Sensory Testing of CO2: Comparing Traditional Sources and Biogas Carbon Capture

Comparing Biogas Carbon Capture with Conventional Sources for Sensory Evaluation of CO₂: Is Biogenic CO₂ Really Good Enough to Put the Fizz in our Drinks?

The global push for sustainability has led to the rise of innovative technologies, including biogas carbon capture, which provides a renewable source of CO₂. However, not all CO₂ is created equal, and sensory testing plays a vital role in assessing the quality, purity, and usability of CO₂ from these differing sources. This article delves into the methods used for sensory testing, its significance, and a case study of success at Apsley Farms.

The Importance of CO₂ in Industrial Applications

Carbon dioxide (CO₂) is used extensively in industries ranging from food and beverages to pharmaceuticals and welding. Key attributes for CO₂ quality include:

1. Purity: High levels of purity are essential for food and medical applications.
2. Sensory Quality: Taste and odour impact the final product, especially in beverages.
3. Chemical Stability: CO₂ must remain stable across various temperature and pressure conditions.

While traditional CO₂ sources, such as natural reservoirs and industrial byproducts, dominate the market, biogas carbon capture offers an eco-friendly alternative. Sensory testing ensures that this “green” CO₂ matches the standards of its traditional counterparts.

What is Sensory Testing of CO₂?

Sensory testing involves evaluating CO₂ for sensory attributes like taste, odor, and potential impurities. The process is conducted in specialized sensory labs, often with human panels or advanced analytical instruments such as gas chromatography (GC) or mass spectrometry (MS).

Key Components of CO₂ Sensory Testing:

1. Odor Assessment: Detects impurities like sulphur compounds that could impart off-odors.
2. Taste Evaluation: Ensures that dissolved CO₂ meets expectations for neutral or crisp flavor profiles in applications like carbonated beverages.
3. Purity Analysis: Identifies contaminants such as methane, hydrogen sulfide, or other volatile organic compounds (VOCs).

Biogas Carbon Capture: A Game Changer

Biogas plants capture methane from organic waste decomposition and refine it into biomethane. During this process, CO2 is a significant byproduct. Instead of releasing it into the atmosphere, advanced technologies capture and purify it for industrial use.

Benefits of biogas-derived CO₂ include:

• Reduced carbon footprint.
• Diversification of supply chains.
• Alignment with global sustainability goals.

How Biogas CO₂ Differs from Traditional Sources

Biogas CO₂ contains unique impurities like siloxanes and volatile acids, which must be removed to meet industrial standards. Sensory testing ensures these differences do not compromise product quality.

Case Study: Apsley Farms

Background

Apsley Farms, located in Hampshire, UK, operates a state-of-the-art anaerobic digestion facility. This farm processes agricultural waste and food waste into renewable energy and biofertilizers, capturing CO₂ as a byproduct.

Sensory Testing Implementation

To ensure the usability of their CO₂ in the food and beverage sector, Apsley Farms partnered with sensory testing labs to evaluate their captured CO₂. Key steps included:

1. Sampling: Regularly collecting CO₂ from biogas processing streams.
2. Testing Protocols: Performing odor and taste assessments, alongside chemical purity analysis.
3. Optimization: Modifying capture and purification processes based on testing results.

CO₂ Sensory Testing: Case Study Conclusion

After refinement, Apsley Farms achieved CO₂ with purity levels exceeding 99.9%, suitable for carbonating beverages. Their sensory testing program not only ensured product quality but also enabled market entry, diversifying their revenue streams.

So, is biogenic CO2 Really Good Enough to Put the Fizz in Our Drinks?

Yes, biogenic CO₂ can match or even exceed the quality of traditional CO₂ sources for beverage carbonation.

Through advanced purification techniques and rigorous sensory testing for taste and odour, biogenic CO₂ achieves the high purity standards required for food-grade applications. The success of Apsley Farms, which produces 99.9% pure CO₂ for use in carbonated beverages, demonstrates that biogenic CO₂ is a viable, sustainable alternative to traditional sources, ensuring the same crisp fizz consumers expect.

Key Takeaways – for CO₂ Sensory Testing:

• Sensory testing is essential for evaluating CO₂ quality, especially for food-grade applications.
• Biogas carbon capture presents a sustainable alternative but requires rigorous testing to ensure equivalence with traditional sources.
• The success of Apsley Farms highlights the potential of biogas CO₂ to meet industrial standards when paired with robust sensory testing protocols.

FAQs

1. Why is sensory testing important for CO₂?

Sensory testing ensures that CO₂ meets the quality requirements for its intended use, particularly in taste- and odor-sensitive applications like beverages.

2. Can biogas CO₂ match the quality of traditional CO₂ sources?

Yes, with advanced purification and sensory testing, biogas CO₂ can achieve comparable quality to traditional sources.

3. How does sensory testing work?

It involves a combination of human sensory panels and analytical instruments to detect impurities, evaluate taste, and ensure purity.

4. What industries benefit from CO₂ sensory testing?

Industries like food and beverage, pharmaceuticals, and specialty chemicals rely heavily on sensory testing to maintain product standards.

References

1. European Biogas Association. “The Role of Biogas in Achieving Net-Zero Targets.”
   https://www.europeanbiogas.eu/role-biogas-european-union-energy-transition/
2. “Standards for Food-Grade CO₂ – Purity Chart.”
   https://www.co2meter.com/en-uk/blogs/news/co2-purity-grade-charts
3. CARBON DIOXIDE FOOD AND BEVERAGES GRADE, SOURCE QUALIFICATION, QUALITY STANDARDS AND VERIFICATION, EIGA Doc 70/17
   https://www.eiga.eu/ct_documents/doc070-pdf/
4.  Apsley Farms. “Innovation in Anaerobic Digestion and CO₂ Capture.” https://www.apsleyfarms.com/co2-testing/