Composite probiotic fermented fish sauce and preparation method thereof

Abstract

The invention discloses a compound probiotic fermented fish sauce and a preparation method thereof. The method comprises the following steps: cleaning fish and leftovers, adding distilled water, pulping to obtain fish cream, adding beta-D-glucose, glucose oxidase and catalase into the fish cream, and carrying out primary enzymolysis under stirring; adjusting the pH value of the primary enzymatic hydrolysate to be neutral, adding a compound enzyme to carry out secondary enzymatic hydrolysis, and carrying out enzyme deactivation to obtain a secondary enzymatic hydrolysate; adding table salt to obtain enzymatic hydrolysate; soybean meal, green beans, bran and water are mixed to obtain a koji material, the koji material is cooled to the room temperature after high-pressure sterilization, compound probiotics are inoculated for koji making, mold koji is added into the enzymatic hydrolysate for fermentation, electrodialysis desalination is conducted on fermentation liquor, then high-pressure sterilization is conducted, and the fish sauce is obtained. The fishy smell in the leftovers is removed by adding beta-D-glucose, glucose oxidase and catalase, and then the fishy smell is further degraded through fermentation; the green beans are added into the koji to prepare the koji, so that the fish sauce obtained by fermentation can keep specific fragrance, and the fish sauce product with good flavor and low fishy smell is obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of aquatic product processing, and particularly relates to a compound probiotic fermented fish sauce and a preparation method thereof. Background Art

[0002] The traditional production process of fish sauce fermentation uses low-value anchovies as raw materials. After fully mixing salt and fish in a certain ratio, the above mixture is reserved for fermentation. Without adding any external enzymes, various enzymes contained in the fish itself, including cathepsin and other enzymes, and natural microorganisms jointly carry out the degradation effect. Through the action of various enzymes existing in the fermentation system itself, the proteins, fats, and polysaccharide substances in the fish body are degraded into small molecules that are easily absorbed, such as amino acids, fatty acids, and monosaccharides. Although this process does not require the addition of any external substances to save costs, in terms of comprehensive benefits, the economic benefits are very low. There are three reasons. First, the natural fermentation process requires a long cycle, generally up to two to three years, and the required time cost is high. Second, the natural fermentation yield is low, and the production capacity is in short supply. Third, the nutrition is not comprehensive enough. Since no enzymes are added during the whole fermentation process, the fermentation process is not directional, which leads to the lack of comprehensiveness in the nutrition of the final product.

[0003] Fermenting fish sauce with probiotics can greatly shorten the fermentation cycle. However, the fermentation raw materials of fish sauce are generally low-value anchovies or other fish and their by-products. It generally takes a certain amount of time to transport these by-products to the fish sauce production site. Even if they are stored frozen, they will still be oxidized during this process, producing more fishy and smelly odors. Therefore, how to remove fishy odors has always been a key problem to be solved in the production of fish sauce. At present, the main deodorization methods include adding substances such as activated carbon for deodorization or passing through a nanofiltration membrane for deodorization. The deodorization effect of activated carbon and the like is not good, and the nanofiltration membrane deodorization not only has a high cost but also a very low efficiency. In addition, due to the short fermentation time of probiotic fermented fish sauce, the unique aroma of fish sauce is relatively weak. Therefore, a method for compound probiotic fermentation of fish sauce is needed, which can not only shorten the fish sauce fermentation time but also maintain the unique aroma of fish sauce, and can effectively remove fishy odors to obtain a fish sauce product with a better taste. Summary of the Invention

[0004] In view of the above-mentioned prior art, the object of the present invention is to provide a compound probiotic fermented fish sauce and a preparation method thereof. The present invention removes the fishy odor substances in fish and by-products by adding β-D-glucose, glucose oxidase, and catalase, and further degrades the fishy odor substances through fermentation; by adding green beans to the koji material to make koji, the fermented fish sauce can maintain its unique aroma, and a fish sauce product with good flavor and low fishy odor is obtained.

