Molecule of the Month

Capsaicin

Do you enjoy hot wings, spicy nachos, or Hunan cuisine? Have you ever wondered what makes spicy food taste "hot?" The answer can be found in a group of fat-soluble, organic molecules called the capsaicinoids. The molecule capsaicin is the most common of this group. Capsaicinoids were originally isolated from hot peppers. Most of capsaicin (up to 80 percent) is found in the seeds and membranes of the pepper. If you're familiar with spicy foods, you're probably aware of some of the properties of capsaicin.

It's the culprit responsible for the intense burning sensation hot peppers produce that can severely irritate the skin and eyes. The incendiary properties of a pepper are measured in Scoville Units. The Scoville Rating, originally called the Scoville Organoleptic Test, was subjective. This test was developed by William Scoville in the early 1900s and used human subjects to assess the pungency of the hot pepper.

Today, the amount of capsaicin found in a pepper can be measured objectively by high performance liquid chromatography (HPLC).

The decongestant properties of capsaicin can also help account for the runny nose that you may have experienced during your last spicy meal.

What's the best way to reduce the fiery sensation capsaicin causes? If you remember that capsaicin is a fat-soluble organic molecule, it will be of little surprise to you that the ingested fat from dairy products, such as milk or sour cream, reduces the "heat" caused by capsaicin by binding to the molecule and removing it from the tongue. Because capsaicin is only slightly soluble in water, using water to cool the heat may simply serve to spread the capsaicin around the mouth and cause further discomfort.

Who said you never learn anything useful from chemistry?