What Gases Are Used in Meat Packaging?

The most commonly used gases in meat packaging are carbon dioxide (CO2), oxygen (O2), nitrogen (N2), and sometimes carbon monoxide (CO). These gases are combined in specific mixtures through a process called Modified Atmosphere Packaging (MAP).

In this guide, we’ll explore how these industrial gases work together to preserve meat while meeting industry standards and consumer expectations. We’ll cover each gas separately and discuss some common mixtures for specific meat products.

Carbon Dioxide (CO2): The Antimicrobial Powerhouse

Carbon dioxide is the most common meat preservation gas, and there are many reasons for this. Most notably, it’s an antimicrobial agent that inhibits the growth of aerobic bacteria and molds.

When CO2 dissolves into the meat’s surface moisture, it forms carbonic acid, which lowers the pH and creates an environment hostile to many spoilage organisms. This significantly extends shelf life compared to conventional packaging methods.

Typically, meat packaging mixtures contain between 20-30% CO2 for effective microbial control. Higher concentrations provide better preservation but can lead to package collapse as the gas dissolves over time.

CO2 is particularly effective against Gram-negative bacteria like Pseudomonas, which are common meat spoilage organisms. These bacteria can cause slime formation and off-odors in improperly packaged meat.

Oxygen (O2): Color Retention and Consumer Appeal

Oxygen plays a crucial but complex role in meat packaging. Its main purpose is maintaining the bright red color consumers associate with freshness.

In fresh red meat packaging, oxygen levels are typically maintained at 70-80% to promote oxymyoglobin formation. This compound gives meat its appealing cherry-red color that shoppers look for when making purchase decisions.

However, oxygen is a double-edged sword. While preserving color, high O2 levels can accelerate lipid oxidation, which leads to rancidity and off-flavors (particularly in fatty meats and ground products).

This is why processors must carefully balance oxygen levels based on:

• Specific meat type
• Fat content
• Expected shelf life.

As a rule of thumb, leaner cuts can typically tolerate higher oxygen levels than fattier products.

Many meat processors use oxygen analyzers to ensure precise gas mixtures during the packaging process. Even small deviations can affect both appearance and shelf life.

Nitrogen (N2): The Inert Filler

Nitrogen is the neutral component in meat packaging gas mixtures. As an inert gas, it displaces oxygen without reacting with the meat product.

The primary function of nitrogen is preventing package collapse when CO2 is absorbed into the meat tissue. It maintains package volume and structural integrity during storage and transportation.

Nitrogen typically comprises 10-20% of standard meat packaging gas mixtures for fresh red meat. For poultry and cooked products, nitrogen percentages can be much higher (up to 75%) since these products don’t require oxygen for color maintenance.

Because nitrogen has no antimicrobial properties of its own, it’s always used in combination with CO2. The two gases work together – CO2 for preservation and N2 for package stability.

For meat processing facilities, nitrogen is a cost-effective component of their gas program. Its wide availability and stability make it ideal for consistent, large-scale operations.

Carbon Monoxide (CO): Controversial But Effective

Carbon monoxide is used in some meat packaging systems, though its application is more limited and regulated than the other gases. CO binds with myoglobin to form carboxymyoglobin, creating a stable red color that persists longer than oxygen-based color preservation.

In the US, the FDA has granted GRAS (Generally Recognized As Safe) status to CO for use in meat packaging at concentrations not exceeding 0.4%. However, the European Union has banned its use entirely.

The controversy surrounding CO stems from concerns that it might mask spoilage by maintaining red color even when meat has begun to deteriorate microbiologically. Critics argue this could potentially mislead consumers.

When used, CO is typically combined with 30% CO2 and around 70% N2. The CO concentration remains very low (0.3-0.5%) but is highly effective at color stabilization.

Many large meat processors have moved away from CO systems due to consumer perception issues, despite scientific evidence supporting its safety when properly used.

Gas Mixtures for Different Meat Products

Different meat products require specific gas mixtures to optimize preservation while maintaining quality, as shown in this table:

Each of these mixtures is a result of years of research and practical application in commercial settings. The science of gas packaging continues to evolve as processors seek the optimal balance between shelf life, appearance, and safety.

MAP Implementation and Technology

Implementing MAP technology requires specialized equipment and precise gas handling systems. The investment delivers significant returns through extended product life and reduced waste.

Modern meat packaging lines use gas flushing systems that remove atmospheric air and replace it with the precise gas mixture. This process happens in seconds to minimize exposure to ambient conditions.

Gas analyzers are critical components in quality control systems because they ensure that each package receives the correct gas composition. Even small variations can affect product shelf life and appearance.

For meat processors, having reliable gas supply systems is essential. Many facilities use bulk gas storage with automatic switchover systems to ensure uninterrupted production.

Packaging materials themselves must have appropriate gas barrier properties to maintain the modified atmosphere throughout the product’s shelf life. High-barrier films prevent oxygen ingress and gas mixture loss.

Preserve Meat Products With the Right Gases

The gases used in meat packaging involve a carefully balanced system that extends shelf life while maintaining quality and safety. CO2, O2, N2, and sometimes CO work together to create optimal conditions for meat preservation.

As consumer demands for freshness, convenience, and reduced food waste continue to grow, gas packaging technology will remain essential to the meat industry. Understanding the specific roles and applications of these gases helps processors optimize their operations and deliver superior products to market.