JP6783016B2 - Phosphate cross-linked psyllium seed coat - Google Patents

Description

The present invention relates to phosphate crosslinked psyllium seed coats. More specifically, it relates to a psyllium seed coat in which the dietary fiber content is not significantly reduced even when the viscosity is reduced.

In recent years, the intake of dietary fiber has been decreasing due to changes in eating habits. The dietary fiber intake target amount in the Japanese dietary intake standard (2015 edition) is set to 19 g or more for adult men and 17 g or more for adult women. However, in the 2013 National Nutrition Survey, the daily dietary fiber intake for adults was 15.2 g for men and 14.3 g for women, which is not enough for the intake target amount.

The target amount of dietary fiber intake is set because there are many reports that insufficient intake of dietary fiber is associated with the development of lifestyle-related diseases. In addition, dietary fiber includes prevention of dyslipidemia, prevention of constipation, prevention of obesity, prevention of diabetes, prevention of arteriosclerosis by regulating lipid metabolism, prevention of colon cancer, synthesis of B vitamins by intestinal bacteria, and synthesis of vitamin B group in foods. It is known to have effects such as promoting the elimination of toxic substances. For this reason, incorporating dietary fiber-enriched foods into daily dietary habits is considered to be beneficial in supplementing dietary fiber, which tends to be deficient in daily diets, and maintaining and improving health.

One of the sources for ingesting dietary fiber is psyllium seed coat. Psyllium seed coat is a dietary fiber material with excellent water retention and swelling properties and a high intestinal regulation effect. Therefore, it is a food material suitable for supplementing dietary fiber that has been reported to be inadequate. On the other hand, the psyllium seed coat has a characteristic that the viscosity of the aqueous solution becomes extremely high when it is hydrated with water. Therefore, when psyllium seed coat is added to processed foods, problems such as adverse effects on processing suitability and texture may occur.

As a method for reducing the viscosity of the psyllium seed coat in order to solve this problem, a method of allowing an enzyme such as pectinase or hemicellulase to act on the psyllium seed coat is known (see Patent Document 1).

Japanese Unexamined Patent Publication No. 11-75776

However, when the viscosity of the psyllium seed coat is reduced by using these enzymes, it is considered that the dietary fiber of the psyllium seed coat is reduced in molecular weight by the action of the enzyme. Therefore, the dietary fiber content may decrease.

The present invention has been made in view of the above problems. That is, an object of the present invention is to provide a phosphate-crosslinked psyllium seed coat as a dietary fiber material to be blended in processed foods. Specifically, it is an object of the present invention to provide a psyllium seed coat having a low viscosity even when hydrated with water and having a dietary fiber content not significantly reduced.

The present invention that solves the above problems is a phosphate-crosslinked psyllium seed coat.

Psyllium seed coat contains dietary fiber consisting of polysaccharides with a highly branched structure. According to the present invention, it is considered that the structure of the polysaccharide molecule can be changed by cross-linking the constituent sugars with phosphoric acid, and as a result, the viscosity at the time of hydration can be lowered. In addition, when an acid or an enzyme is allowed to act on the psyllium seed coat, the polysaccharide contained in the psyllium seed coat is hydrolyzed to reduce the molecular weight, so that the dietary fiber content is reduced. However, when phosphate cross-linked, the polysaccharide contained in the psyllium seed coat is not decomposed, so that it is considered that the dietary fiber content does not decrease so much.

The phosphoric acid crosslinked psyllium seed coat according to the present invention has a dietary fiber content of 80% or more while having a low viscosity. Therefore, when it is blended with processed foods, it has little effect on processing suitability and texture, and it becomes easy to produce processed foods with fortified dietary fiber.

It is explanatory drawing which shows the relationship between the viscosity of the 2% solution, and the dietary fiber content in the phosphoric acid cross-linked psyllium seed coat powder and the enzyme-treated psyllium seed coat powder.

Hereinafter, suitable embodiments for carrying out the present invention will be described.

<Psyllium seed coat>
Psyllium seed coat is a dietary fiber material whose main component is a polysaccharide having a highly branched structure. Examples of the psyllium seed coat used in the present invention include a seed coat (husk) obtained from the seeds of the plantago ovata of the Plantain family, or a crushed product thereof. Here, examples of the psyllium seed coat or a pulverized product thereof include those commercially available as psyllium, psyllium husk, psyllium seed coat powder, psyllium seed gum, isagol and the like (hereinafter, referred to as "psyllium seed coat powder"). In the present invention, the psyllium seed coat powder may be of any particle size and grade, but is preferably one having a small amount of complications and a high purity.

<Phosphate cross-linking>
The phosphoric acid cross-linking treatment method in the present invention is not particularly limited, but a phosphoric acid cross-linking treatment using a phosphoric acid cross-linking agent is preferable. Phosphate cross-linking treatment conditions using a phosphoric acid cross-linking agent include the quality, degree of purification, and treatment concentration of the psyllium seed coat powder to be treated, the type and concentration of the phosphoric acid cross-linking agent used, the pH of the treatment solution, the treatment temperature, and the treatment. Appropriate conditions may be set in consideration of time and the like.

