Shell opening solution for Fujian oysters and application

Abstract

The invention belongs to the technical field of aquatic product processing, and discloses a shell opening solution for Fujian oysters and application. The invention provides a shell opening solution for Fujian oysters. The shell opening solution comprises a magnesium chloride solution with the concentration of 0.5 mol / L-0. 6 mol / L and / or a glucose solution with the concentration of 0.5 mol / L-0. 6 mol / L. The shell opening solution is used for conducting living body paralysis on the Fujian oysters and then conducting shell opening, the food safety risk of manual oyster opening and meat taking is reduced, the Fujian oyster shell opening and meat taking efficiency is improved, manual operation is reduced, and the oyster opening rate of a biological shell opening method can reach 90% or above. The oyster meat processed by the shell opening solution is higher in yield and free of salt ion residues, various indexes of aquatic product processing are met, and oyster juice prepared from the oyster meat is better in quality, flavor and preservative capacity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aquatic product processing, in particular to a shell opening solution for Crassostrea angulata and application thereof. BACKGROUND

[0002] Oyster has high nutritional value and is widely cultivated in the world. Crassostrea angulata, also known as Portuguese oyster, is rich in minerals such as zinc, selenium and iron, as well as vitamin B12 and taurine, and has the characteristics of thin shell and fast growth, and is an important oyster breeding species in the south of China. It is also a suitable species for oyster juice preparation, and the oyster juice prepared from Crassostrea angulata has a unique seafood flavor.

[0003] At present, magnesium salt seawater solution is often used to paralyze live shellfish, and the survival rate after recovery is concerned after live sampling, which effectively ensures the protection and reservation of key samples or germplasm resources. For example, the patent document CN101849520A discloses a method for opening the shell of a live bivalve, which uses magnesium salt seawater solution to soak the bivalve for scientific research and production practice, and the survival rate can reach more than 95%. The patent document CN110720415A discloses a method for opening the shell of a live bivalve, which uses a shell opening solution including seawater, fresh water and magnesium chloride to soak the pearl oyster, and the survival rate of the pearl oyster after recovery is high. The patent document CN115786462A discloses a method for preparing a sample for long oyster live genome DNA analysis, which uses magnesium ions for anesthesia to slightly open the shell, and uses a disposable sterile syringe needle to extract tissue fluid from the adductor muscle, centrifuges the extracted tissue fluid, and then extracts DNA, which can meet the research needs of long oyster live DNA analysis. However, the existing shell opening methods are difficult to balance safety and the quality and flavor of oyster meat after shell opening. SUMMARY

[0004] The present application aims to overcome the shortcomings of the prior art and provide a shell opening solution for Crassostrea angulata and application thereof, in order to reduce the food safety risks caused by manual shell opening and apply it to the field of aquatic product processing.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows:

[0006] In a first aspect, the present application provides a shell opening solution for Crassostrea angulata, which comprises 0.5 mol / L-0.6 mol / L magnesium chloride solution and / or 0.5 mol / L-0.6 mol / L glucose solution.

[0007] The shell opening solution of the oyster of Fujian of the present application uses magnesium ion salt solution to paralyze the living body of the oyster of Fujian, and the magnesium ion can block the action of the nerve and muscle of the oyster; the living body of the oyster of Fujian is treated by using glucose solution, and the oyster shell closing muscle is inactivated after the osmotic pressure environment of the water body is changed, so that the purpose of opening the shell is achieved, the possibility of rancidity of the oyster raw material is reduced, and the quality and flavor change of the oyster meat after opening the shell are more optimal.

[0008] As a preferred embodiment of the shell opening solution of the oyster of Fujian of the present application, the volume ratio of the magnesium chloride solution and the glucose solution is 1:1.5-2.

[0009] Preferably, the volume ratio of the magnesium chloride solution and the glucose solution is any one or the range value of two of 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2.

[0010] In the second aspect, the present application provides a shell opening method of the oyster of Fujian, the oyster of Fujian is mixed with the shell opening solution, and soaked for 4h-8h; 5-10 oysters of Fujian are soaked per 1L of the shell opening solution.

