JPH04316466A - Treatment of raw laver - Google Patents

Abstract

PURPOSE:To prevent the deterioration of raw laver and obtain a high-quality dried laver sheet even if a time is lapsed between the harvest and the processing of the laver and to improve the workability of the process by washing raw laver with an aqueous solution of a water-soluble salt of a specific acid. CONSTITUTION:Raw laver is washed with an aqueous solution of an acid selected from organic acids and phosphoric acids, preferably weakly acidic or weakly alkaline Na salt or K salt of citric acid, lactic acid or malic acid.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel method for treating raw seaweed. More specifically, the present invention relates to a new method for processing harvested raw seaweed to prevent the quality of seaweed from deteriorating during the period from harvesting the raw seaweed to entering the processing process for producing dried seaweed.

0002

BACKGROUND OF THE INVENTION Dried seaweed has conventionally been produced through the following process.

[0003] Harvested raw algae (raw seaweed) are removed from impurities on board a ship, washed with seawater to remove diatoms, etc., and then transported to a processing plant.

[0004] At the processing plant, depending on the amount of work, the raw algae is washed with fresh water, drained, shredded with a chopper, soaked in water, poured onto a laver with a paper machine, dehydrated, and dried. Dried seaweed.

[0005] In this process, even if you are careful about washing, soaking, etc., it is difficult to remove minute impurities, which is an obstacle to producing high-quality dried seaweed. .

[0006] Normally, raw nori obtained from one harvest is divided into several parts and processed. By the way, raw seaweed gradually deteriorates, such as turning red, so if it is processed long after it has been harvested, the quality of dried seaweed will deteriorate.

[0007] As a method to solve this problem,
No. 269473 proposes a method using inorganic acids such as hydrochloric acid and phosphoric acid, and organic acids such as acetic acid and citric acid. However, the effect is compared to when no acid is used.
Only a slight improvement in texture was observed.

[0008]

[Problems to be Solved by the Invention] Therefore, an object of the present invention is to provide a method for producing dried seaweed so that the quality of the dried seaweed does not deteriorate even when the dried seaweed is processed long after harvest. To provide a novel method for processing harvested raw seaweed, which has the advantage of preventing quality deterioration, producing stable and high-quality dried seaweed, and improving workability.

[0009]

[Means for Solving the Problems] In order to solve the above-mentioned problems in producing dried seaweed, the inventors of the present invention have conducted research and studies on improving long-term quality and workability, and have developed a water-soluble We discovered that by washing harvested raw algae (raw seaweed) with an aqueous solution of organic or inorganic acid salts, the workability was significantly improved, and the quality was also significantly improved. This led to the invention.

[0010] That is, the above purpose is to treat raw seaweed with an organic acid,
This is achieved by a method for treating raw seaweed, which is characterized by washing with an aqueous solution of a water-soluble salt of at least one acid selected from the group consisting of phosphoric acid and polymerized phosphoric acid.

[0011] In the present invention, the acid forming the salts is citric acid,
Tartaric acid, lactic acid, malic acid, phosphoric acid or polymerized phosphoric acid, and the salts are sodium salt or potassium salt. Further, the present invention is a method for treating raw seaweed using an aqueous solution of 0.005 to 0.5% by weight of the salts. Although the amount of raw seaweed (original algae) to be treated with this aqueous solution varies, it is generally treated with 0.001 to 0.15% by weight of salts based on the raw algae.

0012

[Effect] When raw algae is washed with a dilute aqueous solution of salts immediately after harvesting, impurities and diatoms attached to the raw algae can be easily peeled off.
After washing with water, a thick, shiny and clean raw algae can be obtained. For this reason, when dried seaweed is used, it is possible to obtain a high-quality product that is thick and glossy without holes or tears.

[0013] In addition, raw algae treated with the aqueous solution of salts can maintain good quality without causing red discoloration even after a long waiting time at a processing plant. For this reason, the quality of dried seaweed, which conventionally was recognized to gradually deteriorate depending on the order of processing, is stabilized by the present invention, and it becomes possible to provide high-quality dried seaweed without deterioration. Salts used in the present invention include monosodium citrate, disodium citrate, trisodium citrate, sodium acetate, sodium hydrogen tartrate, disodium tartrate, sodium lactate, monosodium malate, disodium malate, Monopotassium acid, dipotassium citrate, tripotassium citrate, potassium acetate, potassium hydrogen tartrate, dipotassium tartrate, potassium lactate,
Sodium, potassium and ammonium salts of organic acids such as monopotassium malate, dipotassium malate, ammonium citrate, ammonium lactate, monosodium phosphate, disodium phosphate, trisodium phosphate, disodium pyrophosphate, Tetrasodium pyrophosphate, monopotassium phosphate, dipotassium phosphate, tripotassium phosphate,
Examples include sodium salts, potassium salts, and ammonium salts of inorganic acids such as dipotassium pyrophosphate, tetrapotassium pyrophosphate, and diammonium phosphate, and preferably neutral, weakly acidic, or weakly alkaline salts of citric acid, lactic acid, and malic acid. Sodium salts or potassium salts. Note that sodium chloride and potassium chloride are also major components of seawater and have no effect.

[0014] These salts can be used by being dissolved in tap water, well water, etc., but it is convenient to dissolve them in seawater and sufficient effects are observed.

