A tilapia flavoring base and its preparation method

Abstract

This invention discloses a tilapia flavor base and its preparation method. The preparation method includes the following steps: pre-treating tilapia by-products to obtain enzymatically hydrolyzed material; adding a complex protease to the material for enzymatic hydrolysis, and subjecting it to a first pulsed electric field treatment during the hydrolysis process to obtain an enzymatic hydrolysate; pumping the enzymatic hydrolysate to a high-voltage pulsed electric field treatment chamber for a second treatment; and then post-treatment to obtain the tilapia flavor base. This invention utilizes a high-voltage pulsed electric field to fully decompose proteins in the raw materials, significantly increasing the yield of polypeptides with a molecular weight of 200-1000 Daltons, thereby obtaining richer short-chain proteins and amino acids, as well as other umami substances. This significantly increases the content of umami peptides in the enzymatic hydrolysate, improving the undesirable sensory properties of fish flavor bases prepared from tilapia by-products, resulting in a tilapia flavor base with prominent and full-bodied umami flavor.

Description

Technical Field

[0001] This invention belongs to the field of food additive processing, specifically, it relates to a tilapia flavoring base and its preparation method. Background Technology

[0002] Tilapia is a major freshwater fish species earning foreign exchange in my country, and its processing mainly involves frozen tilapia fillets. According to incomplete statistics, by-products account for up to 54% of the tilapia fillet processing. These by-products primarily consist of fish heads, bones, viscera, and skin. While some of these aquatic processing by-products are processed into low-value products such as fishmeal and fish solubles for aquaculture feed, the majority are discarded. This not only wastes resources but also easily pollutes the environment, and the valuable components within them are not fully developed and utilized. Therefore, effectively utilizing biological resources and developing various beneficial physiologically active natural substances can increase the utilization rate of fishery products, enhance the added value of related industries, and guide the fishery industry towards biotechnology and modernization.

[0003] Fish by-products can be processed into fish flavor enhancers through enzymatic hydrolysis and other processes. Fish heads and bones are rich in nucleotides, amino acids, and inorganic elements such as potassium, calcium, sodium, and magnesium, which contribute significantly to flavor. Properly processed fish by-products are a good choice for making seasoning broths, fish bone sauces, or seafood seasoning bases. Enzymatic hydrolysis of fish heads and bones results in even more flavor compounds and a richer fish aroma. Therefore, fish by-products, especially those hydrolyzed with proteases, are suitable for further processing into fish-flavored seasonings. Compared to fish meat, flavor enhancers produced through enzymatic hydrolysis offer advantages such as affordability, ease of storage, and longer-lasting flavor.

[0004] However, flavor enhancers made from fish by-products have disadvantages compared to flavor enhancers made from fish meat, such as a weak umami flavor, a strong fishy smell, and an unrealistic flavor, which not only affect the taste but also the acceptance by consumers. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a tilapia flavor base material with the advantages of prominent umami and realistic flavor prepared by using tilapia by-products, and the preparation method thereof.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0007] A method for preparing a tilapia flavoring base includes the following steps:

[0008] Prepare the ingredients, collecting the scraps from the slaughtered tilapia for later use;

[0009] Pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed.

[0010] Enzymatic hydrolysis: A complex protease is added to the material to be hydrolyzed for enzymatic hydrolysis, and the material in the process of enzymatic hydrolysis is placed in a high-voltage pulsed electric field treatment chamber for the first pulsed electric field treatment to obtain the hydrolysate.

[0011] The second processing involves pumping the enzymatic hydrolysate into a high-voltage pulsed electric field treatment chamber for a second pulsed electric field treatment to obtain a semi-finished product.

[0012] The semi-finished product is then subjected to filtration, purification, concentration, and drying to obtain tilapia flavor base.

[0013] Specifically, the enzymatic hydrolysis step includes the following steps:

[0014] After adjusting the temperature of the material to be enzymatically hydrolyzed to 50–60°C and the pH value to 5.5–7.5, a complex protease is added to the material. The amount of the complex protease added is 0.1–0.8% of the weight of the material to be enzymatically hydrolyzed.

[0015] In one process, the material to be hydrolyzed with the added complex protease is pumped into a high-voltage pulsed electric field treatment chamber for the first pulsed electric field treatment. Enzymatic hydrolysis is performed simultaneously during the treatment. The pulse frequency of the first pulsed electric field treatment is 50-200Hz, the electric field strength is 0.5-1.0kV / cm, the pulse width is 10-15μs, and the treatment time is 20-40min.

[0016] The material after the first treatment is left to stand at 50-60°C and then enzymatically hydrolyzed for 0.5-1 hour to obtain the enzymatic hydrolysate.

