WO2011162494A2

WO2011162494A2 - Method for inhibiting harmful insects in food package by nitrogen-substitution packaging

Info

Publication number: WO2011162494A2
Application number: PCT/KR2011/004216
Authority: WO
Inventors: Ja-Hyun Na; Dae-Sub Shin; Hyun-Woo Yu; Yong-Soong Lee; Tae-Hoon Kim; Mun-Il Ryoo
Original assignee: Cj Cheiljedang Corp.
Priority date: 2010-06-22
Filing date: 2011-06-08
Publication date: 2011-12-29
Also published as: KR20110138876A; WO2011162494A3

Abstract

The present invention relates to a method for inhibiting harmful insects in the food package by the nitrogen-substitution packaging in which the remaining amount of oxygen at the inside of the food package become 5% below when packaging food by a nitrogen-substitution packaging. According to the present invention, since the residual amount of oxygen within the inside of the food package is maintained at 5% below, the hatching and development of the eggs of harmful insects can be inhibited effectively, so the distribution period of products can be largely extended. Also, the claim of harmful insects may be occurred due to the contamination of the harmful insects during the production can be effectively inhibited.

Description

METHOD FOR INHIBITING HARMFUL INSECTS IN FOOD PACKAGE BY NITROGEN-SUBSTITUTION PACKAGING

The present invention relates to a method for inhibiting harmful insects in a food package by a nitrogen-substitution packaging. More specifically, the present invention relates toa method for inhibiting harmful insects in the food package by the nitrogen-substitution package in which the residual amount of oxygen in the food package exists 5% below when packaging the food by the nitrogen-substitution packaging.

After the year of 2000, the advancement of technical development in several industrial fields affected directly consumer s preference and standard of living andthe preference and requirement of the consumers also has been changed variously and concretely. Packaging technologies of goods have been developed to match commercialization toward high-tech packaging technology to enhance the value of goods and to provide functionality on the basis of fundamental elements, such as protection, convenience, and communication of sales, away from packaging for a conventional simple product protection function.

Generally, a packaging technology may be the most widely applied to a food industryand is in charge of an important role in commercialization of the food products. Packaging technologies havebeen used to supplement the weak point of the product, to extend the expiry date of goods, and to maintain and improve the quality of goods in various aspects such as the treatment of goods, the production of goods, the process of packaging, the treatment of packaging, storage and distribution of goods.

Most of foods aredecayed rapidly by loss and absorption of moisture, a reaction to oxygen, and the growth of aerobic microbes such as bacteria and mold and the like according to a gas environmental condition at the circumference of goods. The growth of microbes caused changes of a sense of texture, color, and flavor, and a nutritional change in food products. These changes may generate problems of safety and hygiene to consumers for purchasing the food products.

Accordingly, an application of gas to a food packaging includes the quality and freshness maintenance functions, the prevention from the growth of microbes or other contamination from outside of a package, and a function for removing oxygen generating decay of a product besides microbes and also various commercially packaging treatment technologies have been applied to protect effectively products and to provide commercialization from the various factors affecting the quality change.

For example, a gas removing packaging is a technology that the storage lifespan in food and medicines is extended through the adsorption of oxygen or ethylene, carbon dioxide and moisture by the application of an active absorbent at the inside of a package and in the packaging material. An active material emission packaging, on the contrary to the absorbent,is a technology that an activator as antimicrobial such as carbon dioxide and ethanol and the like is mainly released from the packaging material so that the quality of food and drug medicine is extended. Also, a gas control packaging is a technology that the composition of gas necessary to the food in the package is made by maintaining the proper transmittance of oxygen or moisture, thus extending the storage lifespan of the food.

Also, the deterioration of quality or a lowering of freshness of food can be prevented by blocking out the influence by oxygen through an oxygen removing packaging technology such as a vacuum packaging and a gas substitution packaging process using nitrogen. Since some oxygen also remained in the gas substitution packaging, the oxygen removing technology may be used in order to completely remove the residual oxygen(0.5~1%) through a sealing packaging of oxygen adsorber.

