Method for removing fishy smell of fish scale collagen peptide based on glycosylation modification

Abstract

The invention discloses a method for removing fishy smell of fish scale collagen peptide based on glycosylation modification, and belongs to the technical field of biological polysaccharide utilization. The collagen peptide is modified through galactooligosaccharide glycosylation, so that fishy smell substances, especially aldehyde compounds, of the collagen peptide are reduced, the variety of volatile compounds of the collagen peptide is enriched, and the sensory characteristics of the collagen peptide are improved. Therefore, a glycosylated collagen peptide product with relatively low fishy smell and bitter taste and relatively good flavor can be obtained by utilizing the method, and meanwhile, the preparation method disclosed by the invention is few in influence factors, high in repeatability, high in reproducibility, simple in preparation method and suitable for industrial batch production.

Description

Technical Field

[0001] The invention belongs to the technical field of biopolysaccharides, and particularly relates to a method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification, so as to improve its application value in the food industry. Background Art

[0002] As a protein source with high nutritional value, aquatic collagen peptides have received widespread attention in the food and beauty fields in recent years. These collagen peptides are mainly obtained from fish skin, fish bones, fish scales and other processing by-products of aquatic organisms through enzymatic hydrolysis. Compared with collagen peptides extracted from terrestrial animals such as pigs, cattle and other livestock and poultry, aquatic collagen peptides have the advantages of low antigenicity and low allergy, which makes them have a wider application prospect in the edible and medicinal fields. However, aquatic collagen peptides often have a fishy smell during the extraction and processing process. This fishy smell mainly comes from aldehydes, ammonia and other substances. These substances are difficult to completely remove during the processing process, which seriously affects the flavor of collagen peptide drinks and consumer acceptance, and greatly limits the application of collagen peptides in the food industry, especially when used as oral beauty products, the flavor problem is particularly important.

[0003] Traditional methods of removing fishy smell include adsorption and adding yeast extract. The former uses activated carbon to remove aldehydes and ketones, while the latter masks the fishy smell by increasing the content of aromatic compounds. Although the above methods can reduce the fishy smell of collagen peptides to a certain extent, they also have certain limitations. The adsorption method may remove too many effective ingredients, affecting the nutrition and function of the product; although adding yeast extract can mask the fishy smell, it may change the original flavor of the product.

[0004] The Maillard reaction is a non-enzymatic browning reaction. It forms a cross-linked modified product through a carbonyl-amine condensation reaction between proteins or polypeptides and sugars. It can produce a variety of flavor compounds, including reductones, aldehydes, and heterocyclic compounds, which can mask or neutralize the fishy smell of proteins or polypeptides themselves. Existing research CN102726697B "A method for preparing a water-soluble Maillard reaction-type food flavor" is based on the Maillard reaction product. By optimizing the process flow, a Maillard reaction-type food flavor is prepared, which improves the application of Maillard reaction-type food flavors in the food industry. CN118044591A "A method for removing the fishy smell of beef tendon based on the Maillard reaction" prepares the Maillard reaction product of enzymatic beef tendon and finds that the Maillard reaction can effectively improve the fishy smell of beef tendon, achieve the deodorization and fragrance enhancement of beef tendon, and increase the market value of beef tendon.

[0005] Therefore, developing a new method that can effectively remove the fishy smell while maintaining or enhancing the flavor of collagen peptides is of great significance to improving the market competitiveness and consumer acceptance of collagen peptide drinks. Summary of the invention

[0006] The purpose of the present invention is to provide a method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification, so as to improve its flavor and enhance its application value in the food industry.

[0007] The principle of the present invention is to improve the flavor of collagen peptides by glycosylation modification and the principle of Maillard reaction, so as to achieve the effect of removing the fishy smell and enhancing the flavor. Specifically, galacto-oligosaccharides are used to carry out glycosylation reaction with collagen peptides. Galacto-oligosaccharides are a kind of functional oligosaccharides with natural properties. Their molecular structure is generally 1 to 7 galactose groups connected to galactose or glucose molecules, which is conducive to glycosylation reaction with peptide fishy smell. In addition, the present invention selects galacto-oligosaccharides because of their stable structure and strong acid resistance and heat resistance.

