Trace sulfur impurities in carbon dioxide used for carbonation create “off taste” and “off odor” in beverage products. Since these impurities occur naturally, the CO2 purity must be monitored. The computer-controlled Gas Standards Generating System dynamically blends calibration gas standards for trace sulfur compounds in food grade carbon dioxide. Trace Source™ permeation tubes add low ppb concentrations of typical sulfur species including COS, H2S, mercaptans directly to a controlled flow of purified, beverage grade CO2 to create trace concentration calibration standards. Residual background contamination in the CO2 matrix gas is compensated for by using the Standard Additions Technique. Calibration is based on the known difference in sulfur compound concentration due to the addition from the Trace Source™ permeation tubes. A secondary dilution feature gives ppt concentrations. Concentration is adjustable over a wide dynamic range. Mixture concentrations are traceable to NIST through physical standards.
KIN-TEK Laboratories, Inc., www.kin-tek.com