JPH09271320A - Storage of fresh lotus root - Google Patents

Abstract

PROBLEM TO BE SOLVED: To retain freshness of fresh lotus root over a long period by arbitrarily combining an organic acid with a natural antimicrobial agent and ethyl alcohol, adding the mixture to fresh lotus root and subjecting the lotus root to bacteriostatic treatment. SOLUTION: Fresh lotus root which may be lotus root having skin is brought into contact with organic acids (citric acid) and/or mustard extract and/or ethyl alcohol. Three manners each bringing fresh lotus root into contact with a mixed liquid of organic acids with mustard extract, a mixed liquid of organic acids with ethyl alcohol or a mixed liquid of organic acids with mustard extract and ethyl alcohol are preferable as method for storing the fresh lotus root.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for storing raw lotus root, and more particularly, to a raw lotus root that can retain freshness for a long period of time by bacteriostatic treatment without heat sterilization. Regarding how to save. In this specification, "raw lotus root" is dug out of soil,
The lotus root after washing with water.

[0002]

2. Description of the Related Art In recent years, as the amount of raw materials for agricultural products imported from abroad has increased, it has become an issue to transport the raw materials for agricultural products while maintaining "freshness close to rawness". Among these raw materials for agricultural products, "lotus root" is required to be distributed in a state close to raw for a long time. For that purpose, it is necessary to take measures to prevent the "lotus root" from decaying, but the cause of this lotus root decay is due to the action of microorganisms present in the lotus root.

Therefore, in order to prevent the lotus root from spoiling and maintain its freshness, it is necessary to sterilize (kill) the microorganisms. Conventionally, as a means for killing the microorganisms present in the lotus root and preventing spoilage of the lotus root, there is a method of sterilizing by heating at a high temperature of 80 ° C. or higher, but in the case of this sterilization treatment method, the protein in the lotus root is Polyphosphoric acid, alum, etc. are used as discoloration inhibitors to prevent discoloration due to microorganisms, which is caused by thermal denaturation and loses physical properties (hardness) peculiar to lotus root. There is a problem that it cannot respond to consumers' non-additive orientation. Therefore, this heat sterilization treatment cannot be said to be an effective means for preserving raw lotus root.

Therefore, in order to solve such a problem,
A bacteriostatic treatment is preferred in which the heating temperature is lowered to suppress the growth of microorganisms, rather than killing them. As this bacteriostatic treatment method, a method in which raw lotus root is sterilized by low temperature heating in a state of being immersed in an organic acid such as citric acid which is a PH-lowering agent, and a method in which raw lotus root is sterilized with a natural antibacterial agent are considered. According to the method, the growth of bacteria can be suppressed by immersing the raw lotus root in an organic acid and bringing it into contact with a natural antibacterial agent.

[0005]

However, the bacteriostatic treatment method for raw lotus root as described above has the following problems. In other words, raw lotus root has more pores than other root vegetables, so that organic acids and natural antibacterial agents used for bacteriostatic treatment penetrate quickly. In the case of the organic acid / heat sterilization treatment, the raw lotus root is soaked in the organic acid having a low PH value, so that the raw lotus root has a lot of sourness. Therefore, it is necessary to neutralize in a subsequent step, and the fiberization of raw lotus root and the like can be easily damaged by this neutralization treatment. When sterilizing with a natural antibacterial agent, the scent unique to the natural antibacterial agent remains and it is difficult to remove this scent. And other issues.