[0008] First, the present invention provides a method for extracting collagen peptides from fish scales, which specifically comprises the following steps:

[0009] a. Put the fish scales into an enzymatic hydrolysis tank at pH 12, bubble and saponify for 40 minutes, and rinse with pure water at pH 7;

[0010] b. Raise the water temperature to 95°C and keep it warm for 1 hour for pyrolysis, stirring and bubbling during the process;

[0011] c. Cool the water to 56°C, add alkaline protease for 30 minutes, then add neutral protease for 1.5 hours, and finally add flavor protease for 1 hour; heat to 100°C and keep for 10 minutes to inactivate the enzyme;

[0012] d. Stir the liquid in the decolorization tank evenly, add activated carbon and perlite to keep the temperature at 65℃, and stir and decolorize for 30 minutes;

[0013] e. Filter through the frame until it is clear, the sample is light yellow, transparent, and free of impurities; the smell has the unique smell of collagen;

[0014] f. The filtered solution is spray-dried to obtain enzymatically hydrolyzed fish scale collagen peptides.

[0015] Furthermore, the amount of fish scale added in step a is 300-500 g added to 3500-5000 mL of water.

[0016] Furthermore, the enzyme addition amount in step c is 2.5-5 g alkaline protease, 1-2 g neutral protease and 0.6-1.2 g flavor protease.

[0017] Furthermore, the amount of activated carbon added in step d is 80-120 g, and the amount of perlite added is 20-25 kg.

[0018] Furthermore, the fish scale collagen peptide prepared above is modified by glycosylation to remove the fishy smell of the fish scale collagen peptide, and the method comprises the following steps:

[0019] a. Dissolve fish scale collagen peptide in buffer, add galacto-oligosaccharide in a certain proportion, and stir to mix;

[0020] b. heating the mixed sample at a suitable temperature for a certain period of time;

[0021] c. After the heated sample is concentrated and dried, a glycosylated fish scale collagen peptide product is obtained.

[0022] Furthermore, the fish scale collagen peptide in step a is derived from one or more of grass carp, silver carp, tilapia or low-value marine fish, and has a molecular weight distribution of about 1500-2000 Da.

[0023] Furthermore, the purity of the galacto-oligosaccharide in step a is 80% to 82%.

[0024] Furthermore, the amount of fish scale collagen peptide added in step a is 1% to 3%, and the amount of galacto-oligosaccharide added is 4% to 12%.

[0025] Furthermore, the heating temperature in step b is 100° C. and the heating time is 20 to 60 minutes.

[0026] Furthermore, the buffer in step a is a 50-100 mM phosphate buffer solution with a pH of 8.0-8.5.

[0027] Furthermore, the heating conditions in step b simulate low glycosylation degree heating conditions and industrial thermal sterilization treatment conditions.

[0028] Furthermore, the drying in step c is vacuum freeze drying.

[0029] The invention provides a glycosylation-modified fish scale collagen peptide product prepared by the method.

[0030] In addition, the present invention also provides the use of the fish scale collagen peptide Maillard reaction product as a product for removing fishy flavor.

[0031] The advantages of the present invention compared to the prior art are:

[0032] The invention makes full use of fishery resources and is conducive to the development of high-value utilization of aquatic products. The invention adopts oligogalactose as the polysaccharide for glycosylation reaction of collagen peptide and adopts Maillard reaction to improve the flavor of fish scale collagen peptide by simulating industrial heat sterilization conditions, effectively reduce the content of nonanal and decanal, which are fishy components, and is conducive to the development of collagen peptide Maillard flavored beverages.

[0033] The invention adopts a wet heat processing method to perform Maillard glycosylation modification on collagen peptides, thereby improving the flavor of collagen peptides. The preparation process is simple to operate, low in cost and suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The influence of glycosylation conditions on the sensory evaluation of fish scale collagen peptides.

[0035] Figure 2 Effects of glycosylation conditions on the main components of fish scale collagen peptide electronic nose.

[0036] Figure 3 Effect of glycosylation conditions on the content of volatile flavor compounds in fish scale collagen peptides.

[0037] Figure 4 Effect of glycosylation conditions on the odor activity of volatile compounds from fish scale collagen peptides. DETAILED DESCRIPTION

[0038] The present invention will be further described in detail below in conjunction with specific examples. The following examples are not intended to limit the present invention but are merely intended to illustrate the present invention.

[0039] The experimental materials of the present invention were all obtained from commercial sources, and galacto-oligosaccharide was purchased from Yunfu Xinjinshan Biotechnology Co., Ltd.

