Method for removing heavy metals and fishy smell substances from sargassum fusiforme
Through steaming, pickling and microbial fermentation, the problems of heavy metals and fishy smell substances in sausage are solved, effectively reducing heavy metals and removing fishy smells in sausage are achieved, and the flavor of the ingredients is improved.
Patent Information
- Application Number
- CN202510208845.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-25
- Publication Date
- 2025-05-02
AI Technical Summary
The heavy metals enriched in sheep cabbage, especially arsenic, have food safety risks, and their fishy smell substances also affect the edible experience.
The treatment is carried out by cooking, pickling and microbial fermentation. The specific steps include: steaming and cooking the mutton cabbage for 1.5 to 2.5 hours, then mixing it with citric acid solution, pickling treatment, and finally inserting Streptococcus thermophilus into sterile water for microbial fermentation.
Effectively reduce the heavy metal content in sausage, especially arsenic, and reduce the content of fishy smell substances, improving the flavor of sausage.
Smart Images
Figure CN119908448A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a method for removing heavy metals and fishy smell substances from Sargassum fusiformis, belonging to the technical field of heavy metal removal from aquatic products. Background Art
[0002] Sargassum fusifarme is a plant of the genus Sargassum in the family Sargassum, which is widely distributed in the Bohai Sea, the Yellow Sea, the East China Sea, the South China Sea, etc. Sargassum fusifarme has an excellent taste and is rich in nutrients such as iodine, phosphorus, iron, protein, vitamins, etc. It also has the effects of nourishing blood, lowering blood pressure, facilitating bowel movements, softening hard masses and reducing phlegm, etc. It is a popular food ingredient and can be used for cold salads, stir-frying, steaming, hot pot, etc.
[0003] With the development of industrialization and the increase of human activities, heavy metal pollution in the atmosphere, water, soil and other environments has become increasingly serious, among which the problem of heavy metal pollution in the water environment is particularly prominent. Heavy metal pollution in the water environment has caused varying degrees of damage to the aquatic ecology. Seaweed is an important observer of heavy metal pollution, and algae have a particularly strong ability to enrich certain heavy metals. Sargassum has a strong ability to enrich arsenic, and the content of highly toxic inorganic arsenic is relatively high. Therefore, for food safety considerations, it is necessary to remove heavy metals from Sargassum. Summary of the invention
[0004] In view of the above-mentioned prior art, the present invention provides a method for removing heavy metals and fishy odor substances from Sargassum fusiformis.
[0005] The present invention is achieved through the following technical solutions: A method for removing heavy metals and fishy substances from Sargassum fusiformis, comprising the following steps: (1) Steaming: Take the Sargassum fusiformis, place it in water, and steam it for 1.5 to 2.5 hours to obtain the steamed Sargassum fusiformis; (2) Pickling: the steamed Sargassum fusiformis is mixed with 0.6% to 1.0% (mass to volume ratio, g / ml) citric acid solution, with a solid-liquid ratio of 1:3 to 5 (kg:L), and stirred at 60 to 80°C for 1.5 to 2.5 hours to obtain pickled Sargassum fusiformis; (3) Microbial fermentation: Mix the pickled Sargassum fusiformis with sterile water at a solid-liquid ratio of 1:3-5 (kg:L), inoculate with thermophilic Streptococcus, ferment at 37°C for 2-7 days, and then wash.
[0006] Furthermore, the heavy metal is any one or more of arsenic, chromium and cadmium.
[0007] Furthermore, in the step (1), the seaweed is fresh seaweed or soaked dried seaweed.
[0008] Furthermore, in the step (1), the Sargassum fusiformis is cut into small segments of 1 to 2 cm in length.
[0009] Furthermore, in the step (1), the cooking time is 2 hours.
[0010] Furthermore, in step (2) or step (3), the material-liquid ratio is 1:4.
[0011] Furthermore, in step (2), the concentration of the citric acid solution is 0.64%.
[0012] Furthermore, in the step (2), the temperature is 70°C.
[0013] Furthermore, in the step (2), the processing time is 2 hours.
[0014] Furthermore, in step (3), the fermentation time is 5 days or 7 days.
