CHILI PEPPER — FROM BIOLOGY “HEAVY WEAPON” TO THE LEISURE OF HUMAN

In other words, people who love to eat spicy food are actually looking for pleasure by torturing themselves and hurting their poor tongue.

In 1492, when sailing west under the royal patronage of Spain’s royal court, Christopher Columbus not only carried with him the mission of finding a sea route connecting the two continents Asia — Europe. He is also responsible for saving the European cuisine that is struggling with a scarce supply of spices, especially black pepper [1].

1. Pepper Adventure: Journey to find a successor.

Before Columbus, commerce and trading between the East and West hemispheres was already quite exciting and prosperous. Formed around the 2nd century BC, the Silk Road became the vital trade route of the world on the mainland. Not only having important economic values, this is also a gateway for cultural and political exchange between the countries it passes through. At sea, the spice-laden ships began surfing back and forth between the countries of South Asia even earlier, at least from 1,500 BC [2]. Over time, along with cinnamon, ginger, turmeric and many other spice crops, black pepper has crossed oceans and is traded even in the remote corners of the Old World [3].

In the Middle Ages, spices originating from the East with their distinctive, novel aromas and flavors were rare and valuable commodities to Westerners. In case of black pepper, the supply is even more limited; since it is an indigenous plant that only grows in parts of South Asia, for example southwestern India [4]. Moreover, because transportation is very difficult and dangerous, plus the demand is quite large; this pungent spice has become the most expensive good in history.

There was a time when pepper was called “black gold” and was used as a substitute for money in buying and selling or paying taxes and fees [5]. The Romans considered black pepper as the king of spices, and it is used in 75% out of total 468 recipes recorded in Apicius — the oldest cookbook in human history [ 6].

In 408, when besieged by the army of the Visigoth under the command of King Alaric I, the Rome’s Senate council were required to pay a sizable ransom so that the city would not be attacked. In addition to gold, silver, animal hides and many other valuables, Alaric also requested an additional 3,000 pounds (~ 1,400 kg) of pepper [7]. In the end, the once flourished Roman Empire still could not escape its decline and disappearance, but its influence on culture in general and cuisine in particular; including the preference for pepper, which still exists and is widely circulated.

Back to Europe, before the historic voyage of Columbus, most major shipping routes of pepper in particular and spices in general were then under the strict control of the Muslim empire of Ottoman [8]. The few remaining had destinations at major port cities such as Venice or Genoa, which help the Italians hold distribution rights on European territory, and therefore can arbitrarily push up the price of pepper. This discontent over this monopoly was also part of the reason that Columbus and many previous explorers like Vasco de Gama or Sir Francis Drake set sail [9]. It could even be seen that the search for alternative supplies and sea routes for the spices transporting/trading were the indirect cause of the colonization and expansion of Western empires [10].

But the ship Santa Maria and its two companions, Nina and Pinta, never made Columbus reach Asia. On the Central American Caribbean island of Hispaniola, which he mistakenly thought as India, the confounded explorer came across a plant that inhabitants “deem it very wholesome and eat nothing without it”. Its pungency made him think he had found another variant of Indian pepper. When he brought the fruit back to Spain, he called it “pepper”, and went on to create a confusing name between two unrelated plants, black pepper and chili/hot pepper.

At first, chili was not very well received in Europe. But not long after that, the Portuguese brought the plant to Africa. Very quickly through trade, chili peppers began to grow in India, Japan, China, and then spread to the British colonies of America. Until 2009, data from the US Department of Agriculture showed that pepper consumption per capita per year in the US was even higher than asparagus, cauliflower or green peas [11].

If there is anything more surprising than Columbus’s “historical confusion”, perhaps it is knowing that people were willing to exchange gold for pepper, and have been struggling to find an alternative spice for it, i.e. chili. Even ignoring the economic value and lucrative merchant ships, what makes the taste buds so captivated by the burning sensation on the tip of the tongue? Why do many people enjoy indulging in pepper and chili, or even addicted to the stinging sensation of mustard and wasabi?

2. Fake it like it hot.

At first, it should be clear that pungency is not a taste like salty, sweet, bitter or sour, but a kind of sensation [12]. Exactly the feeling created by the brain being deceived.

When eating spicy foods, the receptors on the surface of the taste buds are exposed to and activated by phytochemicals in the spices. These substances cause a wide range of oral sensations, collectively known as chemesthesis, and vary depending on the compound in each spice.

More specifically, on the tongue and throat of humans and mammals, there are many receptor channels collectively known as TRP in general, in which TRPV1 are responsible for sensing and alerting the brain to dangerously high temperatures by inducing the feeling of pain [13]. When exposed, capsaicin compounds in chili peppers will activate these receptor channels, creating a burning sensation like when eating too hot food; though this never happened. With the same mechanism, piperine or sanshool in black pepper will cause the tongue to feel a little numb and gently tingle. As for allyl isothiocyanate in mustard, due to being composed of smaller and lighter molecules, it does not stick on the surface of the tongue but floats in the palate, is the author of the burning sensation straight up the nose [14].

