JP7621685B2 - Rice paper containing seaweed and its manufacturing method - Google Patents

Description

The present invention relates to a method for producing rice paper with added seaweed and the rice paper with added seaweed produced by said method.

Lover (Porphyra tenera) is a type of red algae belonging to the Bangiceae family and is one of Korea's representative seaweeds. Laver is a type of seaweed that is mainly cultivated on the southwest coast and is mainly exported to the United States, China, Japan, and Southeast Asia.

Nori is produced in coastal farms using pole and floating methods, with Nori seedlings attached to cultivation nets called Nori nets from late September to mid-October. During cultivation, sulfate ions from the seawater combine with components of the Nori to produce sulfur polysaccharides, which are known to have excellent physiological functions. A representative polysaccharide found in Nori is porphyran, which is a water-soluble acidic polysaccharide that facilitates intestinal activity, improves intestinal flora, lowers blood cholesterol, and has anti-cancer and anti-inflammatory effects, and is attracting attention as a functional material.

It is rich in nutrients, minerals and amino acids, and has a unique flavor, making it a popular food, and it has also attracted attention overseas as a low-calorie healthy snack. However, while the production of nori has increased due to recent developments in cultivation technology, processed foods using nori are limited to dried nori, which is baked using heat, seasoned foods (including snacks), and nori tempura. Therefore, it is time to develop various processing methods to increase the utilization of nori, which is currently limited to simple processed foods.

Rice paper, on the other hand, is a food made by rolling out rice flour thinly and drying it. It is a popular staple food in Vietnam, and in Korea, it is served as a type of ssam (a wrapped food) with shabu-shabu. Rice paper is made in the form of a very thin sheet of paper, which can be rolled up with ingredients placed on it, making it easy to eat. Specific examples include Vietnamese fresh spring rolls, fresh spring roll wrappers, deep-fried spring rolls, dim sum, spring rolls, and dumpling wrappers.

The inventors therefore carried out research to develop a new processed food using seaweed, and as a result, they discovered that rice paper made in the form of rice paper and containing added seaweed can not only be used in a variety of dishes, but also has high protein content and antioxidant effects, satisfying the needs of health-conscious consumers, and thus completed the present invention.

The object of the present invention is to provide a method for producing rice paper with added seaweed.
Another object of the present invention is to provide rice paper with added seaweed.

In order to achieve the above objectives,
The present invention comprises the steps of mixing seaweed, tapioca starch, rice flour, salt and water to form a dough (step 1);
The method for producing rice paper with added seaweed includes the steps of steaming the dough (Step 2); and drying the steamed dough (Step 3).

The present invention also provides rice paper containing added seaweed produced by the above method.

The method for producing rice paper containing added seaweed according to the present invention makes it possible to provide rice paper that has excellent flavor, texture, antioxidant activity and nutritional value, and can be used in a variety of dishes.

FIG. 1 shows a manufacturing process diagram of rice paper using a powder of rubber (LRP) according to the present invention. 1 is a graph showing the results of a sensory evaluation of rice paper containing nori seaweed (LRP) according to the present invention and a positive control rice paper. 1 is a graph showing the results of analyzing the ABTS radical scavenging ability of rice paper containing laver according to the present invention (LRP) and positive control rice paper. 1 is a graph showing the results of analyzing the total phenolic compound content of rice paper containing laver (LRP) according to the present invention and positive control rice paper.

The present invention is described in detail below.

[Method of manufacturing rice paper with added seaweed]
The present invention comprises the steps of mixing seaweed, tapioca starch, rice flour, salt and water to form a dough (step 1);
steaming the dough (Step 2); and drying the steamed dough (Step 3).

In the manufacturing method according to the present invention, commercially available dried or dehydrated seaweed can be used as the seaweed, and the seaweed may be crushed and used in the form of shredded seaweed (or powdered seaweed). In this case, the method for drying and crushing the seaweed can utilize any process generally used for drying and crushing seaweed.