By the way, there are yeasts in addition to bacteria as microorganisms that cause decay of raw lotus root, and the organic acid and natural antibacterial agent are
A bacteriostatic effect is observed. However, in the bagged product of raw lotus root, under the condition that the pH of the organic acid is as low as 4 or less, a phenomenon in which the bagged product swells is observed although the bad odor is not generated. As a result of various studies on this cause, the present inventor has a sugar component (fiber and sugar) as a main component in the nutritional component of lotus root, and the lotus root has sugar as a sugar component of 1.5 to 5. It was found that the content was 2.0%, that fermentable yeast was proliferating with this sugar as a nutrient, and that the cause of the swelling was yeast. From this, the organic acid and the natural antibacterial agent, the bacteria in the microorganisms of the raw lotus root, the bacteriostatic effect is observed, it may not be observed sufficient yeast bacteriostatic effect I can confirm. Therefore, in order to perform good bacteriostatic treatment of raw lotus root, it is necessary to suppress the growth of bacteria in the microorganisms and the growth of yeasts.

The present inventor, based on such a problem, and as a result of further research and testing, found that the organic acid, natural antibacterial agent and ethyl alcohol were arbitrarily used for bacteriostatic treatment of raw lotus root. It was found that it is effective to use the combination.

The present invention has been made in view of the above points of view, and its object is to provide a method for preserving raw lotus root that can retain the freshness of the raw lotus by bacteriostatic treatment. It is in.

[0009]

A method for preserving raw lotus root according to claim 1 of the present invention as a means for solving the above-mentioned problems is as follows. The raw lotus root contains organic acids and / or mustard extract, and / or Alternatively, it is characterized by adding ethyl alcohol. The method for preserving raw lotus root according to claim 2 includes 0.001 to 0.05% by weight of mustard extract and / or 0.5 to 5% by volume of ethyl alcohol based on 100 parts of raw lotus root. And an aqueous solution having a pH of 5 or less with organic acids: 50 to 200 parts are added. Furthermore, the method for preserving raw lotus root according to claim 3 includes 0.001 to 0.05% by weight of mustard extract and / or 0.5 to 5% by volume of ethyl alcohol based on 100 parts of raw lotus root. And an aqueous solution having a pH of 3.0 to 4.5 with organic acids: 50 to 2
It is characterized by adding 00 parts.

Here, as the organic acids, citric acid, malic acid, tartaric acid, succinic acid and other organic acids can be used, and citric acid is usually used. The mustard extract contains a natural antibacterial agent having an action equivalent to that of allyl mustard oil extracted from black mustard seeds, horseradish roots and the like, and as the mustard extract, for example, wasa all powder Can be used. The wasaol is obtained by extracting mustard line segments from mustard and contains 10% by weight of mustard component. In addition, an aqueous solution containing 0.001 to 0.05% by weight of the mustard extract and / or 0.5 to 5% by volume of ethyl alcohol and having a pH of 3.0 to 4.5 with organic acids is used.
For 100 parts of raw lotus root, this aqueous solution: 50 parts
The reason why the configuration is such that ~ 200 parts is added is based on the test results obtained in the examples described later. When the amount of the mustard extract is less than 0.001% by weight, the bacteriostatic effect is not sufficiently exerted even in the synergistic action of the organic acids and the mustard extract, and 0.06% by weight or more. In this case, the mustard odor becomes strong and the product becomes unfavorable. Further, 0.5% by volume of the ethyl alcohol
When it is less than 6, the bacteriostatic effect is not sufficiently exerted even in the synergistic action of organic acids and ethyl alcohol, and when it is 6% by volume or more, the alcohol odor becomes strong, which is preferable as a product. Due to disappearance. In addition, if the pH is 6.0 or more due to organic acids, the bacteriostatic effect is reduced. Further, when the amount of the aqueous solution is less than 50 parts with respect to 100 parts of raw lotus root, the aqueous solution does not sufficiently penetrate into the raw lotus root, and it is difficult to obtain a good bacteriostatic effect. The reason is that the aqueous solution is wasted and no improvement in the bacteriostatic effect is observed in each stage as compared with the case of less than 200 parts.