[0017] Specifically, in the secondary processing, the pulse frequency of the second pulse electric field treatment is 500-1000Hz, the electric field strength is 1.0-4.0kV / cm, the pulse width is 5-20μs, and the processing time is 10-30min.

[0018] Specifically, the complex protease is composed of flavor protease, bromelain, and papain in a weight ratio of (2-5): (1-3): (1-3).

[0019] Furthermore, the pretreatment step includes washing and crushing the waste material to obtain powder, mixing the powder with water at a weight ratio of 1:1 to 1.5, and then homogenizing it in a homogenizer at 10,000 to 15,000 rpm / min for 1 to 5 minutes to obtain the material to be enzymatically hydrolyzed.

[0020] Furthermore, the post-processing step also includes the following steps:

[0021] Filtration: The semi-finished product is filtered using a ceramic membrane to obtain a filtrate.

[0022] Purification: The filtrate was subjected to dextran gel chromatography to obtain a purified solution.

[0023] Concentration: The purified solution is concentrated under vacuum at a temperature of 65–85°C and a vacuum degree of -0.07–-0.1 MPa.

[0024] Drying: The product obtained after vacuum concentration is subjected to vacuum drying at a temperature of -50 to -80°C and a vacuum degree of 1 to 50 Pa. After vacuum drying, the tilapia flavor base is obtained.

[0025] Preferably, the waste materials include tilapia heads, bones, viscera, scales, or skin.

[0026] Another technical solution of the present invention to solve the above-mentioned technical problem is:

[0027] A tilapia flavoring base is prepared by the above-mentioned preparation method.

[0028] Specifically, the tilapia flavoring base is used to prepare food additives.

[0029] This invention offers the following advantages: By utilizing a high-voltage pulsed electric field to fully decompose proteins in the raw materials, the decomposition and utilization rates of proteins are improved, significantly increasing the yield of polypeptides with molecular weights of 200-1000 Daltons. This results in a richer supply of short-chain proteins and umami substances such as amino acids, significantly increasing the content of umami peptides in the enzymatic hydrolysis products. This improves the undesirable sensory properties of fish-flavored base materials prepared from tilapia by-products, resulting in a base material with prominent umami, full flavor, and health benefits. The tilapia-flavored base material of this application is prepared from natural ingredients, meeting the health needs of a wide range of consumers. Its aroma and taste are similar to those of fish-based base materials, making it a viable alternative at a lower cost. It can be used to season various soups and dishes. The preparation method of this invention is simple, convenient, and has broad application prospects. Implementation

[0030] The present application will now be described in further detail with reference to the embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit the invention.

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0032] It should be noted that the endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0033] Where specific techniques or conditions are not specified in the examples, they shall be performed in accordance with the techniques or conditions described in the literature in this field or in accordance with the product instructions. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0034] According to Example 1 of the present invention, a tilapia flavoring base for preparing food additives is prepared by means of the following steps:

[0035] Prepare materials by collecting the by-products after slaughtering tilapia for later use; preferably, the by-products include tilapia heads, bones, internal organs, scales or skin. In this embodiment, the weight of the by-products used is 500g. Since the raw materials are all fish by-products, the comprehensive utilization of freshwater fish by-product resources can be greatly improved and waste can be reduced.

[0036] The pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Further, the specific operation process of this step includes washing the waste material and crushing it to obtain powder, then mixing the powder with water at a weight ratio of 1:1, and then homogenizing it in a homogenizer at 10000 rpm / min for 1 min to obtain the material to be enzymatically hydrolyzed.

[0037] Enzymatic hydrolysis involves adding a complex protease to the material to be hydrolyzed, and then placing the material undergoing enzymatic hydrolysis in a high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment to obtain a hydrolysate. Specifically, this step further includes the following steps: adding the complex protease: after adjusting the temperature of the material to be hydrolyzed to 50°C and the pH value to 5.5, adding the complex protease to the material to be hydrolyzed, the amount of the complex protease added is 0.1% of the weight ratio of the material to be hydrolyzed; first treatment: the material to be hydrolyzed with the added complex protease is pumped into the high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment, during which enzymatic hydrolysis occurs simultaneously. The pulse frequency of the first pulsed electric field treatment is 50Hz, the electric field strength is 0.5kV / cm, the pulse width is 10μs, and the treatment time is 20min; settling: the material after the first treatment is further hydrolyzed at 50°C for 0.5h to obtain the hydrolysate. Specifically, the complex protease is a combination of flavor protease, bromelain, and papain in a weight ratio of 2:1:1. In this application, the flavor protease used is Flavorzyzme™, the papain used is PSM500, and the bromelain used is B4882, all of which were purchased commercially.

