Nitrogen gas preservation techniques

Nitrogen gas

Nowadays, there has been more and more research on how to use different gases in the packaging process of food products. To help maintain the quality and nutritional value of food products as long as possible. which increases the shelf life of the food itself. Gas-Flushing is the process of filling products under the atmosphere of a specific gas, such as carbon dioxide. or nitrogen gas By spraying the desired gas to replace the air inside the container. which is one of the most widely used methods especially used for Remove oxygen gas in containers of products sensitive to oxidation (Oxidation Reaction) such as fatty foods, fruit juices, etc.

The gas used to replace the air inside the container can be of many types, such as Carbon Dioxide (CO2), Nitrogen (N2), Oxygen (O2), etc. But the most commonly used gas in the Gas Flushing system in the food industry is Nitrogen gas because it is a gas that has the following properties:

It is a colorless, odorless, tasteless and non-toxic gas. Therefore, it can be used with all kinds of food products.

It is an inert gas to chemical reactions. Therefore, it is often used to replace oxygen gas. to prevent the oxidation of fats and oils or browning reaction in food

It is a non-explosive gas. and safe for the environment

It is a gas that is very soluble in water and fat. Therefore, nitrogen gas bubbles can be sprayed through to the raw material. or liquid products such as oil

The nitrogen gas will encapsulate the oil molecules. This makes it possible to reduce oxidation reactions. and rancidity Nitrogen gas is injected to remove air in the containers of food products such as potato chips and snacks. It is one step that allows manufacturers to extend the shelf life of their products. longer

Benefits of packing food products using the Gas-Flushing method

1. To increase the shelf life, delay or prevent the deterioration of the quality of food products. The major chemical reactions that occur in food products are oxidation reaction which when it occurs with fat or oil will cause the food to go rancid a change in color smell and taste of food Therefore, using a gas flushing process to remove the oxygen gas in the air that surrounds the food.  packed in different atmospheric conditions as shown in Table 1.

Table 1 Comparison of shelf life of potato chips packed under different atmospheric conditions

Storage conditions The amount of oxygen gas remaining in the container shelf life

Normal atmospheric conditions 21.0% 6 weeks

Conditions in which nitrogen gas is injected into the container 2.0% 12 weeks

1.5% 16 weeks

1.0% 20 weeks

0.5% 24 weeks

From the table it can be seen that Potato chips packed in containers with nitrogen gas sprayed instead. Until the oxygen content in the container is only 0.5%, the shelf life of potato chips can be extended longer than stored chips. maintained in normal atmospheric conditions up to 4 times

2. Reduce the use of food additives (Food) Usually in food products with a high content of fat, such as potato chips, food additives such as BHA and BHT are added to help prevent oxidation. (Antioxidants), but when nitrogen gas is added to replace normal air. Nitrogen gas prevents the transformation of fats and oils used in production process by reducing the oxidation reaction Therefore, it can help reduce the use of food additives in another way.

3. Prevent damage that may occur to the product inside the container in addition to the benefits mentioned. The packing technique is designed to form a pillow-shaped container. And when gas is added to replace the air in the container, the bag inflates. It helps to improve the appearance of the container to be more eye-catching. It can also help prevent damage to internal products. containers as well, such as breakage of potato chips, etc.

Factors affecting the use of gas for packaging food products

Only relying on the gas injection method to replace it cannot help. maximum efficiency There are still other factors that must be considered and used together, such as the properties of the film used as a container It should have gas permeability protection properties. especially oxygen gas This is a very important factor for the shelf life. Therefore, using the method of spraying gas to replace together with the use of containers which can prevent gas permeability well It can help preserve the amount of nitrogen gas added to the container. At the same time, it can also prevent moisture penetration. And oxygen gas from outside is not allowed to penetrate into the container as well.

There are also other factors Other considerations include storage conditions such as temperature, light and humidity control, microbial count and status. (Microbiological State) contained in that food product. Suitable gas type and concentration for each food product packaging. and equipment used in packing

Information: Post-harvest Technology Innovation Center