Given that not everyone has the same tolerance for hot chilis, it would be good if there were a simple, portable means of objectively assessing exactly how hot they are. Well, scientists have developed just such a gadget – and it plugs into a smartphone.
Called the Chilica-Pod, the chili-shaped prototype was developed by a team led by Assoc. Prof. Warakorn Limbut, from Thailand's Prince of Songkla University. It utilizes single-use paper-based electrochemical sensor strips, which incorporate graphene nanoplatelets doped with nitrogen atoms.
After a dried chili sample is added to an ethanol-containing solution and shaken up, a drop of that liquid is placed on one of the strips. The capsaicin in the sample (which is the compound that makes chilis hot) oxidizes when it mixes with the graphene and nitrogen, producing an electrical current – the greater the capsaicin concentration, the higher the current.
Therefore, by measuring the strength of the current, the Chilica-Pod is able to determine the capsaicin levels of the chili in question. That information is displayed on the screen of a linked smartphone, which is running a dedicated app.
The technology has so far been tested on six types of chili, providing capsaicin readings in line with those obtained from bulkier, more expensive, lab-based equipment.
Along with its use by people such as consumers, grocers and restauranteurs, the device might also find use in the production of pharmaceuticals containing capsaicin. Among other things, the compound is claimed to burn fat, relieve pain, and reduce diabetic insulin spikes.
A paper on the research was recently published in the journal ACS Applied Nano Materials.
Source: American Chemical Society