[0038] This step involves a first pulsed electric field treatment simultaneously with the enzymatic hydrolysis. Utilizing the electroporation effect of the high-voltage pulsed electric field, cell membranes rupture, cytoplasmic outflow occurs, tissue permeability increases, and effective components are significantly extracted, thereby increasing the yield and content of flavor peptides. It also significantly enhances the yield of umami peptides with molecular weights of 300–2000 Daltons, resulting in a richer variety of short-chain proteins and amino acids, producing a flavor base with a more prominent umami flavor. Furthermore, appropriate pulsed electric field treatment can alter the tertiary structure of enzyme molecules, increasing enzyme activity and effectively shortening the hydrolysis time, thus improving preparation efficiency. The synergistic effect of both treatments increases the content of flavor peptides in the enzymatic hydrolysis products of tilapia by-products, especially the content of umami peptides. At this point, all factors are appropriately balanced, representing the optimal conditions for enzymatic hydrolysis. The resulting hydrolysate has the best overall sensory evaluation, which is beneficial for producing a flavor base that removes fishy odors and enhances umami. If the pulse frequency and / or electric field strength and / or pulse width and / or treatment time are too short, they will not be sufficient to increase the yield of umami peptides. If the pulse frequency and / or electric field strength and / or pulse width and / or treatment time are too long, they will cause undesirable changes in the enzyme molecular structure, resulting in reduced enzyme activity and inhibiting the extraction of the target product.

[0039] Furthermore, by employing flavor proteases, bromelain, and papain, and strictly controlling their ratio, the target protein can be broken down into small-molecule flavor peptides, which is beneficial to the sensory quality of the flavor base. Specifically, flavor proteases contain both endopeptidases and exopeptidases, which can reduce the production of bitter peptides while breaking down proteins. Bromelain and papain are endopeptidases with specific cleavage sites. Combining these three enzymes improves the efficiency of enzymatic hydrolysis while inhibiting the formation of undesirable flavors.

[0040] The second processing involves pumping the enzymatic hydrolysate into a high-voltage pulsed electric field treatment chamber for a second pulsed electric field treatment to obtain a semi-finished product. Specifically, in the second processing, the pulse frequency of the second pulsed electric field treatment is 500 Hz, the electric field strength is 1.0 kV / cm, the pulse width is 5 μs, and the treatment time is 10 min.

[0041] This step mainly involves a second pulsed electric field treatment of the enzymatic hydrolysate. On the one hand, the high-voltage pulsed electric field is used to enhance the double bond groups on the molecular chains of the generated flavor peptides, thereby significantly improving the functional activity of the flavor peptides and enhancing their flavor effect. On the other hand, it can also inactivate enzymes and kill bacteria.

[0042] The post-processing involves sequentially filtering, purifying, concentrating, and drying the semi-finished product to obtain tilapia flavor base. This step further includes the following steps: filtration, where the semi-finished product is filtered using a ceramic membrane, preferably a 1μm ceramic membrane, to obtain a filtrate; purification, where the filtrate is separated by dextran gel chromatography using a Sephadex G15 column to obtain a purified solution; concentration, where the purified solution is concentrated under vacuum at 65°C and a vacuum degree of -0.07 MPa; and drying, where the product obtained after vacuum concentration is dried under vacuum at -50°C and a vacuum degree of 1 Pa, resulting in the tilapia flavor base. The final product, after filtration through a ceramic membrane, undergoes dextran gel chromatography to separate the chromatographic components with higher umami content, resulting in a flavor base with a rich umami flavor and excellent sensory properties.

[0043] Example 2 of the present invention provides a tilapia flavoring base for preparing food additives, the preparation method of which includes the following steps:

[0044] Prepare materials by collecting the scraps from slaughtered tilapia for later use; preferably, the scraps include the tilapia head, bones, internal organs, scales or skin, and in this embodiment, the scraps weigh 500g.

[0045] The pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Further, the specific operation process of this step includes washing the waste material and crushing it to obtain powder, then mixing the powder with water at a weight ratio of 1:2, and then homogenizing it in a homogenizer at 12000 rpm / min for 3 minutes to obtain the material to be enzymatically hydrolyzed.