To the brain, these unpleasant sensations are seen as harmful in the same way that it takes in physical pain or is actually heated, thereby triggering a fight-or-flight system like a defensive response when the body falls into dangerous situations. That is why we feel our heart beating fast, secreting saliva and sweat when we eat spicy food [15].

In other words, people who love to eat spicy food are actually looking for pleasure by torturing themselves and hurting their poor tongue. But it turns out, that makes eating spicy a little more sensible.

According to the hypothesis of Professor Paul Rozin, although spicy food provokes a mild defense reaction; but basically this feeling is still something harmless. They are “constrained risks” that we can afford to perceive and control, or “benign masochism” as Paul termed. When you know that you are safe from the dangers, your discomfort turns into excitement and thrilling [16]. Thus, harmless, dangerous feelings of confusion from the start can indirectly create a scenario of prosperity that comes after misfortune reached ít limit for our perception.

So far, only two mammals intentionally eat chili peppers. One is a Chinese tree shrew, which carries a mutation that makes the TRPV1 receptors less susceptible to capsaicin [17]. The other, also the one that actively seeks and enjoys the thrilling feeling by putting itself in jeopardy, with heart-stopping entertainment like rollercoasters, free-fall and movies. horror — guess who. If people compare each other to see who jumps off the plane from a higher height, then organizing a spicy food contest with chili peppers located higher on the Scoville spicy scale [18] is not too extreme. strange. Know that when you eat spicy food, your brain also releases endorphins — the hormone that helps with pain relief and powerful mood boosts [19].

In fact, the researchers also found the correlation between spicy appetite and preference for strong feelings [20]. In addition, both environmental (culture, other people…) and genetics factors have an impact on the ability of pungency tolerance [21].

Regarding genetic factors, an experiment was conducted to analyze the responses of twins to spicy foods. By comparing the likes and dislikes group, research confirmed that there is a genetic factor that plays a role in regulating the response to the feeling of spicy [22].

Environmentally, chili is not only a common culinary spice, but also used as a traditional medicine [23], making the use and consumption of chili peppers more popular in the community. Scientific evidence also shows: the more exposure to spicy foods, the more our tolerance to spicy food will increase. But that is not because the pain and burning have lessened, but because we have gradually become tougher and no longer overreacted [24].

On the plus side, spicy eating habits can reduce your risk of tumor formation, improve your sex life and help you pursue your weight loss goals more favorably [25]. Capsaicin in peppers not only has analgesic effects, but also has the ability to control symptoms related to metabolic functions such as high blood sugar, dyslipidemia or hypertension [26]. Chili also has important potential for improving vascular health [27].

Of course, too much chili pepper also leads to many harms, such as pain, inflammation and redness. Eating too spicy can cause stomach pain, diarrhea and worsen the symptoms of irritable bowel syndrome (IBS). Although there are no exact conclusions, observational studies have shown that chili consumption increases the risk of gallbladder and stomach cancer. In India, red pepper powder has been identified as a risk factor for mouth and throat cancer [28].

3. Enough pungent, eh, Mr. Chili?

Another more popular theory is that the reason people started consuming chili peppers came from the spice’s antibacterial and moldy abilities. The areas where chili are popular in culinary culture, coincidentally, are places with hot and humid tropical climates, which are favorable conditions for bacteria to multiply. And with strong antibacterial properties, the spicy spices were soon used by indigenous people to preserve and prevent food from rotting when the refrigerator was still a long way from being born [29].

This hypothesis also addresses the prior and more important question: why did chili pepper evolve to be the nowadays spicy fruit?

In fact, the very few mammals actively seek chili for food has shown the plant’s evolutionary success [30]. Although external assistance is needed to spread the seeds, the jaws and chewing patterns of herbivores can significantly impair the ability of chili pepper seeds to germinate. In response, chili has targeted TRP receptor channels, chasing harsh eaters away with an unpleasant burning stinging sensation, and keeping themselves for those who deserve more.

In addition to herbivores, peppers also use this defense system against insects — who easily pierce the pods with a pointed nozzle to absorb the fluid inside. With holes in the pods, chili peppers can continue to be easily attacked by bacteria and mold. These factors cause the plant to produce capsaicin to deal with harmful bacteria and fungi.

Of course, they were very clever to not completely make their own way. The succulent red fruit with a sharp tail was like a heat-seeker warhead, carrying chemical weapons in the eyes of herbivores or insects. But for the birds, it was an easy-to-find eye-catching gift; though it is not clear whether it tastes good or not — because they have absolutely no receptor channels that react to capsaicin. So the birds can eat chili like candy because they cannot perceive the pungent sensation. And chili has become the pioneer in the application of aerospace technology to the seedling stage in agriculture.

However, the production of capsaicin requires a huge amount of resources, and at the same time makes the plant lose more water through transpiration. That is also the reason for the emergence of some non-spicy variants of chili peppers, which will have a greater survival advantage under drought weather.

It can be said that chili peppers have been quite successful in their evolution, except for the fact that they will be eaten by a species willing to eat anything just to find a little strange feeling.

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