A method for removing fishy smell from pigeon meat protein peptide

Abstract

The present invention is a method for removing the fishy smell of pigeon protein peptides. The method comprises the following steps: rinsing the pigeon minced meat with an aqueous solution containing NaCl and alcohol, centrifuging to obtain a precipitate and washing the precipitate; treating the washed precipitate with a defatting treatment solution; adjusting the pH of the treated defatting mixed solution to the isoelectric point of the pigeon protein with NaOH to obtain a defatted pigeon protein isolate; adding water to the obtained pigeon protein isolate, adding a Maillard reactant and a protease, performing enzyme deactivation treatment after a period of enzymolysis, and finally clarifying and removing the fishy smell and coloring the enzymolysis solution with chitosan. Compared with conventional techniques, the present invention significantly improves the fishy smell of the enzymolysis solution, and because the addition of the Maillard reactant gives the enzymolysis solution a special aroma, the flavor of the enzymolysis solution is improved, and the effect of enhancing the flavor and removing the bitterness is achieved; while ensuring nutrition, a better deodorizing and decolorizing effect is achieved. The method provides a technical reference for the processing and utilization of pigeon active peptides, and also provides a new idea for the deodorization of other protein peptides.

Description

Technical Field

[0001] The invention belongs to the technical field of protein peptide deodorization, and particularly relates to a method for deodorizing pigeon meat protein peptide. Background Art

[0002] As people's living standards continue to improve, the quality and convenience of meat are becoming more and more demanding. People hope that meat products can not only satisfy the delicious meat but also play a role in diet and health care, and pigeons can meet this requirement. Pigeon meat is tender, delicious, and has high nutritional value. It is not only a precious delicacy, but also a high-end tonic. Pigeon meat is a high-protein, low-fat food. Its protein content can reach 20-24%, ranking first among poultry. At the same time, the essential amino acid composition of pigeon meat is complete, and it contains rich minerals and vitamins that help the human body digest and utilize. "One pigeon is better than nine chickens." Practice has proved that meat pigeons are a traditional treasure that combines nourishment and diet for pregnant women, postoperative patients, chronically ill and weak people, and the elderly.

[0003] The research and development of pigeon meat mainly focuses on flavored meat products, and the processing and development of high value-added products are less. Among them, pigeon essence is mostly prepared from pigeon meat, which to some extent causes a waste of resources for the active functions of pigeon meat. At present, active peptides and protein hydrolysates in my country are mainly concentrated in soy protein, milk protein and fish protein, and there are fewer studies on other proteins, and the active functions of pigeon meat protein are even fewer. Deep processing of pigeon meat protein by enzymatic hydrolysis can obtain more easily digestible and absorbable polypeptides and amino acids, which can greatly improve its nutritional value and commercial value. The polypeptides in the enzymatic hydrolyzate are more biologically active than amino acids. Therefore, in order to prepare health care functional products, the main components of enzymatic hydrolysis should be peptide substances, but the current pigeon meat enzymatic peptides still have problems such as fishy smell and unclear color, which hinder the application and development of pigeon meat enzymatic peptides.

[0004] At present, there are three main methods for deodorization: chemical deodorization, physical deodorization, and biological fermentation deodorization. Physical deodorization is mainly activated carbon adsorption, which has a good deodorization effect, but the protein loss rate is relatively high; chemical deodorization has a certain deodorization effect, but at the same time introduces some chemical reagents, which is easy to cause reagent residues and introduce impurities into the product; biological fermentation deodorization methods such as yeast are less efficient, and the fermentation process is difficult to control. The addition of yeast will also introduce some odors. Therefore, it is necessary to improve and innovate the deodorization method, and to deodorize the pigeon meat enzymatic hydrolyzate while ensuring that the nutritional loss of pigeon meat protein is extremely low, so as to provide a technical reference for the deep processing of pigeon meat. Summary of the invention

[0005] In order to solve the problem of the fishy smell of the current pigeon meat protein peptides, the present invention provides a method for removing the fishy smell of the pigeon meat protein peptides.