[0005] To achieve the above object, the present invention adopts the following technical solutions: In the first aspect of the present invention, a method for preparing a compound probiotic fermented fish sauce is provided, comprising the following steps: (1) Wash the fish and fish by-products, add distilled water to make a fish paste, add β-D-glucose, glucose oxidase and catalase to the fish paste, and perform primary enzymatic hydrolysis under stirring. After inactivating the enzyme, obtain the primary enzymatic hydrolysate; adjust the pH of the primary enzymatic hydrolysate to neutral, add a compound enzyme for secondary enzymatic hydrolysis, and obtain the secondary enzymatic hydrolysate after inactivating the enzyme; add salt to the secondary enzymatic hydrolysate to obtain the enzymatic hydrolysate; (2) Mix soybean meal, green beans, wheat bran and water to obtain koji material. After autoclaving the koji material and cooling it to room temperature, inoculate with a compound probiotic to make koji to obtain seed koji. Add the seed koji to the enzymatic hydrolysate for fermentation, desalt the fermentation broth by electrodialysis, and then perform autoclaving to obtain fish sauce.

[0006] Preferably, in step (1), the addition amount of β-D-glucose is 1% of the mass of the fish and fish by-products; the addition amount of glucose oxidase accounts for 0.1-0.5% of the mass of the fish and fish by-products; the addition amount of catalase is 1-3% of the mass of the fish and fish by-products.

[0007] Preferably, in step (1), the temperature of the primary enzymatic hydrolysis is 25-30 °C, and the time is 4-8 h; the rotation speed of the stirring is ≥200 rmp.

[0008] Preferably, in step (1), the compound enzyme is selected from at least one of neutral protease, flavor protease, pepsin, bromelain, and papain; the addition amount of the compound enzyme accounts for 0.1-1% of the mass of the primary enzymatic hydrolysate; the temperature of the secondary enzymatic hydrolysis is 50 °C, and the enzymatic hydrolysis time is 4-8 h.

[0009] Preferably, in step (1), the addition amount of salt accounts for 9% of the mass of the secondary enzymatic hydrolysate.

[0010] Preferably, in step (2), the green beans are the beans obtained 12-16 days after the soybean blossoms; the mass ratio of the soybean meal, green beans, wheat bran and water is 25:5:20:50; the compound probiotic is a mixture of Zygosaccharomyces rouxii, Saccharomyces cerevisiae and Bacillus subtilis in a mass ratio of 1:1:1; the inoculation amount of the compound probiotic accounts for 1-5% of the mass of the koji material; the temperature of making koji is 37 °C and the time is 3-7 d.

[0011] The strain preservation number of Zygosaccharomyces rouxii is CICC 33378, purchased from the China Center for Industrial Culture Collection; The strain preservation number of Saccharomyces cerevisiae is CICC 1017, purchased from the China Center for Industrial Culture Collection; The preservation number of the Bacillus subtilis strain is CGMCC 1.14985, which is purchased from the China General Microbiological Culture Collection Center.

[0012] Preferably, in step (2), the addition amount of the koji is 20% of the mass of the enzymatic hydrolysate; the fermentation temperature is 40 °C, and the fermentation time is 30 d.

[0013] Preferably, in step (2), the voltage for electrodialysis desalination is 30 V, and the sample loading flow rate is 50 L / hour.

[0014] In the second aspect of the present invention, there is provided the use of the above preparation method in improving the flavor of fish sauce and reducing the fishy smell of fish sauce.

[0015] In the third aspect of the present invention, there is provided a composite probiotic fermented fish sauce obtained by the above preparation method.

[0016] Advantages of the present invention: (1) The present invention adopts the traditional method of fermenting fish sauce with probiotics. First, fish and their by-products are enzymatically hydrolyzed, then koji is prepared and fermented with composite probiotics, which shortens the fermentation time of fish sauce. The process flow is simple and suitable for large-scale production.

[0017] (2) The present invention removes fishy substances in fish and their by-products by adding β-D-glucose, glucose oxidase and catalase, and further degrades fishy substances through fermentation; by adding green beans to the koji material to make koji, the fermented fish sauce can maintain its unique aroma, and a fish sauce product with good flavor and low fishy smell is obtained. Specific embodiments

[0018] It should be noted that the following detailed description is illustrative and is intended to provide further description of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0019] As introduced in the background art section, the current main deodorization methods include adding substances such as activated carbon to remove fishy smell or passing through a nanofiltration membrane to remove fishy smell. The deodorization effect of activated carbon and the like is not good, and the nanofiltration membrane deodorization not only has a high cost but also a very low efficiency. In addition, due to the short fermentation time of probiotic fermented fish sauce, the unique aroma of fish sauce is relatively weak.

