JPH0321416B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for sterilizing containers for aseptic filling and packaging of foods. [Prior Art] Various types of aseptic filling and packaging for beverages and other foods have already been put into practical use, but in general, containers are sterilized, drinks, etc. that have already been sterilized in a separate process are filled into the containers, and then the container is placed in a sterile atmosphere. This is known as aseptic filling packaging, which uses an aseptic filling and packaging machine that seals inside.
Most of these sterilization methods utilize the combined effect of hydrogen peroxide (hereinafter referred to as H ₂ O ₂ ) and heat. The container is formed before filling, and H ₂ O 2 with a concentration of about 35% is contained in the wrapping material sheet such as paper, film, aluminum foil, etc. used for forming the container, or inside the formed _container. After being sprayed, sterilization is performed using sterile air at a temperature of about 270 to 320 degrees Celsius. H ₂ O ₂ is often used at a concentration of 25 to 35%, and its bactericidal effect is known to be significantly more effective at high temperatures. Therefore, another method is to heat 35% H ₂ O ₂ to around 80°C and spray it onto the container. H ₂ O ₂ needs to be removed from the packaging material or container so that no residue remains after sterilization, but when drying with only heat such as heated sterile air, only the water evaporates, and the concentration of H ₂ O ₂ is high because it is originally high. may become even higher and remain. On the other hand, there are attempts to sterilize using heated saturated steam without using H ₂ O ₂ , but it requires sterilization at 149°C and 3.6 bar (3.55 atm).
This method requires high pressure and takes a long time to sterilize. Recently, a method has been proposed for sterilizing the surfaces of packaging materials, packaging machines and their ancillary equipment by means of a flow of a moist steam-air mixture having a temperature of 80-140°C and a moisture content of 5-50% (JP-A-Sho). 59−187525
There is also a proposal (Japanese Unexamined Patent Publication No. 2003-2013) to introduce heated steam from above as a sterilizing medium and discharge it from the bottom of the dish after forming the dish, in a method of manufacturing, sterilizing, and filling containers, etc. 60-45124) can also be seen.
In addition, in order to reduce the residual H ₂ O ₂ , the concentration
Attempts have been made to use % H ₂ O ₂ in combination with heat, but this has a low bactericidal effect, and the reality is that ultraviolet (UV) light is actually used to make up for the deficiency. Using this low concentration of H ₂ O ₂ ,
Recently, there has been a proposal (Japanese Patent Laid-Open No. 59-221227) to inject a spray nozzle with H ₂ O ₂ at a concentration of 1 to 20% into a columnar container, apply it evenly to the inside of the container, and then sterilize and dry it with sterile heated air. Can be seen. [Problems to be solved by the invention] The present invention solves the conventional problems in the method for sterilizing containers in aseptic filling and packaging as described above.
To provide an excellent container sterilization method capable of eliminating residual H ₂ O ₂ and significantly shortening sterilization time. [Means for Solving the Problems] The present inventor has discovered that in a conventional container sterilization method,
Sterilization methods that use 25-35% H ₂ O ₂ and heat have the problem of residual residue, while methods that use 1% H ₂ O ₂ and heat have poor sterilization effects, and high heat pressure saturation As a result of intensive research into the problem that it takes time to sterilize with water vapor alone, we found that
The present invention was achieved by discovering a method for sterilizing containers that does not leave any residual H ₂ O ₂ and can significantly shorten the sterilization time by treating with H ₂ O ₂ and using saturated steam under high pressure. It is. That is, the present invention is a method for sterilizing containers in aseptic filling packaging, in which the inner surface of a molded container is sterilized and then filled with sterile food in an _aseptic atmosphere _. This is a method for sterilizing containers, which is characterized in that H ₂ O ₂ is instantly boiled and evaporated by attaching the container to the container, then introducing it into a pressurized saturated steam atmosphere to sterilize it, and then exposing it to room temperature and pressure. The H ₂ O ₂ used in the present invention is used as H ₂ O ₂ water with a low concentration of 1 to 10%. If the concentration of H ₂ O ₂ is less than 1%, the bactericidal effect will be poor;
If it exceeds %, there is a risk of residue. inside the container
When sterilizing with H ₂ O ₂ , the inside of the container is usually coated by spraying, and this method is also adopted in the present invention. The amount of H ₂ O ₂ applied varies depending on the concentration, but an effect can be obtained between 0.5 and 2 g/m ² . Also,
Pressurized saturated steam is generated in a pressurized chamber equipped with a pressurized steam generator, but at a pressure of 1.5 to 3 Kg/ ^cm2.
It is preferable to use pressurized saturated steam at 100-130°C. Here, when the sterilization method of the present invention is applied to aseptic filling packaging, an outline of the steps from internal sterilization of a molded container to aseptic filling of a liquid food beverage to sealing of the container will be explained. . A molded container made from a sterilized packaging sheet is introduced into a sterilizer, and H ₂ O ₂ water with a concentration of 1 to 10% is sprayed onto the inside of the container to sufficiently coat the surface. After exposing the container to a pressurized saturated steam atmosphere in a pressurized chamber and sterilizing the inside of the container with H ₂ O ₂ using heat of 100 to 130 degrees Celsius, the container is filled with beverage in a filling device.
The lid is sealed and the product is made. As the container used in the container sterilization method of the present invention, any container formed from a single material or a composite material such as paper, plastic film, or aluminum foil can be used. In addition, the sterilization method of the present invention can provide excellent sterilization effects when applied to packaging materials, filling and packaging machines, and auxiliary equipment in addition to containers. [Example] Examples will be explained below. (Container used) Beverage container made from Honshu paper and plastic. Polypropylene is used for the circumference of the top and bottom and the support that connects the top and bottom, and the other parts are made of paperboard. A 250ml container made into a cylindrical shape (for planting Bacteria) Apply an average of 2 x 10 ⁴ Bacillus subtilis per container (sterilization treatment) Place the sample container in a retort tube and spray H ₂ O ₂ at the concentration shown in Table 1 for 1 second, then The sample is placed in a pressurized chamber with a saturated steam atmosphere at a temperature shown in , and the H ₂ O ₂ water is heated to rise to the saturated steam temperature, sterilized for 1 minute each, and then taken out at room temperature and pressure. For comparison, as shown in Table 1, sterilization was similarly performed using only pressurized saturated steam at 100° C. or higher without using H ₂ O ₂ . (sterilization effect) For containers that have been sterilized as described above,
The sterilization effect was tested. The results are shown in Table 1. From the results in Table 1, the concentration of the present invention is 1 to 10%.
Examples 1 to 4, in which H ₂ O ₂ water and heated saturated steam at 100°C or higher were used together, had better sterilization effects than those in which only heated saturated steam was used without using H ₂ O ₂ (Comparative Examples 1 to 3). is excellent.