[0011] Preferably, the soaking time is any one or the range value of two of 4h, 5h, 6h, 7h, 8h; the number of oysters of Fujian soaked per 1L of the shell opening solution is any one or the range value of two of 5, 6, 7, 8, 9, 10.

[0012] In the third aspect, the present application provides a preparation method of oyster juice, which comprises the following steps:

[0013] (1) The oyster of Fujian is treated by using the shell opening method; the oyster meat is taken out after the shell is opened, soaked in clean water and then drained;

[0014] (2) The drained oyster meat is added with water, homogenized to obtain oyster raw material slurry; trypsin is added for enzymatic hydrolysis; enzyme is inactivated to obtain an enzyme hydrolysate;

[0015] (3) The enzyme hydrolysate is centrifuged to obtain an enzyme hydrolysate supernatant, which is the oyster juice.

[0016] As a preferred embodiment of the preparation method of the oyster juice of the present application, in step (1), the soaking time is 0.5h-1.5h.

[0017] Preferably, the soaking time is any one or the range value of two of 30min, 40min, 50min, 60min, 70min, 80min, 90min.

[0018] As a preferred embodiment of the preparation method of the oyster juice of the present application, in step (2), the amount of water added is 4-6 times the mass of the drained oyster meat.

[0019] Preferably, the amount of water added is any one or a range value of two of 4, 4.5, 5, 5.5, 6 times the mass of the drained oyster meat;

[0020] And / or, the amount of trypsin added is 0.3%-0.8% of the mass of the oyster raw material slurry;

[0021] Preferably, the amount of trypsin added is any one or a range value of two of 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8% of the mass of the oyster raw material slurry;

[0022] And / or, the pH of the enzymatic hydrolysis is 7.0-9.0, the temperature is 50°C-55°C, and the time is 1h-2h;

[0023] Preferably, the pH of the enzymatic hydrolysis is any one or a range value of two of 7.0, 7.5, 8.0, 8.5, 9.0; the temperature is any one or a range value of two of 50°C, 51°C, 52°C, 53°C, 54°C, 55°C; and the time is any one or a range value of two of 1h, 1.5h, 2h;

[0024] And / or, the temperature of the enzyme inactivation is 90°C-100°C, and the time is 5min-15min;

[0025] Preferably, the temperature of the enzyme inactivation is any one or a range value of two of 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, 96°C, 97°C, 98°C, 99°C, 100°C; and the time is any one or a range value of two of 5min, 6min, 7min, 8min, 9min, 10min, 11min, 12min, 13min, 14min, 15min.

[0026] As a preferred embodiment of the method for preparing oyster juice according to the present application, in step (3), the centrifugation is at a speed of 3000r / min-5000r / min for 15min-25min.

[0027] Preferably, the speed is any one or a range value of two of 3000r / min, 3500r / min, 4000r / min, 4500r / min, 5000r / min; and the time is any one or a range value of two of 15min, 16min, 17min, 18min, 19min, 20min, 21min, 22min, 23min, 24min, 25min.

[0028] In a fourth aspect, the application provides application of the shell-opening solution in aquatic product processing.

[0029] In a fifth aspect, the application provides oyster juice prepared by the method for preparing oyster juice.

[0030] In a sixth aspect, the application provides application of the oyster juice in preparing oyster sauce.

[0031] Compared with the prior art, the application analyzes the influence of different ionic salt solutions or organic solutions on the shell-opening effect of Fujian oysters and the change trend of oyster meat quality after shell opening by different solvents, and develops more suitable and safer solution concentration and type for shell opening suitable for aquatic product processing of Fujian oysters.

[0032] The application has the following beneficial effects:

[0033] 1. The application uses magnesium ion salt solution and glucose organic solution to paralyze the living body of Fujian oysters before shell opening, which is used for the first time in aquatic product processing, reduces the food safety risk of manually opening oysters to obtain meat, improves the shell opening and meat obtaining efficiency of Fujian oysters, reduces manual work, and the opening rate of oysters using the biological shell opening method can reach more than 90%.

