What Makes Chili Peppers Hot?

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Chili peppers come in various shapes, sizes, and colors and are often used as a spice or condiment to add flavor to dishes. Although commonly used in Southwestern and Mexican cuisine, chili peppers are also a staple in many other ethnic cuisines worldwide. The mild green bell pepper, for example, is a key ingredient in New Orleans dishes. Chili peppers have been around for 6,000 years and are indigenous to South America. Birds helped spread chili pepper seeds around the world because they lack pain receptors in their mouths and can tolerate even the hottest peppers.

The heat in chili peppers comes from capsaicinoids, a group of compounds that includes capsaicin, the primary heat-producing alkaloid present in peppers. The more capsaicin a pepper has, the hotter it tastes. Contrary to popular belief, the seeds do not cause the heat in chili peppers; instead, it’s the membrane that stores the heat. The mouth’s pain receptors, not the taste buds, transmit the heat sensation with the help of a neurotransmitter called substance P. Although capsaicin triggers a wave of fire in the mouth, it also releases endorphins in the body that can cause some people to feel exhilarated. Capsaicin also triggers thermogenesis, a fat-burning process.

Despite common misconceptions, chili peppers do not cause ulcers; in fact, capsaicin can protect the stomach lining. However, individuals taking anticoagulants, such as coumadin, should avoid consuming large quantities of hot peppers as they may thin the blood.

Have you ever eaten a spicy chili pepper and immediately reached for a glass of ice water to cool down the heat? Well, that’s not the best idea. The compounds that make peppers spicy are fat soluble, so drinking water actually makes the heat worse. Instead, try eating dairy products, bread, or chocolate to counteract the spiciness. In Mexican and Indian cuisine, sour cream and yogurt are commonly served as a side dish to tame the heat.

Now, let’s talk about the language of peppers. In the US, they are referred to as chili peppers, chilis, or chillis, while in Spain they are called chiles. The pungency of peppers is measured in Scoville Heat Units (SHU), ranging from zero for a bell pepper to over 16 million for pure capsaicin. The Red Savina habañero was once considered the hottest pepper at 577,000 SHU, but the Bhut Jolokia from India now holds the Guinness World Record at over 1 million SHU. There are three methods for measuring heat, including a taste test, the Scoville Organoleptic Test, and high-performance liquid chromatography.

So, next time you want to cool down the heat from a spicy pepper, skip the water and reach for some dairy instead. And if you’re feeling brave, try the world’s hottest pepper – if you dare!

Different Varieties of Chili Peppers

All chili peppers are consumable, but the level of spiciness and your personal taste preference is important when it comes to choosing the right chili. Chili peppers are classified by their heat level and shape, with color also playing a role in the classification [source: Texas A&M University]. Chili peppers come in a variety of shapes, ranging from short and stout to long and tapered. They also come in a variety of colors, including shades of red, green, yellow, orange, purple, brown, and black.

Thin and small chili peppers generally contain the most heat, but there are exceptions such as the banana pepper. Red varieties are typically spicier than green, but some mild cherry and pimento varieties are an exception. Ripe peppers have more heat than unripe peppers of the same type.

What makes mild chili peppers different from their spicier counterparts is their versatility. Mild peppers can be consumed raw, pickled, or roasted, or they can be utilized as an aromatic in savory dishes. Some common mild peppers include:

  • Bell – These squat, lobed peppers are the mildest and most versatile. They come in many colors and contain little to no capsaicin.
  • Banana – Some varieties, such as the slender, yellow banana-shaped chili, are extremely mild.
  • Pepperoncini – This small, slim, yellow-green chili is a Mediterranean staple.
  • Pimento – This scarlet tomato-like chili is often found inside green olives.
  • Poblano – This chili resembles a small bell pepper at the top and tapers to a point.

Spicy chili peppers are primarily used as a condiment and some common types include:

  • Anaheim – This chili is long and thin, red or green, and is a staple in Mexican cuisine.
  • Chipotle – A smoked habanero is referred to as a chipotle.
  • Habanero – This small, fiery lantern-shaped chili ranges in color from yellow to red.
  • Jalapeno – This popular two-inch red or green chili has cracks around the top and is one of the most versatile hot chilies.
  • Serrano – This small and slender chili resembles a torpedo and is frequently used in salsas.

A dried chili pepper is spicier than its fresh counterpart because the lack of moisture concentrates the flavors. If you substitute dry chili peppers for fresh ones, be sure to adjust the amount used according to your taste.

The most commonly used powdered chili peppers are cayenne and paprika. Cayenne adds heat to dishes while paprika adds seasoning. When used as a garnish, paprika adds color to a dish without affecting its taste.

In the next section, we will discuss the best ways to select, store, and prepare chili peppers.

Avoiding Extinction

Researchers believe that the heat in chili peppers ensures self-preservation. It discourages mammals from eating them, allowing their seeds to fall to the ground and propagate [source: Davis].

Choosing, Storing, and Preparing Chili Peppers

A chili pepper’s heat comes from its membrane. When selecting chili peppers, choose brightly colored ones with firm skin. Avoid any with soft, wrinkled, or bruised areas.

