JP2002233344A - Disinfecting method using chlorine dioxide agent with ultrasonic irradiation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disinfecting method for a food. SOLUTION: This disinfecting method comprises irradiating ultrasonic waves to an object to be disinfected in the presence of a chlorine dioxide agent containing chlorine dioxide, or irradiating ultrasonic waves to an object to be disinfected followed by contacting the resultant product to a chlorine dioxide agent containing chlorine dioxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disinfection method using a chlorine dioxide agent and ultrasonic irradiation in combination,
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disinfection method mainly suitable for disinfecting foods and enhancing the disinfection effect of a chlorine dioxide agent by ultrasonic irradiation.
In addition, in this specification, "sanitization" means "sterilization",
It also includes concepts such as "sterilization" and "disinfection".

[0002]

2. Description of the Related Art Hemorrhagic Escherichia coli 0-157 which has been violent in Japan and has shook the Japanese people for 1996 to 10 years.
Are serious problems due to food poisoning caused by S. aureus and entropotoxin poisoning caused by Staphylococcus aureus which caused more than 15,000 food poisoning patients in 2000. In addition, about 40,000 food poisonings are reported each year in Japan, and most of them are said to be caused by Salmonella. This, in turn, suggests that under current hygiene practices in Japan, food poisoning cannot be completely suppressed. Administrative authorities have also issued guidelines, for example, that Salmonella and fecal coliforms should not be detected in chicken.

[0003] However, the current sterilization method has its own limitations. For example, vegetables, fruits, seafood or meat storage, for example, chicken, beef, pork, horse meat and other food products to remove bacteria, hypochlorous acid, sodium hypochlorite, hydrogen peroxide and the like have been conventionally used. However, the effectiveness of these drugs has been questioned and serious toxicities, such as trihalomethane, by-produced by these drugs, are of concern.

[0004] Furthermore, there are serious defects in the germicidal ability of these drugs and the stability of the drugs. In consideration of these circumstances, as a disinfectant, oxygen scavenger, ethanol vapor generator,
Attempts have been made to use ethylene adsorption / decomposition agents. However, it is known that the effect of the oxygen absorber depends on the water content and has no effect on the growth suppression of anaerobic bacteria. Ethanol vapor generators have a problem in terms of the effectiveness of sterilization because they do not show any sterilization effect unless the concentration is high.

[0005]

In consideration of these points, it has been studied to use ultrasonic waves in addition to the disinfectant. The combined use of a disinfectant and an ultrasonic wave is described in, for example,
No. 133,865. In this publication,
Although ultrasonic waves and ozone are used in combination, it is difficult to maintain a specified amount of ozone in the cleaning liquid by cavitation. Further, Japanese Patent Application Laid-Open No. 2000-116313 discloses a cleaning method of ultrasonically cleaning a broiler using alkaline water and acidic ionized water. But,
The disinfection ability of alkaline water and acidic ion water is inherently weak, and its effect is problematic. Further, Japanese Unexamined Patent Application Publication No. 10-11
No. 7,948 discloses a method of transmitting ultrasonic vibrations and removing bacteria by irradiating ultraviolet rays.
However, the eradication by this method is an eradication of only the surface of the eradication target, and it is impossible to expect the eradication at a deep part of the eradication target.

[0006] The present invention has been made in view of these circumstances, and an object of the present invention is to provide a method for disinfecting foods and the like having a high disinfecting effect.

[0007]

According to the present invention, there is provided a method for disinfecting a bacterium using a chlorine dioxide agent and ultrasonic irradiation in combination, comprising the steps of removing a bacterium in the presence of a chlorine dioxide agent containing a chlorine dioxide generator that generates chlorine dioxide. It is characterized by irradiating the object with ultrasonic waves.

[0008] Further, the disinfection method of the present invention using a chlorine dioxide agent and ultrasonic irradiation together comprises a step of irradiating an object to be disinfected with ultrasonic waves and a step of contacting the object with a chlorine dioxide agent generating chlorine dioxide. It is characterized by including.

