America’s obsession with hot and spicy foods shows no signs of abating. Layering in flavors and applying peppery seasonings keeps meat and poultry relevant to today’s adventurous consumer.
The flavor sensation of heat comes from chili peppers, all of which belong to the genus Capsicum. There are many species, but only a few commonly used in food preparation; however, there are numerous cultivars and methods of preparing chili peppers, which impacts their unique aroma, taste and degree of heat.
The odorless, tasteless, crystalline chemical compound – capsaicin – found in chili peppers is responsible for the sensation of “a mouth on fire.” When consumed, capsaicin stimulates nerve endings in the mouth, triggering production of the neurotransmitter called substance P. This in turn signals the brain that the body is in pain.
The concentration of capsaicin in chili peppers is measured in Scoville Heat Units (SHU). This was originally determined using a test that measured the degree to which a chili pepper solution must be diluted before capsaicin was no longer detectable to a professional taster. Today SHU is determined in a less subjective test called high-performance liquid chromatography, which measures capsaicin content. Pure capsaicin tops out the Scoville scale at 16,000,000 SHU.
To compare, bell peppers, which are part of the Capsicum genus yet lack capsaicin, score zero on the Scoville scale, while ancho peppers, also known as poblanos, are 1,000 to 2,000 SHU. Chipotles and jalapeños range from 2,500 to 10,000 SHU. Guajillos are dried mirasol chilies, which are only about 2,500 to 5,000 SHU. Pasillas are milder, at 1,000 to 2,500 SHU.
Chili peppers possess flavor, but depending on their degree of heat, the flavor may not get tasted by the consumer. Because consumers vary in their threshold for heat, some might taste flavors while others do not.
Common flavorful chili peppers include chipotles, which are made by smoking and drying jalapeños; thereby, having a woodsy, smoky flavor. Anchos possess a rich, dark cherry and raisin sweetness. Guajillos boast a moderately spicy, tangy flavor with a touch of citrus while pasillas have a unique, complex flavor that starts out like prune and finishes with a hint of licorice.
There are several varieties of habanero peppers, ranging from little to no heat to fiery hot (500,000-plus SHU), which makes them so popular, as they can be blended together or with other ingredients to develop unique flavor profiles. In general, habaneros possess a fruity, citrusy flavor, which is why they are often paired with fruits, with mango being the most common.
At 800,000 to 1,000,000-plus SHU, the Bhut Jolokia pepper, also known as ghost pepper, was certified as the hottest chili pepper on the planet in The Guinness Book of World Records in 2007, but no longer holds that title. As of August 2013, the Carolina Reaper, which can be as hot as 2,200,000 SHU holds the title. There are also more than 10 other peppers that have since been identified that are hotter than the ghost pepper. As you can imagine, with such hot peppers, the human palate can only experience the heat. These peppers contribute no flavor to food applications.