Also, after sealing the packaging, the packaging is performed by using packaging materials with an excellent gas blocking property in order not to be passed through oxygen from the outside of the package to the inside of the package.

Three important gases mainly used to a gas substitution technology are O₂, CO₂, and N₂ or inert gas. These gases used solely or by mixture are generally used for optimizing food properties and for extending a safe expiration date. Also, the experimental uses of CO and SO₂ have been reported.

Nitrogen among these gases is to prevent the growth of aerobic microbes, has a low solubility characteristic, and is used many as a CO₂/N₂ mixing gas containing nitrogen gas enough to the food packaging. By using this, the volume contraction of the package which may be caused by high solubility of CO₂ can be prevented.

Also, although inert gases such as He, Ar, Xe, and Ne areapplied and used to many foods such as potato snack products and the like, it is hard to find anotherremarkable advantages compared to nitrogen having been used in present.

As described above, the gas substitution packing technology has beenapplied to dairy products, raw red meat, raw poultry, cooked, cured and processed meat products, fish and fish products and fresh fruit and vegetables.

The application types of the gas substitution packaging technology can be classified largely with a nozzle type, a chamber type, and a gas flash charging type and a gas is charged and substituted in the package. The nozzle type is as follows: air at the inside of the package including food is exhausted by a nozzle inserted into the inside of the package and then sealed by nitrogen or carbon dioxide gas. Although this type is cheap and simple in a manipulation method compared to other types, there is a drawback that oxygen in the package does not completely removed. The chamber type is mainly used to a flexible package and a formed tray package. According this method, a package containing food is fixed within a chamber, the chamber is sealed and then air at the inside and outside of the package containing food is exhausted by a vacuum pump. After fully exhausting, gas is injected into the inside of the package and the inlet portion is sealed. This method is mainly used to meat products or fish products. The gas flash type is as follows: gas is flashed directly without an exhausting process. According to this method, the contents of the package is packaged by a pillow packaging device with a roll shape of film and thereafter nitrogen or carbon dioxide gas is flashed into the package before sealing the package. According to this method, although a high-speed gas charging is possible, since the substitution of air is incomplete and the residual oxygen concentration reachesgenerally 1~2%, this method is mainly applied to package snack, coffee, and potato chips and the like.

According to Korean Patent Application No. 10-1993-0010638 under the title of "a method for preserving a waste water purifying microorganism agent", when packagingthe microorganism agent, air within pouch film is substitutedby nitrogen gas and then a seal process is performed. Also, according to Korean Patent Registration No. 10-0488472 under the title of "a packageof food using inert gas", air within a food package containeris substituted by inert gas and so oxidation of food and proliferation of microorganism related to decay of food by oxygen existing in the air in the package container are prevented, thereby enhancing the preservability of goods. Also, according to Korean Patent Registration No. 10-0678749 under the title of "a method for packaging meat products" which discloses for sealing meat products at the inside of a package container, air at the inside of the package container is substituted into a mixing gas which consists of 0.33 volume % of CO, 66.67 volume % of CO₂, and 33 volume % of N₂.

Also, according to Korean Patent Application No. 10-2008-0041382 under the title of "a method for preserving mushroom, it discloses that deodorant is inserted into a package container and thereafter air in the package container is substituted into gas. According to the Korean Patent Registration No. 10-0659354 under the title of "a method for packaging mushroom by a gas substitution", it discloses that mushroom is sealed and packaged and then air in the package container is substituted into gas including nitrogen, oxygen, and carbon dioxide.

On the other hand, food products are delivered to end consumersthrough several steps such as production, storage, and distribution and the like. During the above steps, contamination due to harmful insects can be occurred, and especially, the possibility of contamination is high at the distribution step in transactions between nations with a long term transportation period. As it turned out, harmful insects are developed to stages of an egg, a larva, and an imago and have other ecological characteristics that the degree of development at each development stage is largely changed by a development condition such as temperature and food and the like and periods required for a complete development from an egg into an imago arerevealed differently.