[0006] In order to achieve the above object, the present invention provides a method for removing the fishy smell of pigeon protein peptides, comprising the following steps:

[0007] (1) Rinsing: Take pigeon meat and mince it to obtain minced pigeon meat; rinse the minced pigeon meat with an aqueous solution containing NaCl and alcohol, centrifuge to obtain a precipitate and wash it, and preliminarily remove hemoglobin and fishy substances in the minced pigeon meat;

[0008] (2) defatting: adding the washed precipitate obtained in step (1) to a defatting solution and stirring to preliminarily remove the phospholipids in the pigeon meat;

[0009] (3) separating pigeon protein: taking the defatted mixed solution treated in step (2), adjusting the pH to the isoelectric point of pigeon protein with NaOH, mixing the adjusted mixed solution, centrifuging and filtering, taking the filtrate, adjusting the pH again, centrifuging to precipitate the pigeon protein, filtering and washing to obtain defatted pigeon protein isolate;

[0010] (4) enzymolysis: taking the pigeon protein isolate obtained in step (3), adding water, and adding Maillard reactants and protease, enzymolysis for a period of time, after which the enzyme is inactivated, and then centrifuging to obtain a pigeon protein hydrolysate;

[0011] (5) Clarification: chitosan is added to the pigeon meat protein hydrolysate, mixed evenly and allowed to stand, centrifuged to obtain the deodorized protein hydrolysate, and then freeze-dried to obtain the deodorized pigeon meat protein hydrolysate peptides.

[0012] As a preferred embodiment of the present invention, in step (1), the mass fraction of NaCl in the aqueous solution is 0.3-0.7%, the mass fraction of alcohol is 0.8-1.2%, the material-liquid ratio of the solution to the pigeon minced meat is 1:2-1:4 g / mL, the rinsing temperature range is 4-10°C, the rinsing time is 30-60 min, and the precipitate is washed with cold water at 4-10°C for 2-3 times.

[0013] As a preferred embodiment of the present invention, in step (2), the degreasing treatment liquid includes 0.08-0.1% CaCl2, 0.05-0.08% malic acid, 0.02-0.05% sodium isoascorbate and 0.05-0.10% green tea extract by mass fraction; the solid-liquid ratio of the precipitate to the degreasing treatment liquid is 1:4-1:8, the stirring temperature is 4-10°C, and the stirring time is 30-60min.

[0014] As a preferred embodiment of the present invention, in step (3), the pH of the defatted mixed solution is adjusted to 11-11.5 with NaOH, mixed and stirred, centrifuged, and the filtrate is adjusted to pH 5-5.5 with citric acid, and the precipitate is centrifuged and washed to obtain pigeon protein isolate.

[0015] As a preferred embodiment of the present invention, in step (4), the material-liquid ratio of pigeon protein isolate to water is 1:2-1:4; the Maillard reactants include xylose and cysteine, and the mass percentage of xylose added to the mixture of pigeon protein isolate and water is 0.5-1%, and the mass percentage of cysteine ​​is 0.5-1%.

[0016] As a preferred embodiment of the present invention, during the enzymatic hydrolysis process of step (4), alkaline protease is added to the mixture after adding water to the pigeon protein isolate, and the mass percentage of the alkaline protease in the mixture is 1-2%; the enzymatic hydrolysis is carried out at 50-55° C. and pH 8-9 for 4-5 hours, and then the pH of the mixture is adjusted to 6-7, and then flavor protease is added, and the mass percentage of the flavor protease in the mixture is 2-3%, and the enzymatic hydrolysis is continued for 2-3 hours.

[0017] As a preferred embodiment of the present invention, in step (5), the mass percentage of chitosan added to the pigeon meat protein hydrolysate is 0.02-0.05%, the temperature during mixing is 32-37° C., and the standing time is 30-60 min.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The rinsing technology of the present invention adopts salt and alcohol low-temperature rinsing, wherein salt is used to increase the ionic strength in pigeon meat homogenate, which is beneficial to the leaching of impurities and some fishy substances, and alcohol is used to enhance the dissolution of alcohol-soluble fishy substances in low-temperature homogenate, thereby removing impurities such as alcohol-soluble fishy substances and hemoglobin in pigeon meat paste, thereby achieving efficient initial fishy removal.

[0020] The invention designs a novel degreasing treatment liquid, which has a mild degreasing process, a high protein recovery rate and is easy to operate. CaCl2 and malic acid in the degreasing treatment liquid can promote the removal of phospholipids in pigeon minced meat, while sodium isoascorbate and green tea extract can prevent oxidation of defatted pigeon minced meat, and the introduction of antioxidant deodorization technology can effectively remove the fishy smell of pigeon minced meat, and prolong the storage time, which is beneficial to subsequent processing and production.