Chili peppers can be safely consumed before they are fully ripe. The longer they ripen, the spicier they become. If you buy red peppers that still show some green coloring, it indicates that they are not fully ripe, but peppers will continue to ripen even after being picked. Chili peppers have a long shelf life, and you can store washed, ripe peppers in the refrigerator for several weeks.

When handling hot chili peppers, it’s important to take precautions to avoid skin irritation. This includes wearing eye protection, gloves, and removing contact lenses. After handling the peppers, be sure to wash your hands and avoid touching your face. To reduce the heat of peppers, remove the seeds and membranes before slicing and dicing. Roasting peppers is a delicious way to enjoy them, but be sure to char them evenly and steam them to remove the skin. Freezing peppers is the simplest preservation method, but they can also be canned or dried. For those interested in growing their own chili peppers, they are easy to grow in well-drained soil and prefer warm environments. Soaking seeds before planting and using a starter solution can aid in germination. Chili peppers belong to the Capsicum genus and are grown worldwide, with India and New Mexico being major producers.

Indoor planting followed by transplantation after frost passes is the best way to increase the yield of chili peppers. It is recommended to plant chili pepper in trays about 10 weeks before the last frost date. Before transplanting, the plants should be hardened off to acclimate them to the new environment. To harden the plants, they should be moved outdoors for a week or two, starting with a few hours in the morning and gradually increasing the duration. Fertilize the plants after the first few flowers appear if they look yellow or lanky. Weeds should be pulled by hand, taking care not to disturb the roots, and the plants should receive two inches of water per week throughout the growing season. When the peppers are firm, they should be harvested by cutting the stem and leaving a little of it in place to increase the pepper’s shelf life. Now that you’re growing your own peppers, you can use them to spice up a variety of different dishes. However, chili peppers have many non-culinary uses as well. They are rich in antioxidants, and capsaicin, a compound present in chili peppers, exhibits antiviral and antibacterial properties. Capsaicin has several medical uses, including treating joint and nerve pain, lowering blood pressure and serum cholesterol, and treating herpes and shingles. Ongoing studies show promise in the prevention and control of conditions such as cancer, heart attacks, and strokes. Commercial uses of chili pepper derivatives include pepper spray, food and cosmetic dyes, and serving them to sleepy motorists to keep them awake at the wheel. Cayenne powder is used as a deterrent for mammals and insects, and people even add it to their socks to keep their feet warm.

Pepper spray is a type of self-defense weapon that can cause immediate blindness and severe pain when it comes into contact with the face. The active ingredient responsible for this pain is capsaicin. If inhaled, pepper spray can also lead to nausea and difficulty breathing. Interestingly, studies have shown that pepper spray is also effective against animals. For instance, a recent research revealed that a specific bear pepper spray was able to successfully fend off 94% of grizzly bear attacks.

of Maryland Medical Center. “Capsicum.” January 2, 2008. (October 26, 2009) http://www.umm.edu/altmed/articles/capsicum-000230.htm

More Information Available

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Additional Useful Links

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  • The Centers for Disease Control


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    1. What makes chili peppers spicy?

    Chili peppers contain a compound called capsaicin, which is responsible for their signature heat. When capsaicin comes into contact with our taste buds, it binds to a receptor called TRPV1, which sends a signal to the brain that we perceive as heat and pain. The more capsaicin present in the pepper, the hotter it will be.

    2. Is capsaicin harmful to our bodies?

    Capsaicin is not harmful to our bodies when consumed in moderation. In fact, it has been shown to have some health benefits, such as reducing inflammation and pain, and even aiding in weight loss. However, consuming too much capsaicin can cause discomfort and even damage to the digestive system. It’s important to listen to your body and consume chili peppers in moderation.

    3. Can eating chili peppers be addictive?

    Some people may experience a craving for spicy foods, but it’s not necessarily addictive in the same way that drugs or alcohol are. The sensation of heat caused by capsaicin can release endorphins, which are chemicals that make us feel good. This may lead to a desire to eat more spicy foods, but it’s not considered a true addiction.

    4. Why do some people seem to tolerate spicy foods better than others?

    The ability to tolerate spicy foods varies from person to person and can be influenced by a variety of factors. Genetics can play a role, as well as previous exposure to spicy foods. Individuals who consume spicy foods regularly may develop a higher tolerance over time. Additionally, certain cultures may have a higher prevalence of spicy foods in their cuisine, leading to a higher tolerance overall.

    5. Can chili peppers help with pain relief?

    Yes, chili peppers contain capsaicin, which has been shown to reduce pain and inflammation. Capsaicin works by blocking the transmission of pain signals to the brain, and it may be effective in treating conditions such as arthritis, neuropathy, and headaches. Some topical creams and patches containing capsaicin are available for pain relief.

    6. Are there any risks associated with consuming chili peppers?

    For most people, consuming chili peppers in moderation is safe and may even have health benefits. However, some individuals may experience discomfort or allergic reactions when consuming spicy foods. Additionally, consuming extremely spicy peppers can cause gastrointestinal issues, such as stomach pain and diarrhea. It’s important to listen to your body and consume chili peppers in moderation.

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