[0046] Enzymatic hydrolysis involves adding a complex protease to the material to be hydrolyzed, and then placing the material undergoing enzymatic hydrolysis in a high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment to obtain the hydrolysate. Specifically, this step further includes the following steps: adding a complex protease: after adjusting the temperature of the material to be hydrolyzed to 55°C and the pH value to 6.5, a complex protease is added to the material to be hydrolyzed, with the amount of the complex protease added being 0.5% of the weight ratio of the material to be hydrolyzed; primary treatment: the material to be hydrolyzed with the added complex protease is pumped into the high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment, during which enzymatic hydrolysis occurs simultaneously. The pulse frequency of the first pulsed electric field treatment is 120Hz, the electric field strength is 0.8kV / cm, the pulse width is 12μs, and the treatment time is 30min; and settling: the material after the first treatment is further hydrolyzed at 55°C for 0.8h to obtain the hydrolysate. Specifically, the complex protease is composed of flavor protease, bromelain, and papain in a weight ratio of 3:2:2.

[0047] The second processing involves pumping the enzymatic hydrolysate into a high-voltage pulsed electric field treatment chamber for a second pulsed electric field treatment to obtain a semi-finished product. Specifically, in the second processing, the pulse frequency of the second pulsed electric field treatment is 700 Hz, the electric field strength is 3.0 kV / cm, the pulse width is 15 μs, and the treatment time is 20 min.

[0048] The post-processing involves sequentially filtering, purifying, concentrating, and drying the semi-finished product to obtain tilapia flavor base. This step further includes the following steps: filtration, where the semi-finished product is filtered using a ceramic membrane, preferably a 1μm ceramic membrane, to obtain a filtrate; purification, where the filtrate is separated by dextran gel chromatography using a Sephadex G15 column to obtain a purified solution; concentration, where the purified solution is concentrated under vacuum at a temperature of 75°C and a vacuum degree of -0.08 MPa; and drying, where the product obtained after vacuum concentration is dried under vacuum at a temperature of -65°C and a vacuum degree of 30 Pa, resulting in the tilapia flavor base.

[0049] Example 3 of the present invention provides a tilapia flavoring base for preparing food additives, the preparation method of which includes the following steps:

[0050] Prepare materials by collecting the scraps from slaughtered tilapia for later use; preferably, the scraps include the tilapia head, bones, internal organs, scales or skin, and in this embodiment, the scraps weigh 500g.

[0051] The pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Further, the specific operation process of this step includes washing the waste material and crushing it to obtain powder, then mixing the powder with water at a weight ratio of 1:5, and then homogenizing it in a homogenizer at 15000 rpm / min for 5 minutes to obtain the material to be enzymatically hydrolyzed.

[0052] Enzymatic hydrolysis involves adding a complex protease to the material to be hydrolyzed, and then placing the material undergoing enzymatic hydrolysis in a high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment to obtain the hydrolysate. Specifically, this step also includes the following steps: adding a complex protease: after adjusting the temperature of the material to be hydrolyzed to 60°C and the pH value to 7.5, a complex protease is added to the material to be hydrolyzed, with the amount of the complex protease added being 0.8% of the weight ratio of the material to be hydrolyzed; primary treatment: the material to be hydrolyzed with the added complex protease is pumped into the high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment, during which enzymatic hydrolysis occurs simultaneously. The pulse frequency of the first pulsed electric field treatment is 200Hz, the electric field strength is 1.0kV / cm, the pulse width is 15μs, and the treatment time is 40min; and settling: the material after the first treatment is further hydrolyzed at 50°C for 0.5h to obtain the hydrolysate. Specifically, the complex protease is composed of flavor protease, bromelain, and papain in a weight ratio of 5:3:3.

[0053] The second processing involves pumping the enzymatic hydrolysate into a high-voltage pulsed electric field treatment chamber for a second pulsed electric field treatment to obtain a semi-finished product. Specifically, in the second processing, the pulse frequency of the second pulsed electric field treatment is 1000Hz, the electric field strength is 4.0kV / cm, the pulse width is 20μs, and the treatment time is 30min.

[0054] The post-processing involves sequentially filtering, purifying, concentrating, and drying the semi-finished product to obtain tilapia flavor base. This step further includes the following steps: filtration, where the semi-finished product is filtered using a ceramic membrane, preferably a 1μm ceramic membrane, to obtain a filtrate; purification, where the filtrate is separated by dextran gel chromatography using a Sephadex G15 column to obtain a purified solution; concentration, where the purified solution is concentrated under vacuum at a temperature of 85°C and a vacuum degree of -0.1 MPa; and drying, where the product obtained after vacuum concentration is dried under vacuum at a temperature of -80°C and a vacuum degree of 50 Pa, resulting in the tilapia flavor base.

[0055] Example 4 of the present invention provides a tilapia flavoring base for preparing food additives, the preparation method of which includes the following steps:

[0056] Prepare materials by collecting the scraps from slaughtered tilapia for later use; preferably, the scraps include the tilapia head, bones, internal organs, scales or skin, and in this embodiment, the scraps weigh 500g.