[0021] The invention adopts a deodorizing method combining composite enzymolysis and Maillard reaction. The enzymolysis reaction releases flavor amino acids and reduces the bitterness of the enzymolysis solution through composite enzymolysis. The Maillard reaction gives the enzymolysis solution a special aroma, improves the flavor of the enzymolysis solution, and plays the role of enhancing fragrance and removing bitterness.

[0022] The present invention adopts chitosan flocculation technology, and chitosan can flocculate and precipitate small particles of insoluble impurities in the enzymatic hydrolysate that cannot be resolved by centrifugation, so as to obtain a clarified pigeon meat enzymatic hydrolysate. The flocculated enzymatic hydrolysate is clearer, and chitosan itself has excellent biocompatibility and physiological functions such as enhancing immunity, thus giving the pigeon meat enzymatic hydrolysate certain functionality.

[0023] The invention solves the problem of the fishy smell of pigeon meat enzymatic peptides and achieves flavor enhancement, while the nutritional loss rate is low. It can provide a technical reference for the processing and utilization of pigeon meat active peptides and also provide a new idea for the removal of fishy smell from other protein peptides. DETAILED DESCRIPTION

[0024] The present invention is further described and illustrated below in conjunction with specific embodiments. The embodiments are merely exemplary of the present disclosure and do not define the scope of limitation. The technical features of each embodiment of the present invention may be combined accordingly without conflicting with each other.

[0025] Embodiment 1:

[0026] After washing the pigeon, take the breast meat and grind it with a meat grinder to get the minced pigeon meat. Mix the minced pigeon meat with an aqueous solution containing 0.5% NaCl and 1% alcohol at a solid-liquid ratio of 1:2, rinse at 4°C for 30 minutes, and centrifuge to obtain a precipitate to preliminarily remove the hemoglobin and fishy substances in the minced pigeon meat. Take the precipitate and add the defatting treatment liquid at a solid-liquid ratio of 1:5. The defatting treatment liquid contains 0.08% CaCl2, 0.05% malic acid, 0.02% sodium isoascorbate, and 0.1% green tea extract by mass fraction, and stir at 4°C for 30 minutes to preliminarily remove the phospholipids in the pigeon meat. Then adjust the pH of the homogenate to 11-11.5 with NaOH, mix and stir at 4°C, centrifuge to obtain the clear liquid, and then adjust the pH of the clear liquid to 5-5.5, stir and centrifuge to obtain the defatted pigeon meat protein isolate. The precipitate was added with water at a material-liquid ratio of 1:3, and 1% xylose and 1% cysteine ​​were added. The mixture was heated to 50°C, the pH was adjusted to 8, 1% alkaline protease was added, and the enzymatic hydrolysis conditions were changed after stirring for 4 hours. The pH of the mixture was adjusted to 6, 2% flavor protease was added, and the enzymatic hydrolysis was performed for 3 hours. After the end, the enzyme was inactivated at 121°C for 30 minutes, and the flavor of the enzymatic hydrolyzate was modified by Maillard reaction. The inactivated enzymatic hydrolyzate was centrifuged at 8000r / min for 15 minutes to obtain pigeon meat protein hydrolyzate. 0.02% chitosan was added to the pigeon meat protein hydrolyzate, mixed evenly at 35°C, allowed to stand for 0.5 hours, and centrifuged to obtain a deodorized enzymatic hydrolyzate, which was then freeze-dried to obtain deodorized pigeon meat protein hydrolyzate peptides.

[0027] Embodiment 2:

[0028] After washing the pigeon, take the breast meat and grind it with a meat grinder to get the minced pigeon meat. Mix the minced pigeon meat with an aqueous solution containing 0.5% NaCl and 1% alcohol at a solid-liquid ratio of 1:2, rinse at 4°C for 30 minutes, and centrifuge to obtain a precipitate to preliminarily remove the hemoglobin and fishy substances in the minced pigeon meat. Take the precipitate and add the defatting treatment liquid at a solid-liquid ratio of 1:5. The defatting treatment liquid contains 0.1% CaCl2, 0.05% malic acid, 0.02% sodium isoascorbate, and 0.1% green tea extract by mass fraction, and stir at 4°C for 30 minutes to preliminarily remove the phospholipids in the pigeon meat. Then adjust the pH of the homogenate to 11-11.5 with NaOH, mix and stir at 4°C, centrifuge to obtain the clear liquid, and then adjust the pH of the clear liquid to 5-5.5. After stirring, centrifuge to obtain the defatted pigeon meat protein isolate. The precipitate was added with water at a material-liquid ratio of 1:3, and 1% xylose and 1% cysteine ​​were added. The mixture was heated to 50°C, the pH was adjusted to 9, 1% alkaline protease was added, and the enzymatic hydrolysis conditions were changed after stirring for 4 hours. The pH of the mixture was adjusted to 6, 2% flavor protease was added, and the enzymatic hydrolysis was performed for 3 hours. After the end, the enzyme was inactivated at 121°C for 30 minutes, and the flavor of the enzymatic hydrolyzate was modified by Maillard reaction. The inactivated enzymatic hydrolyzate was centrifuged at 8000r / min for 15 minutes to obtain pigeon meat protein hydrolyzate. 0.02% chitosan was added to the pigeon meat protein hydrolyzate, mixed evenly at 35°C, allowed to stand for 0.5 hours, and centrifuged to obtain a deodorized enzymatic hydrolyzate, which was then freeze-dried to obtain deodorized pigeon meat protein hydrolyzate peptides.

