Gas flushing is one of the procedures in modified atmosphere packaging, which is a type of food packaging. This procedure aims at changing the inside of the packaging that has to store certain types of foods.
The most significant application of this procedure is when it comes to the packaging of foods that must be preserved. Gas flushing may help keep those products fresh for longer durations.
What is the gas flushing?
The process of injecting and then sucking out inert gases repeatedly to remove oxygen from food packaging is known as gas flushing. The primary purpose of this procedure is to enhance the shelf life of a food product.
Modified atmosphere packaging
The processing of altering the atmosphere inside the packaging to help preserve foods is known as modified atmosphere packaging, also called MAP. The ultimate goal of this method is to enhance the shelf life of a food product.
MAP applications, particularly gas flushing, may be mandatory during the packaging of fish, poultry, and other perishable foods.
When to use gas flushing?
The purpose of using gas flushing is to reduce the amount of oxygen in the packaging to 3%, or maybe even less. The gases used in this process are denser than oxygen. Those gases, when flushed into the packaging, push the oxygen. Repeated flushing of gas eliminates oxygen.
Benefits of gas flushing include protection against discoloring, an added layer of packaging, and increased shelf life. The injected gas also serves as a buffer for the contents inside the packaging. The gas prevents contents packed inside the packaging from coming in contact with each other.
In most of the gas flushing applications, gas formulations must be highly precise. For instance, you will need carbon dioxide, carbon monoxide, and nitrogen in a very calculated proportion to preserve meat.
Nitrogen surrounds the contents in a package, preventing them from getting damaged. Carbon dioxide is an antimicrobial agent. Carbon monoxide is a stabilizer.
Gases used for gas flushing
The most commonly used gases for the gas flushing process include argon, nitrogen, and carbon dioxide.
The function of argon is the same as that of nitrogen. The primary purpose of this gas is to inhibit enzymes, chemical reactions, and mold. This gas is best suitable in case when nitrogen is not an option.
Nitrogen, or N2, is used to remove air and oxygen from the inside of a package. This gas is used in most of the MAP applications. Due to its higher density, nitrogen also prevents oxygen buildup inside a package.
The gas that can prevent the growth of bacteria and several forms of mold is carbon dioxide. This gas enhances the shelf life of a food product drastically.
Carbon dioxide can get absorbed in fats and water. Packaging companies pay special attention to the amount of carbon dioxide to use in the food packaging, as it can alter the flavor and color of food. They make sure that the amount of carbon dioxide they use is significant enough to extend the shelf life, but it is not too much to cause alteration in the color and flavor of food.