures. Detailed Implementation

[0019] The present invention will be further illustrated below with reference to specific embodiments, but these embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in this technical field. The essential features and significant effects of the present invention can be seen from the following embodiments. The described embodiments are some, but not all, embodiments of the present invention, and therefore do not limit the present invention in any way. Any non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are within the protection scope of the present invention.

[0020] It should also be understood that, for clarity, certain features of this disclosure may be described herein in the context of individual embodiments, but may also be provided in combination with each other in individual embodiments. That is, unless obviously incompatible or specifically excluded, each individual embodiment is considered to be combinable with any other embodiment, and such combination is considered to represent another different embodiment. Conversely, for brevity, various features of this disclosure described in the context of individual embodiments may also be provided individually or in any sub-combination. Finally, while a particular embodiment may be described as part of a series of steps or part of a more general structure, each step or substructure may also be considered an independent embodiment in itself.

[0021] Example 1 Combination Figure 1 As shown in this embodiment, a method for producing fish sauce from mandarin fish by-products includes the following steps: Step 1: Obtain hydrolyzed peptides from the enzymatic hydrolysis of stinky mandarin fish by-products as the main raw material; The hydrolyzed peptides obtained from the enzymatic hydrolysis of the stinky mandarin fish by-products are obtained by sorting the viscera, gills, and scales of the stinky mandarin fish by-products and then using enzymatic hydrolysis technology. Specifically, neutral protease, alkaline protease, or acidic protease can be used for enzymatic hydrolysis. In this embodiment, trypsin and flavor protease are preferably used sequentially for 80 min and 160 min, respectively. After enzymatic hydrolysis, the degree of hydrolysis of the stinky mandarin fish by-products is 20%.

[0022] Step Two: Composition A compound Aspergillus protease was prepared using a koji-making process. The compound Aspergillus protease included Aspergillus oryzae, Aspergillus niger and Aspergillus rubrum, with a mass ratio of 3:2:1 for the three enzymes. Specifically, in this embodiment, the koji-making process is as follows: Soybean meal: wheat bran: water are mixed in a mass ratio of 55:45:60, then autoclaved at 0.1 MPa and 121℃ for 20 minutes, cooled to room temperature, and then inoculated with *Aspergillus oryzae*, *Aspergillus niger*, and *Aspergillus rubrum* for cultivation to obtain the respective *Aspergillus* species. The process parameters include: koji-making temperature of 28℃, koji-making time of 4 days, and inoculation amount of each *Aspergillus* species of 0.8%.

[0023] Step 3: Fermentation, Filtration, and Sterilization Using domesticated mixed Aspergillus protease as the fermentation strain, the raw materials, mainly hydrolyzed peptides from the enzymatic hydrolysis of mandarin fish by-products, are fermented and then filtered and sterilized to obtain fish sauce products.

[0024] Specifically, in this embodiment, the fermentation process is as follows: using hydrolyzed peptides obtained from the enzymatic hydrolysis of stinky mandarin fish by-products as the main raw material, the enzymes are inactivated by steaming and cooled to room temperature, then 10% salt by mass of the homogenate is added, and 0.6% mixed Aspergillus protease by mass of domesticated homogenate is inoculated. The fish sauce is then prepared by fermentation at a temperature of 32°C.

[0025] Comparative Example 1 This comparative example describes a method for producing fish sauce from stinky mandarin fish by-products. The process is basically the same as in Example 1. The main difference is that in this comparative example, when enzymatically hydrolyzing the stinky mandarin fish by-products to obtain hydrolyzed peptides, trypsin and flavor protease are used sequentially for 160 min and 80 min respectively (hydrolysis time 2:1). After enzymatic hydrolysis, the degree of hydrolysis of the stinky mandarin fish by-products is 28%.

[0026] Comparative Example 2 This comparative example describes a method for producing fish sauce from stinky mandarin fish by-products. The process is basically the same as in Example 1. The main difference is that in this comparative example, when enzymatically hydrolyzing the stinky mandarin fish by-products to obtain hydrolyzed peptides, trypsin and flavor protease are used sequentially for 120 min and 120 min respectively (hydrolysis time 1:1). After enzymatic hydrolysis, the degree of hydrolysis of the stinky mandarin fish by-products is 28%.