Examples of the phosphoric acid cross-linking agent that can be used in the present invention include phosphorus oxychloride, sodium trimetaphosphate, and a combination of sodium trimetaphosphate and sodium tripolyphosphate. When phosphoric acid-crosslinked psyllium seed coat powder is used for food applications, sodium trimetaphosphate that can be used as a food additive, and a combination of sodium trimetaphosphate and sodium tripolyphosphate are preferable.

The amount of the phosphoric acid cross-linking agent used for the phosphoric acid cross-linking treatment of the psyllium seed coat powder in the present invention is not particularly limited, and the pH of the treatment liquid, the treatment temperature and the treatment temperature are adjusted according to the viscosity of the target phosphoric acid cross-linking treatment psyllium seed coat powder. It can be set arbitrarily along with the processing time. For example, when sodium trimetaphosphate is used as a phosphoric acid cross-linking agent, the addition amount may be set so as to be 1% or more, preferably 2% or more with respect to the psyllium seed coat powder.

In addition, the pH, temperature, and time when the phosphoric acid cross-linking treatment of the psyllium seed coat powder in the present invention is performed can be arbitrarily set. For example, the pH of the treatment solution is preferably alkaline, specifically 9.0 or higher, preferably 10.0 or higher, and more preferably 10.5 ° C or higher. The treatment temperature is generally 30 ° C. or higher, preferably 35 ° C. or higher, and more preferably 40 ° C. or higher. The treatment time is 2 hours or more, preferably 4 hours or more, and more preferably 6 hours or more as the reaction time of phosphoric acid crosslinking.

In the phosphoric acid cross-linking treatment using the phosphoric acid cross-linking agent in the present invention, when the treatment conditions set in advance are met, an acid is added to the treatment liquid to neutralize it, and the temperature is lowered to carry out the phosphoric acid cross-linking. The process can be terminated. Examples of the type of acid used for neutralizing the treatment liquid include hydrochloric acid, sulfuric acid, phosphoric acid, and organic acids such as lactic acid and citric acid. It is also possible to proceed to the next step without performing the neutralization treatment.

The amount of psyllium seed coat powder suitable for the phosphoric acid cross-linking treatment is 0.1 part by mass to 5 parts by mass, preferably 0.3 part by mass to 2 parts by mass, more preferably with respect to 100 parts by mass of water. Is from 0.5 parts by mass to 1.5 parts by mass. When the amount of psyllium seed coat powder is 5 parts by mass or more, the viscosity of the solution during the phosphoric acid cross-linking treatment becomes extremely high and the operability deteriorates. On the other hand, when the amount of psyllium seed coat powder is 0.1 parts by mass or less, the amount of psyllium seed coat powder that can be crosslinked with phosphoric acid is small, which is disadvantageous in terms of productivity.

Examples of the method for pulverizing the phosphoric acid crosslinked psyllium seed coat include known methods such as a spray drying method, a vacuum freeze drying method, and a hydrophilic organic solvent addition method. In order to obtain a product with a high degree of purification, the water-affinity organic solvent addition method is preferable.

The hydrophilic organic solvent that can be used in the water-friendly organic solvent addition method is not particularly limited, but it is preferable to use a suitable water-friendly organic solvent according to the use of the phosphoric acid crosslinked psyllium seed coat powder of the present invention. preferable. For example, when used for applications such as foods, food additives, quasi-drugs, etc., it is preferable to use a hydrophilic organic solvent of a type and degree of purification suitable for the application. Specific examples of the water-affinity organic solvent include alcohols such as ethanol and isopropyl alcohol.

Specifically, when a water-affinitive organic solvent is added to the treatment liquid of the phosphate-crosslinked psyllium seed coat, a precipitate of the phosphate-crosslinked psyllium seed coat can be obtained. The amount of the hydrophilic organic solvent for forming a precipitate may be appropriately set so that the phosphate crosslinked psyllium seed coat is sufficiently precipitated. At this time, the effect of precipitation formation can be enhanced by adding a small amount of electrolyte and / or adjusting the pH. A powder of phosphoric acid crosslinked psyllium seed coat can be obtained by solid-liquid separation of this precipitate by a method such as centrifugation or filtration, recovery, drying, pulverization, and sieving. If necessary, salts such as a cross-linking agent that have become excessive with hydrous ethanol or the like may be washed and removed between recovery and drying.

Drying of the precipitate of the phosphoric acid crosslinked psyllium seed coat is not particularly limited as long as it can remove the solvent to a desired degree, and a suitable method may be selected from known methods. For example, methods such as heat drying, vacuum drying, freeze vacuum drying, microwave drying, and a combination thereof can be used.

The pulverization method is also not particularly limited, and any pulverization method may be used as long as the dried phosphoric acid crosslinked psyllium seed coat can be powdered. The sieving method for the pulverized phosphoric acid cross-linked psyllium seed coat powder is also not particularly limited, and any sieving method may be used if necessary. For example, a sieve or the like can be used.

