LONG-TERM STORED SONGI MUSHROOM AND ITS METHOD FIELD OF THE INVENTION The present invention relates to a method for long-term storage of songi mushroom (scientific name: Armillaria edodes) and the songi mushrooms stored for a long time by using said method. More specifically, it relates to a method for a long-term storage of songi mushroom which comprises the steps of: putting the songi mushroom into a bag which is elastic and made of synthetic resin impermeable to water and air, degassing the bag to prevent the contact of songi mushroom with air, sealing up the bag, and preserving the bag at a temperature ranging from 10 to -40 0c; a method for a long-term storage of songi mushroom in a frozen state which comprises the steps of: putting the songi mushroom into the first bag which is elastic and made of a synthetic resin impermeable to water and air, degassing the first bag to prevent the contact of songi mushroom with air, sealing up the bag, putting the first bag into the second bag which is elastic and made of a synthetic resin impermeable to water and air, filling the second bag with water, sealing up the second bag and rapidly freezing the second bag; and the songi mushrooms preserved for a long time by using the method of the present invention.

BACKGROUND OF THE INVENTION

Songi mushroom is a high-grade natural foodstuff growing in the place where the pine trees and scrubs inhabit together and it has excellent taste and fragrance.

However, about 8 hours after its gathering, the quality of songi mushroom changes while becoming dark(the songi gatherers call this phenomenon as "sweating"), and about two-thirds of original fragrance and about one to two-thirds of the freshness are lost. After 24 hours, only about 20% of the fragrance and freshness are left.

Songi mushrooms are temporarily stored under a low temperature in a temporary storing place for a time period ranging from few days to 20 days before exportation, and, accordingly, it is unavoidable to export the songi mushrooms after its taste and fragrance are lowered.

As discussed above, no suitable method for storing songi has been developed so far and, accordingly, the price of songi varies considerably as compared with other products since it is a seasonal product capable of charging proper price only for a short period and there is a problem that the price of songi drops suddenly when the marketing time is delayed a little. Hitherto, many studies have been dedicated to develop a method for storing songi mushroom for a long time without impairing the fragrance and taste thereof, but no satisfactory method for a long-term storage of songi mushroom has been reported.

Normally grown songi mushroom has a moisture content of about 70 to 80% and yellow or pale beige color when gathered from

its habitat. It has a size of about 5 to 10 cm in its length and a unique and strong fragrance. It grows mainly in the 80% ridgeline of a high mountain and the songi mushrooms grown in the place wherein the duration of sunshine is long and fallen leaves are rare have a moisture content of about 40 to 50%. When the songi mushroom is split according to the grain, the interior of the main body is white.

With the lapse of time, the songi mushroom loses its fragrance and freshness rapidly, its color becomes dark and the surface of the mushroom becomes fragile.

In order to prevent the deterioration of songi mushroom during the storage, a method of removing moisture from the songi mushroom has been used. Further, a preservative has been also used. However, these methods have not been put to practical use because the stored mushrooms lost their natural taste and commercial value after a long-term storage.

The present inventors have endeavored for a long time to develop a method for long-term storage of songi mushroom and have developed a method which was patented as Korean Patent No. 64602.

In this patented process, a bag is put on the songi mushroom and then degassed. A prop for songi mushroom is provided in the lower part of a plastic vessel having a size capable of accommodating the songi mushroom and the mushroom is erected on the prop. A pore is formed at one side and a pressor linked by a spring to the inside of the cap is installed to press the left of the songi mushroom.

The vessel is filled up with water by flowing water through the pore and then quickly frozen for the long-term preservation of the

mushroom.

This method is advantageous in that a long-term preservation is possible, but has a problem that working efficiency is low since the working process is very inconvenient and it is very difficult to erect the songi mushroom.

The present inventors have endeavored to solve this problem and, finally, accomplished the present invention by discovering a simple method for maintaining the fragrance and freshness of songi mushroom as they are even if the mushroom is preserved for a long time.

The present inventors have discovered that the fragrance and freshness of songi mushroom can be maintained by a method comprising the steps of: putting the songi mushroom into a bag which is elastic and made of a synthetic resin sheet impermeable to water and air, such as a vinyl bag, conducting a degassing process to remove air completely, and preserving the bag in the refrigerated or frozen state at a temperature ranging from 10 to -40 oC; or a method comprising the steps of: putting the songi mushroom into the first bag which is elastic and made of a synthetic resin sheet impermeable to water and air, degassing the first bag to prevent the contact of songi mushroom with air, sealing up the bag, putting the first bag into the second bag which is elastic and made of a synthetic resin impermeable to water and air, filling the second bag with water, sealing up the second bag and rapidly freezing the second bag.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide a method for a long-term storage of songi mushroom which comprises the steps of: putting the songi mushroom into a bag, degassing the bag to remove the air completely and to prevent the contact of mushroom with air, and preserving the bag at a temperature ranging from 10 to -40°C.

