Pretreatment shrimp shelling promoting method

Abstract

The invention relates to the technical field of shrimp shelling, and particularly discloses a pretreatment shrimp shelling promoting method, which comprises the following steps of: 1, preparing slurry ice with the salt content of 2.6 to 5 percent; the volume ratio of ice to water in the ice slurry is 7: 3. And 2, completely putting the shrimp bodies with the shells into ice slurry, and refrigerating for 1.5-4 hours. And 3, taking out the shrimp bodies. According to the method disclosed by the invention, after the prawns are pretreated, the work and time of shelling can be effectively reduced, and meanwhile, the high quality of the prawns can be kept. According to the method, the shelling efficiency is improved, meanwhile, the high shrimp meat quality can be kept, the price is economical, operation is easy, and therefore the influence of pretreatment on the shrimp meat quality can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of shrimp shelling, in particular to a pretreatment method for promoting shrimp shelling. Background Art

[0002] Shrimp is a food with high nutritional value. People often need to spit out the shells when eating shrimp. In order to simplify the process of eating, some manufacturers often shell the shrimp and turn it directly into shrimp meat.

[0003] Over the years, in order to improve the peelability of shrimp, the integrity and quality of shrimp meat, and realize continuous industrialized and mechanized production in the shrimp processing industry, people have tried to find various shelling pretreatment technologies, including low-temperature freezing treatment, heat treatment, pressure, ultrasound, microwave and other stimulations to promote the loosening of the connection between the shrimp shell and the meat, making it easier to shell.

[0004] Heat treatment requires the shrimp to be cooked, which affects the flavor and texture of the shrimp and reduces the value of the product. Low-temperature treatment uses ice or freezing to treat fresh shrimp, which is economical, simple and convenient, but it is easy to produce large ice crystals, which can easily damage the cell tissue of the shrimp, cause protein denaturation, and harden the meat. Slurry ice is a new low-temperature treatment method that can effectively reduce the damage of ice crystals to the shrimp tissue and ensure product quality. However, if the salt water concentration is too high, it will cause the sample to freeze quickly. The expansion pressure generated by the freezing of the muscle makes it more difficult to separate the shell from the meat, resulting in reduced shelling efficiency and serious loss of shrimp body. In addition, as the soaking time increases, salt can easily penetrate into the shrimp body, affecting the quality of the product.

[0005] Ultra-high pressure technology uses fluid as a medium and maintains a pressure of 200-100MPa for a certain period of time to shed shrimps. High pressure can easily destroy the secondary, tertiary and quaternary structures of the protein, and can easily cause different degrees of deterioration in physical and chemical indicators such as the sensory properties of the shrimp and the biochemical properties of the protein. At the same time, ultra-high pressure equipment is expensive and has a small volume, making it difficult to meet production needs.

[0006] Enzymatic hydrolysis promotes shrimp shelling by using proteases to break down proteins in the shrimp skin and shell, increasing the gap between the shell and the meat, thus posing a risk of microbial contamination. In addition, during the enzymatic maturation process, the enzyme liquid that penetrates into the meat may cause drip loss and softening of the meat during storage. Summary of the invention

[0007] The object of the present invention is to provide a method for pre-treating shrimps to promote shelling, so as to solve at least one technical problem existing in the above-mentioned prior art.

[0008] To achieve the above object, the present invention provides the following technical solution: a pretreatment method for promoting shrimp molting, the first step of which is to prepare fluidized ice with a salt content of 2.6%-5%; the volume ratio of ice to water in the fluidized ice is 7:3.

[0009] The second step is to completely place the shrimp bodies in the shells in liquid ice and refrigerate for 1.5-4 hours.

[0010] The third step is to take out the shrimp body.

[0011] Preferably, in the second step, the refrigeration time is 1.5 hours, and the salt content of the slurry ice is 3%. Preferably, in the second step, the refrigeration time is 1.5 hours, and the salt content of the slurry ice is 4%.

[0012] Preferably, in the second step, the refrigeration time is 1.5 hours and the salt content of the liquid ice is 5%.

[0013] Preferably, in the second step, the refrigeration time is 4 hours and the salt content of the liquid ice is 3%.

[0014] Preferably, in the second step, the refrigeration time is 4 hours and the salt content of the liquid ice is 4%.

[0015] Preferably, in the second step, the refrigeration time is 4 hours and the salt content of the liquid ice is 5%.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention can effectively reduce the damage of ice crystals to shrimp tissue by using fluidized ice, thereby ensuring product quality and taste. Selecting fluidized ice with a salt content of 2.6%-5% can prevent shrimp from freezing quickly, prevent the shell and meat from being difficult to separate due to the freezing and expansion of shrimp meat, improve shelling efficiency, and reduce shrimp meat loss. In addition, selecting the above time range can avoid the soaking time, which can reduce the situation of salt infiltration into shrimp meat caused by too long soaking time, and can also ensure that the shrimp can get a suitable processing time, so that the efficiency and shrimp meat quality can be balanced.