[0034] 2. The oyster meat obtained by using the shell opening solution has higher yield, no salt ion residue, and meets various indicators of aquatic product processing, and the oyster juice prepared from the oyster meat has better quality, flavor and preservative power. DETAILED DESCRIPTION

[0035] To better illustrate the purposes, technical solutions and advantages of the application, the application will be further described below in combination with specific examples. Those skilled in the art should understand that the specific examples described herein are only used to explain the application, and are not used to limit the application.

[0036] Unless otherwise specified, the test methods used in the examples are conventional methods; and the materials, reagents, etc. used are commercially available unless otherwise specified.

[0037] The raw materials used in the following examples and comparative examples are described as follows, but are not limited to these materials:

[0038] The oysters are purchased from Zhaonan Sea Area, Zhangzhou City, Fujian Province, and are Fujian oysters with a shell height of more than 7 cm;

[0039] Magnesium chloride hexahydrate (MgCl2.6H2O, food grade), potassium chloride (KCl, food grade), magnesium sulfate heptahydrate (MgSO4.7H2O, food grade), sodium chloride (NaCl, food grade), glucose (C6H 12 O6, food grade), trypsin (≥2500 U / mg), are all commercially available.

[0040] Example 1: A solution and method for opening shell of Crassostrea hongkongensis

[0041] (1) Preparation of the solution: Weigh the magnesium chloride hexahydrate and dissolve it in 1L of filtered freshwater to prepare a solution with a magnesium chloride concentration of 0.5mol / L-0.6mol / L.

[0042] (2) The method for opening shell is to mix the Crassostrea hongkongensis and the prepared solution, and soak until the double shell of the oyster is opened; the ratio is 1L of the solution for every 5-6 oysters.

[0043] Example 2: A solution and method for opening shell of Crassostrea hongkongensis

[0044] (1) Preparation of the solution: Weigh the glucose and dissolve it in 1L of filtered freshwater to prepare a solution with a glucose concentration of 0.5mol / L-0.6mol / L.

[0045] (2) The method for opening shell is to mix the Crassostrea hongkongensis and the prepared solution, and soak until the double shell of the oyster is opened; the ratio is 1L of the solution for every 5-6 oysters.

[0046] Example 3: A method for preparing oyster juice

[0047] (1) Preparation of oyster meat: Take the opened Crassostrea hongkongensis from Example 1 or Example 2, remove the oyster meat, soak in clean water for 0.5h-1h, and then drain;

[0048] (2) Enzymatic hydrolysis: Take the drained oyster meat, add distilled water according to a solid-liquid ratio of 1:5, and homogenize in a homogenizer to obtain oyster raw material slurry; adjust the pH to 8.0, add 0.5% of trypsin based on the mass of the oyster raw material slurry, stir thoroughly, and enzymatically hydrolyze in a constant-temperature water bath at 50℃-55℃ for 1.5h-2h; take the enzymatically hydrolyzed oyster raw material slurry, boil in a 100℃ water bath for 10min to inactivate the enzyme, remove, cool to room temperature, and obtain an enzymatic hydrolysate;

[0049] (3) Centrifugation: Centrifuge the enzymatic hydrolysate at 4000r / min for 20min to obtain an enzymatic hydrolysate supernatant.

[0050] Test Example 1: Effect of different shell-opening solutions on the shell-opening rate and opening height of Crassostrea hongkongensis

[0051] (1) Different concentrations of magnesium chloride solution

[0052] Prepare 0.4mol / L, 0.5mol / L, 0.6mol / L, 0.7mol / L, and 0.8mol / L magnesium chloride solutions according to the method of Example 1; take 10L of each magnesium chloride solution to soak 100 fresh and live Crassostrea hongkongensis; after 2h of soaking, count the shell-opening rate of each group, and measure the opening height using a vernier caliper;

[0053] The opening rate (%) = the number of oysters with open shells / the total number of oysters.