[0040] The fish scale collagen peptide used in the following examples was prepared according to the following method:

[0041] a. Tilapia scales were put into an enzymolysis tank at pH 12, bubbled and saponified for 40 minutes, and rinsed with pure water at pH 7; the addition amount of the tilapia scales in step a was 300-500 g added to 3500-5000 mL of water.

[0042] b. Raise the water temperature to 95°C and keep it warm for 1 hour for pyrolysis, stirring and bubbling during the process;

[0043] c. Cool the water temperature to 56°C, add alkaline protease for 30 minutes, then add neutral protease, continue enzymolysis for 1.5 hours, and finally add flavor protease for 1 hour; heat to 100°C and keep warm for 10 minutes to inactivate the enzyme; the enzyme addition amount in step c is 2.5-5 g alkaline protease, 1-2 g neutral protease and 0.6-1.2 g flavor protease

[0044] d. Stir the decolorization tank liquid evenly, add activated carbon and perlite to keep warm at 65°C, and stir to decolorize for 30 minutes; the amount of activated carbon added in step d is 80-120 g, and the amount of perlite added is 20-25 kg.

[0045] e. Filter through the frame until it is clear, the sample is light yellow, transparent, and free of impurities; the smell has the unique smell of collagen;

[0046] f. The filtered solution is spray-dried to obtain enzymatically hydrolyzed fish scale collagen peptides.

[0047] Example 1

[0048] Fish scale collagen peptide (1%) and galacto-oligosaccharide were dissolved in phosphate buffer (pH 8.0) at a ratio of 4:1 (m / m) and stirred in a magnetic stirrer for 20 minutes to mix them thoroughly. The mixed samples were divided into three groups, heated at 100°C for 20 minutes, and then freeze-dried for storage.

[0049] Example 2

[0050] Fish scale collagen peptide (1%) and galacto-oligosaccharide were dissolved in phosphate buffer (pH 8.0) at a ratio of 4:1 (m / m) and stirred in a magnetic stirrer for 20 minutes to mix them thoroughly. The mixed samples were divided into three groups, heated at 100°C for 40 minutes, and then freeze-dried for storage.

[0051] Example 3

[0052] Fish scale collagen peptide (1%) and galacto-oligosaccharide were dissolved in phosphate buffer (pH 8.0) at a ratio of 4:1 (m / m) and stirred in a magnetic stirrer for 20 minutes to mix them thoroughly. The mixed samples were divided into three groups, heated at 100°C for 60 minutes, and then freeze-dried for storage.

[0053] Comparative Example 1

[0054] Fish scale collagen peptide (1%) and galacto-oligosaccharide were dissolved in phosphate buffer (pH 8.0) at a ratio of 4:1 (m / m), stirred in a magnetic stirrer for 20 minutes to allow for thorough mixing, and then freeze-dried for storage.

[0055] Index detection method

[0056] (1) Sensory evaluation

[0057] 10 experienced sensory assessors were trained and selected, and they were required to be familiar with the sensory indicators such as the flavor of the samples to be tested. 0.1 g of freeze-dried sample was dissolved in 10 mL of ultrapure water, and after being kept at 37°C for 10 minutes, the sample was evaluated according to the set sensory evaluation indicators, and ultrapure water was used as the blank control of the sample to be tested.

[0058] The setting of the index is based on the characteristics of collagen peptides, mainly including the comprehensive evaluation of taste and smell. Taste characteristics include umami, bitterness, sweetness and mellowness; smell characteristics include caramel, fishy, ​​burnt and sour. The assessor needs to score the eight indicators of the sample from 0 points (no feeling) to 5 points (strong feeling). The higher the score, the stronger the smell or taste. The specific sensory ratings are as follows:

[0059] project standard 1-2 No feeling 2-4 Feeling 5 Feeling strong

[0060] (2) Electronic nose test

[0061] Dissolve 0.1 g of freeze-dried sample in 10 mL of ultrapure water, and draw 5 mL of sample into a 20 mL headspace extraction bottle. Seal and keep warm in a 60°C heating kettle for 10 minutes. Insert the needle of the electronic nose into the headspace extraction bottle. The electronic nose program is set to flush for 30 seconds, inject for 90 seconds, and the cumulative acquisition time is 120 seconds.

