JP2001346509A - Method for sterilization of hen's egg - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for completely removing and sterilizing various kinds of bacteria attached to or included in the surface of egg shell, in consideration of the presence of the surface cuticle layer of the shell composed of 7-8 protein layers containing sugars and possible to diminish the effect of various bactericides on the bacteria existing in the layer and further promote the survival of the bacteria. SOLUTION: A hen's egg is sterilized by immersing the egg in a wood vinegar or spraying wood vinegar against the egg.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for sterilizing the surface of a shell of a chicken egg.

[0002]

BACKGROUND OF THE INVENTION Oviposition in chickens begins with ovulation, which is triggered by the formation of mature follicles in the ovaries, and ovulation occurs through the funnel, magnum, isthmus, shell glands, and the vagina of the eggshell. Done from At this time, in the vaginal part of the eggshell, mucus of protein containing sugar is secreted, and this smoothes the eggshell surface and facilitates oviposition. In this oviposition process, the eggs come into contact with intestinal bacteria at the total excretory opening where the bacteria adhere to the cuticle layer on the eggshell surface.

[0003] As described above, since the surface of the eggshell has a chance to come into contact with intestinal bacteria, various bacteria adhere to the cuticle layer on the surface even if it is visually clean.

When focusing on the safety of chicken eggs, countermeasures against Salmonella, one of the intestinal bacteria, have become the most important issue. The inspection of breeding chickens at the breeding grounds and the adoption of the HACCP system are also representative examples of the consciousness of eliminating this fungus.

[0005] However, the concept that the significance of the cuticle layer adhering to the egg surface lies in preventing the invasion of bacteria from the outside has priority, and the treatment of bacteria on the eggshell surface has been uniform. There is no way, and today each poultry farm or GP center has its own measures.

[0006] The cuticle layer on the surface of the eggshell contains 7 to 7 sugars.
It is composed of eight layers of proteins. If bacteria enter this layer, the efficacy of various fungicides will be reduced by half, and it is also thought that this contributes to the survival of bacteria. Can be

[0007] Under such circumstances, there has been a demand for a method of completely removing and sterilizing various kinds of bacteria attached (contained) on the surface of the eggshell.

However, as the method, generally, cleaning with warm water of 42 ° C. or less and chlorine-based disinfectant or ozone treatment are mainly used. However, sterilization by these methods has been questioned. According to the processing of this method, GP
According to the measured values of the center, the number of bacteria per 1 ml is 10 ² ~
Is 10 ^3, sterilized, which can be carried out in the course of mechanization is because has been difficult.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a method for sterilizing chicken eggs which enables sterilization of the eggshell surface.

[0010]

In order to realize the sterilization of chicken eggs, the present invention provides (1) a search for a substance capable of removing the cuticle layer in a short time, and (2) selection of a disinfectant capable of disinfecting the eggshell. These two issues were examined.

As a result, it has been found that "wood vinegar" obtained as a by-product during the production of charcoal has a function of expanding and peeling the cuticle layer. Then, when the dissociation mechanism was elucidated and its practical application was promoted, it was found that the cuticle layer could be easily separated by immersing the egg in wood vinegar or spraying the wood vinegar on the egg.

The bactericide, which has no persistence and has a broad antibacterial spectrum, was extracted and its practical concentration was examined.
A remarkable bactericidal effect was obtained by immersing the eggs in a 00- to 200-fold solution, particularly in a sodium hypochlorite solution, or by spraying these germicides on the eggs.

[0013] When the washing and sterilization of chicken eggs were elucidated, the mechanization of chicken egg sterilization was examined. If a mixture of wood vinegar and a bactericide was used, the combined effect of them was great and they could be used with existing egg washing machines. , And the prospect of a new plant was obtained.

[0014]

Embodiments of the present invention will be described below with reference to embodiments.

[0015]

EXAMPLE In this example, HACCP (Hazard Analysis Crisis) emphasizing the hygiene control of chicken eggs was used.
Tick control point method and, with the aim of long-term storage of chicken eggs, tests were conducted on the purification of bacteria adhering to the surface of the eggshell.

A. Test materials and test methods Test materials (1) Test eggs: Eggs of varieties (TX, W77, Isawhite, Julia, Chaparsole, Isarose) bred at Kanagawa Prefectural Livestock Research Institute were applied.

(2) Cleaning liquid: caustic soda, wood vinegar liquid (3) Disinfectant: sodium hypochlorite, soft oxidized water,
1. Glutaraldehyde, caustic soda, tincture of iodine Test method (1) Washing method of test eggs with water Running water washing: The test eggs were placed at a position of about 10 cm from a tap, and washed with running water for 30 seconds. Brush washing: The test eggs were washed with running water while rubbing well with a sponge scourer.

(2) Washing Method of Test Egg with Wood Vinegar Solution The test egg is immersed in the wood vinegar solution or the test egg is sprayed with the wood vinegar solution.
After leaving it for 3 minutes, it was brush-washed with running water.

