From the bell pepper in your salad, to pepperoncini flakes on pizza, smoked paprika in paella or a pinch of chilli powder in a curry, the chilli pepper, be it spicy or not, is a staple of day to day cooking. How did chillies spread around the world? And, what’s the difference between a bell pepper and a habanero? What makes some chillies spicier than others, and why, when eating spicy do we feel euphoric, and not just in pain?
Chilli peppers: a brief history
Despite them being traditionally used in many cuisines around the world today, chilli peppers originated in Mesoamerica. They were brought to Europe and the rest of the world during the Columbian Exchange, in the 15th century. While pepper was only available to the high society, chillies were often the spice of the poor.
Today, their use and commonality varies based on the region and climate. For example, countries with a hot climate, such as India, Malaysia and Thailand tend to use chillies more than those with a moderate or cool climate. This is because bacteria strives in the heat, and chillies have great antimicrobial abilities.
The 5 members of the chilli pepper family
Throughout the years, the chilli pepper plant has been domesticated and evolved. Today there are five main species, each with unique and well defined features:
- Bell peppers, cayenne, jalapeño and paprika are all part of the capsicum anuum family. This is the most common and mildest type of chilli. The plant’s flowers are white (and sometimes purple), and the fruits range from green to yellow, orange and finally, red, depending on how ripe they are.
- Capsicum chinense are famous for their intensely spicy features. Habanero, scotch bonnet, ghost, naga and carolina reaper are all part of this family. This is hobbyists’ favourite species, since the world’s spiciest chillies are all part of it.
- Tabasco (yes indeed, like the sauce), as well as birds’ eye chilli (particularly popular in Asian cuisines) are part of capsicum frutescens. This species is closely related to capsicum anuum, which makes cross pollination impossible.
- ‘Ají’, the chilli peppers used mostly in South America, are part of the capsicum baccatum family. They tend to have a fruity aroma and the flowers are often white with a green corolla.
- Capsicum pubescens have two defining features: like the name suggests, their leaves are hairy, and the seeds of the chilli fruits are black. Rocoto and manzanilla are two of the famous chillies part of this species.
I believe it’s in our nature to measure defining features of the things that surround us. Scientists track spiciness on a scale called after its inventor, Wilbur Scoville. This measures the level of capsaicin, the oily molecule that gives chilli peppers their spiciness. A bell pepper, for example, has 0 Scoville units, but pure capsaicin defines the highest end of the spectrum, at 16 million units.
Creating the spiciest chilli in the world is a real challenge for chilli-heads. This happens through complex processes. Cross pollination, thus creating hybrid varieties, is the starting point. But the level of capsaicin in a chilli is not only defined genetically (through the DNA inside the seed), but also through external factors. The type of soil and nutrients inside it, as well as the plant’s exposure to heat and sunlight are some of the elements responsible for a chilli’s spiciness.
In 2013, Carolina Reaper was officially recognised as the world’s spiciest chilli. The chilli measured 2.2 million Scoville units, and is likely to be dethroned by Dragon’s Breath, a chilli that unoficially reached 2.4 million Scoville units.
Why does it burn?
If the tongue hadn’t been equipped with capsaicin receptors, we wouldn’t feel pain when biting into a spicy chilli. As a matter of fact, there are no receptors to capsaicin in the rest of our body (aside from the tongue and the anus). Imagine feeling the burning sensation all the way down the 9 meters of your digestive system. And yet, why does it burn?
Receptors are organs or cells that respond to a stimulus and send a message to a sensory nerve. The latter makes us feel a specific sensation. We feel a burning sensation when eating spicy because capsaicin and heat activate the same receptor.
What happens when you bite into a chilli
When biting into a spicy chilli, capsaicin, together with all the other flavour compounds get released in your mouth. Your taste receptors (those for sweet, salty, sour, bitter and umami) will create a first flavour profile of the fruit. Your retronasal olfaction (breathing through the back of your mouth), will help you feel the aroma. Chewing helps you feel the texture and hearing lets you experience the crunch.
At the same time, capsaicin binds to the heat receptors and sends a signal of burning to the brain. At that point the brain releases endorphins and dopamine. Endorphins block the transmission of pain, and dopamine handles pleasure and reward. This is why, despite the pain, we often feel a euphoric high when eating spicy.
What do you do to stop the pain?
Do you trust your friends who tell you that bread, beer or fat alleviate the burning sensation of spicy food? Because I don’t, and you should not either. When suffering from too much spice, consume whatever dairy product is at hand. Dairy products contain casein, a molecule that binds to oily molecules such as capsaicin, surrounds them, and washes them away. Whether it’s cheese, yogurt, cream, milk, or, best, ice cream (since it cools you down as well), just leave the bread and beer for after you’re done with the suffering!
Chilli plants need a lot of warmth, sun and water to grow. They are perennial, but will most likely not make it through cold winters, unless you move them inside the house. The plants can survive up to five or six years, and can grow up to over a metre tall.
If you come across a chilli that you like the flavour of, you can harvest its seeds and plant them the next spring. All you need is to make sure that they dry well before you store them over the winter. For the seeds to work, the chilli needs to be ripe. This means that if it’s still green, the seeds won’t germinate. They will look shrivelled and very thin, and, if you let them dry, they will blacken.
How to plant chilli seeds
When you wish to plant them, your best bet is to do it in reusable cups or shot glasses, 2-3 seeds at a time. But don’t forget to pinch some holes at the bottom, to let the excess water get out. Placing them in a little warm water for 10-15 minutes can help revive them. Some say that the seeds that sink have 100% germination rate, but others consider this a myth. My 70 chilli seeds germinated whether they sunk or not. Plant the seeds 1 cm below the surface, and place the pots in direct sunlight, preferably inside the house. Keep the earth moist, but don’t water them excessively! And, make sure to use organic earth that’s suitable for growing plants (rather than the type for grown plants)!
Once the chilli plants have grown their 3rd or 4th set of leaves, it’s time you separate them and repot them. You should be careful when separating the roots, as this can damage the plant. Pot each chilli plant separately, and let the grow and flourish. Water them enough to look firm and happy, and repot them again if the plant grows much larger than the pot! You can keep them outside all summer long, and move them inside before the first frost.
Did you enjoy reading this article, and wish to dive deeper into the science of food? Check out this article where you’ll find 35 fascinating science-backed food facts!