[0057] The pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Further, the specific operation process of this step includes washing the waste material and crushing it to obtain powder, then mixing the powder with water at a weight ratio of 1:1, and then homogenizing it in a homogenizer at 10000 rpm / min for 1 min to obtain the material to be enzymatically hydrolyzed.

[0058] Enzymatic hydrolysis involves adding a complex protease to the material to be hydrolyzed, and then placing the material undergoing enzymatic hydrolysis in a high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment to obtain a hydrolysate. Specifically, this step further includes the following steps: adding the complex protease: after adjusting the temperature of the material to be hydrolyzed to 50°C and the pH value to 5.5, adding the complex protease to the material to be hydrolyzed, the amount of the complex protease added is 0.1% of the weight ratio of the material to be hydrolyzed; first treatment: the material to be hydrolyzed with the added complex protease is pumped into the high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment, during which enzymatic hydrolysis occurs simultaneously. The pulse frequency of the first pulsed electric field treatment is 20Hz, the electric field strength is 0.1kV / cm, the pulse width is 5μs, and the treatment time is 5min; settling: the material after the first treatment is further hydrolyzed at 50°C for 0.5h to obtain the hydrolysate. Specifically, the complex protease is a combination of flavor protease, bromelain, and papain in a weight ratio of 2:1:1.

[0059] The second processing involves pumping the enzymatic hydrolysate into a high-voltage pulsed electric field treatment chamber for a second pulsed electric field treatment to obtain a semi-finished product. Specifically, in the second processing, the pulse frequency of the second pulsed electric field treatment is 500 Hz, the electric field strength is 1.0 kV / cm, the pulse width is 5 μs, and the treatment time is 10 min.

[0060] The post-processing involves sequentially filtering, purifying, concentrating, and drying the semi-finished product to obtain tilapia flavor base. This step further includes the following steps: filtration, where the semi-finished product is filtered using a ceramic membrane, preferably a 1μm ceramic membrane, to obtain a filtrate; purification, where the filtrate is separated by dextran gel chromatography using a Sephadex G15 column to obtain a purified solution; concentration, where the purified solution is concentrated under vacuum at a temperature of 65°C and a vacuum degree of -0.07 MPa; and drying, where the product obtained after vacuum concentration is dried under vacuum at a temperature of -50°C and a vacuum degree of 1 Pa, resulting in the tilapia flavor base.

[0061] The preparation method of the tilapia flavoring base material for preparing food additives according to Comparative Example 1 of the present invention includes the following steps:

[0062] Prepare materials by collecting the scraps from slaughtered tilapia for later use; preferably, the scraps include the tilapia head, bones, internal organs, scales or skin, and in this embodiment, the scraps weigh 500g.

[0063] The pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Further, the specific operation process of this step includes washing the waste material and crushing it to obtain powder, then mixing the powder with water at a weight ratio of 1:1, and then homogenizing it in a homogenizer at 10000 rpm / min for 1 min to obtain the material to be enzymatically hydrolyzed.

[0064] Enzymatic hydrolysis involves adding a complex protease to the material to be hydrolyzed, and then placing the material undergoing enzymatic hydrolysis in a high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment to obtain the hydrolysate. Specifically, this step further includes the following steps: adding a complex protease: after adjusting the temperature of the material to be hydrolyzed to 50°C and the pH value to 5.5, a complex protease is added to the material to be hydrolyzed, with the amount of the complex protease added being 0.1% of the weight ratio of the material to be hydrolyzed; primary treatment: the material to be hydrolyzed with the added complex protease is pumped into the high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment, during which enzymatic hydrolysis occurs simultaneously. The pulse frequency of the first pulsed electric field treatment is 300Hz, the electric field strength is 1.5kV / cm, the pulse width is 20μs, and the treatment time is 50min; and settling: the material after the first treatment is further hydrolyzed at 50°C for 0.5h to obtain the hydrolysate. Specifically, the complex protease is composed of flavor protease, bromelain, and papain in a weight ratio of 2:1:1.

[0065] The second processing involves pumping the enzymatic hydrolysate into a high-voltage pulsed electric field treatment chamber for a second pulsed electric field treatment to obtain a semi-finished product. Specifically, in the second processing, the pulse frequency of the second pulsed electric field treatment is 500 Hz, the electric field strength is 1.0 kV / cm, the pulse width is 5 μs, and the treatment time is 10 min.