Hereinafter, the present invention will be described in more detail based on Examples.

[Example 1]
15 g of psyllium seed coat powder (trade name: sterilized psyllium husk powder; Sanei Yakuhin Trading Co., Ltd.) was added to 1.4 L of water, and the pH was adjusted to 11.0-11.2 with a 2.5% sodium hydroxide aqueous solution. .. To this, 0.28 g of sodium trimetaphosphate was added as a phosphoric acid cross-linking agent, and the mixture was reacted at 45 ° C. for 8 hours while keeping the pH in the range of 11.0 to 11.2. Then, the pH was adjusted to 6.3 to 6.5 with 6N sulfuric acid to terminate the reaction. A four-fold amount of ethanol was added thereto, and the mixture was stirred for 1 hour. The obtained precipitate was recovered by centrifugation, washed with 60% ethanol, dried and pulverized to obtain phosphoric acid-crosslinked psyllium seed coat powder.

[Example 2]
The same treatment as in Example 1 was carried out except that the amount of sodium trimetaphosphate added in Example 1 was 2.82 g, to obtain phosphate crosslinked psyllium seed coat powder.

[Example 3]
The same treatment as in Example 1 was carried out except that the amount of sodium trimetaphosphate added in Example 1 was 5.64 g, to obtain phosphate crosslinked psyllium seed coat powder.

[Comparative Example 1]
To 1 L of water, 0.2 g of citric acid and 1 g of ascorbic acid were added to adjust the pH to 3.6, and 4 g of pectinase derived from the genus Aspergillus (trade name: pectinase G "Amano"; Amano enzyme) was added. To this, 50 g of psyllium seed coat powder was added and mixed, and the enzyme was allowed to act while stirring at 45 ° C. for 1.5 hours. Then, the enzyme was inactivated by heat treatment at 90 ° C. for 15 minutes, dried and pulverized to obtain an enzyme-treated psyllium seed coat powder.

[Comparative Example 2]
The same treatment as in Comparative Example 1 was carried out except that the enzyme treatment time in Comparative Example 1 was 4 hours, and an enzyme-treated psyllium seed coat powder was obtained.

[Comparative Example 3]
The same treatment as in Comparative Example 1 was carried out except that the enzyme treatment time in Comparative Example 1 was 16 hours, and an enzyme-treated psyllium seed coat powder was obtained.

The dietary fiber content and the viscosity of the 2% solution of the untreated psyllium seed coat powder and the psyllium seed coat powders obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were measured. At this time, the viscosity was measured using a B-type viscometer (25 ° C.). The dietary fiber content was measured using the enzyme-gravimetric method.

Table 1 shows the measurement results of the viscosity and dietary fiber content of the 2% solution in the phosphate-crosslinked psyllium seed coat powder and the enzyme-treated psyllium seed coat powder. In addition, FIG. 1 shows the relationship between the viscosity of the 2% solution and the dietary fiber content in the phosphate-crosslinked psyllium seed coat powder and the enzyme-treated psyllium seed coat powder.

As is clear from Table 1 and FIG. 1, the phosphate cross-linked treated psyllium seed coat powder according to the examples has a lower viscosity at the time of hydration as compared with the untreated psyllium seed coat powder, but has a dietary fiber content. It can be seen that is not so low. The cause of the decrease in the dietary fiber content of the phosphate cross-linked psyllium seed coat powder is that the ash content in the obtained phosphate cross-linked psyllium seed coat powder increased as a result of the cross-linking of phosphoric acid with the constituent sugars of the dietary fiber of the psyllium seed coat. Was thought to be.

On the other hand, the enzyme-treated psyllium seed coat powder according to the comparative example had a significantly lower dietary fiber content as the viscosity during hydration decreased as compared with the untreated psyllium seed coat powder. The degree of this decrease in dietary fiber content was much greater than that of the phosphate cross-linked psyllium seed coat powder. It is considered that the cause of the decrease in the dietary fiber content of the enzyme-treated psyllium seed coat powder is that the dietary fiber was hydrolyzed to a low molecular weight as a result of the action of the enzyme on the dietary fiber of the psyllium seed coat and was not quantified as the dietary fiber.

From the above, the phosphate crosslinked psyllium seed coat powder of the present invention is a psyllium seed coat having a low viscosity while maintaining a high dietary fiber content. When the phosphoric acid crosslinked psyllium seed coat powder according to the present invention is applied to foods and the like, the viscosity is lower than that of untreated psyllium seed coat powder, so that the processability to food is improved, which is caused by the viscosity. It is a material that has an extremely excellent effect of being useful for supplementing dietary fiber because it has less influence on the texture and has a high dietary fiber content.

Claims (2)

After the phosphoric acid cross-linking treatment, purification is performed using a water-affinity organic solvent.
Phosphate-crosslinked psyllium seed coat with a dietary fiber content of 80% or more . The phosphate-crosslinked psyllium seed coat according to claim 1, wherein the viscosity of the 2% solution is 12700 cP or less .

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