[0054] The results are shown in Table 1:

[0055] Table 1 Effect of different concentrations of magnesium chloride on the opening rate and opening height of Fujian oysters

[0056] Magnesium chloride solution concentration (mol / L) Opening rate (%) Average opening height (mm) 0.4 40％ 4±1 0.5 63％ 6±1 0.6 65％ 6±1 0.7 60％ 6±1 0.8 64％ 6±1

[0057] (2) Different soaking times

[0058] Take the prepared 0.6 mol / L magnesium chloride solution; take 10 L of the prepared magnesium chloride solution to soak 100 fresh and live Fujian oysters, and the soaking time is 2 h, 4 h, 5 h, 6 h, and 8 h, respectively. After soaking, the opening rate of each group is counted, and the opening height is measured using a vernier caliper; the results are shown in Table 2:

[0059] Table 2 Effect of different soaking times on the opening rate and opening height of Fujian oysters

[0060] Soaking time (h) Opening rate (%) Average opening height (mm) 2 65％ 6±1 4 80％ 6±1 5 90％ 9±1 6 95％ 10±1 8 93％ 10±1

[0061] (3) Different salt solutions

[0062] Referring to the method of Example 1, 0.6 mol / L sodium chloride solution, potassium chloride solution, and magnesium sulfate solution are prepared respectively; 10 L of each prepared solution is used to soak 100 fresh and live Fujian oysters; after soaking for 6 h, the opening rate of each group is counted, and the opening height is measured using a vernier caliper; the results are shown in Table 3:

[0063] Table 3 Effect of different salt solutions on the opening rate and opening height of Fujian oysters

[0064] Salt solution Opening rate (%) Average opening height (mm) Sodium chloride 25％ 2±1 Potassium chloride 30％ 2±1 Magnesium sulfate 60％ 4±1

[0065] (4) Different concentrations of glucose solution

[0066] Referring to the method of Example 2, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, and 0.8 mol / L glucose solutions are prepared respectively; 20 L of each prepared glucose solution is used to soak 100 fresh and live Fujian oysters; after soaking for 2 h, the opening rate of each group is counted, and the opening height is measured using a vernier caliper; the results are shown in Table 4:

[0067] Table 4 Effect of different concentrations of glucose solution on the opening rate and opening height of Fujian oysters

[0068] Opening solution concentration (mol / L) Opening rate (%) Average opening height (mm) 0.4 35％ 4±1 0.5 66％ 5±1 0.6 63％ 5±1 0.7 60％ 5±1 0.8 61％ 5±1

[0069] (5) Different soaking times

[0070] Table 5 Effects of different soaking time on the shell opening rate and opening height of Fujian oysters

[0071] Table 5 Effects of different soaking time on the shell opening rate and opening height of Fujian oysters

[0072] Soaking time (h) Opening rate (%) Average opening height (mm) 2 65％ 6±1 4 85％ 8±1 5 82％ 7±1 6 78％ 7±1 8 80％ 8±1

[0073] Test Example 2: Effects of different shell opening solutions on the meat quality of Fujian oysters

[0074] (1) Different concentrations of magnesium chloride solution

[0075] The magnesium chloride solutions with concentrations of 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, and 0.8 mol / L were prepared according to the method of Example 1. Each of the prepared magnesium chloride solutions was used to soak 100 fresh Fujian oysters for 6 h. After soaking, the oyster meat was soaked in clean water for 1 h and then drained. The oyster meat of Fujian oysters opened by normal artificial method was used as the control group, and the oyster meat opened by artificial method was exposed in air for about 5 h to simulate the normal temperature treatment time of oyster meat after opening in traditional processing, and the natural oxidation was observed to provide baseline data for microbial proliferation. The total bacterial count (GB 4789.2-2022), Mg ion concentration (GB 5009.268-2016, first method), volatile base nitrogen (GB 5009.228-2016), and crude protein content (Kjeldahl nitrogen determination method) of the oyster meat were detected. The detection results are shown in Table 6:

[0076] Table 6 Effects of different concentrations of magnesium chloride shell opening solution on the meat quality of Fujian oysters

[0077]

[0078] The results showed that there was no significant difference in Mg ion residue and crude protein content in the oyster meat after soaking and opening with different concentrations of magnesium chloride solution compared with the control group, but the total bacterial count and volatile base nitrogen were significantly lower than those of the control group.