In the manufacturing method according to the present invention, the seaweed, tapioca starch, rice flour and salt in step 1 may be mixed in a weight ratio of 2:4-8:1-3:0.01-0.5, and preferably, the seaweed, tapioca starch, rice flour and salt may be mixed in a weight ratio of 2.0:5.5-6.5:1.5-2.5:0.05-0.15. The above mixing ratio is a ratio for providing the taste and nutritional value of the rice paper with added seaweed in an optimal state, and in order to prevent the rice paper from cracking or breaking and to improve the texture, it is preferable to mix the materials to fit the above ratio range.

In the manufacturing method according to the present invention, the water in step 1 may be mixed in an amount of 4 to 10 times the volume of the tapioca starch, preferably 4 to 6 times the volume of the tapioca starch. If less water is mixed than the above range, the ingredients will not bond and mix well, making it difficult to form the rice paper dough, and if more water is mixed than the above range, problems such as the rice paper breaking may occur.

In the manufacturing method according to the present invention, the dough in step 2 may be rolled out to a diameter of 12-18 cm and a thickness of 0.1-5.0 mm, and preferably rolled out to a diameter of 14-16 cm and a thickness of 0.5-3.0 mm, and steamed. When formed into the above size and thickness ranges and steamed, the rice paper can be provided with the fluidity to encase the filling, and the rice paper can be used as a variety of filling materials.

In the manufacturing method according to the present invention, the steaming in step 2 may be performed at 95 to 120°C for 10 to 300 seconds. Preferably, the steaming may be performed at 95 to 110°C for 10 to 60 seconds. If the steaming is performed at a temperature lower than the above range and for a short time, the cohesive strength, texture, and taste of the paper may decrease, and if the steaming is performed at a temperature higher than the above range and for a long time, the moisture may evaporate excessively, making the rice paper hard and resulting in a poor texture and causing the rice paper itself to crack.

In the manufacturing method according to the present invention, the drying in step 3 can be carried out at 30-40°C for 10-48 hours, preferably at 32-38°C for 20-30 hours. If the drying is performed at a temperature lower than the above range and for a short time, the cohesive strength of the paper will decrease and it will take a long time to dry, whereas if the drying is performed at a temperature higher than the above range and for a long time, water will evaporate excessively, making the rice paper hard and resulting in a poor texture and the rice paper itself may crack.

[Rice paper with added seaweed]
The present invention further comprises the steps of: mixing the seaweed, tapioca starch, rice flour, salt and water to form a dough (Step 1);
The present invention provides a method for producing rice paper containing added nori seaweed, the method comprising the steps of steaming the dough (Step 2); and drying the dough (Step 3).

Rice paper with added seaweed according to the present invention may have antioxidant activity. Rice paper with added seaweed according to one embodiment of the present invention has improved sensory properties, antioxidant activity, protein content and nutritional value compared to rice paper without added seaweed (see Examples 2-5).

The present invention will be described in more detail with reference to the following examples. However, the following examples are merely intended to embody the content of the present invention and are not intended to limit the present invention.

Example 1: Production of rice paper containing added seaweed Dried seaweed was purchased commercially and crushed and ground finely before use to add to the rice paper.

First, tapioca starch, rice flour, laver powder, salt, and water were mixed as shown in Table 1 below to produce rice paper dough. At this time, the tapioca starch, rice flour, laver powder, and salt were mixed in a weight ratio of 6:2:2:0.1, and the water was mixed in a volume 5 times the weight of the tapioca starch.

The mixed rice paper dough was spread thinly in a steam cylinder with a diameter of 15 cm and steamed for 30 seconds. The steamed rice paper was spread in a dryer and dried at 35°C for 24 hours to remove moisture, and finally, rice paper using a powder of rubber (LRP) was produced. The manufacturing process of the rice paper with added seaweed is shown in Figure 1.

Preparation Example 1: Preparation of rice paper without added seaweed In order to compare and analyze the nutritional value of rice paper with added seaweed and rice paper currently on the market, three types of rice paper were purchased and used as positive controls 1, 2, and 3: rice paper manufactured by P company (S rice paper product; tapioca starch 68%, rice flour 30%, etc.), rice paper manufactured by A company (M square spring roll wrapper product; tapioca starch 56.9%, rice flour 32.5%, etc.), and rice paper manufactured by M company (M round spring roll wrapper product: tapioca starch 56.9%, rice flour 32.5%, etc.).