[0015] The method for removing heavy metals and fishy substances from Sargassum fusiformis of the present invention can effectively remove heavy metals, especially arsenic, from Sargassum fusiformis and can also effectively reduce the content of fishy substances, thereby achieving the effects of removing fishy smell, increasing fragrance and improving the flavor of Sargassum fusiformis.
[0016] Various terms and phrases used herein have the general meanings that are well known to those skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 : Schematic diagram of the effect of cooking time on the arsenic content in Sargassum fusiformis, where letters are used to indicate significant differences, the same below.
[0018] Figure 2 : Schematic diagram of the effect of cooking time on the chromium content in Sargassum fusiformis.
[0019] Figure 3 : Schematic diagram of the effect of cooking time on the cadmium content in Sargassum fusiformis.
[0020] Figure 4 : Schematic diagram of the effect of citric acid concentration on the arsenic content in Sargassum fusiformis.
[0021] Figure 5 : Schematic diagram of the effect of pickling temperature on the arsenic content in Sargassum fusiformis.
[0022] Figure 6 : Schematic diagram of the effect of pickling time on the arsenic content in Sargassum fusiformis.
[0023] Figure 7 : Schematic diagram of Box-Behnken experimental factors and level design, where A is the contour map and 3D map of the interaction between concentration and temperature, B is the contour map and 3D map of the interaction between temperature and time, and C is the contour map and 3D map of the interaction between concentration and time.
[0024] Figure 8 :Schematic diagram of the effect of fermentation time on the arsenic content in Sargassum fusiformis.
[0025] Fig. 9 : Schematic diagram of the effect of fermentation time on the chromium content in Sargassum fusiformis.
[0026] Fig.10 : Schematic diagram of the effect of fermentation time on the cadmium content in Sargassum fusiformis. DETAILED DESCRIPTION
[0027] The present invention will be further described below in conjunction with the embodiments. However, the scope of the present invention is not limited to the following embodiments. It will be appreciated by those skilled in the art that various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention.
[0028] The instruments, reagents, and materials involved in the following examples, unless otherwise specified, are all conventional instruments, reagents, and materials available in the prior art and can be obtained through regular commercial channels. The experimental methods, detection methods, etc. involved in the following examples, unless otherwise specified, are all conventional experimental methods and detection methods available in the prior art.
[0029] The method for detecting the content of heavy metals (including arsenic, chromium and cadmium) in Sargassum fusiformis of the present invention refers to "SN / T 0448-2011".
[0030] The method for detecting the content of fishy substances in Sargassum fusiformis of the present invention is as follows: automatic sampling system: weigh 2 g of sample into a 20 mL headspace glass injection bottle, and use GC-IMS to analyze its volatile flavor substances. The injection bottle is placed on the sample rack, incubated at 50°C for 10 min, the incubation speed is 500 rpm, the automatic injection needle draws 500 μL of gas for injection, the injector temperature is 55°C, and the injection speed is 60 mL / min.
[0031] GC system conditions: The instrument analysis used a polar chromatographic column MXT-WAX (15 m×0.53 mm ID, 1.0 μm df, GAS, dortmund, Germany), the column temperature was 40°C, the temperatures before and after the chromatographic column transfer tube were 80°C and 50°C, respectively, and high-purity nitrogen was used as the carrier gas. The carrier gas flow rate was E2, the initial flow rate was 2 mL / min, the analysis was 2 min; it was increased to 10 mL / min, the analysis was 3 min; then it was increased to 15 mL / min, the analysis was 10 min; then it was increased to 50 mL / min, the analysis was 5 min; and finally it was increased to 150 mL / min, the analysis was 5 min. The total analysis time was 25 min.
[0032] IMS system conditions: drift tube length of 98 mm, temperature of 45 °C. Flow rate of 150 mL / min and kept constant. The radioactive source in the drift tube was deuterium, the gas was high-purity nitrogen, and the ionization was set to positive ion mode. Ortho-ketones (C4-C9) were used as external standards to prepare calibration curves under the same analytical conditions to calibrate the retention index of volatile organic compounds. The volatile components of the samples were collected using the instrument's built-in LAV software, and the compounds were qualitatively analyzed in combination with the GC×IMS Library Search software database.
[0033] The thermophilic streptococcus used in the present invention is a conventional strain in the prior art and can be purchased conventionally from Xi'an Mixianer Company.
