JPH068921A - Method and apparatus for measuring air content in air-containing hermetic package - Google Patents

Abstract

PURPOSE:To calculate easily the volume of gaseous body in an air-containing hermetic package that contains contents and the gaseous body by a method wherein the package is cooled down or heated up and after that, an area at the temperature in a specified range of values on the surface of the package is detected. CONSTITUTION:An air-containing hermetic package A obtained by packing contents such as curry into a retort pouch together with gaseous body is conveyed, being laid down on a conveyer 101, and cold air is blown during the conveyance onto the package by a cold-air-supplying device 103, and thereby temperature difference is made discernible on the package A between a part contacting the gaseous body and a part contacting the contents. Then, the temperature over the surface of the package A is detected by a detector 211 utilizing infrared rays, and the obtained temperature information is converted into thermal image data by means of a conversion circuit 20, and is stored in a storage section 30. The area at the temperature in a specified range of values on the surface of the package A is detected from the thermal image data in the storage section 30 by a detecting means 40, and the volume of the gaseous body in the package A is calculated by a calculation circuit 50 out of the detected area, and is displayed on a display unit 60.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring the air content of an airtight sealed soft package.

[0002]

2. Description of the Related Art Recently, liquid foods such as curry and stew are filled and sealed in a retort pouch together with air, a gas such as an inert gas, and then while rotating the retort pouch,
A technique for sterilizing under pressure (hereinafter referred to as a rotary retort sterilization technique) is drawing attention.

As a result of research on the rotary retort sterilization technique, the inventors of the present invention have found that in the technique, it is necessary to set the air content of the retort pouch within a predetermined range, for example, 2 to 50% by volume in terms of sterilization efficiency and the like. In addition, when treating many retort pouches at once, not only is the air content of each retort pouch in the above specified range,
It is effective to make the variation of the air content between the retort pouches within a certain range, for example, -3 to + 10% with respect to the set air content, in order to effectively improve the quality due to heat sterilization unevenness and overheating. We have found that it is extremely important in terms of prevention and shortening of heat sterilization time.

However, since the retort pouch is made of a flexible film, it is difficult to adjust the air content as compared with a rigid or semi-rigid container such as a cup or tray. Nevertheless, conventionally, no technique for measuring the air content of the retort pouch has been found.
This seems to be one of the main causes of the fact that the above-mentioned rotary retort sterilization technique has not been widely used until now. The present invention has been made in view of these circumstances.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for measuring the air content of an airtight sealed package.

[0006]

The first aspect of the present invention is as follows.
The air-containing hermetically-sealed package having a filling and a gas is subjected to a cooling treatment or a heating treatment, and at the same time as or after the treatment, the area of a predetermined temperature range portion of the surface of the air-sealed hermetically-sealed package is detected and obtained. A method for measuring the air content of an airtight sealed package, comprising calculating the volume of gas in the airtight sealed package from the area. A second aspect of the present invention is: (a) a means for subjecting an airtight sealed package having a filling and a gas to a cooling treatment or a heat treatment, and (b) a portion of the surface of the airtight sealed package in a predetermined temperature range. An apparatus for measuring an air content of an airtight sealed package, comprising: a detection unit that detects an area; and (c) a circuit that calculates the volume of gas in the airtight sealed package from the area obtained by the detection unit.

[0007]

According to the present invention, the area of a portion of the surface of an airtight hermetically sealed package containing a filler and gas in a predetermined temperature range is detected, and the gas in the airtight hermetically sealed package is detected from the obtained area. The volume can be calculated.

An embodiment of the present invention will be described in detail below with reference to the drawings. As shown in FIG. 1, a device 1 for measuring the air content of an airtight sealed package is obtained by filling a retort pouch with a filling such as curry or stew together with a gas such as air or an inert gas. It has a conveyor (conveyance path) 101 for conveying the airtight sealed package in a lying state. When the conveyor 101 conveys a standing pouch such as a standing pouch having different thicknesses at the upper end portion and the lower end portion as an airtight sealed package, the upper surface of the standing pouch in a lying state is substantially horizontal, Inclination is desirable. In addition, it is possible to make the standing pouch and the like always hold a constant shape, to stabilize the position of the gas in each air-sealed sealed package without variation, and to ensure the volume of gas in the air-sealed sealed package more reliably. It is desirable because it can be measured. As such a means, it is desirable to arrange a form (not shown) on the conveyor 101, which has an ideal bottom surface shape and side surface shape of the standing pouch. Further, for the same reason, a pressure roller (not shown) may be provided above any position of the first conveyor up to a detector described later. It is desirable that the pressure roller has a rotation shaft supported so as to be movable in the vertical direction in order to effectively prevent the retort pouch from being broken by the pressure of the pressure roller. Further, instead of the pressure roller, a means for pressurizing the retort pouch in a laid state by vertically moving a flat plate or an outer peripheral portion of the retort pouch in a laid state by vertically moving a concave pressure surface is added. A means for pressurizing may be adopted, but the last means is most preferable in that the gas in the retort pouch is stably held at a predetermined position.

