The International Society of Beverage Technologists  (ISBT)

The following paragraph is excerpted from the ISBT website.

The ISBT was founded in Washington, D.C. in 1953 and now consists of over 1,000 members worldwide vision is to be the premier international technical society for the beverage industry.  It is unique in being the only organization whose sole interest is the technical and scientific aspects of soft drinks and beverages.  Its mission is to enhance the promotion, development and dissemination of knowledge relating to the art and science of beverage technology for the non-alcoholic beverage industry… by providing forums for scholarly discussion, stimulating the application of science in the industry, and publishing “voluntary” technical standards & guidelines.

ISBT CO2 Quality Guideline dated September 2006

The quality guideline was been developed by the ISBT to provide guidance for manufacturers of carbonated beverages and suppliers of carbon dioxide to the carbonated beverage industries about key characteristics for the quality and purity of carbon dioxide when used as a direct food additive in beverages. The following table lists the voluntary quality standards taken from the ISBT guideline document with relation to CO2 quality.

Fountain Beverage Quality Carbon Dioxide Purity Guildeline

Parameter: Guideline. Rationale

  • Purity: 99.9 % v/v min. Process
  • Moisture: 20 ppm v/v max. Process
  • Oxygen: 30 ppm v/v max. Sensory
  • Carbon Monoxide: 10 ppm v/v max. Process
  • Ammonia: 2.5 ppm v/v max. Process
  • Nitric Oxide / Nitrogen Dioxide: 2.5 ppm v/v max. (each) Regulatory
  • Non-volatile Residue: 10 ppm w/w max. Sensory
  • Non-volatile Organic Residue: 5 ppm w/w max. Sensory
  • Phosphine: To pass test (0.3 ppm v/v max.) Regulatory
  • Total Volatile Hydrocarbons (as Methane): 50 ppm v/v max. including 20 ppm v/v max. as total nonmethane hydrocarbons. Sensory
  • Acetaldehyde: 0.2 ppm v/v max. Sensory
  • Aromatic Hydrocarbon Content: 20 ppb v/v max. Regulatory
  • Total Sulfur Content (Total sulfur-containing impurities excluding sulfur dioxide): 0.1 ppm v/v max. Sensory
  • Sulfur Dioxide: 1 ppm v/v max. Sensory
  • Odor of Solid CO2 (Snow): No foreign odor Sensory
  • Appearance in Water: No color or turbidity Sensory
  • Odor & Taste in Water: No foreign odor or taste Sensory
Rationale definitions:
Sensory: Any attribute that negatively impacts the taste, appearance, or odor of beverage.
Process: Any attribute that defines a key parameter in a controlled process and an important consideration in the beverage industry
Regulatory: Any attribute whose limit is set by governing regulatory agencies