[0027] Enzymatic hydrolysis before fermentation can accelerate the fermentation process, but while shortening the fermentation cycle, attention should also be paid to the fermented flavor. The greater the degree of enzymatic hydrolysis, the stronger the bitterness, thus affecting the flavor of the fermented product. According to... Figure 2 It can be seen that the amino acid nitrogen content of the fish sauce obtained after fermentation in Example 1 (i.e., the line corresponding to degree of hydrolysis 3) is higher than that in Comparative Example 1 (the line corresponding to degree of hydrolysis 1) and Comparative Example 2 (the line corresponding to degree of hydrolysis 2). This may be because a low degree of hydrolysis produces a large number of small peptides during the hydrolysis process, which is more conducive to fermentation.

[0028] Total acid is the organic acid produced during the fermentation of sugar sources by various enzymes secreted by Aspergillus. In this study, the total acid content decreased as fermentation progressed. This is because the transamination and deamination processes of Aspergillus during fermentation produce alkaline ammonia and amines, which gradually decrease the total acid content in the fermentation broth until it stabilizes after reaching a certain value. Figure 3 It can be seen that the total acid content in Comparative Example 1 shows a trend of first decreasing, then increasing, and then decreasing again, which is speculated to be due to contamination by miscellaneous bacteria during fermentation. The total acid content changes in Example 1 and Comparative Example 2 show similar trends, indicating that the fermentation process is normal. However, considering both the amino acid nitrogen content and the total acid content, a lower degree of hydrolysis is more beneficial to the expected fermentation results and is suitable as a reference value for optimizing the degree of hydrolysis. Therefore, this application preferably controls the degree of hydrolysis of the enzymatic hydrolysis of the stinky mandarin fish by-product to be 18%~22%, and more preferably 20%.

[0029] Example 2 This embodiment describes a method for producing fish sauce from stinky mandarin fish by-products. The process is basically the same as in Embodiment 1, except that salt accounting for 8% of the homogenate mass is added during the fermentation process in this embodiment.

[0030] Example 3 This embodiment describes a method for producing fish sauce from stinky mandarin fish by-products. The process is basically the same as in Embodiment 1, except that salt accounting for 18% of the homogenate mass is added during the fermentation process in this embodiment.

[0031] Comparative Example 3 This comparative example describes a method for producing fish sauce from the by-products of fermented mandarin fish. The process is basically the same as in Example 1, except that salt, accounting for 22% of the homogenate mass, is added during the fermentation process in this comparative example.

[0032] The comparative results of Examples 1-3 and Comparative Example 3 show that the overall effect of salt addition on amino nitrogen is not significantly different. Total acid value represents the combined effect of sugar and nitrogen metabolism during fermentation; an increase in total acid value indicates vigorous sugar metabolism, while a decrease indicates vigorous nitrogen metabolism. As fermentation progresses, the total acid value generally decreases, indicating vigorous nitrogen metabolism during fermentation. However, traditional fish sauce involves adding a large amount of salt (20%–30%) during processing for fermentation (antibacterial effect). High salt content is not only unpalatable to consumers but also does not meet their health requirements. Therefore, this application preferably adds 8%–18% salt, and more preferably 10% salt, to better suit consumer taste, and its amino nitrogen content is not significantly different from existing technologies.

[0033] Example 4 This embodiment describes a method for producing fish sauce from mandarin fish by-products. The process is basically the same as in Embodiment 1, except that the fermentation temperature in this embodiment is 36°C.

[0034] Comparative Example 4 This comparative example describes a method for producing fish sauce from fermented mandarin fish by-products. The process is basically the same as in Example 1, except that the fermentation temperature in this comparative example is 28°C.

[0035] Comparative Example 5 This comparative example describes a method for producing fish sauce from the by-products of fermented mandarin fish. The process is basically the same as in Example 1, except that the fermentation temperature in this comparative example is 40°C.

[0036] Since low-salt conditions are unfavorable for inhibiting bacteria, appropriately raising the temperature can, to some extent, suppress contamination by other microorganisms while also promoting rapid fermentation. However, excessively high temperatures can also affect enzyme activity and the growth and reproduction of the starter culture itself; therefore, selecting a suitable fermentation temperature is crucial. Figure 4 It can be seen that the growth trend of amino nitrogen content is basically the same at different temperatures: rapid growth in the early stage of fermentation, followed by a sharp decline after reaching a certain peak. This may be due to the low utilization rate of solid-state fermentation materials, leading to microbial decomposition metabolism exceeding anabolism in the later stage of fermentation, resulting in a rapid decrease in amino nitrogen content. In summary, a fermentation temperature of 30-34℃ yields better results, with 32℃ being a further preferred temperature, where the amino nitrogen content is slightly higher than in the other groups. Comparative Example 6 This comparative example describes a method for producing fish sauce from stinky mandarin fish by-products. The process is basically the same as in Example 1, except that the amount of domesticated mixed Aspergillus protease added in this comparative example is 0.2% of the homogenate mass.