When the raw lotus root is brought into contact with a combination of organic acids and mustard extract as a natural antibacterial agent, a good bacteriostatic effect can be obtained even against yeast. . Further, when ethyl alcohol is used in combination with organic acids and mustard extract as a natural antibacterial agent, the growth of yeast can be further suppressed. In particular, when the proper addition amount of ethyl alcohol in the immersion liquid in raw lotus root is in the range of 0.5 to 4%, the swelling phenomenon caused by the growth of yeast can be prevented. Further, when a large amount of ethyl alcohol is added to the organic acids, solid matter such as slag is observed to be generated, but when these three components are used in combination, this problem can be solved.

[0012]

As is clear from the above description, according to the method for preserving raw lotus root of claim 1 of the present invention, the raw lotus root contains organic acids and / or mustard extract, and / or
Alternatively, since ethyl alcohol is added, the treated raw lotus root can be stored for a considerable period of time without heat sterilization.

Further, according to the method for preserving raw lotus roots of claims 2 and 3, since the organic acids and / or mustard extract and / or ethyl alcohol are blended in a specific ratio, a still better quality is obtained. It has the effect of obtaining a bactericidal effect.

As described above, according to the present invention, since the characteristics of the microorganisms present in the raw lotus root are grasped and the bacteriostatic agent effective for these microorganisms is used, the conventional method for preserving the raw lotus root is Differently, there is no need to heat sterilize at 80 ℃ or higher, and lotus roots with raw physical properties can be obtained, and freshness peculiar to lotus roots that cannot be obtained by heat sterilization treatment that can meet the consumer's desire to live is retained. It has the effect of providing a method for storing lotus root.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the method for preserving raw lotus root of the present invention include the following three modes. That is, raw lotus root is contacted with a mixed solution (agent) of citric acid (organic acids) and mustard extract, raw lotus root is contacted with a mixed solution (agent) of citric acid (organic acids) and ethyl alcohol There are three forms of raw lotus root, which is brought into contact with a mixed solution (agent) of citric acid (organic acids) and mustard extract, and ethyl alcohol. However, the method for preserving raw lotus root of the present invention is not limited to this embodiment, and naturally includes a modified form without departing from the scope of the present invention. For example, add spices,
You may mix | blend a coloring agent and other additives.

Here, the raw lotus root may be either a peeled lotus root or a peeled lotus root, and may be cut to a certain thickness if necessary. Further, the organic acids are not limited to citric acid, but as described above, if they exert the same action as citric acid, malic acid, tartaric acid, lactic acid, etc.
Other organic acids may be used. The mustard extract is
It only needs to contain a substance having a natural antibacterial action containing this component, and the powder of "Mustard", the powder of "Wasabi root" or the like may be used as it is. In this case, the amount used is the amount converted into the amount of mustard extract.

In the first embodiment, 100% of raw lotus root and 100 parts of mustard extract: 0.001-
An aqueous solution containing 0.05% by weight and having a pH of 5 or less with citric acid (bacteriostatic agent): a composition in which raw lotus root is dipped at a ratio of 50 to 200 parts is preferable. When the raw lotus root in this treated state was packaged, the growth of bacteria and yeast could be suppressed. Moreover, when the raw lotus root thus treated was stored at a low temperature of 7 ° C. or lower, it could be stored for 1 week or longer. On the other hand, in the case of the conventional method in which raw lotus root was immersed only in citric acid and stored at a pH of 5 or less at low temperature, the bag was inflated in about 2 days, and the bacteriostatic effect on yeast was observed. Was not recognized.

Further, in the second embodiment, 100 parts of raw lotus root and 100 parts of lotus root are mixed with ethyl alcohol of 0.5 to 5 parts.
An aqueous solution (bacteriostatic agent) containing 50% by volume and having a pH of 5 or less with citric acid: 50 to 200 parts by weight is preferably dipped in raw lotus root. When the raw lotus root in this treated state was packaged, the growth of bacteria and yeast could be suppressed. This is because citric acid has a suppressive effect on bacterial growth and ethyl alcohol has a bacteriostatic effect on yeasts. And in this formulation,
When the content of ethyl alcohol was 2.0% by volume or more, the blistering phenomenon was not observed even after 4 days. Further, when this was stored at a cold temperature of 7 ° C., the occurrence of the blistering phenomenon could be prevented for 2 weeks or more. However, when using this bacteriostatic agent, alcohol odor is observed for the first few days.