In general, microorganisms adhering to or surviving on food materials and the like rarely inhabit food materials as single cells, and form colonies and clumps, and further, clumped cells. In many cases, the entire colony is covered and protected with a protein or a viscous polysaccharide substance produced by the microorganism itself. Therefore, simply immersing a food material in a disinfectant has a limit in its disinfecting effect. In the method of the present invention, the protected colonies and agglomerates are destroyed by ultrasonic waves, and a chlorine dioxide agent is brought into contact with the destroyed colonies and agglomerates to enhance the disinfection effect.

[0010] In food materials and the like, microorganisms are
For example, it may inhabit the pores of the surface of the food material such as pores of chicken skin, but in the method of the present invention, even for microorganisms that inhabit the pores of the food material by irradiation of ultrasonic waves,
It is possible to enhance the disinfection effect by contacting a chlorine dioxide agent.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The term "chlorine dioxide agent" as used herein means a substance containing chlorine dioxide, for example, chlorite such as sodium chlorite, potassium chlorite, etc.
It can be generated by adding an inorganic acid such as hydrochloric acid or sulfuric acid. Chlorine dioxide can also be generated from a chlorine dioxide generator.

Further, the chlorine dioxide may be generated from a stabilized chlorine dioxide agent in which chlorite is stabilized by a stabilizer. Here, as a stabilizer, 2Na ₂ C
_{O 3 · 3H 2 O 2,} NaHCO 3, can be exemplified NaBO ₃ or the like. Such a stabilized chlorine dioxide agent is provided as BIOTALK or BIOSUKEGAWA by Sukekawa Chemical Co., Ltd.

Further, the chlorine dioxide is obtained by generating the chlorine dioxide agent from a chlorine dioxide agent activated to generate chlorine dioxide by an activator selected from organic acids, mineral acids, hydrogen peroxide and alcohols. You may. here,
As the organic acids, for example, citric acid can be mentioned as a representative example, and as the mineral acids, for example,
Sulfuric acid can be mentioned as a representative example. Further, as the alcohols, for example, ethanol can be mentioned as a typical example. Such activated chlorine dioxide agent is available from Sukekawa Chemical Co., Ltd. under BIOSUKEGAWA design No.
Offered as 1,000.

In the method of the present invention, the preferred concentration of chlorine dioxide is 0.5 to 500 ppm, more preferably 1 to 50 ppm, still more preferably 30 to 50 ppm.
pm. When the concentration of chlorine dioxide is lower than the above lower limit, it is not preferable because the bactericidal power is lowered. On the other hand, when the concentration of chlorine dioxide is higher than the above upper limit, the bleaching action due to strong oxidizing power becomes remarkable, which is not preferable.

The above-mentioned chlorine dioxide agent has a concentration of 10 to 100 times less than that of sodium hypochlorite which has been conventionally used in a short period of time, and has a wider disinfection area. Compared with sodium hypochlorite, it reacts with organic substances in water to produce trihalomethane, which is a carcinogen, by-product, and is non-specifically reacted with organic substances in water like sodium hypochlorite for consumption. Never. Therefore, the concentration in water is kept constant for a long time, and its stability is excellent, which is suitable for long-time continuous eradication. Further, the disinfecting activity is not affected by the pH unlike sodium hypochlorite.

The mechanism of action of the bacterium elimination of the chlorine dioxide agent is to exhibit the bactericidal action by the oxidation reaction of chlorine dioxide.
Chlorine dioxide in contact with microorganisms is first decomposed into hypochlorite ions and nascent oxygen, and the resulting hypochlorite ions are also decomposed into nascent oxygen. Microbial cells are surely destroyed and killed by the nascent oxygen generated by these two molecules.

In addition, chlorine dioxide does not react with unsaturated fatty acids such as aliphatic amines, polysaccharides, maleic acid and fumaric acid, and therefore, does not cause any damage to vegetables and fruits composed of natural sugars. In addition, deactivation due to consumption of chlorine dioxide is reduced, and the activity is maintained for a long time. In addition, chlorine dioxide can exhibit a disinfecting activity in a wide pH range, and its application range is naturally widened. In terms of toxicity, the toxicity of sodium hypochlorite is 12 mg / kg for LD50 by oral administration to mice, whereas the toxicity of chlorine dioxide is LD50 by oral administration to mice of 3.6 to 3.
8 g / kg, 1/30 of the toxicity of sodium hypochlorite
0 or less. Also, it is said that dermatitis develops if sodium hypochlorite is used regularly, but with chlorine dioxide, irritation is not observed even for cumulative application, and a 210 ppm aqueous solution is dropped into the eyes of guinea pigs. Also reported no irritation.