[0066] The post-processing involves sequentially filtering, purifying, concentrating, and drying the semi-finished product to obtain tilapia flavor base. This step further includes the following steps: filtration, where the semi-finished product is filtered using a ceramic membrane, preferably a 1μm ceramic membrane, to obtain a filtrate; purification, where the filtrate is separated by dextran gel chromatography using a Sephadex G15 column to obtain a purified solution; concentration, where the purified solution is concentrated under vacuum at a temperature of 65°C and a vacuum degree of -0.07 MPa; and drying, where the product obtained after vacuum concentration is dried under vacuum at a temperature of -50°C and a vacuum degree of 1 Pa, resulting in the tilapia flavor base.

[0067] The preparation method of the tilapia flavoring base material for preparing food additives according to Comparative Example 2 of the present invention includes the following steps:

[0068] Prepare materials by collecting the scraps from slaughtered tilapia for later use; preferably, the scraps include the tilapia head, bones, internal organs, scales or skin, and in this embodiment, the scraps weigh 500g.

[0069] The pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Further, the specific operation process of this step includes washing the waste material and crushing it to obtain powder, then mixing the powder with water at a weight ratio of 1:1, and then homogenizing it in a homogenizer at 10000 rpm / min for 1 min to obtain the material to be enzymatically hydrolyzed.

[0070] Enzymatic hydrolysis involves adding a complex protease to the material to be hydrolyzed to obtain a hydrolysate. Specifically, this step further includes the following steps: adding the complex protease; adjusting the temperature of the material to be hydrolyzed to 50°C and the pH to 5.5; then adding the complex protease to the material at a weight ratio of 0.1% of the material to be hydrolyzed; hydrolyzing for 4 hours to obtain the hydrolysate. Specifically, the complex protease is composed of flavor protease, bromelain, and papain in a weight ratio of 2:1:1.

[0071] The second processing involves pumping the enzymatic hydrolysate into a high-voltage pulsed electric field treatment chamber for a second pulsed electric field treatment to obtain a semi-finished product. Specifically, in the second processing, the pulse frequency of the second pulsed electric field treatment is 500 Hz, the electric field strength is 1.0 kV / cm, the pulse width is 5 μs, and the treatment time is 10 min.

[0072] The post-processing involves sequentially filtering, purifying, concentrating, and drying the semi-finished product to obtain tilapia flavor base. This step further includes the following steps: filtration, where the semi-finished product is filtered using a ceramic membrane, preferably a 1μm ceramic membrane, to obtain a filtrate; purification, where the filtrate is separated by dextran gel chromatography using a Sephadex G15 column to obtain a purified solution; concentration, where the purified solution is concentrated under vacuum at a temperature of 65°C and a vacuum degree of -0.07 MPa; and drying, where the product obtained after vacuum concentration is dried under vacuum at a temperature of -50°C and a vacuum degree of 1 Pa, resulting in the tilapia flavor base.

[0073] The preparation method of the tilapia flavoring base material for preparing food additives according to Comparative Example 3 of the present invention includes the following steps:

[0074] Prepare materials by collecting the scraps from slaughtered tilapia for later use; preferably, the scraps include the tilapia head, bones, internal organs, scales or skin, and in this embodiment, the scraps weigh 500g.

[0075] The pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Further, the specific operation process of this step includes washing the waste material and crushing it to obtain powder, then mixing the powder with water at a weight ratio of 1:1, and then homogenizing it in a homogenizer at 10000 rpm / min for 1 min to obtain the material to be enzymatically hydrolyzed.

[0076] Enzymatic hydrolysis involves adding a complex protease to the material to be hydrolyzed to obtain a hydrolysate. Specifically, this step further includes the following steps: adding the complex protease; adjusting the temperature of the material to be hydrolyzed to 50°C and the pH to 5.5; then adding the complex protease to the material at a weight ratio of 0.1% of the material to be hydrolyzed; hydrolyzing for 4 hours to obtain the hydrolysate. Specifically, the complex protease is composed of flavor protease, bromelain, and papain in a weight ratio of 2:1:1.

[0077] Post-processing involves filtering and purifying the enzymatic hydrolysate, followed by vacuum compression. The vacuum-compressed product is then vacuum-dried to obtain the tilapia flavor base. This step also includes the following steps: filtration, where the enzymatic hydrolysate is filtered through a ceramic membrane (preferably a 1μm membrane) to obtain a filtrate; purification, where the filtrate is separated by dextran gel chromatography (Sephadex G15 column chromatography) to obtain a purified solution; concentration, where the purified solution is vacuum-concentrated at 65°C and a vacuum degree of -0.07 MPa; and drying, where the product obtained after vacuum concentration is vacuum-dried at -50°C and a vacuum degree of 1 Pa. After vacuum drying, the tilapia flavor base is obtained.