In the third embodiment, raw lotus root: 1
For 100 parts, mustard extract: 0.001-0.05
% By weight, ethyl alcohol: an aqueous solution containing 0.5 to 5% by volume and having a pH of 5 or less with citric acid (bacteriostatic agent):
It is preferable that the raw lotus root is dipped in a proportion of 50 to 200 parts. Treatment of raw lotus root with this aqueous solution was the best, and when the treated lotus root was packed in a bag, the growth of bacteria and yeast could be suppressed. Although depending on the ratio of the aqueous solution, when this bacteriostatic agent is used, it is possible to suppress the growth of microorganisms (bacteria, yeast) in an environment of 30 ° C. or higher for 2 weeks or longer.

In each of the above embodiments, mustard extract,
Blending ratio of ethyl alcohol and P by citric acid
The above conditions for the H value are the conditions obtained from the examples described later, and in this case, a preferable bacteriostatic effect can be confirmed.
Furthermore, when this was stored at a cold temperature of 7 ° C. or lower or a low temperature heat treatment (branching treatment) of 80 ° C. or lower, a more preferable bacteriostatic effect was confirmed for 60 days or longer.

[0021]

EXAMPLES Next, in order to confirm the actions and effects of the above-described embodiments of the present invention, the bacteriostatic effect against bacteria of an aqueous solution (bacteriostatic agent) containing citric acid and mustard extract, citric acid and mustard extract Bacteriostatic effect of aqueous solution containing substances (bacteriostatic agent) on raw lotus root, bacteriostatic effect of aqueous solution containing citric acid and ethyl alcohol (bacteriostatic agent) on yeast, aqueous solution containing citric acid and ethyl alcohol (bacteriostatic agent) ) Was tested on the raw lotus root, and the bacteriostatic effect of the aqueous solution (bacteriostatic agent) containing citric acid, mustard extract and ethyl alcohol on the raw lotus root was tested. Hereinafter, each will be described.

-Test- [Bacteriostatic Effect of Citric Acid and Mustard Extract on Bacteria] First, bacteria were analyzed from raw lotus root by a conventional method [see Yoshii et al .: 421, Food Microbiology, Gihododo (1973)]. Separated. Here, the bacteria significantly remaining in the raw lotus root are
The number of viable bacteria in soil fungus (bacillus) was 105 levels per one fresh lotus root. Therefore, the isolated bacteria were inoculated into a peptone medium containing citric acid and mustard extract, and the growth state (bacteriostatic effect) of the bacteria after culturing under predetermined conditions was examined, and the results after culturing are shown in Table 1. Show.

[0023]

[Table 1]

Here, the test conditions were peptone medium as the medium, citric acid as the PH adjusting agent (organic acids),
As the mustard extract, wasaol (wasaol powder) manufactured by Midori Cross Co., Ltd. was used. This wasaol is an extract of mustard from mustard and is 10% by weight.
It contains mustard components. Therefore, 0.01% by weight of wasaol is 0.001% by weight of mustard extract, and 0.5% by weight of waosaral is 0.05% by weight of mustard extract. Table 1 shows this concentration. The culture conditions were 37 ° C and 48 hours,
The bacteriostatic effect on bacteria was determined by visually observing the degree of turbidity of the culture solution (proliferation degree of bacteria).

