Strategies for Taste-and-Odor Testing Methods

Op Flow 01/2003; 29(10):10-14.

ABSTRACT Sensory methods with detailed standard operating procedures have existed for many years. Previous editions of Standard Methods for the Examination of Water and Wastewater, as well as the current edition (1998), include the threshold odor number test, flavor profile analysis, flavor threshold test, and flavor rating assessment. An AWWA Research Foundation study, Practical Taste-and-Odor Methods for Routine Operations: Decision Tree, to be released next year, has developed new sensory methods for the water industry that includes the attribute rating test, 2-of-5 test, rating method for distribution system odors in comparison to a control, and triangle test. Many methods were derived from programs implemented by the food and beverage industries. The sensory methods can successfully be applied to solving many water industry problems, including Routine monitoring of raw or finished water to determine quality and detect aesthetic changes Evaluating treatments designed to remove tastes or odors Tracking taste-and-odor problems in watersheds Evaluating water samples from customers' premises Early warning of the occurrence of taste and odor in raw water Documenting the intensity of individual odorants during odor events Just as no single analytical chemistry method can detect all chemical contaminants in water under any given set of conditions, no single sensory method can provide all answers to taste-and-odor questions. The water industry needs a robust toolbox of methods to evaluate sensory properties of water and from which to choose the most appropriate methods to meet utility needs. Several simple, yet reliable, taste-and-odor evaluation methods are currently available to water-treatment plant personnel for day-to-day monitoring.

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