A cold air supply device (cooling means) 103 is arranged in the middle of the convey path of the conveyor 101. As a result, a portion of the surface of the airtight hermetically sealed package which is in contact with the gas in the airtight hermetically sealed package (hereinafter referred to as a portion of the surface of the airtight hermetically sealed package which is in contact with the gas) and the airtight seal of the surface of the airtight hermetically sealed package. It is possible to make clear the temperature difference between the part in contact with the filling in the package (hereinafter referred to as the part in contact with the filling on the surface of the airtight sealed package). The use of the cooling means is particularly effective when the filling is a high temperature one such as curry or stew immediately after being cooked. As a cooling means,
Instead of the cold air supply device, a cold water supply device that sprays cold water into the air-containing sealed package in a shower or spray form, or a cold water tank in which the air-containing sealed package is immersed in cold water can be adopted. Further, instead of the cooling means, a heating means can be adopted. The adoption of heating means is particularly effective when the filling material has a low temperature. As the heating means, a hot air supply device for blowing hot air onto the air-containing sealed package, a hot water supply device for pouring hot water into the air-containing sealed package in a shower or spray form, or an air-containing sealed package There is a hot water tank etc. that is immersed in hot water.

In the vicinity of the cold air supply device 103 on the way of the conveyor (conveying path) 101, upwardly, the surface of the airtight sealed package A by infrared rays emitted from the airtight sealed package A on the conveyor 101. 2 to detect the temperature of
11 are arranged. The detector 211 includes a circuit 20 for converting the obtained temperature information into thermal image data, a storage unit 30 for storing the thermal image data, and a predetermined temperature range on the surface of the airtight sealed package from the thermal image data in the storage unit 30. Detecting means 40 for detecting the area of the portion, calculating circuit 50 for calculating the volume of gas in the air-sealed sealed package from the area obtained by the detecting means 40, and display section 60 for displaying the value obtained by the calculating circuit 50. Are connected to.

In the apparatus 1 for measuring the air content of an airtight sealed package having the above structure, first, the airtight sealed package A is conveyed by the conveyor 101. When the air-containing sealed package A reaches the position of the cold air supply device 103, the air-containing sealed package is cooled by the cold air supply device 103. As a result, FIG.
It is possible to clarify the temperature difference between the portion B on the surface of the airtight hermetically sealed package body in contact with the gas a and the portion C on the surface of the airtight hermetically sealed package body in contact with the filling b shown in FIG. An example of the cold air condition is −30 to 30 ° C. Simultaneously with or immediately after the cooling process, the detector 211 is connected to the conveyor 101.
The temperature of the surface of the airtight sealed package A is detected by the infrared rays emitted from the above airtight sealed package A. The obtained temperature information is converted into thermal image data by the circuit 20 for converting into thermal image data, and stored in the storage unit 30. Then, the detection unit 40 detects the area of the portion of the surface of the airtight sealed package in the predetermined temperature range, that is, the area of the portion B in contact with the gas on the surface of the airtight sealed package, based on the thermal image data ( Note that the above-mentioned predetermined temperature range is specifically 30 to 50 ° C when the temperature of the filling material is 70 ° C, for example). Subsequently, the calculation circuit 50 calculates the volume of gas in the airtight sealed package from the above area. In the airtight sealed package, the area of the portion of the surface of the airtight sealed package that is in contact with gas is
It has a correlation with the volume of gas in the airtight sealed package. Therefore, based on the above correlation, the volume of gas in the airtight sealed package can be calculated from the area of the portion of the surface of the airtight sealed package that is in contact with gas. The specific correlation between the area of the gas-containing hermetically sealed package surface in contact with the gas and the volume of gas in the gas-containing hermetically sealed package is determined in advance in the gas-containing hermetically sealed package. This can be easily known by changing only the volume of gas variously and examining how the area of the surface of the airtight sealed package which is in contact with gas changes. Next, the value calculated by the calculation circuit 50 is displayed on the display unit 60.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an apparatus for measuring an air content of an airtight sealed package according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of an airtight sealed package.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Measuring device for air content of airtight sealed package 20 Circuit for converting temperature information into thermal image data 30 Storage section for storing thermal image data 40 Detecting means 50 Calculation circuit 60 Display section 101 Conveyor 211 Detector

Claims (2)

[Claims] 1. An airtight sealed package having a filling and a gas is subjected to a cooling treatment or a heating treatment, and at the same time as or after the treatment, the area of a portion of the surface of the airtight sealed package in a predetermined temperature range is detected. Then, the volume of gas in the airtight sealed package is calculated from the obtained area, and the method for measuring the air content of the airtight sealed package. 2. A means for subjecting an airtight sealed package having a filling and a gas to a cooling treatment or a heat treatment, and (b) detecting the area of a portion of the surface of the airtight sealed package in a predetermined temperature range. A device for measuring an air content of an airtight sealed package, comprising: a detection unit; and (c) a circuit for calculating the volume of the airtight sealed package in gas from the area obtained by the detection unit.