[0079] (2) Different concentrations of glucose solution

[0080] The method of Example 2 was referred to prepare 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L glucose solution respectively; 20 L of each prepared glucose solution was used to soak 100 fresh and live Fujian oysters; after soaking for 4 h, the oyster meat was taken out, soaked in clean water for 1 h and then drained; the total number of colonies (GB 4789.2-2022), volatile base nitrogen (GB 5009.228-2016) and crude protein content (Kjeldahl method) of the oyster meat were detected; the oyster meat of Fujian oyster with normal artificial shelling was used as a control group, and the oyster meat after artificial shelling was exposed to air for about 5 h. The detection results are shown in Table 7:

[0081] Table 7 Influence of different concentrations of glucose shelling solution on the quality of Fujian oyster meat

[0082]

[0083] The results showed that the crude protein content of the oyster meat after soaking and shelling in different concentrations of glucose solution had no significant difference with the control group, but the total number of colonies and volatile base nitrogen were significantly lower than those of the control group.

[0084] Test Example 3: Influence of different shelling solutions on the enzymatic oyster juice prepared from Fujian oyster

[0085] (1) Different concentrations of magnesium chloride solution

[0086] The method of Example 1 was referred to prepare 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L magnesium chloride solution respectively; 10 L of each prepared magnesium chloride solution was used to soak 100 fresh and live Fujian oysters; after soaking for 6 h, the oyster meat was taken out, soaked in clean water for 1 h and then drained; the oyster meat of Fujian oyster with normal artificial shelling was used as a control group;

[0087] The drained oyster meat and the oyster meat of the control group were taken, and distilled water was added according to the solid-liquid ratio of 1:5 to obtain oyster raw material slurry in a homogenizer; the pH was adjusted to 8.0, 0.5% of trypsin was added to the oyster raw material slurry, stirred thoroughly, and enzyme hydrolysis was carried out in a 50℃ constant temperature water bath for 2 h; the oyster raw material slurry after enzyme hydrolysis was taken to a 100℃ boiling water bath for 10 min to inactivate the enzyme, taken out and cooled to room temperature to obtain enzyme hydrolysate; the enzyme hydrolysate was centrifuged at 4000 r / min for 20 min to obtain enzyme hydrolyzed oyster juice.

[0088] The following indexes of the enzyme hydrolyzed oyster juice were detected:

[0089] 1) Amino acid nitrogen content: according to GB 5009.235, detected by titrator;

[0090] 2) Sensory evaluation: Organoleptic evaluation of the prepared enzymatic oyster juice flavor was performed by 8 professional organoleptic evaluation personnel with seasoning professional knowledge. The total score of sensory evaluation was 10, and the higher the score, the better the flavor.

[0091] 3) DPPH free radical scavenging rate detection: The enzymatic oyster juice sample was centrifuged at 12000g for 3min, and a number of samples of different concentrations were prepared: 4mg / mL, 8mg / mL, 12mg / mL, 16mg / mL, 20mg / mL, and their antioxidant activities were determined. 500μL sample was added with 500μL 0.2mmoL / L DPPH ethanol solution, and after 30min of light reaction, 1000r / min centrifugation was performed for 10min, and the absorbance was measured at A517, and the results were calculated with the measurement values of the blank group and the control group.

[0092] The detection results are shown in Tables 8 and 9:

[0093] Table 8 Amino acid nitrogen content and sensory evaluation score of enzymatic oyster juice

[0094]

[0095] Table 9 DPPH free radical scavenging rate of enzymatic oyster juice

[0096]

[0097]

[0098] (2) Different concentrations of glucose solution

[0099] Referring to the method of Example 2, 0.4mol / L, 0.5mol / L, 0.6mol / L, 0.7mol / L, 0.8mol / L glucose solutions were prepared; 20L of each prepared glucose solution was used to soak 100 fresh and live Fujian oysters; after soaking for 4h, the oyster meat was taken out, soaked in clean water for 1h, and then drained; the oyster meat of normal artificial shelling Fujian oysters was used as a control group;

[0100] The drained oyster meat and the oyster meat of the control group were taken, and distilled water was added according to the solid-liquid ratio of 1:5 to obtain oyster raw material slurry in a homogenizer; the pH was adjusted to 8.0, 0.5% trypsin was added to the oyster raw material slurry, and the mixture was stirred thoroughly, and then enzymolysis was performed in a 50℃ constant temperature water bath for 2h; the oyster raw material slurry after enzymolysis was taken and boiled in a 100℃ water bath for 10min to inactivate the enzyme, and then cooled to room temperature to obtain an enzymatic solution; the enzymatic solution was centrifuged at 4000r / min for 20min to obtain enzymatic oyster juice.

