Hypoallergenic silver fish meal and preparation method thereof

Abstract

The invention discloses hypoallergenic silver fish meal and a preparation method thereof, and belongs to the technical field of functional foods.The hypoallergenic silver fish meal is obtained by adding pretreated whitebait into a reducing sugar solution to be soaked, drying, smashing and sieving the whitebait after soaking, and the hypoallergenic silver fish meal is obtained by conducting a Maillard reaction on the whitebait. The content of a sensitization marker parvalbumin is reduced by more than 60% compared with that of the silver fish meal which is not treated by the Maillard reaction.

Description

Technical Field

[0001] The invention belongs to the technical field of functional foods, and particularly relates to low-allergenic whitebait powder and a preparation method thereof. Background Art

[0002] A large number of epidemiological surveys have shown that the prevalence of food allergies is increasing, especially among children and infants. Allergies to fish are also associated with allergic rhinitis, childhood bronchial asthma, and even gastric polyps.

[0003] In addition to strict dietary control, food allergies can also be controlled and treated through dietary therapy to induce tolerance and enhance the body's adaptation to the outside world. Therefore, the emergence of low-allergenic products can help allergy patients gradually treat food allergies using dietary therapy.

[0004] Because whitebait is delicious and high in protein and calcium, some domestic processing companies and families simply process whitebait into whitebait powder as baby food and food for the middle-aged and elderly. However, some people experience allergic symptoms such as rashes, vomiting, sore throat, and asthma after eating whitebait. The presence of allergens not only limits the audience range of whitebait products, but may also pose a threat to the health of certain groups of people.

[0005] Therefore, it is necessary to treat whitebait as a food to reduce allergens such as PV. A large number of studies have shown that the Maillard reaction can reduce allergenicity while giving food a unique flavor, but there are few studies on the Maillard reaction of intact aquatic products. Generally, the Maillard reaction is performed on minced meat to reduce allergenicity. Research on intact aquatic products treated with the Maillard reaction will help the development of reducing allergenicity of small aquatic products. Summary of the invention

[0006] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0008] Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide a low-allergenic silverfish powder, wherein the low-allergenic silverfish powder is prepared by Maillard reaction of silverfish, and the content of the allergenic marker parvalbumin is reduced by more than 60% compared with the silverfish powder not treated with Maillard reaction.

[0009] Another object of the present invention is to provide a method for preparing low-allergenic whitebait powder. To solve the above technical problems, the present invention provides the following technical solutions: comprising:

[0010] The pretreated whitebait is added into reducing sugar solution and soaked, and then dried, crushed and sieved to obtain low-allergenic whitebait powder.

[0011] As a preferred embodiment of the method for preparing the low-allergenic whitebait powder of the present invention, the pretreatment of the whitebait is to wash and drain the whitebait.

[0012] As a preferred embodiment of the method for preparing the low-allergenic whitebait powder of the present invention, the reducing sugar in the reducing sugar solution is xylose.

[0013] As a preferred solution of the method for preparing the low-allergenic silverfish powder of the present invention, the concentration of the reducing sugar solution is 0.6-0.8%.

[0014] As a preferred solution of the method for preparing the low-allergenic silverfish powder of the present invention, the soaking time is 30 to 90 minutes.

[0015] As a preferred embodiment of the method for preparing the low-allergenic silverfish powder of the present invention, the drying time is 30 to 60 minutes.

[0016] As a preferred embodiment of the method for preparing the low-allergenic whitebait powder of the present invention, the solid-liquid ratio of the pretreated whitebait to the reducing sugar solution is 1:5-8.

[0017] As a preferred embodiment of the method for preparing the low-allergenic silverfish powder of the present invention, the pulverizing and screening is performed through a 60-100 mesh sieve.

[0018] Beneficial effects of the present invention:

[0019] (1) Through the Maillard reaction treatment, the content of parvalbumin, an allergenic marker, in whitebait meal was reduced by more than 60%, thereby significantly reducing the allergenicity of the product.

[0020] (2) Due to the reduced allergenicity, this low-allergenic whitebait powder can be more safely used in various foods, especially those that require strict control of allergens, which helps meet the growing demand for low-allergenic foods in the market. This product helps to improve the overall food safety and reduce health problems caused by food allergies.