It is another object of the present invention to provide a method for a long-term storage of songi mushroom in a frozen state which comprises the steps of: putting the songi mushroom into the first bag which is elastic and made of a synthetic resin impermeable to water and air, degassing the first bag to prevent the contact of songi mushroom with air, sealing up the bag, putting the first bag into the second bag which is elastic and made of a synthetic resin impermeable to water and air, filling the second bag with water, sealing up the second bag and rapidly freezing the second bag.

It is a further object of the present invention to provide the songi mushroom preserved for a long time by using the methods of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects and features of the present invention will become apparent from the following description of the invention, when taken in conjunction with the accompanying drawings, in which:

Fig. 1 shows the schematic diagram of sealed songi mushroom wherein the contact of songi mushroom with air is blocked.

Fig. 2 presents the schematic diagram of frozen songi mushroom in a plastic bag which is prepared by putting the sealed songi mushroom of Fig. 1 into a plastic bag and rapidly freezing the bag.

Fig. 3 illustrates the cross-sectional view of Fig. 2 sectioned according to line A-A.

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a songi mushroom is put into a bag, which is elastic and made of a synthetic resin impermeable to water and air, such as a vinyl bag, and the bag is degassed completely and then sealed up to prevent the permeation of air or water into the bag.

Degassing may be achieved by applying the reduced pressure to the bag, or applying pressure to the outside of the bag. The degassed bag may be sealed by using heat-melting adhesion or ultrasonic melting adhesion method, or by using an adhesive which is incompatible with water. Owing to this sealing up step, the deterioration of songi mushroom can be prevented because the proliferation of aerophilic bacteria is inhibited, and the fragrance and freshness of the songi mushroom can be maintained.

After this degassing and sealing up steps, the sealed bag is put into the second elastic bag which is impermeable to water and air, and the second bag is filled with water, sealed up and then rapidly

frozen to preserve it in a frozen state. The songi mushrooms preserved by this method is prevented from deterioration and maintain their fragrance and freshness, since the proliferation of aerophilic bacteria is prevented by degassing, and proliferation of bacteria attached to the songi mushroom is prevented and the activity of enzyme is inhibited by freezing.

Examples of the materials of the bag useful in the present invention, which is elastic and impermeable to air and water, include polyethylene sheet, polypropylene sheet, soft polyvinylchloride sheet, polyester sheet, soft cellophane sheet, and other synthetic sheets.

The songi mushrooms thus prevented from the contact with water and, thereafter, refrigerated or frozen can be preserved for a long time at a refrigerating or freezing temperature.

The present invention will be illustrated more specifically with reference to the drawings.

Fig. 1 represents a songi mushroom(1). The songi mushroom(l) is put into a bag(2), which is elastic and capable of completely blocking air, such as a vinyl bag, and the bag is degassed completely and then sealed up to blocking the contact of the songi mushroom with air. Fig. I also shows that vinyl bag(2) is completely adhered to songi mushroom(l) by putting the songi mushroom(l) into the vinyl bag(2) and then degassing the bag.

The songi mushroom prepared by putting the songi mushroom(1) into the vinyl bag(2) which is elastic and capable of completely blocking air, and then degassing the bag can be preserved at a temperature ranging from 10 to -20 %.

Further, as can be seen from Fig. 2, the songi mushroom can also be preserved by putting the songi mushroom(1) into the vinyl bag(2) which is elastic and capable of completely blocking air, degassing the bag completely, putting the bag into the plastic bag(3) which is elastic and capable of blocking the water, filling the plastic bag with water, sealing up the bag, and then rapidly freezing the bag.

Fig. 3 illustrates the cross-sectional view of Fig. 2 sectioned according to line A-A, wherein 1 represents songi mushroom; 2, a bag which is elastic and capable of completely blocking air; 3, a plastic bag which is elastic and capable of blocking the water; and 4, ice.

The following Examples are intended to further illustrate the present invention without limiting its scope.

Example 1 Soil and dust are eliminated from the gathered songi mushrooms. The mushroom was put into a vinyl bag and the bag was degassed under the reduced pressure. The degassed vinyl bag was sealed up by heat-melting adhesion or ultrasonic melting adhesion to prevent the permeation of air into the bag. The songi mushrooms thus sealed was preserved as it is in the refrigerated or frozen state at a temperature ranging from 10 to -20.

Example 2 Soil and dust are eliminated from the gathered songi mushrooms.

The mushroom was put into a vinyl bag and the bag was degassed under the reduced pressure. The degassed vinyl bag was sealed up by heat-melting adhesion or ultrasonic melting adhesion to prevent the permeation of air into the bag.

The bag was put into other vinyl bag and water was filled into the bag. The bag was sealed up and then rapidly frozen at a temperature ranging from -20 "C' to -80°(: to freeze the songi mushroom. The songi mushrooms thus frozen was preserved in the frozen state.

The songi mushrooms treated by the method of the present invention do not deteriorate and maintain its fragrance and freshness up to l year. Further, it can be preserved without deterioration up to 5 years at a temperature below zero.

While the invention has been described with respect to the above specific embodiments, it should be recognized that various modifications and changes may be made to the invention by those skilled in the art which also fall within the scope of the invention as defined by the appended claims.