[0034] Experiment 1 Study on the method of removing heavy metals from Sargassum fusiformis (1) Steaming: Take dried seaweed (soaked), wash, cut into small pieces 1 to 2 cm long, place in water, and steam for 0.5 to 2.5 hours to obtain steamed seaweed; The effects of cooking time (5 levels: 0.5 h, 1.0 h, 1.5 h, 2.0 h, 2.5 h; uncooked Sargassum fusiformis was used as control) on the contents of heavy metals (As, Cr, Cd) in Sargassum fusiformis were investigated. Figure 1 , Figure 2 , Figure 3 As shown in the figure, it can be seen that when the cooking time is 2 hours and 2.5 hours, the removal effect of heavy metals is excellent and there is a significant difference.
[0035] The cooking time was selected as 2 h for subsequent investigation.
[0036] (2) Pickling: Mix the steamed Sargassum fusiformis with citric acid solution (concentration of 0.2% to 1.0%) at a solid-liquid ratio of 1:4 (kg:L) and stir at 50°C for 2 hours.
[0037] The citric acid solutions of various concentrations are prepared with food-grade citric acid and sterile water.
[0038] (a) The effect of citric acid concentration (five levels: 0.2%, 0.4%, 0.6%, 0.8%, 1.0%; uncooked Sargassum fusiformis was used as the control) on the arsenic content in Sargassum fusiformis was investigated. The results are as follows: Figure 4 As shown in the figure, it can be seen that when the citric acid concentration is 0.6% to 1.0%, the effect is excellent and there is a significant difference.
[0039] The citric acid concentration of 0.6% was selected for subsequent investigation.
[0040] (b) The effect of pickling temperature (6 levels: 40℃, 50℃, 60℃, 70℃, 80℃, 90℃; uncooked Sargassum fusiformis was used as control) on the arsenic content in Sargassum fusiformis was investigated. The results are as follows: Figure 5 As shown in the figure, it can be seen that when the temperature is 60-90°C, the effect is excellent and there is a significant difference.
[0041] The temperature was selected as 60°C for subsequent investigation.
[0042] (c) The effect of pickling time (five levels: 0.5 h, 1.0 h, 1.5 h, 2.0 h, 2.5 h; uncooked Sargassum fusiformis was used as the control) on the arsenic content in Sargassum fusiformis was investigated. Figure 6 As shown in the figure, it can be seen that the pickling time has little effect on the arsenic content and there is no significant difference.
[0043] (d) Citric acid response surface optimization experiment and optimal process verification Pickling temperature, pickling time, and citric acid concentration were selected as experimental factors, and As content was selected as the evaluation index. Design-Expert.V8.0.6 software was used to perform a three-factor three-level response surface experimental analysis to obtain a regression model. The regression model was used to predict the optimal process parameters for removing arsenic. The factor levels are shown in Table 1, the response surface analysis scheme and experimental results are shown in Table 2, and the regression model and variance analysis are shown in Table 3. Using Design-Expert.V8.0.6 software to perform a multivariate regression fitting analysis on the data in Table 1, the regression equation can be obtained as follows: Y=64.93424-0.72861A-24.34167B-6.42333C-0.12167AB-0.02333AC-2.37500BC+0.0056778A 2 +27.68750B 2 +2.28750C 2 The verification test was carried out under the optimal process parameters and repeated several times to determine the As content. The verification test results were compared with the predicted values of the regression model to determine the accuracy and reliability of the regression model.
[0044]
[0045]
[0046]
[0047] Note: R2=0.9938, R2Adj=0.9859, * indicates significant difference (P<0.05), ** indicates extremely significant difference (P<0.01).
[0048] The citric acid pickling process parameters predicted by the regression model were temperature 70.78℃, pickling time 1.9191 hours, citric acid concentration 0.6414%, and the lowest predicted As value was 22.172 mg / kg. For the convenience of operation, the optimized conditions were changed to: temperature 70℃, pickling time 2 hours, pickling concentration 0.64%. Three parallel experiments were carried out under this optimized condition, and the As content was 22.03 mg / kg±1.21 mg / kg, which was close to the predicted value, indicating that the optimized process parameters were accurate and reliable.