From these results, in the case of PH4.0, the addition amount of mustard extract was 0.05%, and in the case of PH3.5,
A good bacteriostatic effect (judgment of −) was observed in the test section in which the added amount of mustard extract was 0.01%. Further, in the test plots showing ± judgment, the growth of bacteria was very slow.
Here, when the test section showing ± judgment is set in a cold place of 7 ° C. or less, the degree of turbidity changes to + judgment after 10 days, so the storage period can be greatly extended depending on the storage conditions. It was effective. That is, it was found that citric acid has a synergistic long-term storage effect when used in combination with mustard extract in the case of low-temperature circulation of raw lotus root at 7 ° C. or lower.
In this test, citric acid was examined as a PH-lowering agent, but similar results were obtained even when acids such as lactic acid and tartaric acid were used in place of citric acid. From the above results, the mustard extract was 0.001 wt% (PH
A bacteriostatic effect was observed in the range of 3.0) to 0.05% by weight (PH 5.0).

-Test- [Bacteriostatic effect of citric acid and mustard extract on raw lotus root] Three pieces (about 7 to 7) of raw lotus root cut in a slice
10-sided) was prepared with citric acid to PH3 to PH6, and mustard extract was 0.001 wt% (wasaol 0.01 wt%) to 0.05 wt% (wasaol 0.5).
10% peptone medium (sterilized)
Added. In this case, citric acid was added to the pH adjusting agent of the medium so as to obtain a predetermined PH after sterilization. The test conditions were the same as in the above test. And
The results after culturing are shown in Table 2.

[0027]

[Table 2]

From these results, in the case of PH4.5, the addition amount of mustard extract was 0.01% by weight, in the case of PH4.0, the addition amount of mustard extract was 0.002% by weight, PH
In the case of 3.5, it was confirmed that the test section in which the amount of the mustard extract added was 0.001% by weight had the best bacteriostatic effect. Here, under the condition of pH 3.5 or less, there is a drawback that raw lotus root has a strong sourness.
In 4.5, it was confirmed that the addition amount of mustard extract was 0.002% by weight and 0.01% by weight, respectively. Further, in the test plots showing these-judgments, the temperature changed to ± judgment after 30 days under the condition of the temperature of 7 ° C or lower. In addition, the test plots showing these ± judgments show 30 when the culture temperature is set to a cold place of 7 ° C or lower.
Since the degree of turbidity is negative even after the lapse of days, a significant effect of extending the storage period by the storage conditions is recognized as in the case of the test. Also, adjust the PH to 4.5.
Even when 0.001% by weight of mustard extract was added, the bacteriostatic effect for 2 weeks or more was obtained by storing in a cold place at 7 ° C or lower. Even at normal room temperature (14-18 ° C),
A bacteriostatic effect for 1 week was obtained.

From the above results, for storage of raw lotus root, pH adjustment with citric acid was set to 5.0 or less (preferably in the range of 3.5 to 4.5), and mustard extract was adjusted to 0.
The preparation liquid added with 001 to 0.05% by weight was suitable. It was confirmed that these conditions did not spoil for about 30 days when stored in a cold place at 7 ° C or lower. Further, a preservative effect was also observed when this was subjected to a blanching treatment at 80 ° C. or lower.

-Test- [Bacteriostatic (anti-swelling) effect of citric acid and ethyl alcohol on yeasts] From a lotus root that was swollen, a conventional method [see Yoshii et al .: 455, Food Microbiology, Gihodo (1973)] The yeast was separated by. The isolated yeast is one type of yeast with strong fermentability (Saccharomyces), and the number of viable bacteria in the lotus root is 108 or more per bag in the case of bagged raw lotus root with swelling. Was given. For the determination of swelling due to the growth of yeast, the condition of gas generation in the Dalham tube in YM medium [Iizuka et al., 138, p. . The pH of the YM medium was prepared by sterilizing and adding citric acid so as to obtain a predetermined PH. After 15-minute injection into a test tube, a Dalham tube was placed, capped with a silicone stopper, and then sterilized as usual. Further, after sterilization, ethyl alcohol was added so as to have a predetermined concentration (volume%), and then 105 / ml of yeast was aseptically inoculated. The results after culturing are shown in Table 3.