There are several damages due to harmful insects during the storage of food products. Grain is consumed by harmful insects, the grain is damaged by harmful insects droppings and secretion of their cadavers, thereby lowering quality of it, and there is also an indirect damage through theinteraction between harmful insects and microorganism. At the low temperature, the development of harmful insects is inhibited, and if humidity rises in some degree in the air, the propagation of harmful insects becomes vigorous. As examples of storage harmful insects, there are Aitophilus oryzae,Sitophilns sasaki taka, Platypodidae, Plodia interpunchtella, Aphomia gularis zell, Sitotroga cerea-lella olivo and the like.

As a study for preventing generation of harmful insects during the food storage, "Control of Food Pests by CO₂ Modified Atmosphere: Effects of Packing Materials and Exposure Time on the Mortality of Tribolium castaneum and Plodia interpunctella"(Ja Hyun Na, Youngwoo Nam, Mun il Ryoo and Yong Shik Chun, Journal of Korean Society of Applied Entomology, Vol. 45, No. 3, the whole vol. No. 1442006.12; pp363-369) had been studied.

Also, Korean Patent Application No. 10-2005-0015703 discloses a method for manufacturing harmful insect prevention package paper using anion and alum composite. Also, according to Korean Utility Model Registration No. 20-0288031, a product is packaged in order to may be discharged air at the inside of it into the outside of it through plural air discharge holes, so that the decay of food sealed by the package is preventedat processes of storage, transportation and display for selling, and also the invasion of ants and small insects into the packaged food products is prevented. Also, according to Korean Patent Application No. 10-2001-0039381 under the title of "a method for manufacturing food package materials contained mugwort extract and mugwort juice", the mugwort extract and mugwort juice with an antibacterial activity are added into the food package materials, thereby preventing basically the propagation of harmful insects.

Like this, although various techniques has been studied in order to prevent harmful insects which may be generated at the inside of the food package, these studies are mainly biased at the part for developing the new package materials.

Inventors according to the present invention has been studied continuously in order to develop a method for preventing harmful insects at the inside of the food package, so that it is confirmed that when residual amount of oxygen is decreased by substitution of the air at the inside of the package through nitrogen, the harmful insects are effectively prevented. So, the inventors have unearthed an optimum nitrogen substitution method for preventing the harmful insects through experiments, so that the present invention has been completed.

Therefore, the present invention has been made in order to solve problems that in case of a nitrogen charging method has been currently used, at a separate charging process together with a food product or after insertion of a food product, a charging gas with a constant high pressure (3~5 bar, 1 bar is an atmospheric pressure) is pushed into the package and then the package is sealed, so that it is difficult to maintain a residual amount of oxygen at 5% below, and especially, in case that particles of a product are small, the product is scattered when charging, the product is packaged with the excessive residual amount of oxygen due to anair gap within the product.

In order to overcome the above problems, the present invention provides with a method for sealing (hereinafter, a nitrogen substitution method ) in which a charging gas together with a product is firstly pushed in a package and supplied into between air gaps within the product, and secondly, input and output gas flow speeds are maintained identically by using a nozzle, oxygen at the inside of the package is substituted into the charging gas, the gas concentration of an output nozzle is measured after the substitution during a constant time, and the package is sealed when the residual amount of oxygen become 5% below.

According to a method of the present invention, the residual amount of oxygen at the inside of the food package is 1% below.

According to a method of the prevention invention, the package is preserved for 14 days or more after a nitrogen charging packaging and then opened.

According to a method of the present invention, the package is preserved for 7 days or more after a nitrogen charging packaging and then opened.

According to a method of the present invention, in the food packaging, aproduct is packaged with an amount of 50 wt% below compared to the packaging volume of the package materials.

