Artificial Nose Technology Sniffs Out Spoilage

It’s called “smell-seeing,” an artificial nose technology developed by University of Illinois chemists Kenneth Suslick and Neal Rakow that provides a fast, inexpensive and visual means to detect odors produced by everything from sour milk to food additives.

In concept, the technology works much like litmus paper: An array of vapor-sensitive dyes known as metalloporphyrins—doghnut-shaped molecules that bind metal atoms—is placed on an inert backing such as paper, plastic, or glass. When the array is exposed to an odor-producing substance it changes color. By comparing the pattern produced to a library of color fingerprints, the user can quickly identify and quantify the chemical compounds present.

How sensitive is the technology? “The human nose is generally sensitive to most compounds at a level of a few parts per million,” explains Suslick. “The sensitivity of our artificial nose is 10 to 100 times better than that for many compounds.” Moreover, the researcher adds, smell-seeing is not at all affected by humidity.

Among the potential food and beverage applications for the technology: Detecting the presence of flavorings and food additives, and the early detection of meat & produce spoilage.