[0021] (3) In addition, for patients with food allergies, in addition to strict dietary control, diet therapy is also an effective means of control and treatment. This low-allergenic whitebait powder can be used as part of diet therapy to help patients gradually build tolerance to allergens such as whitebait. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0023] Figure 1 The actual picture of whitebait powder of Example 1 and Comparative Example 1 of the present invention

[0024] Figure 2 The electrophoresis diagrams of the extracts of Example 1 and Comparative Examples 1 and 2 of the present invention are shown.

[0025] Figure 3 This is a physical picture of whitebait powder obtained by treating with different types of reducing sugars in Example 2 of the present invention.

[0026] Figure 4 This is the electrophoresis diagram of the whitebait powder extract obtained by treating with different types of reducing sugars in Example 2 of the present invention.

[0027] Figure 5 This is a physical picture of whitebait powder obtained by treating with different xylose concentrations in Example 3 of the present invention.

[0028] Figure 6 This is a physical picture of the whitebait powder obtained by soaking the whitebait powder in a xylose solution for different time periods according to Example 4 of the present invention.

[0029] Figure 7 This is a physical picture of the whitebait powder obtained by treating the whitebait powder under different drying temperature conditions in Example 5 of the present invention.

[0030] Figure 8 This is a physical picture of the whitebait powder processed under different drying time conditions in Example 6 of the present invention. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0032] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0033] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0034] Unless otherwise specified, the raw materials used in the present invention are all commercially available in the art.

[0035] The sensitization of the products of various examples and comparative examples in the present invention was evaluated by the following method.

[0036] 1. Browning degree

[0037] Take 200 μL of the supernatant after centrifugation and put it into a 96-well plate, place the 96-well plate in an ELISA reader, and measure its absorbance at 294 nm and 420 nm.

[0038] 2.SDS-PAGE

[0039] Take 20 μL of silverfish powder extract and add it to 5 μL of 4× protein loading buffer, and heat it at 100℃ for 5 minutes. Load the sample with 15% Tris-gly precast gel, electrophoresed at 150V constant voltage for 1 hour, stained with Coomassie brilliant blue for 20 minutes, destained and photographed with gel imager. Use prestained protein standards to estimate the molecular weight of small albumin in the sample.

[0040] 3. Allergenicity Assessment

[0041] Use fish parvalbumin double antibody sandwich ELISA kit

[0042] Set up blank wells (blank control wells without samples and enzyme-labeled reagents, and the rest of the steps are the same), standard wells, and blank wells for the samples to be tested. Accurately add 50μL of the standard sample to the enzyme-labeled plate, add 40μL of the sample diluent to the sample wells to be tested, and then add 10μL of the sample to be tested. Gently shake to mix. Seal the plate with a sealing film and incubate at 37 for 30 minutes. Carefully peel off the sealing film, discard the liquid, spin dry, fill each well with washing solution, let it stand for 30 seconds and discard it, repeat 5 times, and pat dry. Add 50μL of enzyme-labeled reagent to each well, except the blank well, seal the plate with a sealing film and incubate at 37 for 30 minutes. Carefully peel off the sealing film, discard the liquid, spin dry, fill each well with washing solution, let it stand for 30 seconds and discard it, repeat 5 times, and pat dry. First add 50μL of color developer A to each well, then add 50μL of color developer B, gently shake and mix, and color at 37 for 10 minutes in the dark. Finally, add 50 μL of stop solution to each well, adjust to zero with the blank well, measure the absorbance at 450 nm, and calculate the parvalbumin dry basis content according to the standard curve.

[0043] Reduction rate = (1-M / M0) × 100%

[0044] M0-Example 1 parvalbumin dry basis content

[0045] M- parvalbumin dry content of the sample to be tested

[0046] Example 1

[0047] This embodiment provides a method for reducing the allergenicity of whitebait powder, specifically:

[0048] After washing and draining the whitebait, add it into a 0.6% D-xylose solution and soak it at 4°C for 1 hour, wherein 300 mL of D-xylose solution is used for every 60 g of whitebait (the material-liquid ratio is 1:5);

[0049] After soaking, the mixture is dried at 120° C. for 30 minutes until the moisture content is less than 14%, and then the mixture is crushed and passed through a 60-mesh sieve to obtain low-allergenic whitebait powder.