As described above, the method of the present invention is achieved by: in case that a product is contaminated by eggs of harmful insects at a nitrogen charging packaging condition, the possibility of hatching of the eggs of the harmful insects according to the nitrogen charging amount and the packaging condition maintaining periodis examined by using Plodia interpunctella among food storage harmful insects and the lowest preservation period at the optimum nitrogen charging amount and state is established.

In the present invention,in order to find the optimum nitrogen charging amount and the optimum nitrogen charging maintaining period when packaging the food by the nitrogen substitution, eggsof Plodia interpunctella as a test insect are packaged together with an experimental sample as different charging amount packages, the residual amount of oxygenwithin the package according to the passing of period is examined, the package is opened at every period, preserved at the same condition, and then the hatching of the eggs and the development of the larvae (silkworm, cadaver) are examined.

As an examination result of the residual amount of oxygen according to date, it is disclosed that in case of packaging with the residual amount of oxygen of 0.5 and 1%, the development after the hatching of the eggs is impossible at the inside of the package. Also, since the pressure at the inside of the package is lower than that at the outside of the package, the diffusion of oxygen from the outside to the inside of the package is superior to the diffusion of nitrogen from the inside to the outside of the package under the transmittance of the package, thereby increasing the concentration of oxygen.

Also, it is disclosed that in case of the package with the residual amount of oxygen of 3 and 5%, the development after the hatchingof the egg during a constant period is possible at the inside of the package. Also, since the pressure of the total gas at the inside and outside of the package is similar to each other, it is possible to maintain the concentration of gasunder the transmittance of the package, so that the increase of the concentration of oxygen is imperceptible.

As a result that the accumulated hatching rate of eggs of a harmful insect according to date is examined, in case of experimental groupswith the residual amount of oxygen of 0.5% and 1%, when opening the package at 1, 3, 7, 14, 21 and 28 days, there are no vestiges of hatching and development. However, the vestiges of hatching and development (silkworm)are discovered after the lapse of 3 to 7 days from when opening the package at 1, 3, and 7 days. Also, the vestiges of hatching and development did not observed when preserving the package after opening the package since 14 days. When the hatching of the eggs of plodia interpunctella is delayed, the egg did not died until 7 days, and their activity is maintained and changed into the hatching possibility environment, the egg is hatched. However, the egg did not hatched after 14 days.

In case of experimental groups with the residual amount of oxygen of 3% and 5%, when opening the package at 1 day, there are no vestiges of hatching and development. However, the vestiges of hatching and development (silkworm, cadaver) are discovered within 2~3 days after opening the package, the partial hatching vestige is discovered when opening the package at 3,7,14,21 and 28 days. Also, the vestiges of hatching and development are clearly observed when preserving the package after opening it in case of 3 and 7 days. However, the vestiges of hatching and development are not clearly observed after 14 days.

From the above, although the hatching of plodia interpunctella harmful insect eggs can be inhibited when the passing of 7 days or more with the residual amount of oxygen of 1% below, the standard of the package is increased in case of 3 and 5%, and in case that the total residual amount of oxygen is increased, it is discriminated that the hatching and development of the harmful insect eggs are possible until a constant day period (two days).

In case that a nitrogen charging state is maintained for 14 days or more in the nitrogen substitution package state at the every concentration, the hatching of the harmful insect eggs is possible and the development of it is impossible.

As a result, the inventors obtained the most effective result for inhibiting the harmful insects within the inside of the food package: the inside of the food package is substituted by nitrogen so that the residual amount of oxygen at the inside of the package of the package food become 5% below, the package is preserved for 14 days or more after the nitrogen substitution packaging, or the inside of the food package is substituted by nitrogen so that the residual amount of oxygen at the inside of the package of the package food become 1% below, the package is preserved for 7 days or more after the nitrogen substitution package and opened.

Through a method of the present invention, for example, the harmful insects such as Aitophilus oryzae, Sitophilns sasaki taka, Platypodidae, Plodia interpunchtella, Aphomia gularis zell, Sitotroga cerea-lella olivo and the like can be inhibited and however, the method according to the present did not limited to those harmful insects, other all harmful insects which may be generated at the inside of the food package can be included.

