Why does pepper burn? What is the hottest in the world?

Peppers burn because they have so-called capsaicinoids. These weirdly named substances have no smell or taste, but they stimulate the nerve cells in the mouth, producing that burning sensation, as if the mouth is on fire. Capsaicinoids are produced by glands located in the placentas of peppers – that whitish tissue where the seeds are attached. The “temperature” of each species of this fruit depends on the concentration of capsaicinoids it has. And, incredible as it may seem, there is even a specific unit to measure burning: the Scoville Heat Unit (SHU) – named after pharmacologist Wilbur L. Scoville, a pioneer in measuring the firepower of this condiment. The SHU of each pepper is obtained after biochemical tests in machines with high pressure liquids. The Guinness Book, the “book of records”, has already pointed out in one of its editions the Californian red savina habanero as the hottest pepper in the world, reaching the mark of up to 580 thousand SHU. Just to compare, our “very hot” and popular chilli reaches around 200,000 SHU. In a complete ranking of the most powerful species, it is likely that the chilli would get a place in the top five. But, as it is little known outside Brazil, it did not enter the most reliable list we found on the subject, which you can check below.