Instant leisure kelp and preparation method thereof

Abstract

The invention discloses a preparation method of instant leisure kelp. The preparation method comprises the following steps: rehydration: soaking dried kelp blocks in water at 20-25 DEG C, and rehydrating for about 15 minutes; performing fermentation treatment: inoculating lactobacillus plantarum into the rehydrated kelp blocks, and performing fermentation at room temperature; boiling with water: putting the fermented kelp blocks into boiled water for blanching; and seasoning: adding monosodium glutamate, sugar and plum powder into the blanched kelp blocks, uniformly mixing, standing and pickling to obtain the instant kelp. According to the method, cell walls of the kelp are destroyed by lactobacillus plantarum in the fermentation process, so that plum powder and other seasonings can permeate into the kelp more easily, the plum powder and the other seasonings are combined to play a role, the kelp is endowed with unique flavor and taste, and the instant leisure kelp product has the characteristics of being ready to eat and convenient to carry when a bag is opened.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to instant leisure kelp and a preparation method thereof. Background Art

[0002] Kelp is an important renewable marine biological resource with low cost and rich nutrition. It is widely used in food, biomedicine, medicine, daily chemical industry and other fields. Kelp is rich in amino acids and has a unique and strong seaweed flavor. It is an excellent natural seasoning raw material. It also contains rich kelp polysaccharides such as sodium alginate, fucoidan, laminarin, etc. Kelp is low in calories, moderate in protein, and rich in minerals. It is an ideal natural marine food. However, the taste of kelp itself is relatively simple and has a relatively serious fishy smell, which affects the quality of the product and consumer acceptance.

[0003] In the related art, for example, invention patent application CN 108740850 A uses lactic acid bacteria to ferment kelp to produce instant kelp, which improves the taste of the instant kelp and increases its nutritional value. However, the taste is still relatively simple, and it is difficult to season the kelp well to produce an instant kelp product with a unique flavor. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an instant leisure kelp and a preparation method thereof. The kelp is fermented with Lactobacillus plantarum, which can reduce the fishy smell of the kelp itself and destroy the cell wall, so that plum powder and other seasonings can more easily penetrate into the kelp, giving the kelp a unique flavor and taste.

[0005] To achieve the above object, the present invention provides a method for preparing instant leisure kelp, which comprises:

[0006] Rehydration: Soak the dried kelp pieces in 20℃~25℃ water for about 15 minutes;

[0007] Fermentation treatment: inoculate Lactobacillus plantarum into the rehydrated kelp blocks and ferment at room temperature;

[0008] Boiling: Blanch the fermented kelp pieces in boiling water;

[0009] Seasoning: Add MSG, sugar and plum powder to the blanched kelp blocks, mix well, let it stand and marinate to get ready-to-eat kelp.

[0010] According to an embodiment of the present invention, a method for preparing instant leisure kelp is provided. In this method, Lactobacillus plantarum destroys the cell wall of the kelp during the fermentation process, so that plum powder and other seasonings can more easily penetrate into the interior of the kelp. The two work in combination to give the kelp a unique flavor and taste, and the kelp is processed into an instant leisure kelp product, which has the characteristics of being ready to eat after opening the bag and convenient to carry. At the same time, Lactobacillus plantarum can be promoted to play a prebiotic role, regulate intestinal peristalsis, and promote the human body's digestive ability.

[0011] Optionally, during the fermentation treatment, the inoculation amount of Lactobacillus plantarum is 2% (v / v) and the fermentation time is 4 hours.

[0012] Optionally, during boiling, a single factor test is used to set the blanching time to 5 min, 10 min, 15 min, 20 min, and 25 min, respectively, and the optimal boiling time is selected as 5 min to 15 min based on the sensory score.

[0013] Optionally, when seasoning, the amount of plum powder added is set to 2% (g / g), 4% (g / g), 6% (g / g), 8% (g / g), and 10% (g / g), respectively. Taking sensory evaluation as an indicator, the best amount of plum powder added is selected as 2% (g / g) to 6% (g / g).

[0014] Optionally, when seasoning, a single factor experiment is used to set the marinating time to 15 min, 30 min, 45 min, 60 min, and 75 min, respectively, and sensory evaluation is used as an indicator to select the best marinating time of 15 min to 45 min.