[0015] The amount of salt used must be adjusted depending on the time (number of times) of nori harvesting and the type of salt used.
For example, in the case of a 50% solution of sodium lactate, 200
It is used by adding and mixing 50 to 1000 ml, preferably 100 to 700 ml, per liter of water for washing. If the volume is less than 50 ml, the same effect as washing with water without adding sodium lactate aqueous solution can be obtained;
If a large amount of salt is used, exceeding 0.00 ml, the raw algae will have difficulty draining water, requiring a long time to dry, and will be heavy to hold, resulting in reduced workability.

[0016] In this method, since the salts used are almost neutral, it is necessary to take care to adjust the pH of the washing water, as disclosed in JP-A-1-269473. This is a major advantage when working at sea. Another advantage is that the liquid properties of seawater are not affected by drainage, etc.

[0017]

EXAMPLES The effects of the present invention will be explained below with reference to examples, but the present invention is not limited to the examples shown. Note that the standard grades of dried seaweed used in the Examples and Comparative Examples are shown in Tables 2 and 3 based on evaluation standards (actual results) along the coast of the Ariake Sea in Kyushu.

Example 1 Approximately 400 kg of raw algae picked at No. 5 was removed on board to remove large impurities, and then treated with treated water (pH is approximately neutral) made by adding and mixing 300 ml of sodium lactate to 100 liters of seawater. When washed, the diatoms and minute impurities were removed, resulting in a soft and glossy raw nori. When this was divided into four parts and processed according to conventional methods to make dried seaweed, a product with the black gloss characteristic of seaweed was obtained. Furthermore, there were no holes or tears in the product, and there was no loss that would normally be expected to be around 20%, and 98% of the dried seaweed was of 3rd grade quality. Furthermore, even if the order of processing was delayed, the fresh seaweed did not turn red during storage of the raw seaweed, and in the case of the fourth processed product, about 6 hours had passed before processing, but the dried seaweed did not turn red during storage. 96% of high quality dried seaweed of grade 4 was obtained. The results are shown in Table 1.

Comparative Example 1 When the same raw algae as in Example 1 was washed with water (pH approximately 2.5) using the same amount of lactic acid as in Example 1 instead of sodium lactate, raw seaweed was washed with water (pH approximately 2.5). Although it was slightly harder than No. 1, impurities were removed and the gloss was relatively good. The dried seaweed obtained by processing this raw seaweed was ranked 4th grade in the first treatment, but the quality deteriorated as the order of processing decreased in the second and third times, and in the fourth treatment, it was stored. Due to the fact that the raw seaweed inside turned red, the quality dropped to grade 6-7, resulting in dried seaweed inferior in quality compared to Example 1. In addition, holes and tears occurred in all processing processes, resulting in a total loss of more than 20%, which was a large difference when taking into account the deterioration in quality. The results are shown in Table 1.

Comparative Example 2 When the same raw seaweed as in Example 1 was washed only with seawater not containing sodium lactate, the raw seaweed was hard and had poor gloss, and the dried seaweed obtained by processing was inferior to the first treatment. Although there were some cracks and contamination with raw algae, a relatively high-quality product with a grade of 5 was obtained. However, as the order of processing goes down in the second and third processing, the quality deteriorates, and in the fourth processing, Due to the fact that the raw nori turned red during storage, the quality of the dried nori was extremely poor, ranking 7-8. Note that the elapsed time until the fourth processing was about 6 hours. Moreover, holes and tears occurred in all the processing processes, resulting in a loss of nearly 30% of the total, and when combined with the reduction in quality, more than 40% of the products were rejected. The results are shown in Table 1.

Example 2 The same raw algae as in Example 1 were used, and the same treatment as in Example 1 was carried out except that sodium malate was used instead of sodium lactate. As a result, the same quality as in Example 1 was obtained. We were able to obtain dried seaweed (Top 4 in the first treatment, Top 5 in the fourth). The results are shown in Table 1.

Example 3 The same raw algae as in Example 1 were used, and the same treatment as in Example 1 was carried out except that a mixture of equal amounts of trisodium citrate and monopotassium citrate was used instead of sodium lactate. As a result, as in Example 1, good quality dried seaweed (3rd grade in the first treatment, top 5 in the fourth treatment) could be obtained. The results are shown in Table 1.

Example 4 The same raw algae as in Example 1 were used, and the same treatment as in Example 1 was carried out except that potassium tartrate was used instead of sodium lactate. As a result, sodium lactate was used in raw nori. Although the gloss was slightly inferior compared to the case, the processing went well and good quality dried seaweed was obtained (Top 4 in the first treatment, Top 5 in the fourth). The results are shown in Table 1.

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

[Table 3]

[0027]

[Effect of the invention] By treating raw seaweed with water-soluble salts, it does not turn red even after harvesting, improving workability during production, and reducing the gradual deterioration that was previously possible depending on the order of processing. The recognized quality of dried seaweed is stabilized by the present invention, and homogeneous and high-quality dried seaweed can be obtained without deterioration.

Claims (4)

[Claims] 1. A method for treating raw seaweed, which comprises washing raw seaweed with an aqueous solution of a water-soluble salt of at least one acid selected from the group consisting of organic acids and phosphoric acid. 2. The method for treating raw nori according to claim 1, wherein the acid forming the salts is citric acid, tartaric acid, lactic acid, malic acid, phosphoric acid or polymerized phosphoric acid. 3. The method for treating raw seaweed according to claim 1 or 2, wherein the salts are sodium salts or potassium salts. 4. The method for treating raw seaweed according to any one of claims 1 to 3, wherein an aqueous solution of 0.005 to 0.5% by weight of the salts is used.