[0101] The following indicators of enzymatic oyster juice were detected:

[0102] 1) Amino acid nitrogen content: according to GB 5009.235, a titrator is used for detection;

[0103] 2) Sensory evaluation: the prepared enzymatic oyster juice flavor is evaluated by sensory evaluation personnel, and 8 professional evaluation personnel with seasoning professional knowledge are required for each group of evaluation. The total score of sensory evaluation is 10 points, and the higher the score, the better the flavor.

[0104] 3) DPPH free radical scavenging rate detection: the enzymatic oyster juice sample is centrifuged at 12000g for 3min, and a certain amount of sample is taken to prepare sample solutions of different concentrations: 4mg / mL, 8mg / mL, 12mg / mL, 16mg / mL, 20mg / mL, respectively. The antioxidant activity is measured. 500μL sample is added to 500μL 0.2mmoL / L DPPH ethanol solution, avoid light reaction for 30min, 1000r / min centrifugation for 10min, measure the absorbance at A517, and calculate the results with the measured values of blank group and control group.

[0105] The detection results are shown in table 10 and table 11:

[0106] Table 10 Amino acid nitrogen content and sensory evaluation score of enzymatic oyster juice

[0107]

[0108] Table 11 DPPH free radical scavenging rate of enzymatic oyster juice

[0109] Group 4 mg / mL 8 mg / mL 12 mg / mL 16 mg / mL 20 mg / mL Artificially shucked (control) 10.62 12.97 25.53 34.54 35.5 0.4 mol / L 15.45 22.45 28.66 40.67 45.23 0.5 mol / L 16.32 18.54 25.34 38.67 43.23 0.6 mol / L 21.22 36.77 49.06 53.54 51.98 0.7 mol / L 20.34 25.44 39.65 48.56 49.54 0.8 mol / L 18.93 28.41 36.52 48.53 49.88

[0110] The above results show that after soaking Fujian oysters in 0.5mol / L-0.6mol / L magnesium chloride solution for 5h-8h, the oysters can be naturally shelled after paralysis, with a shelling rate of >90% and a shelling height of >9mm; after soaking Fujian oysters in 0.5mol / L-0.6mol / L glucose solution for 4h-5h, the oysters can be naturally shelled after inactivation due to osmotic pressure change, with a shelling rate of >82% and a shelling height of >7mm;

[0111] Using the above magnesium chloride solution or glucose solution as shelling solution for biological shelling of Fujian oysters does not affect the quality of oyster meat, and the meat yield and freshness are significantly improved. The meat yield is increased by 12%-15% (meat yield (%)=(shelled oyster meat weight / fresh oyster total weight) x 100%), as shown in table 12. The proportion of volatile basic nitrogen reduction is 45%, and the proportion of total bacterial count reduction is 70%.

[0112] Table 12 Fujian oyster shelling and meat yield

[0113] Group Fresh oyster average weight (g / individual) Average meat weight (g / individual) Meat yield (%) Artificially shucked (control) 50.2±1.5 15.1±0.8 28.1±1.2 0.5 mol / L magnesium chloride 50.5±1.3 18.3±0.6 36.2±1.1 0.6 mol / L magnesium chloride 49.8±1.4 18.9±0.7 37.9±1.3 0.5 mol / L glucose 50.1±1.6 17.6±0.5 35.1±1 0.6 mol / L glucose 49.9±1.2 18.1±0.6 36.3±1.2

[0114] The oyster meat treated by the above-mentioned shell-opening solution is used to prepare enzyme-decomposed oyster juice, the flavor of which is obviously improved, the proportion of amino acid nitrogen is increased by about 20%, and the antioxidant capacity of the enzyme-decomposed oyster juice (20 mg / mL) can reach more than 50%, which has high biological activity.

