Is All CO2 Food Grade?

No, not all carbon dioxide (CO2) is food grade. CO2 must meet specific purity and quality standards to be considered food grade and safe for consumption in food and beverage applications. 

In this guide, we’ll explore the key differences between food-grade and industrial CO2, regulatory requirements. You’ll also learn why using the right grade matters for your specific application from the safety perspective.

What Makes CO2 Food Grade?

Food-grade CO2 generally has a minimum purity level between 99.8-99.9%, depending on specific regulatory standards and applications, with strict limitations on allowable impurities. This high level of purity is essential for ensuring safety in food and beverage applications.

Industrial-grade CO2, on the other hand, typically has a lower purity level (ranging from 90-99% depending on the specific application) and may contain contaminants that aren’t acceptable for food use, such as: 

• Benzene
• Sulfur compounds
• Ammonia

The source of CO2 plays a significant role in determining its grade. Food-grade CO2 commonly comes from fermentation processes like beer or ethanol production, which naturally produce purer CO2. Some is also derived from natural wells or as a byproduct of ammonia production, followed by extensive purification.

In fact, the bubbles in your favorite beer and the CO2 used to carbonate your soft drinks might come from the same production process!

Regulatory Standards for Food-Grade CO2

The FDA recognizes carbon dioxide as Generally Recognized as Safe (GRAS) when it meets specific purity standards. According to FDA regulations, food-grade CO2 must comply with the specifications outlined in 21 CFR §184.1240.

In addition to FDA guidelines, the International Society of Beverage Technologists (ISBT) has established even more stringent quality guidelines for beverage-grade CO2. Their Quality Verification Level (QVL) standards specify maximum allowable levels for over 30 potential impurities.

European standards are governed by the European Industrial Gases Association (EIGA), which sets comparable requirements for food-grade CO2 purity and handling procedures.

Companies that produce or distribute food-grade CO2 must maintain detailed documentation of testing and quality control procedures. Each batch should come with a Certificate of Analysis (COA) verifying its compliance with applicable standards.

Applications for Food-Grade CO2

Beverage Carbonation

Food-grade CO2 is essential for adding bubbles to sodas, sparkling water, beer, and other carbonated beverages. The purity of the CO2 directly impacts the taste and safety of these products.

Even trace impurities can affect flavor profiles or introduce off-tastes in beverages. This is why beverage manufacturers typically require CO2 that meets or exceeds ISBT standards.

Food Preservation and Packaging

Carbon dioxide plays a crucial role in modified atmosphere packaging (MAP), where it helps extend the shelf life of fresh and processed foods. When used in packaging, CO2 inhibits bacterial growth and slows oxidation.

Food manufacturers use CO2 for everything from meat and produce packaging to extending the freshness of baked goods. The gas creates an environment that’s inhospitable to many spoilage organisms.

The use of non-food-grade CO2 in these applications could introduce harmful contaminants directly into food products, potentially causing health issues or affecting taste and quality.

Chilling and Freezing Applications

In its solid form (dry ice), food-grade CO2 provides rapid freezing capabilities for many food processing applications. It’s commonly used for transporting frozen foods and flash-freezing products to preserve quality.

At -78.5°C (-109.3°F), dry ice doesn’t melt but rather sublimates directly from solid to gas, which makes it ideal for keeping products frozen without leaving behind any liquid residue.

Many restaurants and food service operations also use dry ice for interesting food presentation effects or to keep items frozen during transport or service.

Risks of Using Non-Food-Grade CO2 in Food Applications

Using industrial-grade CO2 in food applications poses serious health and safety risks. Contaminants like benzene, acetaldehyde, and sulfur compounds can be toxic even in small amounts.

Using contaminated CO2 in beverages or food can potentially lead to product quality issues, as well as health and safety concerns.

In addition, using the wrong grade of CO2 can:

• Damage equipment
• Alter product taste
• Potentially lead to regulatory violations and product recalls

These risks make proper sourcing of food-grade CO2 essential for any food or beverage operation.

How to Ensure You’re Getting Food-Grade CO2

Always purchase CO2 from reputable suppliers who specialize in food and beverage gases. Established industrial gas distributors have rigorous quality control processes to ensure their food-grade gases meet all applicable standards.

Request a Certificate of Analysis (COA) for each delivery. This document should detail the purity level and confirm that impurity levels are within acceptable limits for food-grade use.

If you’re in the food or beverage industry, consider implementing a supplier verification program that includes periodic audits and reviews of your gas supplier’s quality control procedures.

Pay Attention to CO2 Grade and Purity

Food-grade CO2 must meet stringent purity standards that industrial-grade CO2 doesn’t achieve. Understanding these differences is crucial for food safety, product quality, and regulatory compliance.

For applications involving food production, beverage carbonation, or any process where CO2 might come into contact with consumable products, only verified food-grade CO2 should be used. The health of consumers and the reputation of your business depend on making this important distinction.