[0050] Comparative Example 1

[0051] The difference between this comparative example and Example 1 is that the D-xylose solution is adjusted to distilled water, and the remaining steps and processes are all referred to Example 1 to obtain the whitebait powder of this comparative example.

[0052] The color of the whitebait powder obtained by comparing Example 1 and Comparative Example 1 is as follows Figure 1 As shown, Figure 1 The results showed that the color of the whitebait powder extract after soaking in D-xylose increased significantly when the treatment conditions were 120℃ and 30min, which indicated the occurrence of Maillard reaction.

[0053] Comparative Example 2

[0054] After washing and draining, the whitebait was added into Tris-HCl buffer solution with pH 7.4 at a solid-liquid ratio of 1:3, homogenized and extracted for 3 h, centrifuged at 8000 rpm / min for 20 min at 4 °C, and the supernatant after centrifugation was used for browning, gel electrophoresis and ELISA analysis.

[0055] Taking the parvalbumin dry content measured in this comparative example as a benchmark, since the parvalbumin concentration measured by the ELISA double antibody sandwich method is related to its immune activity, and this comparative example has not been processed and does not affect the immune activity of parvalbumin, the sensitization under this comparative example is defined as 100%.

[0056] The extracts of Example 1 and Comparative Examples 1 and 2 were subjected to SDS-PAGE test, and the results were as follows: Figure 2 As shown, Figure 2It is shown that the electrophoresis bands of Comparative Example 1 and Example 1 are significantly reduced compared with Comparative Example 2. After drying at 120°C for 30 minutes, the protein electrophoresis bands of Example 1 soaked with xylose are less than those of Comparative Example 1 soaked without xylose, and the bands of Example 1 near 12 kDa are significantly lighter than those of Comparative Example 1. This result shows that high temperature treatment may change the structure of protein, thereby causing changes in its properties, such as changes in hydrophobicity, so that the types of proteins extracted by Comparative Example 1 and Example 1 are less than those of Comparative Example 2 after the same extraction method; moreover, glycosylation treatment will also change the structure of protein, thereby causing changes in its properties, so that the bands near 12 kDa of the whitebait powder extract after D-xylose soaking treatment are lighter in color than those of the untreated whitebait powder extract.

[0057] The changes in sensitization and absorbance of the products of Example 1, Comparative Example 1 and Comparative Example 2 are shown in Table 1.

[0058] Table 1

[0059]

[0060] As can be seen from Table 1, the content of parvalbumin in the extract after treatment at 120°C for 30 minutes was significantly reduced. The parvalbumin content of the whitebait powder extract soaked in 0.6% D-xylose was reduced by 65.32%, and the parvalbumin content of the whitebait powder extract not soaked in 0.6% D-xylose was reduced by 52.66%. This indicates that high temperature may change the structure of parvalbumin, thereby changing the site where PV binds to antibodies, resulting in a decrease in its immune binding activity, reducing its sensitization, and thus reducing the measured parvalbumin content. After soaking in 0.6% D-xylose, the Maillard reaction can occur at high temperature, and glycosylation modification can be carried out, thereby changing the structure of parvalbumin, reducing its immune binding activity, and further reducing its sensitization, so that the measured parvalbumin content is lower.

[0061] Example 2

[0062] This example is used to explore the effect of reducing sugar types on the processing effect of whitebait powder. The difference from Example 1 is that the types of reducing sugars are adjusted to glucose, galactose, fructose, and lactose, respectively. The remaining steps and processes are all referred to Example 1 to obtain whitebait powder treated with different types of reducing sugar solutions in this example. The relevant characterization properties are tested on the whitebait powder. The results are as follows: Figure 3 and Figure 4 shown.

[0063] Figure 3 These are actual pictures of whitebait powder treated with different types of reducing sugar solutions. The results show that lactose has the lightest color, indicating that the degree of Maillard reaction after lactose treatment is lower.

[0064] Figure 4 This is the SDS-PAGE test result diagram. It can be seen that the protein composition of silverfish powder treated with reducing sugar has changed compared with that of fresh silverfish. Proteins larger than 55kDa in the initial extract of silverfish powder after Maillard reaction are not shown in the electrophoresis diagram, indicating that the Maillard reaction may have changed the structure of these proteins, thereby changing the properties of these proteins, such as changes in surface hydrophobicity; therefore, these proteins cannot be extracted by the same treatment method, and there are no bands of this part of the protein on the electrophoresis. It can be seen from the figure that, except for lactose treatment, the color of the bands near 10kDa of proteins treated with other reducing sugars has obviously become lighter.