[0078] The preparation method of the tilapia flavoring base material for preparing food additives according to Comparative Example 4 of the present invention includes the following steps:

[0079] Prepare materials by collecting the scraps from slaughtered tilapia for later use; preferably, the scraps include the tilapia head, bones, internal organs, scales or skin, and in this embodiment, the scraps weigh 500g.

[0080] The pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Further, the specific operation process of this step includes washing the waste material and crushing it to obtain powder, then mixing the powder with water at a weight ratio of 1:1, and then homogenizing it in a homogenizer at 10000 rpm / min for 1 min to obtain the material to be enzymatically hydrolyzed.

[0081] Enzymatic hydrolysis involves adding a complex protease to the material to be hydrolyzed, and then placing the material undergoing enzymatic hydrolysis in a high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment to obtain the hydrolysate. Specifically, this step also includes the following steps: adding a complex protease: after adjusting the temperature of the material to be hydrolyzed to 50°C and the pH value to 5.5, a complex protease is added to the material to be hydrolyzed, with the amount of the complex protease added being 0.1% of the weight ratio of the material to be hydrolyzed; primary treatment: the material to be hydrolyzed with the added complex protease is pumped into the high-voltage pulsed electric field treatment chamber for a first pulsed electric field treatment, during which enzymatic hydrolysis occurs simultaneously. The pulse frequency of the first pulsed electric field treatment is 50Hz, the electric field strength is 0.5kV / cm, the pulse width is 10μs, and the treatment time is 20min; and settling: the material after the first treatment is further hydrolyzed at 50°C for 0.5h to obtain the hydrolysate. Specifically, the complex protease is composed of flavor protease, bromelain, and papain in a weight ratio of 2:1:1.

[0082] Post-processing involves filtering and purifying the enzymatic hydrolysate, followed by vacuum compression. The vacuum-compressed product is then vacuum-dried to obtain the tilapia flavor base. This step also includes the following steps: filtration, where the enzymatic hydrolysate is filtered through a ceramic membrane (preferably a 1μm membrane) to obtain a filtrate; purification, where the filtrate is separated by dextran gel chromatography (Sephadex G15 column chromatography) to obtain a purified solution; concentration, where the purified solution is vacuum-concentrated at 65°C and a vacuum degree of -0.07 MPa; and drying, where the product obtained after vacuum concentration is vacuum-dried at -50°C and a vacuum degree of 1 Pa. After vacuum drying, the tilapia flavor base is obtained.

[0083] A unified performance evaluation was conducted on the above 5 embodiments and 3 comparative examples, including the following evaluations:

[0084] 1. Determination of amino acid nitrogen

[0085] The tilapia flavoring base materials prepared in Examples 1-5 and Comparative Examples 1-3 were dissolved in water to prepare solutions of 1 mg / mL. The total nitrogen content in the protein hydrolysates was determined by the Kjeldahl method, and the amino nitrogen content in the protein hydrolysates was determined by formaldehyde titration (GB5009.235-2016).

[0086] 2. Analysis of umami peptide content

[0087] The tilapia flavor base materials prepared in Examples 1-5 and Comparative Examples 1-3 were dissolved in water to prepare solutions of 1 mg / mL. The peptide distribution in each solution was tested according to Appendix A of GB / T 22492-2008, using GPC / UV. Based on the peptide distribution test results, the mass percentage of peptides with molecular weights of 200 Da to 1000 Da in the total peptides was calculated and denoted as "umami peptide percentage (200 Da to 1000 Da)", which was used to measure the umami peptide content in the supernatant of the enzymatic hydrolysis final product.

[0088] 3. Sensory evaluation

[0089] Sensory analysis was conducted using a scoring method to assess fishy, ​​umami, and bitter tastes. The scoring criteria for the three sensory components are shown in the table below.

[0090] The results of the above performance evaluation are shown in the table below:

[0091] amino acid nitrogen g / 100g Umami peptide ratio Sensory evaluation Example 1 0.47 63% No fishy or bitter taste, but rich in umami flavor. Example 2 0.52 67% No fishy or bitter taste, but rich in umami flavor. Example 3 0.49 65% No fishy or bitter taste, but rich in umami flavor. Example 4 0.31 54% It has a slightly fishy smell, no bitterness, and a rich umami flavor. Comparative Example 1 0.22 37% It has a slightly fishy smell, a slightly bitter taste, and a mild umami flavor. Comparative Example 2 0.25 40% It has a distinct fishy smell, a slightly bitter taste, and a weak umami flavor. Comparative Example 3 0.24 38% It has a distinct fishy smell, a slightly bitter taste, and a weak umami flavor. Comparative Example 4 0.37 52% It has no fishy smell, a slightly bitter taste, and a distinct umami flavor.