[0031]

[Table 3]

Here, the test conditions were that swelling was judged by gas generation in the Dalham tube. The Dalham tube fermentation method was in accordance with [Iizuka et al., Co., P. 37, method for identifying and identifying yeast, Tokyo University Press (1969)]. The culture temperature was 28 ° C. for 4 days. The addition amount of ethyl alcohol showing a bacteriostatic effect (prevention of swelling) was 4.0% by volume in the control group in which PH adjustment was not performed. Similarly, in the test section in which the bacteriostatic effect (prevention of swelling) was observed, ethyl alcohol was 3.0% by volume in the case of PH4 to PH6, and 2.0% by volume of ethyl alcohol in the case of PH3. .

By the way, it is generally said that the growth of yeasts is vigorous even if the pH is low. In this test as well, if the addition amount of ethyl alcohol is 1% by volume or less,
It also grew under conditions as low as PH3. However, when ethyl alcohol was set to 4% by volume, no growth was observed even in the control group (test group in which PH was not prepared). From these results, it was confirmed that ethyl alcohol is effective for bacteriostatic (prevention of swelling) of yeast separated from lotus root.

-Test- [Effect of citric acid and ethyl alcohol on raw lotus root bacteriostatic (swelling prevention)] In the test, the effect of ethyl alcohol on yeast isolated from raw lotus root was confirmed. The bacteriostatic (swelling prevention) effect was examined for the substance itself. In this test method, the YM medium, ethyl alcohol concentration, and Dalham tube were sealed in a test tube and sterilized in the same manner as in the test. Then, raw lotus root (1
(Corner) was put in a test tube, capped with a silicone stopper, and cultured. The results after culturing are shown in Table 4.

[0035]

[Table 4]

The concentration of ethyl alcohol showing a bacteriostatic effect (prevention of swelling) was 2.
0% or more. By the way, in this test, the number of culture days was set to 4 days, but if the number of culture days was set to 7 days,
Ethyl alcohol is 2.0 in the test section with pH 4.0 or above.
It changed to + in% by volume. Therefore, it was found that a bacteriostatic effect of less than 7 days was obtained in this test section.

On the other hand, if the culture temperature is set to 7 ° C. or lower,
In the test section in which the amount of ethyl alcohol was 2.0%, the judgment was negative even after 2 weeks, regardless of PH. When raw lotus root is circulated at a temperature of 7 ° C. or lower at a temperature of at least 2% if the concentration of ethyl alcohol is 0.5% by volume or more.
Blisters were prevented for more than a week. Ordinary room temperature (14-
The bacteriostatic effect for 1 week was obtained even at 18 ° C. When ethyl alcohol is added at an actual factory site, it is desirable to add a preparation liquid having a concentration of at least 1% by volume or more, because ethyl alcohol easily volatilizes in the summer. On the other hand, when the amount of ethyl alcohol added is large, there is a drawback that the smell of alcohol is strong.
After 3 days, the odor of alcohol disappears and no pungent odor is felt.

Even if the amount of ethyl alcohol added was increased to 5% by volume, the alcohol odor was felt for several days.
There was no particular alcohol odor when stored for 30 days.
From the above results, PH5 or less (preferably 3.0 to
In 4.5), the amount of ethyl alcohol added is 0.5
It was confirmed that the range of up to 5% by volume was suitable. Further, the same preservation effect could be confirmed when blanching was performed at 80 ° C. or lower instead of storing in a cold place at 7 ° C. or lower.

-Test- [The mixing ratio of raw lotus root and the preparation liquid is a bacteriostatic effect] First, the preparation liquid is an aqueous solution containing PH 4.5, mustard extract 0.01% by weight, and ethyl alcohol 2.0% by volume. Mixed in. This prepared solution is sliced (major axis 5 to 5) as follows.
6 cm x minor axis 4-5 cm x thickness 5-10 cm) was mixed with lotus root. The mixture was placed in a polyethylene bag, sealed, and stored at 30 ° C. The results after culturing are shown in Table 5.
Here, the main tests were conducted on bacteria.

