High-purity nitrogen: Nitrogen with a purity of 99.9% ~ 99.999% is commonly used in food production. It features extremely low oxygen content, which isolates oxygen to restrain oxidation and mildew growth.

Low dew point: The dew point is ≤ -40 ℃, and premium models can reach -60 ℃ ~ -70 ℃, indicating an extremely low water content in nitrogen. This eliminates food dampening, caking and microbial reproduction caused by water vapor. Conventional nitrogen generators deliver nitrogen with high dew points and high moisture content, making them unsuitable for food products requiring strict moisture control, such as baked goods, puffed snacks, freeze-dried food and fried food. Dry nitrogen with a low dew point is critical for food preservation.

Core Application Scenarios in the Food Industry

1. Modified Atmosphere Packaging of Food Products (Most Widely Used)

Applicable Products

Potato chips, biscuits, puffed food, pastries, cakes, nuts, roasted seeds and nuts, frozen dough products, fresh meat, cooked marinated food, instant food and tea.

Working Principle

Nitrogen displaces the air inside packaging bags and reduces oxygen content to below 1%, which inhibits lipid rancidity, pigment fading and flavor loss. Dry nitrogen with low dew point contains no moisture, preventing condensation on the inner wall of packages and stopping nuts and biscuits from absorbing moisture, turning soft and going moldy. Nitrogen supports packaging bags to avoid crushing and breakage, extending the shelf life by 2 to 6 times.

Process Requirements

• Puffed food & nuts: Nitrogen purity ≥99.9%, dew point ≤-50℃
• Fresh chilled meat packaging: High-purity nitrogen of 99.99% with low dew point to reduce the reproduction of anaerobic bacteria

2. Storage and Transportation of Grain, Oil and Edible Oil

Applicable Oils

Soybean oil, peanut oil, rapeseed oil, palm oil, nut oil and rice bran oil

Oils are highly susceptible to oxidative rancidity when exposed to oxygen, generating harmful substances.

• Nitrogen blanketing for oil tanks: Dry low-dew-point nitrogen fills the headspace of oil tanks to isolate air and prevent oil oxidation.
• Full-process nitrogen blanketing during refining and filling: High-purity dry nitrogen is continuously fed into conveying pipelines and temporary storage tanks to maintain an oxygen-free and moisture-free environment throughout the process.
• Grain storage: Nitrogen filling in silos for rice, wheat and miscellaneous grains kills pests and suppresses bacteria. Low-dew-point nitrogen does not raise grain moisture content, avoiding mildew and agglomeration.

3. Production of Baked Goods, Pastries, Chocolate and Confectionery

• Chocolate processing: Nitrogen blanketing for mixing and holding tanks of molten chocolate prevents lipid oxidation that causes whitening and loss of gloss; low-dew-point nitrogen avoids bloom on chocolate induced by water vapor.
• Cream, fillings and jams: Nitrogen protection for filling mixing barrels slows down oxidation and discoloration of fruit acids.
• Crisp cakes, peach cakes and mooncakes: Nitrogen filling on cooling and packaging lines prevents moisture absorption and lipid rancidity.

4. Freeze-Dried Food, Crispy Fruits & Vegetables and Dehydrated Dry Goods

Freeze-dried fruits, freeze-dried meat, dried shiitake mushrooms and dried vegetables have extremely low moisture content and easily reabsorb moisture upon exposure to trace water vapor. High-purity low-dew-point nitrogen is continuously purged at the discharge and packaging stations of freeze-drying chambers. It isolates air and water vapor to retain crispy texture, extend shelf life and reduce the use of preservatives.

5. Preservation of Meat and Aquatic Products (Chilled / Frozen)

Chilled steak, pork belly, fish fillets, shrimp and prepared dishes

• Modified Atmosphere Packaging (MAP): Nitrogen as the main component mixed with a small amount of carbon dioxide to inhibit bacterial growth.
• Low-dew-point nitrogen avoids water droplets forming inside packages, preventing meat from turning pale and sticky.
• Nitrogen purging for turnover boxes in frozen warehouses stops aquatic products from weeping and turning black due to oxidation after thawing.

6. Alcoholic Beverages, Drinks and Brewing Industry

Red wine, beer, fruit juice, liquor and fermented beverages

• Nitrogen blanketing for wine tanks: Nitrogen fills storage tanks post-fermentation to isolate oxygen and prevent wine from developing off-flavors and darkening in color via oxidation.
• Backpressure nitrogen for filling lines: Dry low-dew-point nitrogen displaces air inside bottles without introducing moisture, ensuring stable taste.
• Nitrogen protection for fruit juice and fruit vinegar production lines delays enzymatic browning of fruit pulp.

7. Tea, Chinese Medicinal Herbs and Dried Specialty Products

Green tea, black tea, wolfberries, ginseng and dried mushrooms Storage and vacuum nitrogen packaging with high-purity low-dew-point nitrogen. It isolates oxygen to prevent tea polyphenols from oxidizing and turning yellow, as well as flavor volatilization. Nitrogen with ultra-low moisture content will not soften dried goods by absorbing moisture.

8. Protection of Powdered Food Raw Materials (Milk Powder, Protein Powder, Starch, Flavors)

Milk powder, non-dairy creamer, protein powder and spice powder readily absorb moisture to cake and deteriorate via oxidation.

• Nitrogen blanketing for silos and mixers
• Nitrogen purging for powder conveying pipelines

Low-dew-point nitrogen prevents powder from agglomerating due to water absorption, maintains good flowability and extends the storage life of raw materials.

9. Explosion Prevention and Inert Atmosphere Protection in Food Processing

Dust from flour, starch, powdered sugar and milk powder is flammable and explosive. High-purity nitrogen is injected into workshops and silos to lower oxygen concentration and meet inerting standards for explosion protection. Low-dew-point nitrogen will not increase dust humidity or interfere with production processes.