[0092] As shown in the table above, combined high-voltage pulsed electric field treatment significantly improves the amino acid nitrogen content and umami peptide content of the obtained tilapia flavor base, with the umami peptide content increasing to over 60%. Furthermore, changing the high-voltage pulsed electric field parameters also significantly affects the umami peptide content and amino acid nitrogen content. This is because the pulsed electric field influences the enzyme molecule conformation, thereby affecting protein hydrolysis through its enzyme activity.

[0093] As can be seen from Examples 1-4 and Comparative Examples 1-4, if the pulse frequency, electric field strength, pulse width, and treatment time of the first high-voltage pulsed electric field treatment are too long, the proportion of umami peptides and amino acid nitrogen in the product will decrease. This may be because the pulsed electric field treatment leads to a decrease in enzyme activity and inhibits the enzymatic hydrolysis effect.

[0094] The tilapia flavor base prepared in this application has a strong umami flavor and few undesirable flavors such as fishiness and bitterness. This indicates that the enzymatic hydrolysis using a high-voltage pulsed electric field combined with a complex protease can effectively increase the yield of polypeptides with a molecular weight of 200-1000 Daltons from tilapia by-products, thereby obtaining richer short-chain proteins and amino acids and other umami substances. This significantly increases the content of umami peptides in the enzymatic hydrolysis products, improves the undesirable sensory properties of fish flavor base prepared from tilapia by-products, and makes the obtained flavor base have a prominent umami flavor, a full flavor, and be healthy and safe.

[0095] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the inventive concept, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a tilapia flavoring base, characterized in that, Includes the following steps: Prepare the ingredients, collecting the scraps from the slaughtered tilapia for later use; Pretreatment involves washing the waste material and then homogenizing it to obtain the material to be enzymatically hydrolyzed. Enzymatic hydrolysis is performed by adjusting the temperature of the material to be hydrolyzed to 50–60°C and the pH to 5.5–7.5, then adding a complex protease to the material at a concentration of 0.1–0.8% of the weight of the material. The material containing the complex protease is then pumped into a high-voltage pulsed electric field treatment chamber for the first pulsed electric field treatment, during which enzymatic hydrolysis occurs simultaneously. The pulse frequency of the first pulsed electric field treatment is 50–200 Hz, the electric field strength is 0.5–1.0 kV / cm, the pulse width is 10–15 μs, and the treatment time is 20–40 min. The treated material is then allowed to stand at 50–60°C and enzymatic hydrolysis continues for 0.5–1 h to obtain the enzymatic hydrolysate. The second processing involves pumping the enzymatic hydrolysate into a high-voltage pulsed electric field treatment chamber for a second pulsed electric field treatment. In the second processing, the pulse frequency of the second pulsed electric field treatment is 500–1000 Hz, the electric field strength is 1.0–4.0 kV / cm, the pulse width is 5–20 μs, and the treatment time is 10–30 min, to obtain a semi-finished product. The semi-finished product is then subjected to filtration, purification, concentration, and drying to obtain tilapia flavor base.

2. The method for preparing the tilapia flavoring base according to claim 1, characterized in that: The complex protease is composed of flavor protease, bromelain, and papain in a weight ratio of (2-5): (1-3): (1-3).

3. The method for preparing tilapia flavoring base according to claim 1, characterized in that, The preprocessing steps include: The waste material is washed and crushed to obtain powder. The powder is mixed with water at a weight ratio of 1:1 to 1.5 and then homogenized in a homogenizer at 10,000 to 15,000 rpm for 1 to 5 minutes to obtain the material to be enzymatically hydrolyzed.

4. The method for preparing tilapia flavoring base according to claim 1, characterized in that, The post-processing steps include the following steps: Filtration: The semi-finished product is filtered using a ceramic membrane to obtain a filtrate. Purification: The filtrate was subjected to dextran gel chromatography to obtain a purified solution. Concentration: The purified solution is concentrated under vacuum at a temperature of 65–85°C and a vacuum degree of -0.07–-0.1 MPa. Drying: The product obtained after vacuum concentration is subjected to vacuum drying at a temperature of -50 to -80°C and a vacuum degree of 1 to 50 Pa. After vacuum drying, the tilapia flavor base is obtained.

5. The method for preparing tilapia flavoring base according to any one of claims 1-4, characterized in that: The waste materials include tilapia heads, bones, viscera, scales, or skin.

6. A tilapia flavoring base, characterized in that: It is prepared by the preparation method described in any one of claims 1 to 5.

7. The tilapia flavoring base according to claim 6, characterized in that: The tilapia flavoring base is used to prepare food additives.