JPH024692A - Method and apparatus for aseptic filling of pet bottle - Google Patents

Abstract

PURPOSE:To fill a PET bottle with a perishable beverage in an aseptic state by filling the PET bottle with a sterilizing solution and sterilizing the filled bottle while reciprocally shaking the same on a conveyor for a required time and, after removing the sterilizing solution, washing the bottle with aseptic water to fill the same with the beverage. CONSTITUTION:A PET bottle is successively supplied from a region A in such a state that the bottom thereof is turned downwardly to be introduced into a preparatory washing apparatus 1 and, subsequently, a sterilizing solution is injected in the PET bottle so as to overflow and the filled bottle is guided to a reciprocating shaking conveyor 2 by the conveyor in a tunnel 7 in which aseptic air is supplied. The PET bottle filled with the sterilizing solution is allowed to reciprocate several times by the conveyor while shaken on the reciprocating shaking conveyor 2 to allow the sterilizing treatment in the bottle to advance. The PET bottle passed through the conveyor 2 is introduced into a sterilizing solution removing outside washing apparatus 3 through the tunnel 7 and the outside of the bottle is washed while the sterilizing solution therein is discharged. Next, the bottle is introduced into an aseptic water washing apparatus 4 through the tunnel 7 to be washed with aseptic water in order to remove the remaining sterilizing solution and subsequently introduced into a filling apparatus 5 to be filled with a perfectly sterilized beverage.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method and apparatus for aseptically filling food, especially beverages, into polyethylene terephthalate bottles, commonly known as PET bottles.

(Prior Art) PET bottles, that is, bottles made of polyethylene terephthalate resin, are used for foods, especially juices, oolong tea,
It is extremely suitable for filling beverages such as tea, coffee, and milk-containing beverages, but unless it is thoroughly sterilized, it cannot be kept on store shelves at room temperature because it will deteriorate.

In the case of canned food, retort pouched food, and cup-packed food, heat sterilization is performed after filling.On the other hand, aseptically filled food in canned food, paper, and plastic cups is sterilized with superheated steam at around 300°C. In the case of paper and plastic cups, the containers are sterilized by UV irradiation, immersion in hydrogen peroxide solution, and spraying, followed by drying, and then filled aseptically with food that has been sterilized using a heat exchanger to prevent deterioration. However, in the case of PET bottles, heat sterilization may cause the PET to shrink, and even if UV rays are irradiated from outside the bottle, the PET
Since the benzene rings present in ET resin absorb ultraviolet rays, the bactericidal effect is not exhibited.

In addition, if you use hydrogen peroxide dipping and spraying, the sterilizing effect of hydrogen peroxide is only when the hydrogen peroxide dries, so if you use hydrogen peroxide to sterilize the container, Drying after hydrogen peroxide treatment is essential.

Furthermore, since PET bottles are stretch-molded, they have residual stress, and a fatal drawback arises in that the PET bottles shrink when dried after being immersed in hydrogen peroxide and sprayed.

(Problems to be Solved by the Invention) Foods, especially highly perishable beverages such as milk-containing beverages, can be heated or sterilized after filling, or aseptically filled using superheated steam method, ultraviolet irradiation sterilization method, and
To provide a method and an apparatus for filling PET bottles in an aseptic state without using a post-heat drying sterilization method for hydrogen peroxide dipping or spraying.

(Means for Solving the Problems) In order to solve the above problems, the present inventors conducted extensive research and found that it is effective to sterilize PET bottles and then fill them with sterilized filling liquid. Ta.

Then, we decided to use an aqueous solution of a sterilizing agent (sterilizing liquid) to sterilize the PET bottles. Since sterilization using a sterilizing solution requires a longer time than sterilization using heat or ultraviolet light, complete sterilization was achieved by moving the material back and forth on a belt conveyor for the required period of time while shaking.

The method of the first invention and the apparatus of the second invention were invented by adopting a method of completely rinsing away the sterilizing liquid by pouring sterile water instead of using heating and drying.