[0020] Based on this, the purpose of the present invention is to provide a composite probiotic fermented fish sauce and its preparation method. Since the raw materials for making fish sauce, fish and their by-products, in addition to the fishy smell they contain, produce fishy substances such as aldehydes, ketones, and trimethylamine due to oxidation during transportation. In particular, anchovies, which are low-value fish, are mainly used to prepare feed. This is because anchovies are very easy to spoil after landing and need to be frozen immediately after landing. Even so, the fishy smell of anchovies is stronger than that of other fish.

[0021] In the present invention, β-D-glucose and catalase are first added to fish and fish by-products. β-D-glucose can react with oxygen under the catalysis of glucose oxidase to generate hydrogen peroxide and gluconic acid. Gluconic acid can react with the amine substances produced by fish and fish by-products, thereby removing fishy smell. Hydrogen peroxide can not only sterilize and remove the bacteria in fish and fish by-products to prevent further spoilage, but also catalyze catalase to decompose the peroxides generated by the oxidation of fish and fish by-products, further removing fishy smell. However, if hydrogen peroxide is not removed, it will not only oxidize fish meat, but also inhibit the growth of strains in subsequent fermentation. Therefore, catalase consumes hydrogen peroxide to produce oxygen, which can provide oxygen for the reaction of β-D-glucose, forming a positive cycle. An excessive amount of catalase needs to be added to ensure that all hydrogen peroxide is consumed, and stirring is beneficial to accelerating the consumption of hydrogen peroxide by catalase. The fermentation of compound probiotics will further degrade the residual fishy substances. Although the fermentation of compound probiotics can greatly shorten the production time of fish sauce, the aroma of fish sauce is relatively weak. By adding green soybeans obtained 12 to 16 days after the soybeans bloom during the koji-making process, it helps to improve the aroma of fish sauce. Compared with soybeans, the content of hexadecenoic acid (C16:1) in green soybeans obtained 12 to 16 days after the soybeans bloom is very high. Although hexadecenoic acid is a monounsaturated fatty acid, it is a ω-7 fatty acid. Adding green soybeans to the koji material for koji-making and being utilized by probiotics during the fermentation process makes the produced fish sauce have a stronger aroma, overcomes the problem of the weak aroma of fish sauce with short-term fermentation, and improves the quality of fish sauce.

[0022] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below with specific embodiments.

[0023] The test materials used in the embodiments of the present invention are all conventional test materials in the art and can be obtained through commercial channels.

[0024] Embodiment (1) Wash the anchovies (including internal organs) and mix them with distilled water in a ratio of 1:1 to make fish paste. Take 1 kg of fish paste, add 5 g of β-D-glucose (Hubei Biaoyue Biotechnology Development Co., Ltd., CAS 492-61-5), 1.5 g of glucose oxidase (10,000 U / g, Leshengyuan Biotechnology (Nanjing) Co., Ltd.), and 10 g of catalase (100,000 U / g, Shaanxi Chenming Biotechnology Co., Ltd.), stir at a speed of 300 rmp, and control the enzymatic hydrolysis temperature at 28 °C for 6 h. After enzymatic hydrolysis, obtain the primary enzymatic hydrolysate and inactivate the enzymes at 121 °C for 20 min. Add 0.3 mol / L NaOH solution to the primary enzymatic hydrolysate to adjust the pH to neutral. Add 0.3% flavor protease (100,000 U / g, Hebei Zhongzhisheng Biotechnology Co., Ltd.) and 0.3% neutral protease (50,000 U / g, Sichuan Huanxu Biotechnology Co., Ltd.) to the primary enzymatic hydrolysate, carry out enzymatic hydrolysis at 50 °C for 6 h, and inactivate the enzymes at 121 °C for 20 min to obtain the secondary enzymatic hydrolysate. Add 9 wt% salt (sodium chloride) to the secondary enzymatic hydrolysate and mix evenly to obtain the enzymatic hydrolysate.

[0025] (2) Mix 250 g of soybean meal, 50 g of green beans, 200 g of wheat bran, and 500 g of distilled water, sterilize with high-pressure steam at 98 °C and then cool to room temperature. Add 10 g of Zygosaccharomyces rouxii (CICC 33378), 10 g of Saccharomyces cerevisiae (CICC 1017), and 10 g of Bacillus subtilis (CGMCC 1.14985), and culture at 37 °C for 5 d, turning the koji once a day to obtain the koji seed.