[0065] The allergenicity and absorbance of different products in Example 2 were measured and compared with those in Example 1. The results are shown in Table 2.

[0066] Table 2

[0067]

[0068] As can be seen from Table 2, the reduction rate of parvalbumin is xylose>glucose>galactose>fructose>lactose, and the absorbance at 294nm can indicate the content of colorless intermediates produced by the Maillard reaction, and the absorbance at 420nm indicates the degree of browning, so the absorbance values ​​at 294nm and 420nm can be used to monitor the progress and degree of the Maillard reaction. From the results, it can be seen that the absorbance values ​​at 294nm are xylose>fructose>glucose>galactose>lactose from large to small; in addition, the absorbance values ​​at 420nm are xylose>galactose>glucose≈fructose>lactose from large to small. Therefore, the Maillard reaction of whitebait powder treated with D-xylose progresses fastest and has the highest degree of browning, while the Maillard reaction of whitebait powder treated with D-lactose progresses slowest and has the lowest degree of browning. That is, the reaction degree of xylose is higher, so its reduction rate is also higher

[0069] Example 3

[0070] This example is used to explore the effect of xylose concentration on the processing effect of whitebait powder. The difference from Example 1 is that the concentrations of D-xylose solution are adjusted to 0.2%, 0.4%, 0.6% (Example 1), 0.8%, and 1.0%, respectively. The remaining steps and processes are all referred to Example 1 to obtain whitebait powder treated with reducing sugar solutions of different concentrations in this example. The relevant characterization properties are tested on the whitebait powder. The results are as follows: Figure 5 And as shown in Table 3.

[0071] Table 3

[0072]

[0073] Figure 5 The actual picture of whitebait powder treated with reducing sugar solutions of different concentrations. The results show that as the xylose concentration increases, the color of the whitebait powder also increases, indicating that the reducing sugar concentration will affect the degree of glycosylation reaction.

[0074] From the absorbance results at 294 nm in Table 3, it can be seen that as the xylose concentration increases, the absorbance of the intermediate product will also increase, and the absorbance of the intermediate product increases the most when the xylose concentration increases from 0.2% to 0.4%; however, the browning degree changes the most when it increases from 0.6% to 0.8%, indicating that when the xylose concentration is low, the reaction may be in the intermediate stage. The proportion will be higher, and as the concentration increases, it may promote the completion of the reaction, thereby increasing the production of melanin, leading to an increase in the degree of browning.

[0075] In addition, the percentage of PV content reduction increases with the increase of xylose concentration, but begins to stabilize after reaching 0.6%. At this time, the change of xylose concentration has little effect on the Maillard reaction. The sites that can undergo glycosylation may have already reacted, and there are no vacant sites that can continue to provide for the occurrence of the Maillard reaction. In summary, when the xylose concentration is in the range of 0.6-0.8%, it has a good effect on reducing color, Maillard reaction degree and IgG binding ability.

[0076] Example 4

[0077] This example is used to explore the effect of the soaking time of whitebait in xylose solution on the processing effect of whitebait. The difference from Example 1 is that the soaking time is adjusted to 0.5h, 1h (Example 1), 1h, 2h, and 2.5h, respectively. The remaining steps and processes are all referred to Example 1 to obtain whitebait powder with different soaking treatment times in this example, and relevant characterization properties are tested on it. The results are as follows: Figure 6 And as shown in Table 4.

[0078] Table 4

[0079]

[0080] like Figure 6 As shown, the change in the color of whitebait pink with soaking time is not very obvious.

[0081] As can be seen from Table 4, the effect of immersion time on the absorbance at 294nm and 420nm is not very obvious. It first increases slowly and then tends to be stable. This may be because the fish body is small and soaking for half an hour can allow the reducing sugar content in the fish to reach a high level, so the extension of the soaking time has little effect on the degree of Maillard reaction.

[0082] From Table 4, as the soaking time increases, the percentage of PV content reduction first increases and then decreases, indicating that the IgG binding capacity of PV first decreases and then increases with the soaking time, and reaches the lowest value when the soaking time is 1 hour. It may be because the increase in soaking time will cause the water-soluble parvalbumin to dissolve in the soaking solution, thereby reducing the parvalbumin content in the extract.

