Sensory testing -- or sniffing -- is done under tightly controlled conditions. Tests are conducted in rooms with waterproof, seamless floors and smooth walls painted white, light gray or beige. The temperature must be between 68 degrees and 75 degrees with relative humidity at 45 percent. They can't be distracted by any other personnel, including fish industry officials – or reporters, said Steven Wilson, who oversees the inspections for NOAA.
The testers themselves must wash their hands with odorless soap and dry them with low-odor, white paper towels. They can't wear cologne or perfume -- although deodorant is OK, Wilson said -- and they must avoid eating spicy foods the day before and the day of the test, according to an industry manual.
A minimum of six 1-pound samples of seafood are collected. The testers smell each of the raw samples and record the odor, marking its intensity on a zero-to-4-point scale, with 4 being the most aromatic. They also note any unusual characteristics. An oil-tainted fish might smell "piney," for instance, with an aroma like Pine Sol cleaner, or it might smell "phenolic," with an aroma of Band-Aids.
The samples are then cooked and testers evaluate the cooked aroma and also take a tiny taste. They must spit out the samples, the manual says.
Now, let's see the process in action.