[0115] Test Example 4: Effect of shell-opening solution on enzyme-decomposed oyster juice prepared from Fujian oysters

[0116] The 0.6 mol / L magnesium chloride solution was prepared according to the method of Reference Example 1; the 0.6 mol / L glucose solution was prepared according to the method of Reference Example 2; 7 L of the magnesium chloride solution and 13 L of the glucose solution were taken to obtain a mixed shell-opening solution, and 100 fresh Fujian oysters were soaked in the mixed shell-opening solution; the oyster meat was taken out after 5 h of soaking, and then soaked in clean water for 1 h and drained; the oyster meat of Fujian oysters opened by normal artificial method was used as a control group.

[0117] The drained oyster meat and the oyster meat of the control group were used to prepare enzyme-decomposed oyster juice according to Test Example 3, and the amino acid nitrogen content and DPPH free radical scavenging rate of the enzyme-decomposed oyster juice were detected, and sensory evaluation was performed.

[0118] The results showed that the amino acid nitrogen content of the enzyme-decomposed oyster juice was 0.52 g / 100 mL, the sensory evaluation score was 9.3, and the sensory description was that the umami flavor was doubled, the layers were rich, and there was no fishy smell.

[0119] The DPPH free radical scavenging rate of the enzyme-decomposed oyster juice is shown in Table 13:

[0120] Table 13: DPPH free radical scavenging rate of enzyme-decomposed oyster juice

[0121] Group 4 mg / mL 8 mg / mL 12 mg / mL 16 mg / mL 20 mg / mL Artificially shucked (control) 10.62 12.97 25.53 34.54 35.5 Mixed shucking solution 32.4 55.7 68.3 72.6 75.2

[0122] The results showed that, compared with the enzyme-decomposed oyster juice prepared by using the magnesium chloride solution and the glucose solution as the shell-opening solution alone, the amino acid nitrogen of the enzyme-decomposed oyster juice prepared in this test example was increased by 57% compared with the control group, which was significantly higher than that treated by the single solution, the DPPH scavenging rate was doubled compared with the control group, and the flavor was better, which was manifested as the retention of umami substances and strong taste richness, and the fishy smell was inhibited.

[0123] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit the protection scope of the present application. Although the present application 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 application can be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present application.

Claims

1. A shucking solution for Crassostrea hongkongensis, characterized in that, The magnesium chloride solution and the glucose solution have a volume ratio of 1:1.5-2.

2. The shucking solution of Crassostrea hongkongensis according to claim 1, characterized in that, The oysters are mixed with the shell-opening solution of claim 1 or 2 and soaked for 4-8 hours; 3. A method for shelling of Crassostrea fluminea, characterized in that, 5-10 oysters are soaked in 1 L of the shell-opening solution. The method comprises the following steps:

4. A method of preparing oyster juice, characterized by, (1) treating the oysters with the shell-opening method of claim 3; After the oysters are shelled, the oyster meat is taken out, soaked in clean water and drained; (2) the drained oyster meat is added with water, homogenized to obtain an oyster raw material slurry, added with trypsin for enzymatic hydrolysis, and treated to inactivate the enzyme to obtain an enzymatic hydrolysis liquid; (3) the enzymatic hydrolysis liquid is centrifuged to obtain an enzymatic hydrolysis clear liquid, which is oyster juice. In step (1), the soaking time is 0.5-1.5 hours.

5. The method of claim 4, wherein the oyster juice is prepared by the steps of: In step (2), the amount of water added is 4-6 times the mass of the drained oyster meat; 6. The method of claim 4, wherein the oyster juice is prepared by the steps of: And / or, the amount of trypsin added is 0.3%-0.8% of the mass of the oyster raw material slurry; And / or, the pH of the enzymatic hydrolysis is 7.0-9.0, the temperature is 50-55℃, and the time is 1-2 hours; And / or, the temperature for inactivating the enzyme is 90-100℃, and the time is 5-15 minutes. In step (3), the centrifugation is performed at a speed of 3000-5000 r / min for 15-25 minutes.

7. The method of claim 4, wherein the oyster juice is prepared by the steps of:

8. Use of the shell-opening solution of claim 1 or 2 in aquatic product processing. obtained by the preparation method of any one of claims 4-7.

9. A clam juice, characterized in that, 10. Use of the oyster juice of claim 9 in preparing oyster sauce. ​

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