In the method of the present invention, when the surface of the object to be disinfected has water repellency, the hydrophobic surface is made hydrophilic to improve the contact with the chlorine dioxide agent. It is preferable to add a hydrophilizing agent such as an alcohol or a surfactant and perform ultrasonic irradiation. Examples of the alcohol include many alcohols represented by ethanol, and examples of the surfactant include sorbitan fatty acid esters such as sorbitan monolaurate.

The object to be disinfected in the present invention is mainly
Food products such as meat, fish and shellfish, vegetables, fruits, etc., and food processing base materials such as food materials for prepared foods, food materials for fresh confectionery, and materials for retort food products obtained from these food products.

The preferred frequency of the ultrasonic wave applied in the method of the present invention is 5 to 150 kHz, and 50 to 80 kHz.
z is more preferred. The frequency of the ultrasonic wave may be appropriately selected according to the object to be sterilized. For example, a low frequency may be used for soft food such as salmon roe and cod, and a high frequency may be used for food having a firm tissue.

The preferred temperature at the time of ultrasonic irradiation in the present invention is 1 to 40 ° C., preferably 15 to 25 ° C. The preferable irradiation time of the ultrasonic wave is 1 to 30 minutes, more preferably 5 to 10 minutes.

In the present invention, the step of bringing the object to be sterilized into contact with a chlorine dioxide agent and the step of irradiating ultrasonic waves do not necessarily need to be performed at the same time. Even if the contacting step is a subsequent step, there is no difference in the effectiveness of the eradication.

[0023]

EXAMPLES <Preparation of Chlorine Dioxide Agent A> As an activated chlorine dioxide agent, one prepared by diluting BIOSUKEGAWA design No. 1000 (manufactured by Sukekawa Chemical Co., Ltd.) to adjust the chlorine dioxide concentration to 50 ppm was used. As activators, 0.25% by weight of commercially available sorbitan monostearate and 0.01% by weight of sorbitan monolaurate were added. This was designated as chlorine dioxide agent A.

<Examples 1 to 6, Comparative Examples 1 to 12> The bactericidal effect of the above chlorine dioxide agent A and ultrasonic irradiation on various vegetables and fruits (specimens) was examined. The results are shown in Table 1. In the test shown in Table 1, the specimens shown in Table 1 were immersed in chlorine dioxide agent A, and ultrasonic waves (50 kHz) were applied at room temperature for 5 minutes.
And then left at room temperature for 15 minutes. Then, the sample was neutralized with a sterilized 0.1% sodium thiosulfate solution, and 1.0 g to 5.0 g of the sample was accurately collected and homogenized with a stomacher for 2 minutes as usual to obtain a sample. Microorganisms of this sample were detected in accordance with the Sanitary Test.

[0025]

[Table 1]

Comparative Examples 1, 3, 5, 7, 9 and 11 (control) were immersed in 300 ml of sterile purified water for 10 minutes, while Comparative Examples 2, 4, 6, 8, 10 and 12 were 30
This was immersed in 0 ml of chlorine dioxide agent A for 10 minutes. In Examples 1 to 6, an object was added to 500 ml of chlorine dioxide, and an ultrasonic wave generator (volvoclear, 5
0 kHz) for 10 minutes while maintaining the temperature at 25 to 35 ° C. Although there is some variation in the eradication rate of microorganisms depending on the sample, 50 ppm of chlorine dioxide
In Comparative Examples 2, 4, 6, 8, 10 and 12 immersed in chlorine dioxide A containing chlorine for 10 minutes and not irradiated with ultrasonic waves, the results were compared with the control (Comparative Examples 1, 3, 5, 7, 9 and 11). The number of general bacteria is reduced to about 1/10 (the eradication rate is 90%)
In Examples 1 to 6 using ultrasonic irradiation in combination, the number of general bacteria was 1/100 to 1/1000 (the eradication rate was 99 to 99.9%).
Significantly reduced. Similarly, it was confirmed that 100% of the coliform bacteria were removed by the combined use of a chlorine dioxide agent and ultrasonic irradiation.