[0015] On the other hand, the present invention provides instant leisure kelp prepared by the above preparation method. The instant leisure kelp is ready to eat after opening the bag and is convenient to carry. It has a unique flavor and taste, and can promote plant lactobacillus to play a probiotic role, regulate intestinal peristalsis, and promote human digestion ability.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The effect of blanching time on instant leisure kelp in the embodiment of the present invention;

[0018] Figure 2 The effect of the amount of plum powder added on the instant leisure kelp in the embodiment of the present invention;

[0019] Figure 3 The effect of pickling time on instant leisure kelp in the embodiment of the present invention;

[0020] Figure 4is an interaction diagram of the pickling time A and the amount of plum powder added B in the embodiment of the present invention;

[0021] Figure 5 is an interaction diagram of the pickling time A and the blanching time C in an embodiment of the present invention;

[0022] Figure 6 This is the interaction between the amount of plum powder added B and the blanching time C in the embodiment of the present invention. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is described below through specific examples. It should be understood that the one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combination step or the insertion of other method steps between these explicitly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to limit the scope of the present invention. The change or adjustment of the relative relationship thereof shall also be regarded as the scope of the present invention without substantially changing the technical content.

[0024] In order to better understand the above technical scheme, the exemplary embodiments of the present invention are described in more detail below. Although exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0025] The test materials used in the present invention are all common commercial products and can be purchased in the market.

[0026] In the following examples, 10 professionally trained personnel were randomly selected to form a sensory evaluation team, including 6 women and 4 men. The sensory evaluation standard for instant leisure kelp was formulated with reference to the national standard GBT11784-1989, and the scores were given according to the following standards. The total score of each person was taken and the average of the total score was calculated as the final result. The full score of the sensory evaluation score is 100 points. As shown in Table 1:

[0027] Table 1 Sensory evaluation standards for ready-to-eat leisure kelp

[0028]

[0029] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0030] Example 1

[0031] A method for preparing instant leisure kelp based on a single factor method comprises the following steps:

[0032] Rehydration: Select dry kelp that is clean and flat, with thick leaves, brown to yellowish brown straight parts, no mold, no kelp roots, no sticking between kelp, and no yellow or white tips. Cut into kelp strips after sorting; soak the dry kelp strips in water at 20℃ ~ 25℃ for about 15 minutes to rehydrate.

[0033] Fermentation: Use Lactobacillus plantarum powder and inoculate it on the kelp pieces at an inoculum amount of 2% (v / v), add 50 mL of physiological saline, mix well, and ferment at room temperature for 4 hours.

[0034] Boiling: Blanch the fermented kelp in boiling water.

[0035] Seasoning: Add 0.5 (± 0.1) g of MSG, 1 (± 0.1) g of sugar, plum powder (g / g), etc. into the kelp, mix well, let it stand and marinate, and you will get the ready-to-eat leisure kelp.

[0036] A single factor test was used to evaluate the sensory quality of the instant leisure kelp.

[0037] (1) Single factor experiment of blanching time: The blanching time was set to 5 min, 10 min, 15 min, 20 min, and 25 min respectively; when seasoning, the amount of plum powder added was 4% (g / g); the pickling time was 30 min. Figure 1 As shown, the optimal blanching time is 5 minutes to 15 minutes.

[0038] (2) Single factor experiment of plum powder addition: The blanching time was set to 10 min, the pickling time was set to 30 min, and the addition amount of plum powder was set to 2% (g / g), 4% (g / g), 6% (g / g), 8% (g / g), and 10% (g / g) respectively. Figure 2 As shown, the optimal addition amount of plum powder is 2% (g / g) to 6% (g / g).

[0039] (3) Single factor experiment of pickling time: the blanching time was set to 10 min; the amount of plum powder added during seasoning was set to 4% (g / g); the pickling time was 15 min, 30 min, 45 min, 60 min, and 75 min. Figure 3 As shown, the best marinating time is 15min to 45min.

[0040] Example 2

[0041] Based on Example 1, after completing the above single factor test operation processing steps, the results obtained from the above single factor test were proposed as the optimal level, and a response surface optimization design was performed, and the specific levels were set as shown in Table 2.

