Comparison of Barrier Properties of Aluminized Composite Film for Instant Noodle Packaging

1、Significance
Instant noodles are usually made by deep frying. They have a high content of grease and a low moisture. Therefore, in order to prevent the oxidation and deterioration of oil, the generation of harmful substances, stale flavor due to contact with oxygen or light during the storage of instant noodles, or the appearance of crispness, mildew and other phenomena due to contact with moisture absorption, the packaging of instant noodles should have good barrier properties.

The aluminum coating composite film has high light shielding and barrier, and the packaging cost is relatively low, so it is widely used in the packaging of instant noodles. However, due to the influence of factors such as aluminum coating process and substrate material, the barrier performance of aluminum coated composite film is not the same. In this paper, the oxygen barrier properties of aluminum coated composite film produced by different manufacturers is compared.

2、Test sample
In this test, three kinds of aluminized composite films for instant noodle packaging are used as test samples to test the oxygen permeability.
3、Standard

In this paper, the principle of coulometer is used to test the samples. The test process is in accordance with ASTMD 3985 – 95 Standard Test Method forOxygen Gas Transmission Rate through Plastic Film andSheeting Using a Coulometric Sensor.

4、Test instrument
In this test, C230HOxygen Transmission Rate Test System is used to test the oxygen transmission rate of the sample. The instrument is independently developed and produced by Jinan Labthink Instruments Co., Ltd.

4.1 Test principle
Coulometric method is a test method using Coulometric sensor, which is also called equal pressure method because the gas pressure on both sides of the sample is equal during the test. The upper and lower test chambers of the instrument are separated by the clamped sample. The upper chamber is filled with oxygen of certain pressure, and the lower chamber is filled with high-purity nitrogen of equal pressure. Under the effect of concentration difference, oxygen penetrates into the lower chamber from the upper chamber through the sample, and is carried to the sensor by nitrogen in the lower chamber for analysis. Coulometric sensor is developed based on the principle that oxygen can generate quantitative electrical signal when participating in electrochemical reaction. By measuring the electrical signal, the oxygen amount penetrating into nitrogen side can be obtained, and the oxygen volume penetrating through unit area sample in unit time can be calculated accordingly.

5、Test process
(1) Use a sampler to cut one specimen from each of the three sample surfaces.
(2) The three specimens are sealed and clamped in three test chambers of the instrument, and clamped with the test chamber cover.
(3) In the control software of the instrument, set the sample name, sample thickness, test temperature, humidity, test mode and other parameter information, and click the test button to start the test. The instrument is tested according to the set parameters, and the test results are displayed after the test.

6、Test result
The device showed that the oxygen permeability of the three samples were 1.689 cm3/(m2•day),12.934 cm3/(m2•day) and 41.071cm3/(m2•day)respectively.

7、Conclusion
The oxygen permeability of aluminized composite film material is an important factor affecting the quality of packaged instant noodles in storage period. In this paper, we use C230H Oxygen Transmission Rate Test Systemto test the oxygen permeability of three kinds of aluminum coated composite film samples for instant noodle packaging. One test has completed the test of three kinds of samples. The test efficiency is high, the control of each parameter in the test process is stable and accurate, which ensures the reliability of the test results, and the accuracy of the test results is high. It can be seen from the test results that the oxygen permeability of the three samples is quite different, that is to say, there is a big difference in the oxygen barrier. This difference is mainly related to the thickness, density and other factors of the aluminized layer. Therefore, not all the aluminized composite films have a high barrier ability, so it is necessary to strengthen the barrier test of this kind of materials.

Jinan Labthink Instruments Co., Ltd, is dedicated to providing customers with packaging testing solutions and helping the manufacturers to reach their goals of quality and safety assurance through improvement of packaging testing techniques and development of high-end packaging testing instruments. The newly introduced C series barrier testing systemsadopting self-sensing technology revolutionarily improved the testing accuracy, efficiency and automation, realized the paradigm shift of packaging barrier testing instruments. For more information please visit www.labthink.com