[0037] Comparative Example 7 This comparative example describes a method for producing fish sauce from stinky mandarin fish by-products. The process is basically the same as in Example 1, except that the amount of domesticated mixed Aspergillus protease added in this comparative example is 0.8% of the homogenate mass.

[0038] Comparing Example 1 with Comparative Examples 6 and 7, the results show that the amount of starter culture added directly affects fermentation. If the amount of starter culture added is too small, the microbial reproduction is slow, leading to a prolonged total fermentation cycle; if the amount of starter culture added is too large, it results in energy waste and increased production costs. Specifically, the growth trend of amino nitrogen content was basically consistent across different amounts of starter culture added. Relatively speaking, the amino nitrogen content was higher in Example 1, and the total acid gradually decreased as fermentation progressed, eventually reaching a uniform level in the later stages of fermentation. Therefore, it can be inferred that the amount of starter culture added has a relatively small impact on total acid.

[0039] Comparative Example 8 This comparative example describes a method for producing fish sauce from the by-products of fermented mandarin fish. The process is basically the same as in Example 1, except that the koji-making temperature in this comparative example is 22°C.

[0040] Comparative Example 9 This comparative example describes a method for producing fish sauce from the by-products of fermented mandarin fish. The process is basically the same as in Example 1, except that the koji-making temperature in this comparative example is 35°C.

[0041] Comparing Example 1 with Comparative Examples 8 and 9, the results showed that temperature had a significant impact on the growth of Aspergillus. Too low a temperature resulted in inefficient growth and metabolism, low enzyme activity, and a small number of spores; too high a temperature caused enzyme inactivation, inhibiting Aspergillus growth and metabolism, and also reducing the number of spores. Therefore, it is preferable to control the koji-making temperature at 25℃~30℃, and more preferably 28℃, to ensure high enzyme activity and a large number of spores in the culture medium.

[0042] Example 5 This embodiment of a method for producing fish sauce from mandarin fish by-products includes the following steps: Step 1: Obtain hydrolyzed peptides from the enzymatic hydrolysis of stinky mandarin fish by-products as the main raw material; In this embodiment, trypsin and flavor protease were used for enzymatic hydrolysis in sequence. After enzymatic hydrolysis, the degree of hydrolysis of the stinky mandarin fish by-product was 18%.

[0043] Step Two: Composition A compound Aspergillus protease was prepared using a koji-making process. The compound Aspergillus protease included Aspergillus oryzae, Aspergillus niger and Aspergillus rubrum, with a mass ratio of 3:2:1 for the three enzymes. Specifically, in this embodiment, the koji-making process is as follows: Soybean meal: wheat bran: water are mixed in a mass ratio of 50:50:60, then autoclaved at 0.3 MPa and 125℃ for 30 minutes, cooled to room temperature, and then inoculated with *Aspergillus oryzae*, *Aspergillus niger*, and *Aspergillus rubrum* for cultivation to obtain the respective *Aspergillus* species. The process parameters include: koji-making temperature of 25℃, koji-making time of 3 days, and inoculation amount of each *Aspergillus* species of 0.4%.

[0044] Step 3: Fermentation, Filtration, and Sterilization In this embodiment, the fermentation process is as follows: using hydrolyzed peptides obtained from the enzymatic hydrolysis of stinky mandarin fish by-products as the main raw material, the enzymes are inactivated by steaming and cooled to room temperature, and then 8% salt by mass of the homogenate is added. Then, 0.4% mixed Aspergillus protease by mass of domesticated homogenate is inoculated. The fish sauce is prepared by fermentation at a temperature of 30°C.

[0045] Example 6 This embodiment of a method for producing fish sauce from mandarin fish by-products includes the following steps: Step 1: Obtain hydrolyzed peptides from the enzymatic hydrolysis of stinky mandarin fish by-products as the main raw material; In this embodiment, trypsin and flavor protease were used for enzymatic hydrolysis in sequence. After enzymatic hydrolysis, the degree of hydrolysis of the stinky mandarin fish by-product was 22%.