〔Effect of the invention〕

The method for sterilizing containers of the present invention uses a low concentration method to sterilize containers, which conventionally used H ₂ O ₂ and sterile dry heated air.
By using H ₂ O ₂ together with pressurized saturated steam,
Eliminates the residual problem caused by the use of high-concentration H ₂ O ₂ , and also uses pressurized saturated steam and low-concentration H 2 O 2.
The synergistic effect of the combined use of H ₂ O ₂ improved the sterilization effect and significantly shortened the sterilization time. This improves the sterilization efficiency of the container, so by incorporating it into an aseptic filling and packaging machine for foods such as beverages, it can greatly contribute to improving the operating efficiency of the aseptic filling and packaging machine that operates continuously.
In addition, the sterilization method of the present invention can provide excellent sterilization effects when applied to packaging materials, filling and packaging machines, and auxiliary equipment in addition to containers.

Claims (1)

[Claims] 1 In a container sterilization method for aseptic filling and packaging, in which the inner surface of the formed container is sterilized and then filled with sterile food in an aseptic atmosphere, 1 to 10% of the inner surface of the container is
A method for sterilizing a container, which comprises depositing low concentration hydrogen peroxide on the container, then introducing the container into a pressurized saturated steam atmosphere to sterilize the container, and then exposing the container to room temperature and pressure to instantly boil and evaporate the hydrogen peroxide.