That is, in the first and second inventions, PET bottles are preliminarily washed with a sterilizing solution in a sterilized space, then filled with the sterilizing solution, placed on a conveyor, and shaken back and forth for a required period of time to sterilize the bottle. then invert the bottle to remove the sterilizing solution, wash the outside of the bottle, and then
A method for aseptically filling a PET bottle, characterized in that the inside of the bottle is washed with sterile water to wash away a sterilizing solution, the filling solution is then filled, and then a sterilized cap is placed on the bottle.

a reciprocating shaking conveyor 2 that moves in opposite directions, and a sterilizer removal outer cleaning device rI13 connected to the conveyor that overturns the PET bottles to remove the sterilizing solution and then cleans the outside of the PET bottles; It consists of a sterile water cleaning device 4 disposed next to the cleaning device for cleaning the inside of the PET bottle with sterile water, a filling device 25 connected to this cleaning device, and a capping device 6 for covering the cap. , each device is connected by a conveyor, and each device and the conveyor are provided with a tunnel 7 through which sterilized gas is supplied.
This is an aseptic bottle filling device.

However, when the present invention is carried out using the filling device of the present invention, sterilization may fail, although it is extremely rare.

In this case, the inventors conducted further research and found that in step 4, where sterile water is injected into the PET bottle that has been sterilized and the liquid has been discharged for washing, from the rotary joint part that flows sterile water, This problem was solved by identifying the contamination of germs and forming a barrier of sterilizing liquid in that area, thereby completing the third invention.

That is, the third invention provides a sterile water cleaning device 4 in which P.
Rotary packing 101 of rotary joint 100 that rotates while sending sterile water into the ET bottle
The gap 106 between the stop ring 102 that fixes the ball bearing 103 and the stop ring 105 that fixes the ball bearing 103 by sandwiching the spacer 104 is filled with sterilizing liquid or sterile water to form a barrier to prevent bacteria from entering.
The filling device according to claim 2, wherein the filling device is kept in a sterile state.

(Example) An example of the present invention will be described using FIGS. 1 and 2.

Example 1 FIG. 1 is a plan view of a specific example of the aseptic filling device of the present invention.

In FIG. 1, PET bottles with their bottoms facing down are sequentially loaded starting from A and introduced into the pre-washing device 1.

Next, the drug P3-HTW (sterilizing liquid) was injected into the PET bottle so that it overflowed, and then introduced into the reciprocating shaking conveyor 2 by a conveyor in the tunnel 7 to which sterilized gas was supplied.

The PET bottles filled with medicine are transferred to the reciprocating rR conveyor 2.
While being shaken on top of the bottle, the bottle is moved back and forth several times by a conveyor, and the sterilization process inside the bottle progresses.

At this time, the sterilizing solution may spill due to shaking, so
Additional orders will be made if necessary. Reciprocating shaking is carried out for a sufficient period of time to ensure sufficient sterilization.

The PET bottles that have passed through the reciprocating shaking conveyor 2 are introduced through a tunnel 7 into a disinfectant removal external cleaning device 3 .

In the disinfectant removal external cleaning device 3, the outside of the PET bottle is cleaned while the PET bottle is turned upside down and the disinfectant liquid inside is discharged. At this time, it is usually washed with sterile water, but a sterilizing solution can also be used if necessary.

Then, it was introduced into a sterile water washing device=4 through tunnel 7, and washed with sterile water to remove the remaining sterilizing solution.

Next, the PET bottle is placed with the mouth up and the bottom placed back down, introduced into the filling device 5, filled with completely sterilized oolong tea, and introduced into the capping device 6, where the sterilized gear is capped. , B
Oolong tea products in PET bottles were also loaded.

The contents of the obtained product did not deteriorate even after being left at room temperature for one year.

