Meat products discussed in this article refers to cooked meat products such as sausage, ham, bacon, stewed meat and smoked meat, etc. In order to extend the shelf life of the meat products, the manufacturers usually use vacuum packaging.

Vacuum packing is a method of packaging that removes air from the package prior to sealing. This method involves (manually or automatically) placing items in a plastic film package, removing air from inside, and sealing the package. Shrink film is sometimes used to have a tight fit to the contents. The intent of vacuum packing is usually to remove oxygen from the container to extend the shelf life of foods and, with flexible package forms, to reduce the volume of the contents and package. Vacuum packing reduces atmospheric oxygen, limiting the growth of aerobic bacteria or fungi, and preventing the evaporation of volatile components.

Therefore, it can be easily understood that how to limit the oxygen content inside the vacuum packaging is critical to the product quality of meat products. This article provides a simplified residual oxygen test method for vacuum packaging used for meat products for your reference.

Figure 1. Vacuum Packaging for Meat Products

Currently there is no uniform standards for residual oxygen in vacuum packaging. The testing instrument we used is Labthink’s C650B Headspace Gas Analyzer. The vacuum test cell is composed of an outer chamber and an inner chamber. Before the test, the inner chamber, where the test specimen is placed, is completely filled with water and sealed with the sealing plate. The outer chamber, which is also the measuring chamber, is slowly injected with water to a designated level and sealed. Both chambers are thereafter evacuated until the test specimen expands. The residual oxygen within the specimen is obtained by fluid level analysis technique associated with corresponding calculations.

The specimens are provided by one meat product manufacturer. The tests can be performed according to the following procedures.

(1)  Submerge the specimen into the vacuum chamber and fill the vacuum chamber with water. Then close the sealing plate. Inject water to a designated level and close the cap.

(2)  Set pressure.

(3)  Turn on the vacuum pump and start to evacuate the vacuum chamber. Due to the pressure difference between the inside and outside of the specimen, the specimen will expand until the preset pressure is reached.

(4)  The system will calculate the volume of residual oxygen inside the vacuum packaging according to the measured data and display the final test results.

For more details about C650B Headspace Gas Analyzer, please visit www.labthink.com

About Labthink Instruments Co., Ltd:

Labthink Instruments Co., Ltd is one leading supplier of packaging testing instruments, which is headquartered in Jinan, China and operated in Boston, U.S.A.