[0040]

[Table 5]

Here, the bacteriostatic determination was performed at 30 ° C. for 30 days, and the bacteriostatic effect was determined by visually observing the degree of turbidity of the culture solution (bacterial growth rate). In general, regarding the cause of rotting of lotus root, when the bagged raw lotus root is not subjected to heat treatment, the solid content is eluted from the lotus root into the preparation liquid by the self-digestion action of the enzyme contained in the lotus root. This eluted component serves as a nutrient source for microorganisms, and as a result,
Micro-organisms grow and are involved in decay. Further, the elution component of the solid content raises the PH of the immersion liquid, and becomes a cause of accelerating the growth of microorganisms. Therefore, in the bagging product of raw lotus root,
The form of the amount of lotus root and the mixing ratio of the preparation liquid to be dipped,
It greatly affects the amount of eluted components. In this case, with respect to the mixing ratio of raw lotus root and the preparation liquid, as the amount of the preparation liquid is relatively large, the amount of eluted components is small, and thus the increase of PH is slow and the progress of spoilage by microorganisms is slow. However, when a large amount of this preparation liquid is set, there arises a problem of commerciality such as an increase in weight of the product. On the other hand, when the mixing ratio of the preparation liquid is lowered,
Since the amount of the eluted components becomes relatively large, it is necessary to extremely lower the pH of the preparation liquid and to increase the added amounts of mustard extract and ethyl alcohol in order to increase the effect of the bacteriostatic action. .

That is, in the bag-filled raw lotus root,
The mixing ratio of the raw lotus root and the preparation liquid, the form of the lotus root, and the like are important issues for maintaining freshness after the bagging process. In the present invention, this mixing ratio is 100 parts of raw lotus root,
When 50 to 200 parts of the preparation liquid was used, turbidity did not occur even on the 30th day. In addition, the preparation liquid (bacteriostatic agent) is PH
The above was also applied to the case where 100 parts of raw lotus root and 50 parts to 200 parts of preparation liquid were used by using a mixture of 5.0, 0.001% by weight of mustard extract and 0.5% by volume of ethyl alcohol. Like the above, I was able to store it for 30 days.

From the above, the bacteriostatic method of bagged raw lotus root that retains the freshness of raw material without sterilization heat treatment is as follows: pH 5.0 or less by citric acid, mustard extract 0.001-0 0.05% by weight, ethyl alcohol 0.5
After preparing a mixed solution of ˜5% by volume and adding 50 to 200 parts of this solution to 100 parts of sliced raw lotus root, it is clear that it can be stored at 30 ° C. or higher for at least 7 to 30 days. Became. In the test,
The pH of the adjustment liquid is 4.5, but when the pH of the adjustment liquid is further lowered to 3.0, when it is stored in a cold place at 7 ° C or lower, or when blanching is performed at 80 ° C or lower. It can be stored for a long time. In the present invention, citric acid, which is an organic acid, was mainly investigated as a PH-lowering agent, but the same bacteriostatic effect could be confirmed with organic acids such as lactic acid and succinic acid.

Claims (3)

[Claims] 1. A method for preserving raw lotus root, which comprises adding organic acids and / or mustard extract and / or ethyl alcohol to raw lotus root. 2. Raw lotus root: Containing 0.001 to 0.05% by weight of mustard extract and / or 0.5 to 5% by volume of ethyl alcohol to 100 parts of raw lotus root and having a pH of 5 or less due to organic acids. Aqueous solution: A method for storing raw lotus root characterized by comprising adding 50 to 200 parts. 3. Raw lotus root: 0.001 to 0.05% by weight of mustard extract and / or 0.5 to 5% by volume of ethyl alcohol per 100 parts of raw lotus root, and PH3.0 with organic acids. ~ 4.5 aqueous solution: 50-20
A method for preserving raw lotus root which is characterized by adding 0 part.