[0026] (3) Take 500 g of the enzymatic hydrolysate prepared in step (1), add 100 g of the koji seed prepared in step (2), and ferment at 40 °C for 30 days. After fermentation, perform electrodialysis desalination on the fermentation broth, with an operating voltage of 30 V and a sample loading flow rate of 50 L / h. After desalination, use a plate and frame filter press with a 100-mesh filter cloth to perform pressure filtration to remove impurities at 0.4 MPa, and then perform high-pressure steam sterilization at 98 °C to obtain fish sauce.

[0027] Comparative Example 1 (1) Wash the anchovies (including internal organs) and mix them with distilled water in a ratio of 1:1 to make fish paste. Take 1 kg of fish paste, add 0.3% flavor protease (100,000 U / g, Hebei Zhongzhisheng Biotechnology Co., Ltd.) and 0.3% neutral protease (50,000 U / g, Sichuan Huanxu Biotechnology Co., Ltd.), carry out enzymatic hydrolysis at 50 °C for 6 h, and inactivate the enzymes at 121 °C for 20 min to obtain the enzymatic hydrolysate. Add 9 wt% salt (sodium chloride) to the enzymatic hydrolysate and mix evenly.

[0028] (2) Mix 250 g of soybean meal, 50 g of soybeans, 200 g of wheat bran and 500 g of distilled water, sterilize at high pressure steam at 98 °C and then cool to room temperature. Add 10 g of Zygosaccharomyces rouxii (CICC 33378), 10 g of Saccharomyces cerevisiae (CICC 1017), and 10 g of Bacillus subtilis (CGMCC No. 23784), and culture at 37 °C for 5 days, turning the koji once a day to obtain the starter koji.

[0029] (3) Take 500 g of the enzymolysis solution prepared in step (1), add 100 g of the starter koji prepared in step (2), and ferment at 40 °C for 30 days. After fermentation, perform electrodialysis desalination on the fermentation broth, with an operating voltage of 30 V and a sample loading flow rate of 50 L / hour. After desalination, use a plate and frame filter press with a 100-mesh filter cloth to perform pressure filtration to remove impurities at 0.4 MPa, and then perform high-pressure steam sterilization at 98 °C to obtain fish sauce.

[0030] Comparative Example 2 (1) Wash the anchovies (including internal organs) and mix them with distilled water in a ratio of 1:1 to make a fish paste. Take 1 kg of the fish paste, add 5 g of β-D-glucose (Hubei Biaoyue Biotechnology Development Co., Ltd. CAS 492-61-5), 1.5 g of glucose oxidase (10,000 U / g, Leshengyuan Biotechnology (Nanjing) Co., Ltd.), and 10 g of catalase (100,000 U / g, Shaanxi Chenming Biotechnology Co., Ltd.), stir at a speed of 300 rmp, and control the enzymolysis temperature at 28 °C for 6 hours. After enzymolysis, obtain the primary enzymolysis solution and inactivate the enzyme at a high temperature of 121 °C for 20 minutes. Add 0.3 mol / L of NaOH solution to the primary enzymolysis solution to adjust the pH to neutral. Add 0.3% of flavor protease (100,000 U / g, Hebei Zhongzhi Sheng Biotechnology Co., Ltd.) and 0.3% of neutral protease (50,000 U / g, Sichuan Huanxu Biotechnology Co., Ltd.) to the primary enzymolysis solution, enzymolyze at 50 °C for 6 hours, and inactivate the enzyme at a high temperature of 121 °C for 20 minutes to obtain the secondary enzymolysis solution. Add 9 wt% of salt (sodium chloride) to the secondary enzymolysis solution and mix evenly to obtain the enzymolysis solution.

[0031] (2) Mix 250 g of soybean meal, 50 g of soybeans, 200 g of wheat bran and 500 g of distilled water, sterilize at high pressure steam at 98 °C and then cool to room temperature. Add 10 g of Zygosaccharomyces rouxii (CICC 33378), 10 g of Saccharomyces cerevisiae (CICC 1017), and 10 g of Bacillus subtilis (CGMCC No. 23784), and culture at 37 °C for 5 days, turning the koji once a day to obtain the starter koji.