<Example 7, Comparative Examples 13 to 15> Table 2 shows the results of examining the bactericidal effect of the chlorine dioxide agent A and ultrasonic irradiation on chicken eggs. By immersion in chlorine dioxide A containing 50 ppm of chlorine dioxide for 5 minutes at room temperature, the number of common bacteria was removed by 97.3% (Comparative Example 15). 99.9
A surprising eradication rate of 5% has been observed (Example 7). On the other hand, Staphylococcus aureus was found to survive even when immersed in chlorine dioxide agent A at room temperature for 5 minutes (Comparative Example 15), but was compared with chlorine dioxide agent A and ultrasonic waves (50 kHz) at room temperature for 5 minutes. Staphylococcus aureus was completely removed by the combined treatment (Example 7).

[0028]

[Table 2]

<Example 8, Comparative Examples 16 to 21> The germicidal effects of chlorine dioxide agent A and ultrasonic irradiation (50 kHz) on salmon roe, scallops, and mentaiko as seafood base materials were examined. Table 3 shows the results.

[0030] Ikra was placed in sterile phosphate buffered saline for 2 hours.
When suspended for 0 minutes, the general bacterial count is 6.9 × 10 ⁷ C
Although FU / g (wet body) was detected (Comparative Example 16), immersion in chlorine dioxide agent A for 10 minutes resulted in 9.4 × 10 ⁴ CFU.
/ G (wet body), and the removal rate was 99.9% (Comparative Example 17). No common bacteria were detected at all by the combined use of the chlorine dioxide agent A and ultrasonic irradiation (50 kHz) at room temperature for 10 minutes, and the bacteria were completely eliminated (Example 8).

In the case of scallop, chlorine dioxide agent A and room temperature 10
The number of general bacteria can be reduced to about 1/100
And the coliform group disappeared after treatment with the chlorine dioxide agent A (Example 9).

In the case of spicy mentaiko, the number of general bacteria is reduced to 1/100 by immersion in chlorine dioxide agent A at room temperature for 5 minutes (Comparative Example 21), but ultrasonic irradiation with chlorine dioxide agent A and room temperature for 10 minutes. Thus, the number of general bacteria was reduced to about 1/1000 (Example 10).

[0033]

[Table 3]

<Example 11, Comparative Examples 22 to 24> Chlorine dioxide agent A, sodium hypochlorite (50 ppm) and highly exposed flour (25 pp) for chicken skin (thigh skin with bone)
Table 4 shows the eradication results when the treatment according to m) and ultrasonic irradiation were used in combination. As shown in the column of water (control, Comparative Example 22), the microbial contamination of chicken skin used in this test was 3.8 × 10 ⁴ CFU / cm ^{2 for} general bacteria and 5.0 CF for coliform bacteria.
U / cm ² , fecal coliform group positive, Staphylococcus aureus
0 CFU / cm ² , a Salmonella-positive specimen. When this specimen was treated with chlorine dioxide A together with irradiation of ultrasonic waves (50 kHz), the number of general bacteria was reduced to about 1/1000, and the coliform group was completely eliminated. It was not detected and disappeared (Example 11). In addition, sodium hypochlorite (50 ppm)
In addition, when a combination of high-grade bleaching powder (25 ppm, a specific odor was found at a concentration higher than 25 ppm and cannot be used) and ultrasonic irradiation were used, only a slight improvement was observed as shown in Table 4 ( Comparative Examples 23 and 24).