[0049] (3) Microbial fermentation: After the above-mentioned steaming (steaming time is 2 hours) and pickling (the concentration of the citric acid solution is 0.64%, the temperature is 70°C, and the treatment time is 2 hours), the pickled Sargassum fusiformis is obtained; the pickled Sargassum fusiformis is mixed with sterile water at a solid-liquid ratio of 1:4 (kg:L), and the thermophilic Streptococcus seed solution is inoculated at an inoculation amount of 5% (volume percentage), and fermented at 37°C for 2 to 7 days, and then washed.
[0050] The thermophilic streptococcus seed liquid is obtained by the following method: thermophilic streptococcus powder is mixed with sterile water at a solid-liquid ratio of 1:200 (g:ml), and activated at 37° C. for 1 hour to obtain the seed liquid.
[0051] The effects of fermentation time (3 levels: 2 days, 5 days, and 7 days; uncooked Sargassum fusiformis was used as the control) on the contents of heavy metals (As, Cr, and Cd) in Sargassum fusiformis were investigated. Figure 8 , Fig. 9 , Fig.10 As shown in the figure, when the fermentation time is 7 days, the removal effect of heavy metals is excellent and there is a significant difference. The influence of fermentation time on the relative content of fishy substances in Sargassum is shown in Table 4. As can be seen from Table 4, after 2 days, 5 days and 7 days of fermentation with 5% thermophilic Streptococcus, the content of important fishy substances is significantly reduced compared with the untreated sample. Comprehensive observation shows that the content of various fishy substances decreases the most after 5 days of fermentation.
[0052]
[0053] (4) Conclusion The use of steaming, pickling, and microbial fermentation can effectively reduce the content of heavy metals in Sargassum, especially arsenic. The principle of removing heavy metals is that Sargassum will release heavy metal ions into surface water droplets in a steam environment, and the water droplets drip into the bottom of the pot under the action of gravity. Citric acid is a strong chelating agent. Metal ions combine with citric acid and enter the solution. After filtering, Sargassum with low heavy metal content can be obtained. The surface of microorganisms can adsorb heavy metal ions, and the channels on the surface will also transport heavy metals into the cells. After the Sargassum is washed after microbial fermentation, the heavy metal content will drop significantly. The combination of the three methods can significantly reduce the heavy metal content of Sargassum. At the same time, it was unexpectedly found that it can also effectively reduce the content of fishy substances, which has the effect of removing fishy smell, increasing fragrance, and improving the flavor of Sargassum.
[0054] The above examples are provided to those skilled in the art to fully disclose and describe how to make and use the claimed embodiments, and are not intended to limit the scope of the disclosure herein. Modifications that are obvious to those skilled in the art will fall within the scope of the appended claims.
Claims
1. A method for removing heavy metals and fishy odor substances from Sargassum fusiformis, characterized in that: The following steps are involved: (1) Steaming: Take the Sargassum fusiformis, place it in water, and steam it for 1.5 to 2.5 hours to obtain the steamed Sargassum fusiformis; (2) Pickling: mixing the steamed Sargassum fusiformis with 0.6% to 1.0% citric acid solution at a solid-liquid ratio of 1:3 to 5, stirring at 60 to 80° C. for 1.5 to 2.5 hours to obtain pickled Sargassum fusiformis; (3) Microbial fermentation: Mix the pickled Sargassum with water at a solid-liquid ratio of 1:3-5, inoculate with thermophilic Streptococcus, ferment at 37°C for 2-7 days, and then wash.
2. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: The heavy metal is any one or more of arsenic, chromium and cadmium.
3. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: In the step (1), the sea bream is fresh sea bream or soaked dried sea bream.
4. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: In the step (1), the seaweed is cut into small pieces of 1 to 2 cm in length.
5. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: In the step (1), the cooking time is 2 hours.
6. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: In step (2) or step (3), the material-liquid ratio is 1:
4.
7. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: In the step (2), the concentration of the citric acid solution is 0.64%.
8. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: In the step (2), the temperature is 70°C.
9. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: In the step (2), the processing time is 2 hours.
10. The method for removing heavy metals and fishy odor substances from Sargassum fusiformis according to claim 1, characterized in that: In the step (3), the fermentation time is 5 days or 7 days.