[0083] In summary, the soaking time of 1 to 1.5 hours has a better effect on the reduction of color, Maillard reaction degree and IgG binding ability.

[0084] Example 5

[0085] This embodiment is used to explore the influence of different drying temperatures on the processing effect of whitebait powder. The difference from Example 1 is that the drying temperatures are adjusted to 80°C, 100°C, 120°C (Example 1), 140°C, and 160°C, respectively. The remaining steps and processes are all referred to Example 1 to obtain whitebait powder at different drying temperatures in this embodiment, and relevant characterization properties are tested on it. The results are as follows Figure 7 And shown in Table 5.

[0086] Table 5

[0087]

[0088] from Figure 7 It can be seen that the increase in drying temperature will lead to a darker color of whitebait powder.

[0089] It can be seen from Table 5 that the absorbance of the intermediate product and browning also increases first and then decreases with the increase of drying temperature, and the absorbance reaches the maximum value when the drying temperature reaches 120°C. In addition, from the reduction rate of small albumin in Table 5, as the drying temperature increases, the reduction first increases and then tends to be flat. In short, the drying temperature has a great influence on the color change, Maillard reaction degree and PV reduction rate of whitebait powder processing.

[0090] Example 6

[0091] The present embodiment is used to explore the influence of different drying times on the processing effect of whitebait powder. The difference from Example 1 is that the drying times are adjusted to 15min, 30min, 45min, 60min, and 75min respectively. The remaining steps and processes are all referred to Example 1 to obtain whitebait powder under different drying times of the present embodiment, and relevant characterization properties are tested on it. The results are as follows: Figure 8 And shown in Table 6.

[0092] Table 6

[0093]

[0094]

[0095] like Figure 8 As shown in the figure, the increase of drying time will lead to the darkening of the color of whitebait powder, but the increase is relatively small.

[0096] From the reduction rate in Table 6, the reduction rate of small albumin first increases and then decreases with the increase of drying time; the absorbance of the intermediate product and the browning degree is the largest when the drying time reaches 30 minutes, and then first decreases and then increases.

[0097] In summary, the present invention discloses a low-allergenic silverfish powder and a preparation method thereof. The pretreated silverfish is added to a reducing sugar solution for soaking, and the solution is dried and crushed and sieved after soaking. The low-allergenic silverfish powder obtained has a content of the allergenic marker parvalbumin reduced by more than 60% compared with the silverfish powder not treated with the Maillard reaction.

[0098] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A hypoallergenic whitebait powder, characterized in that: The low-allergenic whitebait meal is prepared by subjecting whitebait to the Maillard reaction, and the content of the allergenic marker parvalbumin is reduced by more than 60% compared with whitebait meal that has not been processed by the Maillard reaction.

2. The method for preparing hypoallergenic whitebait powder according to claim 1, wherein: include, The pretreated whitebait is added into reducing sugar solution and soaked, and then dried, crushed and sieved to obtain low-allergenic whitebait powder.

3. the method for reducing the sensitization of whitebait powder as claimed in claim 2, is characterized in that: The pretreatment of the whitebait is to clean and drain the whitebait.

4. the method for reducing the sensitization of whitebait powder as claimed in claim 2, is characterized in that: The reducing sugar in the reducing sugar solution is xylose.

5. The method for reducing the allergenicity of whitebait powder as claimed in claim 4, wherein: The concentration of the reducing sugar solution is 0.6-0.8%.

6. The method for reducing the allergenicity of whitebait powder as claimed in claim 2, wherein: The soaking time is 30 to 90 minutes.

7. The method for reducing the allergenicity of whitebait powder as claimed in claim 2, wherein: The drying temperature is 100-140°C.

8. The method for reducing the allergenicity of whitebait powder as claimed in claim 7, wherein: The drying time is 30 to 60 minutes.

9. The method for reducing the allergenicity of whitebait powder as claimed in any one of claims 4 and 5, wherein: The material-liquid ratio of the pretreated whitebait to the reducing sugar solution is 1:5-8.

10. The method for reducing the allergenicity of whitebait powder as claimed in claim 2, wherein: The crushing and screening is through a 60-100 mesh sieve.

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