Total Intensity of Odor: A New Method to Evaluate Odors

摘要

Unpleasant odors in drinking water can have a negative effect on consumer confidence. In fact, consumers often perceive that if their water smells bad, then it must be bad and unsafe to drink. Compliance for odor aesthetics of drinking water in the United States is based on a secondary standard using the threshold odor number (TON) method, a dilution-to-threshold test. However, this test has been subject to criticism in the drinking water community for being a poor measure of consumer acceptance. As a result, many utilities have turned to flavor profile analysis (FPA) to better predict consumer acceptance. However, FPA requires a trained panel, and TON remains the recommended procedure for regulatory compliance. The Metropolitan Water District of Southern California, in collaboration with Tufts University, developed a new, robust odor testing method called total intensity of odor, which offers a valid alternative for compliance purposes.