[0018] The present invention can improve the shelling efficiency while retaining a high shrimp quality, and has economical price and simple operation, thereby reducing the influence of pretreatment on the shrimp quality. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Implementation method 1:

[0021] The invention provides a technical solution: a pretreatment method for promoting shrimp molting, wherein the first step is to prepare fluidized ice with a salt content of 2.6% to 5%; the volume ratio of ice to water in the fluidized ice is 7:3.

[0022] The second step is to completely place the shrimp bodies in the shells in liquid ice and refrigerate for 1.5-4 hours.

[0023] The third step is to take out the shrimp body.

[0024] Slurry ice is a new type of low-temperature processing method. The use of slurry ice can effectively reduce the damage of ice crystals to shrimp tissue, thereby ensuring product quality and taste. Selecting slurry ice with a salt content of 2.6%-5% can prevent shrimp from freezing quickly, prevent the shell and meat from being difficult to separate due to the freezing and expansion of shrimp meat, improve shelling efficiency, and reduce shrimp meat loss. In addition, selecting the above time range can avoid soaking time, which can reduce the situation of salt infiltration into shrimp meat caused by soaking time too long, and can also ensure that the shrimp can get a suitable processing time, so that efficiency and shrimp meat quality can be balanced.

[0025] On the basis of this embodiment, it is further selected that in the second step, the refrigeration time is 1.5 hours.

[0026] On the basis of the above, the salt content of liquid ice is selected to be 3%.

[0027] On the basis of the above, the salt content of liquid ice is selected to be 4%.

[0028] On the basis of the above, the salt content of liquid ice is selected to be 5%.

[0029] The following indicators were used to evaluate the effect of the present invention:

[0030] 1. The difficulty of shelling is measured by manual shelling time and the tensile force for separating the shrimp shell and the meat is evaluated by a texture analyzer.

[0031] 2. The integrity of the shrimp is determined by whether the shrimp tail is broken.

[0032] 3. Evaluation of shrimp quality from moisture, pH value and meat hardness

[0033] The comparative example is that the shrimp bodies without pretreatment are directly shelled.

[0034] The white shrimps obtained from the different selection conditions in the above embodiments and comparative example 1 were shelled and evaluated for quality. 100 samples were taken from each group for manual peeling, and the average time required for shelling and the tail breakage rate were recorded. Determination of the tensile force for separating the shell and meat of shrimps Take the first three sections of the shrimp abdomen, cut off the shrimp whiskers, and weigh them. During the shelling process, insert the upper needle between the shrimp shell and the shrimp meat, and the lower needle into the shrimp meat. The shelling process of the research object was analyzed, and the parameters were set as follows: tensile test mode, test speed 2.5mm / s, distance 60mm, trigger force 5.0g. The determination of the moisture content and pH value of shrimp meat refers to the national standards GB5009.237-2016 and GB5009.3-2016. Hardness Take the muscles of the second abdominal segment of the shelled white shrimp and compress them twice, and measure them separately using the TPA mode of the texture analyzer. The test conditions are: flat-bottomed probe P / 100, pre-test rate 3.00mm / s, test rate 1.00mm / s, post-test rate 1.00mm / s, compression deformation rate 40%, dwelling interval 5s, and load probe 5g.

[0035] Table 1 Shelling and quality evaluation results of whiteleg shrimp obtained by different pre-treatment methods:

[0036] Salt content Shelling time / s Shelling work / (mJ / g) Tail breaking rate Sensory evaluation (full score 20) pH Meat hardness / N 3％ 40.1 2.1 0.18 18.5 7.33 16.48 4％ 38.1 1.6 0.15 19 7.27 14.59 5％ 37.9 1.5 0.12 18.8 7.22 16.53 Comparative Example 48.0 4.18 0.6 20 7.06 13.65

[0037] Table 1

[0038] Implementation method 2:

[0039] The invention provides a technical solution: a pretreatment method for promoting shrimp molting, wherein the first step is to prepare fluidized ice with a salt content of 2.6% to 5%; the volume ratio of ice to water in the fluidized ice is 7:3.

[0040] The second step is to completely place the shrimp bodies in the shells in liquid ice and refrigerate for 1.5-4 hours.

[0041] The third step is to take out the shrimp body.

[0042] On the basis of this embodiment, it is further selected that in the second step, the refrigeration time is 4 hours.