According to the present invention, since the residual amount of oxygen within the inside of the food package is maintained at 5% below, the hatching and development of the eggs of harmful insects can be inhibited effectively, so a distribution period of products can be largely extended. Also, a harmful insect claim which may be occurred due to contamination of the harmful insects during the production can be effectively inhibited.

Also, according to the present invention, since the secondary nitrogen charging is performed through a nozzle, a problem of the product scattering is decreased.

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a graph illustrating changes of nitrogen charging amount after substituting nitrogen within apackage and the residual amount of oxygen according to the passing of day.

Fig.2 is a graph illustrating a nitrogen charging amount after substituting nitrogen within a package and an accumulated hatching rate of plodia interpunctella according to the passing of day.

Now, the present invention will be described in more detail with reference to the following Examples. These examples are only provided to illustrate the present invention and should not be construed as limiting the scope and spirit of the present invention.

Example 1: Nitrogen Substitution Packaging

In this example, in case that a product is contaminated by eggsof a harmful insect at a nitrogen substitution packaging condition, the eggs of a test insect are packaged together with the test sample with different nitrogen charging amounts in order to examine the hatching possibility of the harmful insect eggs according to the nitrogen charging amount and packaging condition maintaining time. Eggs of 24 hours below from the spawning time of plodia interpunctella raised by artificial feed are used as a test insect and elementary partcle flour(semolina) is used as an experimental sample.

At first, 8.4kg of elementary particle flour is mixed with eggs of 500 or more of plodia interpunctella at each 500g unit in order to be distributed uniformly the eggs, thereby obtaining the experimental material. The obtained experimental material is pushed into the package paper with an amount of 8g by 4g.

Then, when packaging the experimental material, nitrogen is charged so that the residual amount rate of oxygen become 0.5,1,3, and 5%, respectively (refers to a Table 1).

Table 1

Classification	Residual rate of oxygen/The number of packages
Classification	waiting	0.5%	1%	3%	5%
The number of Packages	360	240	360	360	360
Oxygen rate when packaging	20.19 ±0.054	0.185 ±0.042	1.059 ±0.061	3.321±0.043	4.828±0.159

Each package manufactured as above is maintained and preserved for 1,3,7,14,21, and 28 days at the condition of 28~32℃ and 60~70RH.

Example 2: Examination of Residual Amount Change of Oxygen within a Package

In this example, in order to find the residual amount change of oxygen within a package at each package manufactured and preserved at the example 1, the residual amount change appearances are examined by 1,3,5,7 day(s) and a week unit at the experimental condition (7~10 units by each concentration and day.

As a result, as shown in a Table 2 and Fig. 1 below, it is disclosed that in a control group charged by the air, the residual amount of oxygen is decreased and an amount of carbon dioxide is increased. It is thought as a result that the eggs are hatched and thereafter when breeding the hatched eggs, the oxygen is substituted into carbon dioxide through breathing within the package.

Also, it is disclosed that in case of experimental groups packaged by residual amount of oxygen of 0.5 and 1%, respectively, the development is impossible after hatching eggs within the package and since the pressure at the inside of the package is lower than that atthe outside of the package, the diffusion of oxygen from the outside to the inside is superior to the diffusion of nitrogen from the inside to the outside under the transmittance of the package, thereby increasing concentration of oxygen.

Also, it is disclosed that in case of experimental groups packaged by residual amount of oxygen of 3 and 5%, the development is possible after hatching the eggs during a constant period at the inside of the package. Also, since the pressure of the total gas at the inside and outside of the package is similar to each other, it is possible to maintain the concentration of gas under the transmittance of the package, so that the increase of the concentration of oxygen is imperceptible.