[0042] Table 2 Response surface experimental factors and levels

[0043]

[0044] The three-factor three-level experimental design was carried out using Dsign Eepert software according to the Box-Behnken design principle. The experimental plan and response results are shown in Table 3.

[0045] Table 3 Box-Behnken design scheme and response value

[0046]

[0047]

[0048] A prediction model was established with pickling time A, plum powder addition amount B, blanching time C, and sensory score as response values, and a multiple regression equation was established:

[0049] Y=10.00000+1.84867A+12.20875B+5.36850C~0.044167AB~0.016333AC~0.040000BC~0.025533A 2 ~1.305002B 2 ~0.23289C 2

[0050] The above regression equation was subjected to variance analysis, and the results are shown in Table 4.

[0051] Table 4 Significance of response surface and its variance analysis

[0052]

[0053]

[0054] Note: * indicates significant difference, i.e. p<0.05; ** indicates extremely significant difference, i.e. p<0.01.

[0055] Note: *indicates significant difference, p<0.05; **indicates extremely significant difference, p<0.01.

[0056] The response surface analysis of the above regression equation was performed using Design~Expert8.0.6.1 software to obtain the response surface diagram of the factors in the regression equation, as shown in Figures 4 to 6 According to the model analysis and considering the actual feasibility and operability of the experiment, the process conditions for instant leisure kelp are pickling time of 27min to 33min, plum powder addition of 3% (g / g) to 5% (g / g), blanching time of 7min to 11min. Under these conditions, the theoretical value of the sensory evaluation score is 89.0513.

[0057] Example 3

[0058] A method for preparing instant leisure kelp comprises the following steps:

[0059] Rehydration: Select dry kelp that is clean and flat, with thick leaves, brown to yellowish brown straight parts, no mold, no kelp roots, no sticking between kelp, and no yellow or white tips. Cut into kelp strips after sorting; soak the dry kelp strips in water at 20℃ ~ 25℃ for about 15 minutes to rehydrate.

[0060] Fermentation: Use Lactobacillus plantarum powder and inoculate it on the kelp pieces at an inoculation rate of 2% (v / v), add physiological saline, mix well, and ferment at room temperature for 4 hours.

[0061] Boiling: Place the fermented kelp in boiling water and blanch it for 7 to 11 minutes.

[0062] Seasoning: Add 0.5 (± 0.1) g of monosodium glutamate, 1 (± 0.1) g of sugar, and 3% (g / g) to 5% (g / g) of plum powder into the kelp, mix well, and marinate for 27 to 33 minutes to obtain the ready-to-eat leisure kelp.

[0063] Three verification experiments were carried out to examine the reliability of the model. The results showed that under the actual optimal process conditions, the sensory score of ready-to-eat kelp was 88.333 points, which was close to the theoretical value. The ready-to-eat kelp product had a compact texture, crisp texture and unique flavor, which further verified that this model is suitable for optimizing the processing technology of ready-to-eat kelp.

[0064] Comparative Example 1

[0065] A method for preparing instant leisure kelp comprises the following steps:

[0066] Rehydration: Select dry kelp that is clean and flat, with thick leaves, brown to yellowish brown straight parts, no mold, no kelp roots, no sticking between kelp, and no yellow or white tips. Cut into kelp strips after sorting; soak the dry kelp strips in water at 20℃ ~ 25℃ for about 15 minutes to rehydrate.

[0067] Fermentation: Use Lactobacillus plantarum powder and inoculate it on the blanched kelp pieces at an inoculation rate of 2% (v / v), add physiological saline, mix well, and ferment at room temperature for 4 hours.

[0068] Boiling: Place the rehydrated kelp in boiling water and blanch it for 7 to 11 minutes.

[0069] Seasoning: Add 0.5 (± 0.1) g of monosodium glutamate, 1 (± 0.1) g of sugar, and 4% (g / g) to 5% (g / g) of plum powder into the kelp, mix well, and marinate for 27 to 33 minutes to obtain the ready-to-eat leisure kelp.