(3) Method of cleaning test eggs with a germicide The concentration of each germicide used was 6% sodium hypochlorite solution,
A 25% glutaraldehyde solution, caustic soda and iodine tincture were adjusted with distilled water based on a 1.0% (100-fold solution) solution.

For soft oxidized water, Super C
What was adjusted with the lean-TE (OMCO) apparatus was used directly.

Washing of the test eggs was carried out by immersing the test eggs in the prepared liquid or spraying 5 ml of the prepared liquid on the test eggs by manual spraying.

B. Bacterial recovery method and egg quality inspection method Test eggs that had been washed and sterilized were immediately placed in a commercially available pack, allowed to stand at room temperature for about 1 hour, and then bacteria attached to the eggshell surface were recovered.

The recovery of bacteria was performed as follows. That is, first, a sterilized cotton swab was soaked in a small test tube containing 1 ml of physiological saline in advance, and the entire surface of the test egg was wiped off with the cotton swab.
After 0-fold serial dilution, 25 μl of these were diluted with DHL medium, 110 medium, TATAC medium, modified LBS medium,
The cells were inoculated into a UM medium, a blood agar medium and a Clostridia medium, cultured at 37 ° C. for 48 hours under aerobic culture and anaerobic culture using an anaerobic jar, and then the number of bacteria detected by the culture was calculated.

[0024] Egg quality was examined by a conventional method for egg weight, eggshell strength and hownit.

C. Test results 1. Contamination status of chicken eggs (1) Contamination status of non-washed eggs When the contamination status of 160 non-washed eggs was examined by the total number of bacteria, the minimum value (log) was 2. as shown in FIG.
556 / ml, the maximum value is 7.146 / ml,
It was found that the detection frequency was high around 5.000.

(2) Bacterial Type and Number of Bacteria Bacteria adhering to the surface of the egg were identified and the number of the bacteria was examined. As shown in Table 1, the total number of aerobic bacteria was 10 ⁴
〜１０10 ⁵ / ml, the total number of anaerobic bacteria was 10 ³ / ml, and no germ-free eggs were detected.

[0027]

[Table 1] E. coli (E. coli) was detected once out of four (40) tests, and showed a detection rate of 5% (2/40).
Aureus, Staphylococcus spp 10 ³ ~10 ⁴ / ml pieces, Streptococcus was 10 ² ~10 ⁴ / ml number range. The number of lactic acid bacteria was 10 ¹ to 10 ³ / ml, and the number of detected bacteria greatly fluctuated.

No anaerobic Clostridia genus was detected at all.

2. Washing effect of chicken eggs (1) In the case of washing with running water When the total number of bacteria was checked for 80 washing eggs with running water, the minimum value was 0.000 / ml and the maximum value was 5.380 / ml, which was 2.301. There was no following. Further, as shown in FIG. 2, one test egg (1.3) in which no bacteria were detected was detected.
%)was detected.

The cleaning effect is considered to be affected by the water temperature at the time of cleaning. Therefore, as shown in Table 2, there was no difference between the immersion and the brush cleaning. Average of 3.460 / m in tap water (18 ° C)
On the other hand, the average was 2.633 / ml in warm water, whereas the number of bacteria was reduced.

[0031]

[Table 2] (2) In case of brush washing The washing effect of 88 brush-washed eggs was further improved compared to running water washing, and as shown in FIG. 3, no bacteria were observed in 6 (6.8%).

(3) In the case of washing with wood vinegar The preliminary test confirmed that the wood vinegar had the function of expanding and exfoliating the protein adhering to the eggshell surface. The running water washing effect of the test egg was examined.

As a result, in the wood vinegar solution, the number of bacteria recovered by using the undiluted solution is 10 ² / ml or less, and conversely, the number of bacteria recovered by using a 10-fold or more diluted solution is increased to 10 ⁴ / ml. did.

As shown in Table 3, the effect of the immersion time was exhibited by immersion in the stock solution for 5 minutes, and showed almost the same value as immersion for 10 minutes.

[0035]

[Table 3] 3. Antibacterial effect of fungicide (1) Antibacterial effect of fungicide Five kinds of fungicides that can be sterilized in a short time were selected, and their antibacterial effects were compared using bacterial species collected from test eggs. As shown in the figure, the growth of bacteria was not observed in soft oxidized water 8 times, caustic soda 100 times, glutaraldehyde 200 times, sodium hypochlorite 3200 times, and iodine tincture 6400 times.

[0036]

[Table 4] Next, the antibacterial effect was examined by spraying each germicide or immersing each egg in each germicide on the unwashed eggs and the brush-washed eggs. An antibacterial effect was observed, showing a suppression rate of 80.0% by spraying and 60.0% by immersion. On the other hand, no bacteria were recovered from the brush-washed eggs by the treatment with sodium hypochlorite and glutaraldehyde in both spraying and dipping. In addition, there was no tendency of each of the germicides characteristic of the antibacterial effect of spraying and dipping.