[0032] (3) Take 500 g of the enzymolysis solution prepared in step (1), add 100 g of the koji prepared in step (2), and ferment at 40 °C for 30 days. After fermentation, perform electrodialysis desalination on the fermentation broth with an operating voltage of 30 V and a sample loading flow rate of 50 L / h. After desalination, use a plate and frame filter press with a 100-mesh filter cloth to filter out impurities at 0.4 MPa, and then perform high-pressure steam sterilization at 98 °C to obtain fish sauce.

[0033] Comparative Example 3 (1) Wash the anchovies (including internal organs) and mix them with distilled water at a ratio of 1:1 to make a fish paste. Take 1 kg of the fish paste, add 0.3% flavor protease (100,000 U / g, Hebei Zhongzhi Sheng Biotechnology Co., Ltd.) and 0.3% neutral protease (50,000 U / g, Sichuan Huanxu Biotechnology Co., Ltd.), enzymolyze at 50 °C for 6 h, and inactivate the enzyme at 121 °C for 20 min to obtain an enzymolysis solution. Add 9 wt% salt (sodium chloride) to the enzymolysis solution and mix evenly.

[0034] (2) Mix 250 g of soybean meal, 50 g of green soybeans (16 days after soybean flowering), 200 g of wheat bran and 500 g of distilled water, sterilize at 98 °C with high-pressure steam and cool to room temperature, add 10 g of Zygosaccharomyces rouxii (CICC 33378), 10 g of Saccharomyces cerevisiae (CICC 1017), 10 g of Bacillus subtilis (CGMCC No. 23784), and culture at 37 °C for 5 d, turning the koji once a day to obtain koji.

[0035] (3) Take 500 g of the enzymolysis solution prepared in step (1), add 100 g of the koji prepared in step (2), and ferment at 40 °C for 30 days. After fermentation, perform electrodialysis desalination on the fermentation broth with an operating voltage of 30 V and a sample loading flow rate of 50 L / h. After desalination, use a plate and frame filter press with a 100-mesh filter cloth to filter out impurities at 0.4 MPa, and then perform high-pressure steam sterilization at 98 °C to obtain fish sauce.

[0036] Test Example 1: Detection of Physicochemical Indexes of Fish Sauce Detect the total nitrogen, amino acid nitrogen, trimethylamine content, amino acid content, volatile ester content, and volatile acid content of the fish sauce products prepared in the examples and Comparative Examples 1-3; the obtained results are shown in Table 1.

[0037] The total nitrogen content was determined by the Kjeldahl method (GB 5009.5-2010); The trimethylamine content was determined by headspace gas chromatography-mass spectrometry of GB5009.179-2016; The amino acid nitrogen content was determined by the formaldehyde titration method (GB / T 5009.39-2003); The amino acid content was determined by an automatic amino acid analyzer; The contents of volatile esters and volatile acids were detected by solid-phase microextraction gas chromatography-mass spectrometry (HPMS-HS-GC-MS). Table 1 Physical and chemical indicators Total nitrogen and amino acid nitrogen are indicators of the quality of fish sauce. Although the water content in green beans is the main component and the nitrogen content in soybeans is higher than that in green beans, fish sauce is a product of the fermentation of fish products, and the nitrogen content mainly comes from fish and by-products. The better the fermentation degree, the higher the contents of protein, amino acids, etc. in the fish sauce. Among amino acids, glutamic acid can increase the umami taste of fish sauce, glycine can increase the sweet taste, and histidine increases the bitter taste. These three representative amino acids were selected among amino acids, and the taste of fish sauce can be judged according to the contents of the three amino acids. Trimethylamine, volatile esters, and acids can show the flavor of fish sauce. The lower the content of trimethylamine, the less fishy smell the fish sauce has, and the higher the volatile esters and acids, the better the aroma of the fish sauce. It can be seen from Table 1 that the fish sauce prepared in the examples is superior to Comparative Examples 1-3 in terms of quality, taste, and aroma. By comparing Comparative Examples 1-3, it can be seen that adding β-D-glucose, glucose oxidase, and catalase can remove fishy smell and partially improve the aroma of fish sauce, while adding green beans for koji making can hardly reduce the fishy smell of fish sauce but can improve the aroma of fish sauce, indicating that adding green beans can improve the fermentation degree.