[0070] Comparative Example 2

[0071] A method for preparing instant leisure kelp comprises the following steps:

[0072] Rehydration: Select dry kelp that is clean and flat, with thick leaves, brown to yellowish brown straight parts, no mold, no kelp roots, no sticking between kelp, and no yellow or white tips. Cut into kelp strips after sorting; soak the dry kelp strips in water at 20℃ ~ 25℃ for about 15 minutes to rehydrate.

[0073] Boiling: Place the rehydrated kelp in boiling water and blanch it for 7 to 11 minutes.

[0074] Fermentation: Use plant lactobacillus powder and inoculate it on the blanched kelp blocks at an inoculum amount of 2% (v / v), add the prepared monosodium glutamate 0.5 (±0.1) g, sugar 1 (±0.1) g, 3% (g / g) to 5% (g / g) plum powder, mix well, and ferment at room temperature for 4 hours to obtain the ready-to-eat leisure kelp.

[0075] Test example

[0076] The instant leisure kelp prepared in Example 3, Comparative Example 1 and Comparative Example 2 were subjected to heavy metal content detection, colony count determination, α-glucosidase inhibition analysis and texture analysis.

[0077] Heavy metal content detection: The most common heavy metal pollutants in aquatic products include mercury (Hg), arsenic (As), lead (Pb), cadmium (Cd) and other elements. Heavy metal pollution is gradually causing more harm to the human body. Excessive lead content can cause damage to the nervous system and hematopoietic system in the human body, which is extremely harmful to human health. The intake of trace element lead has the effect of promoting development and enhancing memory, so the detection of lead (Pb) content in kelp is essential. According to the current standard GB5009.268~2016 (first method) in my country, the detection method of Hg, InAs, and Pb (measured in Pb) in food is stipulated, and the inductively coupled plasma mass spectrometry method is used to detect the heavy metal content of ready-to-eat leisure kelp.

[0078] The results are shown in Table 5. The measured value of Pb in the kelp product of Example 3 is 0.0035 mg / kg. According to the national standard GB2762-2022 Limits of Contaminants in Food, the Pb content in algae products should be less than 1 mg / kg. The lead content in Example 3 is much lower than the national standard. This may be due to the change in the microbial regulation of kelp after fermentation with Lactobacillus plantarum, which causes the change in the content of lead in aquatic products. In addition, trace amounts of lead content help maintain the function of the nervous system, indicating that the heavy metal indicators of the kelp products prepared in this application meet the national standards.

[0079] Table 5 Detection limit and quantification limit of inductively coupled plasma mass spectrometry (ICP-MS)

[0080]

[0081] Colony count determination: Colony count determination is to determine the number of microorganisms in the sample by culturing microorganisms and counting the number of colonies in the culture dish. The number of microorganisms indicates the contamination status or hygiene level of the food to a certain extent, and reflects whether the food meets the hygiene requirements. According to GB4789.2-2022 National Food Safety Standard Food Microbiology Inspection Colony Count Determination. Weigh the sample and place it in a sterile homogenizing cup filled with sterile saline for 1min to 2min. Pipette the sample homogenate and the blank homogenate into the plate count agar medium (PCA). After culturing in a constant temperature incubator at 30℃ for 72h, calculate the total colony count. Each experiment should be repeated at least three times in parallel.

[0082] According to the national food safety standard GB19643-2016, algae and its products, the total colony count of algae products should be less than 300 CFU / mL. According to the data in Table 6, the number of live bacteria in the instant leisure kelp of Example 3 is higher than that in Comparative Example 1 and Comparative Example 2, indicating that fermentation destroys the cell wall, allowing probiotics to enter the kelp more effectively, and promoting the increase of the number of live bacteria to 1.82×10 6 CFU / mL, the value meets the colony count standard, indicating that the product is in good sanitary condition and avoids contamination to ensure the stability of product quality.

[0083] Table 6 Colony count

[0084]

[0085] Analysis of α-glucosidase inhibition: α-glucosidase can catalyze the hydrolysis of α-1,4-glycosidic bonds of oligosaccharide substrates to generate glucose. By inhibiting the enzymatic activity of α-glucosidase in the intestine, the hydrolysis of carbohydrates in food to generate glucose can be blocked, thereby reducing postprandial blood sugar levels. The 96-well plate method was used to determine the inhibition of α-glucosidase by the instant leisure kelp combination. The kelp products were homogenized, and the samples were centrifuged at 4000rpm for 20 minutes. The supernatant was taken to determine the inhibitory effect of α-glucosidase and the absorbance value at 405nm was determined.