[0037]

[Table 5] Then, when the antibacterial effect according to the concentration of each bactericide was examined for bacteria adhering to the eggshell surface after brush washing, as shown in Table 6, the spray was 0.8% for both sodium hypochlorite and glutaraldehyde. % Solution showed antibacterial effect, and soft oxidized water did not show that effect. In addition, in the immersion, antibacterial effect was observed in both sodium hypochlorite and glutaraldehyde up to 0.2% liquid, and the effect was confirmed in soft oxidized water in raw water.

[0038]

[Table 6] (2) Bactericidal effect of combined use of wood vinegar and sodium hypochlorite solution The bactericides used in this test have their own characteristics, and if anticipated to have a washing function for wood vinegar solution, hypobacterium has a low concentration and antibacterial function. Sodium chlorate can be selected. As a result of examining the combined effect, as shown in Table 7, the test eggs were simply immersed in a wood vinegar solution containing 1% of a 6% sodium hypochlorite solution for 5 minutes, and no bacteria were recovered at all. When the test eggs were immersed in a wood vinegar solution containing 0.1% or more of 6% sodium hypochlorite solution for 1 minute, the number of each bacteria was 1.84.
5, 1.954 and 1.447 / ml.

[0039]

[Table 7] (3) Effect of sterilization treatment on egg quality The cuticle layer on the egg shell surface was removed, and daily changes in egg weight, egg shell strength, howe unit and bacterial count were tracked.

As a result, as shown in Table 8, the measured values of the egg weight and the Howe unit decreased as the number of days passed regardless of whether the egg was treated or untreated, and the egg weight after 14 days was 3. 0 g and the untreated egg decreased by 2.4 g, and the Howe unit value decreased by 40.3 in the treated egg and 37.1 in the untreated egg.
The eggshell strength increased by 0.29 kg for the treated eggs and decreased by 0.44 kg for the untreated eggs. Regarding the number of recovered bacteria, 1/10 to 1 colony was detected on the 14th day of the treated eggs.

[0041]

[Table 8]

[0042]

(1) Normally, eggs are washed by showering or brushing with warm water of 45 ° C. or less, and the effect is low as can be seen from the results verified in the examples. The cause is thought to be the cuticle layer on the eggshell surface. Therefore, as a material for removing the cuticle layer, a wood vinegar solution having a function of expanding and peeling the cuticle layer in a short time was used. When the degree of removal of the cuticle layer by the wood vinegar solution was examined by the number of bacteria, it was reduced to 10 ² / ml or less, and it was found that the cuticle layer removal effect by the wood vinegar solution was remarkable.

The removal of the cuticle layer is experimentally performed by EDT.
A (Ethylen Diamond Tetraac)
etic Acid) and caustic soda. However, since this method cannot remove the eggs in a short time, the number of processed eggs per day in a chicken farm or a GP center is thousands or tens of thousands. Considering this, it seems that practical application of this processing method is difficult. On the other hand, the wood vinegar solution can be removed in a short time, so it can be said that it is an excellent removal material. However, since colored eggs are decolorized by removing the cuticle layer, the use of wood vinegar is limited to white eggs if discoloration is not desired.

(2) With respect to the germicides, both the sodium chlorite and glutaraldehyde germicides showed strong antibacterial activity. Among these, glutaraldehyde forms a pale yellow spot when this agent penetrates through the pores of the eggshell and reacts with the eggshell membrane. For this reason, there is a problem in persistence to eggs, and in this respect, there is a lack of practicality.

However, sodium hypochlorite disappears over time because the main component of sterilization is chlorine.
There is no problem in persistence, and it can be used for sterilizing chicken eggs. However, for the purpose of sterilizing chicken eggs, it is necessary that the total number of bacteria adhering to the washed eggs with water is 10 ² / ml or less. If it is more than this, it is desirable to use a wood vinegar solution that can be sterilized efficiently.

(3) It is conceivable that the disappearance of the cuticle layer on the egg shell surface or the treatment with sodium hypochlorite may have some effect on the subsequent egg quality. There was no abnormality in strength or how unit. From this, by washing and sterilizing chicken eggs with a mixture of wood vinegar and sodium hypochlorite, hygienic and safe eggs can be provided to consumers.

[Brief description of the drawings]

FIG. 1 is a graph showing the state of contamination of unwashed eggs.

FIG. 2 is a graph showing the state of contamination of running water washed eggs.

FIG. 3 is a graph showing the contamination status of the brush-washed eggs.

Claims (3)

[Claims] 1. A method for sterilizing chicken eggs, comprising immersing chicken eggs in wood vinegar or spraying chicken eggs with wood vinegar. 2. A chicken egg is immersed in a sodium hypochlorite solution,
Alternatively, a method for sterilizing chicken eggs, which comprises spraying the aforementioned sodium hypochlorite solution on chicken eggs. 3. A method for sterilizing chicken eggs, comprising immersing the chicken eggs in a wood vinegar solution containing a sodium hypochlorite solution, or spraying the chicken eggs with the wood vinegar solution.