Example 2: Analysis of general component composition of rice paper The general components of the rice paper containing added seaweed (LRP) and the positive control rice papers 1 to 3 were analyzed.

The analysis and measurement of general components (moisture, carbohydrates, crude fat, crude protein, ash) was performed according to the test method of the Food and Drug Safety Agency's Food Revolution (2020). The moisture content was measured using the normal pressure heating drying method, which involved drying in a dry oven at 105°C for 5 hours. The crude fat content was measured using the Soxhlet method with petroleum ether as the extraction solvent. The crude protein content was measured using the semi-Kjeldahl method, in which a proteolytic agent and sulfuric acid were added to the sample to decompose it, and the content was measured using an automatic protein analyzer. The ash content was measured using the direct ashing method at 550-600°C until white or grayish-white ash was obtained. The carbohydrate content was calculated as the remaining value after subtracting the moisture, crude fat, crude protein, and ash contents in 100g of sample, and the analysis results are shown in Table 2 below.

The analysis showed that carbohydrates were the highest in all samples, and the rice paper with added seaweed (LRP) showed higher crude protein than the positive control. These results confirmed that the addition of seaweed increased the solids content.

Example 3: Sensory evaluation of rice paper A sensory evaluation was performed on the rice paper containing added seaweed (LRP) and the rice papers of positive controls 1 to 3. A panel of 20 educated members was selected to carry out the sensory test. Before carrying out the test, the panel members were given sufficient explanations and training to ensure that they were fully aware of each item. The samples for the sensory test were placed in water at 80°C for 30 seconds and then served in a bowl for the sensory test. The evaluation items were appearance, color, taste, texture, and overall acceptability, and were evaluated on a 5-point scale. The results of the sensory evaluation are shown in FIG. 2.

As shown in Figure 2, the appearance, color, and overall liking of the LRP were evaluated at the same level as the positive control, and in particular, the LRP was shown to have much higher scores for aroma and texture upon ingestion than the positive control. Therefore, it was confirmed that the rice paper containing added seaweed produced according to the present invention has sufficient palatability and is commercially viable.

Example 4: Evaluation of antioxidant activity of rice paper
4-1. Production of rice paper extract
To measure the antioxidant activity of the rice paper containing added seaweed (LRP) and the rice papers of positive controls 1 to 3, each sample was subjected to solvent extraction with 94% ethanol aqueous solution to produce an extract. Specifically, the rice paper sample was added to a 94% ethanol aqueous solution with a volume 10 times the weight of each sample, and the rice paper sample was stirred and extracted at 40°C and 150 rpm for 3 hours. The extract solution was filtered, concentrated, and the solvent was removed to obtain a rice paper extract. Each of the obtained extracts was diluted with ethanol to a concentration of 200 mg/mL and used in the experiments.

4-2. Evaluation of ABTS radical scavenging ability <br/> The ABTS radical scavenging ability was confirmed for rice paper containing added seaweed (LRP) and the positive control rice papers 1 to 3.

A 7 mM ABTS solution containing 2.4 mM potassium persulfate was prepared and stored in a dark room for 16 hours. This solution was diluted to 0.700 ± 0.005 at 734 nm before use. 150 μL of ABTS solution and 50 μL of the rice paper extract sample prepared in 5-1 above were poured into the solution, and the solution was left in the dark for 6 minutes. The absorbance was measured at 743 nm, and the ABTS radical scavenging ability (ABTS radical-scavenging, %) was calculated.

As shown in Figure 3, the ABTS radical scavenging activity of LRP was shown to be much higher than that of the positive control, and activity was similar to that of 5 mM trolox as a standard antioxidant. These results confirmed that the antioxidant activity of rice paper (LRP) with added seaweed was excellent.

4-3. Evaluation of total phenolic compound content <br/> The total phenolic compound content was analyzed for rice paper with added seaweed (LRP) and rice paper positive controls 1 to 3. In general, polyphenol compounds are one of the secondary metabolites widely distributed in plants, and phenolic compounds with various structures and molecular weights have physiological functions such as antioxidant, antibacterial, and anticancer properties due to the phenolic hydroxyl (OH) group binding to macromolecules such as proteins, and are known to be contained in large amounts in green tea in particular.