[0062] The electronic nose has a total of 10 sensors that can detect 10 types of flavor substances in the sample:

[0063] Array number Sensor Name Performance Description 1 W1C Sensitive to benzene and aromatic components 2 W5S Very sensitive to nitrogen oxides 3 W3C Sensitive to ammonia and aromatic ingredients 4 W6S Selective for hydrogen 5 W5C Sensitive to alkanes and aromatic components 6 W1S Sensitive to methyl 7 W1W Sensitive to sulfide 8 W2S Sensitive to alcohols, aldehydes and ketones 9 W2W Sensitive to aromatic components and organic sulfides 10 W3C Sensitive to aromatic alkanes

[0064] (3) SPME-GC-MS analysis

[0065] The flavor substances of glycosylated collagen peptides were extracted and analyzed by headspace solid-phase micro-extraction (SPME). 0.1 g of freeze-dried sample was dissolved in 10 mL of ultrapure water, and 3 mL of sample and 200 μL of internal standard solution 2,4,6-trimethylpyridine (10 ug / mL) were added to the headspace bottle and sealed. The DVB / CAR / PDMS extraction head was used to extract in a 60°C water bath for 30 min. The extraction head was inserted into the injection port and desorbed at 250°C for 10 min before injection.

[0066] GC conditions: A 30 m×0.25 mm×0.25 μm DB-WAX capillary column was used with a flow rate of 0.8 mL / min and a carrier gas of He without splitting. The initial column temperature was 40 °C, which was maintained for 3 min, then increased to 80 °C at a rate of 5 °C / min, then increased to 160 °C at a rate of 10 °C / min, maintained for 0.5 min, then increased to 175 °C at a rate of 2 °C / min, and finally increased to 230 °C at a rate of 10 °C / min, maintained for 7 min.

[0067] MS conditions were as follows: filament current was 80 μA, electron energy was 70 eV, ion source temperature was set at 250 °C, detector voltage was 1 000 V, and interface temperature was 250 °C.

[0068] Index test results

[0069] (1) Sensory evaluation

[0070] Sensory evaluation is an intuitive evaluation of samples based on the human taste and olfactory system. It can determine the overall flavor profile of the sample and evaluate the effect of glycosylation modification on the flavor of collagen peptide samples. Figure 1 As shown, compared with the comparative example, in the three groups of embodiments, the sensory scores of collagen peptides are significantly improved. In terms of smell, the fishy smell and sour taste of Examples 2 and 3 are significantly improved, and can produce caramel aroma, enriching the smell characteristics of collagen peptides, but at the same time also produces an unpleasant burnt smell. Example 1 has an improvement effect on the fishy smell, but has no obvious effect on the sour taste; in terms of taste, the three embodiments can produce the mellow feeling unique to Maillard products, and reduce the sweetness of oligosaccharides to a certain extent. Example 2 can significantly reduce the bitterness of collagen peptides and give collagen peptides a savory taste, and the effect of improving the taste of collagen peptides is the most significant.

[0071] (2) Principal component analysis of electronic nose

[0072] Principal component analysis (PCA) is a data analysis and dimensionality reduction technique for sensor data. It is mainly used to explore the main patterns and structures of multidimensional data sets and find the main variation directions in the data sets. Based on the electronic nose response value, the effect of heating conditions on the main components of oligogalactose glycosylated collagen peptides is as follows: Figure 2 As shown in the figure, in the three embodiments, the contribution rates of the first principal component (PC1) and the second principal component (PC2) are all above 98%, indicating that the two principal components can better represent the overall flavor of the sample and can better reflect the difference in odor profiles between different samples. There are obvious differences between the principal components of the embodiments and the comparative examples. There is no overlapping area between the principal component maps of the three embodiments and the comparative example, indicating that glycosylation modification can cause significant differences in the odor profile of collagen peptides. Among them, the principal component map of Example 2 is most significantly different from the principal component map of the comparative example, indicating that the main component of the glycosylated peptide heated at 100°C for 40 min is most different from the collagen peptide.

[0073] (3) SPME-GC-MS analysis

[0074] GC-MS is a detection technology that combines gas chromatography and mass spectrometry. The function of GC is separation, and the function of MS is detection. The working principle is to vaporize the sample through GC, and the vaporized compounds are separated through a capillary column and enter the ion source of MS. After bombardment by electron flow, they are ionized to obtain a chromatogram.