[0086] The results are shown in Table 7. Compared with the control group, the α-glucosidase inhibition rate of Example 3 increased significantly to 71.8%, indicating that the optimized kelp combination has a certain effect on the inhibition of α-glucosidase.

[0087] Table 7 Inhibition of α-glucosidase

[0088]

[0089] Texture analysis: Texture analysis is performed using a texture analyzer. In the TPA test, the first compression is usually used to measure the hardness and elasticity of the sample, while the second compression can be used to calculate the viscosity and chewiness of the sample. The sensory analysis of instant leisure kelp is further analyzed by measuring the chewiness and elasticity of the instant kelp. The texture probe uses a P / 5R probe, and the TAP mode is used for measurement. The test type is downward pressure, the target mode is displacement, the pre-measurement speed is 1.00mm / s, the post-measurement speed is 1.00mm / s, the test speed is 1.00mm / s, the trigger is =5g, the deformation is 40%, the dwell time between the two compressions is 5s, the data acquisition rate is 400p / s, each sample is measured 6 times in parallel, and the final result is the average value.

[0090] The results are shown in Table 8. Compared with the two groups of control examples, the hardness, crispness and elasticity of the instant kelp product of Example 3 are improved, and the elasticity is moderate. After single factor and response surface optimization, the crispness and chewiness of the instant leisure kelp are relatively moderate, and the sample is in good condition, indicating that the sample has a certain effect after optimization.

[0091] Table 8 Texture analysis

[0092]

[0093] To sum up, according to embodiments of the present invention, by plant lactobacillus destroying the cell wall of kelp during fermentation, plum powder and other seasonings are more easily infiltrated into kelp inside, the two are combined to play a role, giving kelp unique local flavor and mouthfeel, processed into instant leisure kelp product, with the characteristics of bag-opening and convenient to carry. Found by single factor and response surface optimization results, at fermentation time 4h~4.5h, plant lactobacillus inoculum amount 2% (v / v), blanching time 7min~11min, plum powder addition 3% (g / g)~5% (g / g), pickling time 27min~33min conditions, the sensory score value of this kelp reaches the highest, and under this condition, the inhibitory effect of the alpha-glucosidase of instant leisure kelp rises, and the number of viable bacteria also increases.

[0094] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0095] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preparing instant leisure kelp, characterized in that: include: Rehydration: Soak the dried kelp pieces in 20℃~25℃ water for about 15 minutes; Fermentation treatment: inoculate Lactobacillus plantarum into the rehydrated kelp blocks and ferment at room temperature; Boiling: Blanch the fermented kelp pieces in boiling water; Seasoning: Add MSG, sugar and plum powder to the blanched kelp blocks, mix well, let it stand and marinate to get ready-to-eat kelp.

2. The preparation method according to claim 1, characterized in that During the fermentation treatment, the inoculation amount of Lactobacillus plantarum was 2% (v / v) and the fermentation time was 4 hours.

3. The preparation method according to claim 1, characterized in that: When boiling, a single factor experiment was used to set the blanching time to 5min, 10min, 15min, 20min, and 25min respectively. Based on the sensory score as an indicator, the optimal blanching time was selected as 5min to 15min.

4. The preparation method according to claim 1, characterized in that: When seasoning, the amount of plum powder added is set to 2% (g / g), 4% (g / g), 6% (g / g), 8% (g / g), and 10% (g / g), respectively. Based on sensory evaluation as an indicator, the best amount of plum powder added is selected as 2% (g / g) to 6% (g / g).

5. The preparation method according to claim 1, characterized in that: When seasoning, a single factor experiment was used, and the pickling time was set to 15min, 30min, 45min, 60min, and 75min respectively. Based on sensory evaluation as an indicator, the best pickling time was selected as 15min to 45min.

6. A ready-to-eat leisure kelp, characterized in that: The method is prepared according to any one of claims 1 to 5.

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