[0046] Step Two: Composition A compound Aspergillus protease was prepared using a koji-making process. The compound Aspergillus protease included Aspergillus oryzae, Aspergillus niger and Aspergillus rubrum, with a mass ratio of 3:2:1 for the three enzymes. Specifically, in this embodiment, the koji-making process is as follows: Soybean meal: wheat bran: water are mixed in a mass ratio of 60:40:50, then autoclaved at 0.2 MPa and 123°C for 24 minutes, cooled to room temperature, and then inoculated with *Aspergillus oryzae*, *Aspergillus niger*, and *Aspergillus rubrum* for cultivation to obtain the respective *Aspergillus* species. The process parameters include: koji-making temperature of 30°C, koji-making time of 3.5 days, and inoculation amount of each *Aspergillus* species of 1.2%.

[0047] Step 3: Fermentation, Filtration, and Sterilization In this embodiment, the fermentation process is as follows: using hydrolyzed peptides obtained from the enzymatic hydrolysis of stinky mandarin fish by-products as the main raw material, the enzymes are inactivated by steaming and cooled to room temperature, and then 15% of salt by mass of homogenate is added. Then, 0.8% of domesticated mixed Aspergillus protease by mass of homogenate is inoculated. The fish sauce is prepared by fermentation at a temperature of 36°C.

Claims

1. A method for producing fish sauce from mandarin fish by-products, characterized in that, include: Hydrolyzed peptides obtained from the enzymatic hydrolysis of stinky mandarin fish by-products are used as the main raw materials, wherein the degree of hydrolysis of the stinky mandarin fish by-products is 18%~22%; A compound Aspergillus protease was prepared using a koji-making process. The compound Aspergillus protease included Aspergillus oryzae, Aspergillus niger and Aspergillus rubrum, with a mass ratio of 3:2:1 for the three enzymes. A well-domesticated mixed Aspergillus protease was used as the fermentation strain to ferment raw materials mainly composed of hydrolyzed peptides from the enzymatic hydrolysis of mandarin fish by-products. Salt accounting for 8% to 18% of the homogenate mass was added during the fermentation process, and the fermentation temperature was 30 to 34℃.

2. The method for producing fish sauce from mandarin fish by-products according to claim 1, characterized in that, During fermentation, 10% salt by mass of the homogenate is added to the fermentation raw material, and the fermentation temperature is 32℃.

3. The method for producing fish sauce from mandarin fish by-products according to claim 1, characterized in that, The degree of hydrolysis of the enzymatic hydrolysis of the stinky mandarin fish by-products is 20%.

4. The method for producing fish sauce from the by-products of stinky mandarin fish according to any one of claims 1-3, characterized in that, The amount of the domesticated mixed Aspergillus protease added is 0.4% to 0.8% of the homogenate mass.

5. The method for producing fish sauce from the by-products of stinky mandarin fish according to any one of claims 1-3, characterized in that, The process involves using a domesticated compound Aspergillus protease as the fermentation strain to ferment raw materials, primarily hydrolyzed peptides derived from the enzymatic hydrolysis of stinky mandarin fish byproducts. Specifically, the process includes: using hydrolyzed peptides derived from the enzymatic hydrolysis of stinky mandarin fish byproducts as the main raw material, cooking to inactivate the enzyme, cooling to room temperature, adding salt, and inoculating with a domesticated mixed Aspergillus protease. Fermentation then yields fish sauce.

6. The method for producing fish sauce from the by-products of stinky mandarin fish according to any one of claims 1-3, characterized in that, The specific process for making koji is as follows: after mixing soybean meal, wheat bran and water in a mass ratio of (50~60): (40~50): (50~70), the mixture is subjected to high-pressure sterilization and then cooled to room temperature. Then, Aspergillus oryzae, Aspergillus niger and Aspergillus rubrum are inoculated and cultured to prepare each Aspergillus species.

7. The method for producing fish sauce from mandarin fish by-products according to claim 6, characterized in that, The process parameters for the koji-making process include: koji-making temperature of 25℃~30℃, koji-making time of 3~4 days, and inoculation amount of each Aspergillus species of 0.4%~1.2%.

8. The method for producing fish sauce from mandarin fish by-products according to claim 6, characterized in that, The high-pressure sterilization process is performed under high pressure at 0.1~0.3 MPa and 120~125℃ for 20~30 min.

9. The method for producing fish sauce from mandarin fish by-products according to claims 1-3, characterized in that, The hydrolyzed peptides obtained from the enzymatic hydrolysis of the stinky mandarin fish by-products were obtained by sequentially enzymatically hydrolyzing the stinky mandarin fish by-products with trypsin and flavor protease.

10. The method for producing fish sauce from mandarin fish by-products according to claim 9, characterized in that, The enzymatic hydrolysis times for trypsin and flavor protease on the by-products of stinky mandarin fish were 70-90 min and 150-160 min, respectively.

Images