[0075] The unknown volatile substances are qualitatively analyzed based on the GC-MS spectrum and the linear retention index LRI in the comparison database. The volatile flavor components are quantitatively analyzed using the odor activity and internal standard method. Figure 3 , Figure 4 As shown, glycosylation modification can significantly reduce the content of aldehyde substances in fish scale collagen peptides. Aldehydes are the main volatile substances that cause the fishy smell of collagen peptides, including decanal, nonanal, heptanal, octanal, etc., which have unpleasant flavors. According to the experimental results, the concentration of nonanal in the comparative example is 8.94 ng / mL, and the concentration of decanal is 3.512 ng / mL. Since the odor threshold of nonanal and decanal is low, and the odor activity is the highest, accounting for 93.5% of the odor activity of collagen peptides, it is shown that the main flavor characteristics of collagen peptides are fishy. It can be seen from the changes in the content of volatile components in the examples that after glycosylation modification, decanal was not detected in the examples, and the nonanal content was also significantly reduced. Among them, the odor activity of nonanal in Example 2 is the lowest. Compared with the comparative example, the odor activity of nonanal is reduced by 57.38%, indicating that glycosylation modification can significantly reduce the fishy smell of collagen peptides.

[0076] In addition, benzaldehyde and ethylbenzaldehyde were detected in the examples, which can improve the flavor characteristics of collagen peptides. In Examples 1 and 3, the odor activity of benzaldehyde increased most significantly, and the flavor improvement effect was significant. In Example 2, the odor activity of ethylbenzaldehyde increased by 51.25%, and flavor substances such as thymol and 2,4-di-tert-butylphenol were generated. Therefore, glycosylation modification can not only reduce the fishy components such as nonanal and decanal contained in collagen peptides, but also generate volatile components such as benzaldehyde and thymol, thereby improving the flavor characteristics of collagen peptides.

[0077] The present invention provides a method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification. After glycosylation modification, the content of fishy smell substances in the collagen peptide is significantly reduced, the flavor of the collagen peptide is improved, and the overall acceptability of the collagen peptide is improved.

[0078] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. Application of galacto-oligosaccharides in glycosylation modification of collagen peptides.

2. The use according to claim 1, characterized in that: The application is to remove fishy smell and increase flavor.

3. A method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification, comprising the following steps: a. Put the fish scales into an enzymatic hydrolysis tank at pH 12, bubble and saponify for 40 minutes, and rinse with pure water at pH 7; b. Raise the water temperature to 95°C and keep it warm for 1 hour for pyrolysis, stirring and bubbling during the process; c. Cool the water to 56°C, add alkaline protease for 30 minutes, then add neutral protease for 1.5 hours, and finally add flavor protease for 1 hour; heat to 100°C and keep for 10 minutes to inactivate the enzyme; d. Stir the liquid in the decolorization tank evenly, add activated carbon and perlite to keep the temperature at 65℃, and stir and decolorize for 30 minutes; e. Filter through the frame until it is clear, the sample is light yellow, transparent, and free of impurities; the smell has the unique smell of collagen; f. The filtered solution is spray-dried to obtain enzymatically hydrolyzed fish scale collagen peptide; g. Dissolve fish scale collagen peptide in buffer, add galacto-oligosaccharide in a certain proportion, and stir to mix; h. The mixed sample is heated at a suitable temperature for a certain period of time; i. After the treated sample is concentrated and dried, a glycosylated collagen peptide product is obtained.

4. The method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification according to claim 3, characterized in that: The molecular weight of the fish scale collagen peptide in step g is 1500-2000 Da.

5. The method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification according to claim 3, characterized in that: The purity of the galacto-oligosaccharide in step g is 80% to 82%.

6. The method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification according to claim 3, characterized in that: The amount of fish scale collagen peptide added in step g is 1% to 3%, and the amount of galacto-oligosaccharide added is 4% to 12%.

7. The method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification according to claim 3, characterized in that: The buffer in step g is a 50-100 mM phosphate buffer solution with a pH of 8.0-8.

5.

8. The method for removing the fishy smell of fish scale collagen peptide based on glycosylation modification according to claim 3, characterized in that: The heating conditions in step h simulate the low glycosylation degree heating conditions and industrial thermal sterilization conditions, with a specific heating temperature of 100-105° C. and a heating time of 30-40 min.

9. A glycosylated fish scale collagen peptide product prepared by the method according to any one of claims 3 to 8.

10. Application of the glycosylated fish scale collagen peptide product according to claim 9 in food and medicine.

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