Frequently asked questions about Bitrex®
Humans are very sensitive to Bitrex®. Taste testing has determined that people can detect Bitrex® in water at 50 parts per billion. Bitrex® is aversively bitter at 1 to 10 parts per million (ppm) in water. Most consumer products become bitter at 30 to 100 ppm.
Yes. Bitter taste response has been shown in infants at birth. Testing with Bitrex® in 18-48 month olds shows an 85% volume reduction in liquids swallowed. As many poisonous plants contain bitter alkaloids, bitter taste is a natural warning to discourage swallowing developed by eons of evolution.
Bitrex® was discovered by Macfarlan Smith during research on derivatives of the anesthetic lidocaine.
The only way to test Bitrex® is human taste testing. Bitrex developed a proprietary Human Taste Test Protocol accepted by companies and governments worldwide. All testing is done at independent sensory evaluation laboratories under strict human ethics testing guidelines.
Bitter taste perception can be affected by many factors such as viscosity, solids content, inherent taste and even fragrance. Each formulation can be very different with only minor ingredient changes.
Surprisingly, many products do not taste bad and some are even sweet, like antifreeze, rat bait or lead paint. Bitrex® ensures they taste awful.
The National Safety Council and American Medical Association recommend bitter agent use, along with other safety measures, in products defined as mild to moderately toxic. Some products are not appropriate for Bitrex®, such as corrosive or highly toxic products.