[0035]

[Table 4]

<Preparation of Chlorine Dioxide Agent B> In the above-mentioned preparation of chlorine dioxide agent A, except that sorbitan fatty acid ester as a surfactant was not used, chlorine dioxide agent A was used.
Was prepared in the same procedure as in the preparation of

<Examples 12 to 23, Comparative Examples 25 to 27>
The difference in the eradication effect due to the difference in the order of the ultrasonic irradiation and the treatment with the chlorine dioxide agent, and the difference in the eradication effect with and without the surfactant were examined. Table 5 shows the results. In Table 5,
Sunny lettuce and broccoli, which are known as water-repellent vegetables, and chicken skin in which bacteria that inhabit the pores on the surface that are difficult to remove bacteria are problematic, are cited as samples. As shown in Table 5, the eradication rate increased in the presence of the surfactant, and the eradication rate increased (Examples 12, 14, 16, 18, 20, and 22). The presence of the surfactant promotes the penetration of the chlorine dioxide agent B into the pores on the surface of the specimen, and as a result, the chlorine dioxide agent B comes into direct contact with the microorganisms that live in the finest parts, thereby reducing the eradication rate. Suggests improved. In addition, when irradiation with ultrasonic waves and then sterilization treatment with chlorine dioxide agent B were performed, the sterilization rate was almost the same as when ultrasonic irradiation and treatment with chlorine dioxide agent B were simultaneously used, and the sunny lettuce was obtained. , Broccoli and chicken skin showed the same tendency (Examples 12 to 23). This indicates that the same effect can be obtained even if the treatment with the chlorine dioxide agent B is performed after the ultrasonic irradiation is performed first.

[0038]

[Table 5]

[0039]

As described above, in the sterilization method using the chlorine dioxide treatment and the ultrasonic irradiation in combination according to the present invention, since the ultrasonic irradiation and the treatment with the chlorine dioxide agent are performed, the removal of foods and the like is performed. Destroy colonies and clumps present in the fungus target,
Alternatively, the microorganisms inhabiting the pores on the surface of the object to be disinfected are exposed, and the chlorine dioxide agent comes into contact therewith, whereby an excellent disinfection effect can be obtained. This effect is remarkably exhibited in both the case where the chlorine dioxide treatment and the ultrasonic irradiation are performed simultaneously, and the case where the chlorine dioxide treatment is performed after the ultrasonic irradiation.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) A23L 3/26 A23B 7/156

Claims (11)

[Claims] 1. A sterilization method comprising irradiating an ultrasonic wave to an object to be sterilized in the presence of a chlorine dioxide-containing chlorine dioxide agent. 2. A step of irradiating the object to be sterilized with ultrasonic waves,
Contacting with a chlorine dioxide agent containing chlorine dioxide. 3. The method according to claim 1, wherein the chlorine dioxide agent contains a chlorite and a salt thereof. 4. The chlorine dioxide is prepared by converting chlorite and its salt to 2Na ₂ CO ₃ .3H ₂ O ₂ , NaHCO ₃ and NaBO _3.
The method of claim 1 or 2, wherein the method is generated from a stabilized chlorine dioxide agent stabilized by a stabilizer selected from the group consisting of: 5. The chlorine dioxide is generated from a chlorine dioxide agent that has been activated to generate chlorine dioxide by an activator selected from organic acids, mineral acids, hydrogen peroxide and alcohols. Claim 1 characterized by the following:
The method for removing bacteria according to any one of claims 1 to 4. 6. The sterilization method according to claim 1, wherein the concentration of the chlorine dioxide in the chlorine dioxide agent is 0.5 to 500 ppm. 7. The method according to claim 1, wherein the chlorine dioxide agent contains a hydrophilizing agent selected from the group consisting of alcohols and surfactants for hydrophilizing the hydrophobic surface of the object to be disinfected. The method for removing bacteria according to any one of claims 1 to 6, wherein: 8. The method for removing bacteria according to claim 1, wherein the object of bacteria removal is a fresh food or a food processing base material. 9. The vibration frequency of the ultrasonic wave is 5 to 150.
9. The method for removing bacteria according to claim 1, wherein the frequency is kHz. 10. The method according to claim 1, wherein the ultrasonic irradiation is performed at a temperature of 1 to 40 ° C. 11. The method according to claim 1, wherein the ultrasonic irradiation is performed for 1 to 30 minutes.