To examine the antioxidant activity of rice paper, 200 μL of the extract was mixed with 100 μL of 1N Folin-Ciocalteu's reagent, left for 3 minutes, and then mixed with 300 μL of 10% Na ₂ CO ₃ solution to analyze the total phenolic compound content. After leaving for 1 hour, the absorbance was measured at 765 nm. The total phenolic compound content (total phenol, mg GAE/g) was measured by substituting it into the standard curve of gallic acid, a standard substance.
As shown in FIG. 4, the total phenolic compound content of LRP was shown to be higher than that of positive controls 1 to 3.

Example 5: Analysis of Amino Acid Composition of Rice Paper Amino acid analysis was conducted at the Gangneung Wonju University Joint Experimental Training Center.

5-1. Analysis of amino acids <br/> The amino acid content of rice paper containing added seaweed (LRP) and positive control rice paper 1 to 3 was analyzed.

About 50 mg of each rice paper sample was placed in a digestion bottle, 40 mL of 6N HCl was added, nitrogen gas was injected, the bottle was sealed, and hydrolysis was performed at 110°C for 24 hours. The hydrochloric acid was concentrated under reduced pressure at 50°C, diluted with 50 mL of 0.2N sodium citrate buffer (pH 2.2), and filtered using filter paper (0.45 μm, Pall Life Sciences, California, USA). The filtered samples were analyzed for composition and content using an amino acid analyzer (L-8900 High-speed Amino Acid Analyzer, Hitachi, Tokyo, Japan), and the results are shown in Table 3 below.

As shown in Table 3 above, the constituent amino acids of LRP were analyzed with the highest concentration of Ala (alanine) at 7.800 mg/g, followed by Glu at 5.665 mg/g, Asp (aspartic acid) at 5.382 mg/g, and Leu (leucine) at 4.210 mg/g.

5-2. Analysis of free amino acids <br/> The free amino acid content of rice paper containing added seaweed (LRP) and the positive control rice papers 1 to 3 was analyzed.
Free amino acid analysis was performed using a high-speed amino acid analyzer (LA8080; Hitachi Co., Tokyo, Japan). Approximately 5 g of sample was collected, 30 mL of 6N HCl was added, and hydrolysis was performed at 130° C. for 24 hours. 50 mL of distilled water for analysis was added to the decomposed sample, and the solution was filtered through a 0.22 μm nitrocellulose filter, after which 20 μL was injected for analysis.

As shown in Table 4 above, the free amino acid analysis of LRP showed the highest concentration of Ala (alanine) at 25,568.656 mg/100 g, followed by Tau (taurine) at 24,336.792 mg/100 g, Glu (glutamic acid) at 17,756.150 mg, and Arg (arginine) at 747.926 mg/100 g.

So far, the present invention has been described with a focus on its preferred embodiments. Those skilled in the art will understand that the present invention can be embodied in modified forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered in an illustrative rather than restrictive sense. The scope of the present invention is set forth in the claims, not in the foregoing description, and all differences within the scope of the equivalents thereto should be construed as being included in the present invention.

Claims (5)

mixing seaweed, tapioca starch, rice flour, salt and water to form a dough (Step 1);
The method for producing rice paper with added seaweed includes the steps of steaming the dough (Step 2); and drying the steamed dough (Step 3 ).
The method of the step 1, wherein the laver, tapioca starch, rice flour and salt are mixed in a weight ratio of 2:4-8:1-3:0.01-0.5. The method of claim 1, wherein the water in step 1 is mixed in an amount 4 to 10 times the volume of the tapioca starch. The method of claim 1, wherein the dough in step 2 is stretched to a diameter of 12-18 cm and a thickness of 0.1-5.0 mm and steamed. The method of claim 1, wherein the steaming in step 2 is carried out at 95 to 120°C for 10 to 300 seconds. The method of claim 1, wherein the drying in step 3 is performed at 30 to 40°C for 10 to 48 hours.