[0029] Embodiment 3:

[0030] After washing the pigeon, take the breast meat and grind it with a meat grinder to get the minced pigeon meat. Mix the minced pigeon meat with an aqueous solution containing 0.5% NaCl and 1% alcohol at a solid-liquid ratio of 1:2, rinse at 10°C for 30 minutes, and centrifuge to obtain a precipitate to preliminarily remove the hemoglobin and fishy substances in the minced pigeon meat. Take the precipitate and add the defatting treatment liquid at a solid-liquid ratio of 1:5. The defatting treatment liquid contains 0.1% CaCl2, 0.08% malic acid, 0.02% sodium isoascorbate, and 0.1% green tea extract by mass fraction, and stir at 4°C for 30 minutes to preliminarily remove the phospholipids in the pigeon meat. Then adjust the pH of the homogenate to 11-11.5 with NaOH, mix and stir at 4°C, centrifuge to obtain the clear liquid, and then adjust the pH of the clear liquid to 5-5.5. After stirring, centrifuge to obtain the defatted pigeon meat protein isolate. The precipitate was added with water at a material-liquid ratio of 1:3, and 1% xylose and 1% cysteine ​​were added. The mixture was heated to 55°C, the pH was adjusted to 9, 2% alkaline protease was added, and the enzymatic hydrolysis conditions were changed after stirring for 4 hours. The pH of the mixture was adjusted to 7, 3% flavor protease was added, and the enzymatic hydrolysis was performed for 3 hours. After the end, the enzyme was inactivated at 121°C for 30 minutes, and the flavor of the enzymatic hydrolyzate was modified by Maillard reaction. The inactivated enzymatic hydrolyzate was centrifuged at 8000r / min for 15 minutes to obtain pigeon meat protein hydrolyzate. 0.02% chitosan was added to the pigeon meat protein hydrolyzate, mixed evenly at 35°C, allowed to stand for 0.5 hours, and centrifuged to obtain a deodorized enzymatic hydrolyzate, which was then freeze-dried to obtain deodorized pigeon meat protein hydrolyzate peptides.

[0031] In order to verify the effectiveness of this deodorization method, this deodorization method was compared with the traditional activated carbon deodorization method, and the test was as follows:

[0032] Untreated enzymatic hydrolysate, the deodorized enzymatic hydrolysate and activated carbon treated enzymatic hydrolysate were prepared, and their fishy smell, protein loss rate and other results were compared.

[0033] The sensory evaluation staff consisted of 10 people, 5 men and 5 women, aged 23-30. The maximum score for the fishy smell was 10 points, and the higher the score, the less fishy the smell.

[0034] The comparison results are as follows:

[0035] sample Sensory evaluation of fishy smell removal Protein loss rate Clarity Untreated enzymatic solution 3.25 —— Poor Example 1 Enzyme hydrolysate 8.85 7.285％ clarify Example 2 Enzymolysis Solution 9.15 5.622％ clarify Example 3 Enzymolysis Solution 9.1 5.719％ clarify Activated carbon treatment of enzymatic hydrolysate 8.65 15.341％ Clearer

[0036] According to the table, the deodorizing effect of the present deodorizing method is relatively good. The three embodiments can achieve the deodorizing effect of activated carbon. At the same time, the protein loss rate of the present deodorizing method is significantly lower than that of the deodorizing method using activated carbon, which can better ensure the effective utilization of the nutritional value of pigeon meat. In terms of clarity, the deodorizing enzymatic hydrolysate is uniformly clear, while the deodorizing method using traditional activated carbon can also obtain a relatively clear liquid, but the removal of activated carbon is also a problem, which will lead to the problem of residual activated carbon and darkening of the color of the enzymatic hydrolysate.