[0038] Test Example 2: Sensory test Sensory tests were used to evaluate the sensory preferences of the fish sauces prepared in the examples and Comparative Examples 1-3. An evaluation panel consisting of 10 people trained in sensory evaluation was formed, randomly numbered for evaluation, and evaluated and scored in terms of the umami taste, fishy smell, aftertaste, mellow feeling, and seafood flavor of the fish sauce, and the total score was statistically calculated. The sensory evaluation form is shown in Table 2, and the sensory evaluation results are shown in Table 3.

[0039] Table 2 Sensory evaluation form Table 3 Results of sensory tests It can be seen from Table 2 that compared with the fish sauces prepared in Comparative Examples 1-3, the sensory test evaluation of the fish sauce products prepared in the examples is higher. The score of Comparative Example 3 is lower than that of Comparative Example 2, mainly because although the fish sauce in Comparative Example 3 has an obvious aroma but also an obvious fishy smell, and the two odors conflict, giving people a bad sense, so the sensory evaluation is slightly lower than that of Comparative Example 2.

[0040] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A method for preparing a composite probiotic fermented fish sauce, characterized in that: The following steps are involved: (1) Washing fish and waste materials, adding distilled water to the fish paste, adding β-D-glucose, glucose oxidase and catalase to the fish paste, performing a primary enzymolysis under stirring, and obtaining a primary enzymolysis solution after inactivating the enzymes; adjusting the pH of the primary enzymolysis solution to neutral, adding a composite enzyme to perform a secondary enzymolysis, and obtaining a secondary enzymolysis solution after inactivating the enzymes; adding salt to the secondary enzymolysis solution to obtain an enzymolysis solution; (2) Soybean meal, green beans, bran and water are mixed to obtain koji material, which is sterilized under high pressure and then cooled to room temperature, inoculated with composite probiotics to obtain seed koji, which is added to enzymatic solution for fermentation, the fermentation solution is desalted by electrodialysis, and then sterilized under high pressure to obtain fish sauce.

2. The preparation method according to claim 1, characterized in that: In step (1), the amount of β-D-glucose added is 1% of the mass of the fish and its waste; the amount of glucose oxidase added is 0.1-0.5% of the mass of the fish and its waste; and the amount of catalase added is 1-3% of the mass of the fish and its waste.

3. The preparation method according to claim 1, characterized in that: In step (1), the temperature of the primary enzymatic hydrolysis is 25-30°C, and the time is 4-8 hours; the stirring speed is ≥200 rpm.

4. The preparation method according to claim 1, characterized in that: In step (1), the compound enzyme is selected from at least one of neutral protease, flavor protease, pepsin, bromelain and papain; the amount of the compound enzyme added accounts for 0.1-1% of the mass of the primary enzymatic hydrolysis solution; the temperature of the secondary enzymatic hydrolysis is 50° C., and the enzymatic hydrolysis time is 4-8 hours.

5. The preparation method according to claim 1, characterized in that: In step (1), the amount of salt added accounts for 9% of the mass of the secondary enzymatic hydrolysate.

6. The preparation method according to claim 1, characterized in that: In step (2), the green beans are beans obtained 12 to 16 days after soybean flowering; the mass ratio of soybean meal, green beans, bran and water is 25:5:20:50; the composite probiotics are obtained by mixing Zygosaccharomyces rouxii, Saccharomyces cerevisiae and Bacillus subtilis in a mass ratio of 1:1:1; the inoculation amount of the composite probiotics accounts for 1 to 5% of the mass of the koji material; the koji making temperature is 37°C and the time is 3 to 7 days.

7. The preparation method according to claim 1, characterized in that: In step (2), the amount of the seed koji added is 20% of the mass of the enzymatic hydrolysate; the fermentation temperature is 40° C., and the fermentation time is 30 days.

8. The preparation method according to claim 1, characterized in that: In step (2), the voltage of the electrodialysis desalination is 30 V, and the sample loading flow rate is 50 L / hour.

9. Use of the preparation method according to any one of claims 1 to 8 in improving the flavor of fish sauce and reducing the fishy smell of fish sauce.

10. The composite probiotic fermented fish sauce obtained by the preparation method according to any one of claims 1 to 8.

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