Comparative Test 1 Instead of the oolong tea filled in implementation S1, 1.51 parts of completely sterilized water and 7 parts of meat extract! 5t, peptone 15
t, the case where the liquid suitable for the growth of microorganisms containing 7.5 g of sodium chloride was filled, and the case where the reciprocating rR shaker conveyor 2 was not used and the same procedure was performed except that the liquid was allowed to stand still for the same time. The presence or absence of defeat was observed after being left at room temperature for one month.

The results were as shown in Table 1.

Table 1 In complete sterilization filling, one defective product out of 10,000 means that this filling method itself is extremely defective.

Embodiment 2 FIG. 2 is a sectional view of a rotary joint used in the third invention.

This rotary joint introduces sterile water from C and
It is used to flush out the inside of the PET bottle and rotate around the vertical center line by sliding on the rotative packing 101 and the lower stop ring 102. There is.

In the present invention, a gap 106 is provided between the lower stop ring 102 and the upper stop ring 105, and sterile water or sterilizing liquid is injected into this gap from A to form a barrier layer, and is discharged from B. It has become.

Therefore, even if the rotative packing 101 becomes depressurized when sterile water flows in the direction from C to D, no bacteria will be sucked in.

In the sterile water washing step of Example 1, a milk-containing beverage was filled using the sterile water washing device 4 equipped with the rotary joint in which the rotating part was provided with a barrier layer.

The contents of the obtained product did not deteriorate even after being left at room temperature for one year.

Comparative Test 2 In place of the milk-containing beverage filled in Example 2, the same liquid as that used in Comparative Test 1 was filled, and in the above case, sterile water equipped with a rotary joint without a barrier layer was used. The same procedure was performed except that the samples were washed with a washing device (rinser), and the presence or absence of deterioration of both samples was observed after one month of leaving them at room temperature.

The results were as shown in Table 2.

In the completely sterilized filling shown in Table 1, the fact that there is one defective product in every 100,000 bottles means that this filling method itself cannot be put to practical use.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of an aseptic filling device, and FIG. 2 shows an embodiment of a rotary joint. 1... Pre-washing device, 2... Reciprocating shaking conveyor 3
... Disinfectant removal outer cleaning device, 4... Sterile water washing device, 5... Filling device, 6... Capping device, 7... Tunnel, 100... Rotary joint, 101.
... Rotative packing, 102 ... Stop ring, 103 ... Ball bearing, 104 ...
Spacer 105...stop ring, 106...
void. Figure 2 Figure 1

Claims (1)

[Claims] 1. In a sterilized space, PET bottles are preliminarily washed with a sterilizing solution, then filled with the sterilizing solution, placed on a conveyor, and shaken back and forth for a required period of time to sterilize them; Remove the sterilizing solution by inverting the bottle, then wash the outside of the bottle, wash the inside of the bottle with sterile water to rinse off the sterilizing solution, then fill with the filling solution and cover with the sterile cap. An aseptic filling method for PET bottles characterized by a capping process. 2. A pre-washing device 1 that pre-washes PET bottles and fills them with a sterilizing solution, a plurality of reciprocating shaking conveyors 2 connected to this device and moving in mutually opposite directions, and a device connected to the conveyor that overturns the PET bottles. a sterilizer removal outer cleaning device 3 that removes the sterilizing liquid and then cleans the outside of the PET bottle; and a sterile water cleaning device 4 that is disposed next to the cleaning device and that cleans the inside of the PET bottle with sterile water. It consists of a filling device 5 connected to this cleaning device, and a capping device 6 for capping, and each device is connected by a conveyor, and sterilized gas is supplied to each device and the conveyor. An aseptic filling device for PET bottles consisting of a tunnel 7. 3. In the sterile water cleaning device 4, the rotary joint 100, which rotates while sending sterile water into the plastic bottle, has a stop ring 102 that fixes the rotative packing 101, and a stop that fixes the ball bearing 103 by holding the spacer 104 between them. 3. The filling device according to claim 2, wherein the gap 106 between the rings 105 is filled with a sterilizing liquid or sterile water to form a barrier to prevent bacteria from entering, thereby maintaining the gap 106 in a sterile state.