[0037] The protein loss rate of the products obtained in the above embodiments is low. Compared with conventional technologies, the fishy smell of the enzymatic hydrolysate is significantly improved. Moreover, because the Maillard reactant is added to modify the flavor, the enzymatic hydrolysate has a strong meaty aroma, achieving a better effect of removing fishy smell and enhancing flavor.

[0038] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. For ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A method for removing the fishy smell of pigeon protein peptides, characterized in that: The steps include: (1) Rinsing: Take pigeon meat and mince it to obtain minced pigeon meat; rinse the minced pigeon meat with an aqueous solution containing NaCl and alcohol, centrifuge to obtain a precipitate and wash it, and preliminarily remove hemoglobin and fishy substances in the minced pigeon meat; (2) defatting: adding the washed precipitate obtained in step (1) to a defatting solution and stirring to preliminarily remove the phospholipids in the pigeon meat; In step (2), the degreasing treatment liquid includes 0.08-0.1% by mass of CaCl2, 0.05-0.08% by mass of malic acid, 0.02-0.05% by mass of sodium isoascorbate and 0.05-0.10% by mass of green tea extract; (3) separating pigeon protein: taking the defatted mixed solution treated in step (2), adjusting the pH to the isoelectric point of pigeon protein with NaOH, mixing the adjusted mixed solution, centrifuging and filtering, taking the filtrate, adjusting the pH again, centrifuging to precipitate the pigeon protein, filtering and washing to obtain defatted pigeon protein isolate; (4) enzymolysis: taking the pigeon protein isolate obtained in step (3), adding water, and adding Maillard reactants and protease, enzymolysis for a period of time, after which the enzyme is inactivated, and then centrifuging to obtain a pigeon protease hydrolyzate; In step (4), the material-liquid ratio of pigeon protein isolate to water is 1:2-1:4; the Maillard reactants include xylose and cysteine, and the mass percentage of xylose added to the mixture of pigeon protein isolate and water is 0.5-1%, and the mass percentage of cysteine ​​is 0.5-1%; During the enzymatic hydrolysis process of step (4), alkaline protease is added to the mixture after adding water to the pigeon protein isolate, and the mass percentage of alkaline protease in the mixture is 1-2%; enzymatic hydrolysis is carried out at 50-55° C. and pH 8-9 for 4-5 hours, and then the pH of the mixture is adjusted to 6-7, and then flavor protease is added, and the mass percentage of flavor protease in the mixture is 2-3%, and the enzymatic hydrolysis is continued for 2-3 hours; (5) Clarification: chitosan is added to the pigeon meat protein hydrolysate, mixed evenly and allowed to stand, centrifuged to obtain the deodorized protein hydrolysate, and then freeze-dried to obtain the deodorized pigeon meat protein hydrolysate peptides.

2. A method for removing fishy smell from pigeon protein peptide according to claim 1, characterized in that: In step (1), the mass fraction of NaCl in the aqueous solution is 0.3-0.7%, the mass fraction of alcohol is 0.8-1.2%, the material-liquid ratio of the solution to the pigeon minced meat is 1:2-1:4 g / mL, the rinsing temperature range is 4-10°C, the rinsing time is 30-60 minutes, and the precipitate is washed with cold water at 4-10°C for 2-3 times.

3. A method for removing fishy smell from pigeon protein peptide according to claim 1, characterized in that: In step (2), the material-liquid ratio of the precipitate to the degreasing treatment liquid is 1:4-1:8, the stirring temperature is 4-10°C, and the stirring time is 30-60 minutes.

4. A method for removing fishy smell from pigeon protein peptide according to claim 1, characterized in that: In step (3), the pH of the defatted mixed solution is adjusted to 11-11.5 with NaOH, the mixture is mixed and stirred, and the filtrate is centrifuged and the pH is adjusted to 5-5.5 with citric acid, and the precipitate is centrifuged and washed to obtain pigeon protein isolate.

5. A method for removing fishy smell from pigeon protein peptide according to claim 1, characterized in that: In step (5), the mass percentage of chitosan added to the pigeon meat protein hydrolysate is 0.02-0.05%, the temperature during mixing is 32-37° C., and the standing time is 30-60 min.