Potato Chip Bags Quality Testing

It happened to all of us. You pay $4.00 or more for a bag of chips, pull apart the bag, and are forced to look deep inside for your tasty treasure. Instead of filling up the entire bag, the chips are lying innocently at the bottom and the rest of your bag was air…or was it?

Foods such as chips need a cushion to ensure they’re whole and crispy when you buy them. But pumping the bag full of air won’t work. Why? When processed foods such as chips are exposed to oxygen, the food breaks down and becomes rancid.

That’s why nitrogen is used. “Nitrogen flushing” is a process whereby all the air is removed from the bag and replaced with nitrogen gas. The nitrogen doesn’t affect the taste of the food and doesn’t react with it like oxygen does, so the food stays fresher longer. And, since the nitrogen gas fills up the bag, the contents inside are protected during shipping.

Therefore, when you involve in potato chip bags quality testing, you must consider the property of potato chip bags as below:

u  Good barrier property to Nitrogen

u  Proper seal strength for high pressure inside the bags

u  Bag integrity to prevent oxidation

To improve your potato chip bags, the first step is to know the current property of your potato chip bags. And then evaluate what is necessary you need.

Barrier Property to Nitrogen

Potato chip bags are likely made of laminated films because of their low gas permeability to nitrogen. Basically, the gas transmission rate of potato chip bags are lower than 0.1 cm³/m²·24h. When you measure the gas permeability of potato chip bags, you need choose a precise and high accuracy testing instrument in this test range, such as VAC-V2 Gas Permeability Tester from Labthink. VAC-V2 is based on differential pressure method and with test range 0.05~50,000 cm³/m²·24h·0.1MPa, which is totally applicable to potato chip bags gas permeability test. VAC-V2 is a use-friendly and easy-operated instrument.

1.      Just mount the specimen in the gas diffusion cell, the test chamber is divided into a upper chamber and lower chamber by the specimen.  

2.      Evacuate the testing Chamber

3.      Flush the upper chamber using high purity nitrogen and make the test chamber has a constant pressure difference between upper chamber and lower chamber

4.      The Nitrogen will permeate through the specimen into low chamber because of the pressure difference

5.      Gas permeability and other barrier properties of the specimen can be obtained by monitoring the pressure changes in the lower chamber

This Instrument is controlled by computer and equipped with professional software. All the test process is intelligent and automatic computer. Test results can be displayed on the computer screen directly.

Integrity and Seal Strength Test

Actually, there is an instrument can measure potato chip bag integrity as well as seal strength test. LSSD-01 Leak and Seal Strength Tester combines seal strength test and package integrity test in one instrument. It can be used to conduct burst testing, creep testing and creep to failure test.

Burst Testing

Burst testing determines the overall minimum seal strength of the bag seals by inflating the bag at a uniform rate until the seal separates at the point of greatest weakness. The burst test is a peak inflation pressure test; you can see how the pressure increases to a maximum pressure at which the pressure drops to zero. This drop represents the rupture of the seal. The pressure at which the pouch bursts is a variable statistic that can be utilized to document process development and process control through the use of tools such as upper and lower control limits, such as those seen on this control chart segment.

Creep Testing

The Creep Test is a second general type of whole package inflation seal strength test. In the Creep Test, a filled, sealed package is inflated to a constant pressure, which is then held for a specified time, resulting in a pass/fail result. This provides a test for slow shear of the adhesive bond similar to a dead weight hanging on the seal. A suggested starting pressure for peelable seals is to begin evaluating your seal with a creep pressure that is about 80% of the burst value. The inflation rate is not critical, as long as the initial fill is not so fast as to shock the seal or so slow as to result in an overly long test time. The shortcomings of this test are the need for the operator to visually examine the seal at the end of the test to determine the degree of seal peel, and the lack of a variable statistic upon which to perform process control analysis.

For more potato chip bags quality testing, please contact Yarina Gao via trade5@labthink.cn  or visit our website www.labthinkinternational.com.cn