Food grade nitrogen is an inert gas that meets the standards for use in the food industry. Currently, the EU (E941), US FDA, and China GB standards have strict safety specifications for food grade nitrogen. Taking the EU standard as an example, the purity of nitrogen gas needs to reach 99.9%, the remaining oxygen content is less than 1%, and it does not contain impurities that are harmful to human body.
Its main characteristics include:
Chemically inert: does not react with food components, avoiding contamination of food during production and packaging.
Colorless and odorless: retains the flavor of food to the greatest extent possible
Non-flammable and non-toxic: safe and reliable to use.
Can be used in combination with carbon dioxide and other gases: to form an ideal gas-conditioned environment.
Modified Atmosphere Packaging (MAP) is a kind of freshness preservation technology widely used in the field of food packaging at present, and the principle of MAP is to replace the air (mainly oxygen) in the bag and inject one or more gas mixtures (such as nitrogen, carbon dioxide, etc.) to prolong the freshness period of the food and inhibit the growth of microorganisms.
The core role of nitrogen in this includes:
Displacing oxygen and inhibiting oxidation reaction
Oxygen is one of the main factors leading to the corruption of food, it will trigger the oxidation of oils and fats in the food, vitamin degradation and other reactions, so that the color, smell and taste of food changes, and the nutritional value is also reduced.
Preventing the growth of microorganisms
Many bacteria and molds need an oxygen environment to grow. Nitrogen-filled packaging reduces the oxygen content, making it difficult for these oxygen-demanding microorganisms to survive. Taking fresh fruits and vegetables as an example, in a nitrogen environment, the respiration of fruits and vegetables will be slowed down, reducing their metabolic rate, thus extending the freshness period.
Maintaining Package Shape and Cushioning Protection
For puffed food, cookies and other brittle food, nitrogen filling can prevent the package from deformation under pressure, while playing a buffering role in transportation to reduce the breakage rate.
Compared with traditional preservation methods (such as additives, vacuum packaging, etc.), nitrogen packaging has the following significant advantages for enterprises:
Nitrogen packaging can extend the shelf life of certain food products by several times, which is conducive to long-distance transportation and export business.
Unlike the addition of chemical preservatives, nitrogen does not change the flavor or texture of the food itself, which is more suitable for the current consumer trend of pursuing “zero-added”.
Reduce product loss and return
Effectively reduce returns or recalls due to mold, oxidative deterioration, packaging bulging, etc., saving operating costs.
Enhance brand image
“Nitrogen preservation” can be used as a brand selling point on the packaging, catering to consumers who are concerned about healthy and natural food.
Nitrogen has a wide range of applications, covering almost all packaged foods and raw material storage:
Puffed food (e.g. potato chips, cornflakes)
Nitrogen filling maintains the crunchy texture and avoids moisture and crushing.
Bakery (cookies, cakes)
Retards fatty acid degradation and maintains flavor and crunchy texture.
Coffee beans and powder
Oxygen removal prevents flavor loss and guarantees long-term freshness.
Frozen food, dairy products
Retards microbial growth and prevents quality degradation due to oxidation after thawing.
Alcoholic Beverages (especially Nitrogen Coffee, Nitrogen Beer)
Used for pre-flushing treatment before canning to improve the fineness of bubbles and drinking taste.
Fruits, vegetables and agricultural products storage
Nitrogen is used for bulk nitrogen preservation during storage or transportation to avoid insect infestation and rotting.
Enterprises can choose different nitrogen supply programs according to the scale and demand in actual use, which are mainly divided into the following categories:
Cylinder supply is a common way. Cylinders store the compressed nitrogen in them for easy transportation and use. This method is suitable for food manufacturers with small nitrogen demand. The advantage of this method is that it is flexible and the cylinders can be changed at any time according to the production demand. However, there are some limitations in the supply of cylinders, such as limited storage capacity, the need for frequent replacement of cylinders, which increases the transportation and management costs, and there are some safety risks in the transportation and use of cylinders.
Dewar cylinder supply is suitable for situations where there are special requirements on nitrogen storage temperature. Dewar cylinders can effectively keep liquid nitrogen at a low temperature and minimize the loss of liquid nitrogen by volatilization. For some food production processes that require liquid nitrogen for quick-freezing or low-temperature preservation, Dewar’s cylinders are a good choice. However, the cost of Dewar’s bottle is relatively high, and the storage and use of the environment also has certain requirements.
As the scale of food production continues to expand, on-site nitrogen generation has become a more advantageous option for food manufacturers who use large quantities of nitrogen. On-site nitrogen generation equipment can utilize the nitrogen in the air and separate it through physical or chemical methods to produce high purity nitrogen. This method has a number of advantages. First, it is cost-effective, eliminating the need to bear the cost of cylinder transportation and leasing, which can save a lot of money in the long run. Secondly, the on-site nitrogen production equipment can adjust the nitrogen output at any time according to the production demand to ensure a stable supply of nitrogen, which is not limited by external supply channels. Furthermore, on-site nitrogen generation equipment has high safety, and the modular and containerized design makes it easy to maintain and reduces the risk of leakage and damage.
FUllcryo, as a supplier of industrial gases with experience in the food industry, is committed to customized evaluations and system design for food manufacturers to ensure safe gas supply and effective cost control. Enterprises should consider the following factors when evaluating nitrogen supply modes:
Daily/hourly nitrogen usage
Requirements for nitrogen purity and pressure
Whether long-term continuous gas supply is required
Site space, budget and operators
Availability of automation integration