[0043] On the basis of the above, the salt content of liquid ice is selected to be 3%.

[0044] On the basis of the above, the salt content of liquid ice is selected to be 4%.

[0045] On the basis of the above, the salt content of liquid ice is selected to be 5%.

[0046] The following indicators were used to evaluate the effect of the present invention:

[0047] 4. The difficulty of shelling is measured by manual shelling time and evaluated by the tensile force of separating the shrimp shell and the meat measured by texture analyzer.

[0048] 5. The integrity of the shrimp is determined by whether the shrimp tail is broken.

[0049] 6. The quality of shrimp is evaluated based on moisture, pH value and meat hardness.

[0050] The comparative example is that the shrimp bodies without pretreatment are directly shelled.

[0051] The white shrimps obtained from the different selection conditions in the above embodiments and comparative example 1 were shelled and evaluated for quality. 100 samples were taken from each group for manual peeling, and the average time required for shelling and the tail breakage rate were recorded. Determination of the tensile force for separating the shell and meat of shrimps Take the first three sections of the shrimp abdomen, cut off the shrimp whiskers, and weigh them. During the shelling process, insert the upper needle between the shrimp shell and the shrimp meat, and the lower needle into the shrimp meat. The shelling process of the research object was analyzed, and the parameters were set as follows: tensile test mode, test speed 2.5mm / s, distance 60mm, trigger force 5.0g. The determination of the moisture content and pH value of shrimp meat refers to the national standards GB5009.237-2016 and GB5009.3-2016. Hardness Take the muscles of the second abdominal segment of the shelled white shrimp and compress them twice, and measure them separately using the TPA mode of the texture analyzer. The test conditions are: flat-bottomed probe P / 100, pre-test rate 3.00mm / s, test rate 1.00mm / s, post-test rate 1.00mm / s, compression deformation rate 40%, dwelling interval 5s, and load probe 5g.

[0052] Table 2 Shelling and quality evaluation results of white shrimp obtained by different pre-treatment methods:

[0053]

[0054]

[0055] Table 2

[0056] By comparing the numerical values ​​between the schemes in the first and second embodiments and the comparative examples, it is not difficult to find that after the shrimp body is pretreated by the method provided by the present invention, the shelling time and shelling work of the shrimp body are significantly reduced, that is, the shelling efficiency is greatly improved. In addition, the tail breakage rate is also greatly reduced, so that the integrity of the shrimp meat after the shrimp tail is shelled can be maintained to a greater extent. At the same time, a higher quality is retained in terms of sensory evaluation, pH value and meat hardness.

[0057] Therefore, it can be concluded that the work and time of shelling can be effectively reduced after pretreatment by the present invention, and the quality of shrimp can also be retained at a high level. The present invention can improve the efficiency of shelling while retaining a high quality of shrimp, and is economical in price and simple in operation, thereby reducing the impact of pretreatment on the quality of shrimp.

[0058] The standard parts used in this embodiment can be purchased directly from the market, and the non-standard structural components recorded in the specification can also be directly processed according to existing technical common sense. At the same time, the connection method of each component adopts the mature conventional means in the prior art, and the machinery, parts and equipment all adopt the conventional models in the prior art, so no specific description will be given here.

[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for pre-treating shrimp to promote shelling, characterized in that: The first step is to prepare slurry ice with a salt content of 2.6% to 5%; the volume ratio of ice to water in the slurry ice is 7:3; Step 2: Place the shrimp in shells completely in liquid ice and refrigerate for 1.5-4 hours; The third step is to take out the shrimp body.

2. The method for promoting shrimp molting by pretreatment according to claim 1, characterized in that: In the second step, the refrigeration time is 1.5 hours.

3. The method for promoting shrimp molting by pretreatment according to claim 1, characterized in that: In the second step, the refrigeration time is 4 hours.

4. The method for promoting shrimp molting by pretreatment according to claim 1 or 2, characterized in that: The salt content of the fluidized ice is 3%.

5. The method for promoting shrimp molting by pretreatment according to claim 1 or 2, characterized in that: The salt content of the fluid ice is 4%.

6. The method for promoting shrimp molting by pretreatment according to claim 1 or 2, characterized in that: The salt content of the fluidized ice is 5%.

7. The method for promoting shrimp molting by pretreatment according to claim 1 or 3, characterized in that: The salt content of the fluid ice is 3%.

8. The method for promoting shrimp molting by pretreatment according to claim 1 or 3, characterized in that: The salt content of the fluidized ice is 4%.

9. The method for promoting shrimp molting by pretreatment according to claim 1 or 3, characterized in that: The salt content of the fluidized ice is 4%.

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