Table 2

Example 3: Examination of Accumulated Hatching Rate

In this example, each package manufactured and preserved at the above example 1 is opened and preserved at the same condition and the hatching of eggs and the development of larvae (silkworm and cadaver) are examined.

In the examination of the existence of hatching of plodia interpunctella eggs, the cumulative examination of the development residue in total opening samples at the time of opening and the next opening date after preserving is performed. The existence of hatching of plodia interpunctella eggs is observed through cadavers of larvae, observation of silkworm, and an examination of the development wastes by a high-powered microscope (90 times).

As a result, as shown in a Table 3 and Fig. 2 below, in a control group, after the passing of 3~4 days as the previous plodia interpunctella eggs, the eggs are hatched and can be developed. When opening from the packaging of one day, the hatched larvae cannot be observed and however, when opening the package from the packaging of 3 days, the larvae and silkworm are discovered. When hatching the eggs at the inside of the package, oxygen at the inside of the package is substituted into carbon dioxide through the breathing and as a result, the surviving larvae are discovered until the package of 7 days. However, only dead larvae are discovered in the package afterthe package of 14 days due to the inhibition of breathing caused by shortage of oxygen.

Table 3

Classification	Waiting	0.5%	1%	3%	5%
1 day	10030/30	10020/20	10030/30	10030/30	10030/30
3 days	10030/30	10020/20	10030/30	10030/30	10030/30
7 days	10030/30	81.2513/16	86.6726/30	93.3328/30	96.6729/30
14,21, and 28 days	10030/30	00/20	00/30	00/30	00/30

In case of experimental groupswith the residual amount of oxygen of 0.5% and 1%, when opening the package at 1, 3, 7, 14, 21 and 28 days, there are no vestiges of hatching and development. However, the vestiges of hatching and development (silkworm) are discovered after the lapse of 3 to 7 days from when opening the package at 1, 3, and 7 days. Also, the vestiges of hatching and development did not observed when preserving the package after opening the package since 14 days. When the hatching of the eggs of plodia interpunctella is delayed, the egg did not died until 7 days, and their activity is maintained and changed into the hatching possibility environment, the egg is hatched. However, the egg did not hatched after 14 days.

In case of experimental groupswith the residual amount of oxygen of 3% and 5%, when opening the package at 1 day, there are no vestiges of hatching and development. However, the vestiges of hatching and development (silkworm, cadaver) are discovered within 2~3 days after opening thepackage, the partial hatching vestige is discovered when opening the package at 3,7,14,21 and 28 days. Also, the vestiges of hatching and development are clearly observed when preserving the package after opening it in case of 3 and 7 days. However, the vestiges of hatching and development are not clearly observed after 14 days.

From the above, although the hatching of plodia interpunctella harmful insect eggs can be inhibited when the passing of 7 days or more with the residual amount of oxygen of 1% below, the standard of the package is increased in case of 3 and 5%, and in case that the total residual amount of oxygen is increased, it is discriminated that the hatching and development of the harmful insect eggsare possible until a constant day period (two days).

In case that a nitrogen charging state is maintained for 14 days or more in the nitrogen substitution package state at the every concentration, the hatching of the harmful insect eggs is possible and the development of it is impossible (the egg is died at the 1 day state after hatching, so the observation is impossible by a naked eye).

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

A method for inhibiting harmful insects in a food package by nitrogen-substitution packaging, wherein the residual amount of oxygen at the inside of the food package is 5% below.
The method according to claim 1, wherein the residual amount of oxygen at the inside of the food package is 1% below.
The method according to claim 1, wherein in the food packaging, a product is packaged with an amount of 50 wt% below compared to the packaging volume of the package materials.
The method according to claim 1, the food package is preserved for 14 days or more after a nitrogen charging package and then opened.
The method accordingto claim 1, the harmful insects are one or two or more insects selected from a group consisting of Aitophilus oryzae, Sitophilns sasaki taka, Platypodidae, Plodia interpunchtella, Aphomia gularis zell, Sitotroga cerea-lella olivo and the like.