Unlocking the Flavor Code: What Gives Pepper Its “Pungency”?

Did you know that kitchen pepper powder, beyond seasoning, can even be used in sunscreen formulations?

1. Overview of Pepper’s Flavor Components

Pepper is a widely used culinary spice. Its characteristic spiciness primarily stems from volatile compounds. Significant quantities of these volatiles are present throughout the plant: in the fresh pepper berries and their processed products, as well as in the leaves, flowers, and stems.

2. Decoding the Flavor of Pepper

2.1 Pepper Fruits

Based on processing, pepper berries are classified into black pepper, white pepper, and green pepper. Pepper is rich in nutrients and various bioactive constituents, including alkaloids, essential oils, organic acids, coumarins, phenolics, flavonoids, saponins, and sterols. Among these, essential oils, alkaloids, and organic acids consist of multiple substances.

Pepper essential oil (often called volatile oil) is a clear to pale amber fluid with a mellow pepper aroma—rich, natural, and refreshing. Along with other volatile compounds, it imparts the aroma and pungency of pepper. The essential oil contains a high proportion of terpenes, especially compounds like caryophyllene, limonene, and sabinene, which mainly determine pepper’s aroma and flavor.

2.2 Pepper Leaves

Pepper leaves are a major photosynthetic organ and nutrient store. Older leaves contain elevated levels of polyphenols and flavonoids. Ethanol extracts from the leaves exhibit strong antioxidant activity and contain compounds such as hinokiflavone and rhusflavone, plus minor amounts of piperine. In the essential oil of leaves, the main components are sesquiterpenes, eugenol, and methyl eugenol; among volatiles, cyclohexane, 3-methylhexane, 1,3-dimethylcyclopentane, and 1,2-dimethylcyclopentane dominate, with cyclohexane being most abundant.

2.3 Pepper Roots

Pepper roots are rich in minerals—potassium, sodium, calcium, magnesium, iron, and manganese. Methanol extracts yield around 60 phthalamide alkaloids. From ethanol and ethyl acetate extracts of root resin, 27 chemical constituents have been identified, including piperine, 1,2-Diheptylcyclopropene, and nonadecatriene. The volatile oil from roots contains 22 compounds, with trans-caryophyllene predominating.

3. Common Pepper Products in the Kitchen

The most familiar processed forms on the market are black and white peppercorns and their ground powders. In culinary use—whether adding to chicken, pan-fried fish, braised duck, soups, stir-fries, radishes, or lotus root—pepper enhances aroma, masks “off” smells, and cuts greasiness. Especially in Western cuisine and processed meats, black pepper is indispensable. It underlies numerous “black pepper” product lines like black-pepper-flavored beef, duck with aged-peel and black pepper, black-pepper-flavored tripe, black pepper duck breast, and black pepper steak.

4. Deep-Processed Pepper Products and Applications

Advanced products derived from pepper include piperine, white pepper oil, black pepper oil, white pepper oleoresin, black pepper oleoresin, and black pepper extract.

4.1 What Causes Pepper’s Pungency?

The pungency of pepper is mainly due to piperine, an amide alkaloid. Piperine has unsaturated hydrocarbon moieties, exhibiting cis–trans isomerism. The more cis (Z-) double bonds present, the more intense the pungency—similar to how different capsaicin levels make chili peppers hotter. During storage, cis-piperine can isomerize into the trans form, reducing pungency. Therefore, grinding pepper fresh preserves its “kick” much better.

4.2 Pepper Oleoresin: A Flavor Powerhouse

Pepper oleoresin retains almost all the aromatic and pungent compounds of pepper—its flavor and aroma are equivalent to about 50 times the weight of pure pepper powder. It can be used as a direct substitute for pepper in food applications. It is convenient in food processing, allows precise flavor control, and is widely used in compound seasonings, flavorings, spice sachets, prepared meat patties, sauces, and black-pepper steaks.

Global examples: Malaysia’s pepper candies, pepper sauces, pepper cakes, pepper tofu, and pepper mayonnaise; Cambodia’s Kampot pepper tea gaining popularity internationally; the U.S.’s lemon-pepper seasoning; Singapore’s white-pepper bak kut teh spice, black-pepper crab seasoning, and bak kut teh soup base.

5. Beyond the Kitchen: Pepper as a Preservation Agent

Spices not only enhance sensory appeal but also possess antimicrobial and preservative properties. For example, aqueous white pepper extracts effectively preserve chilled pork loin, while an ethanolic extract combining white pepper and cinnamon enhances the shelf life of chilled chicken. Using pepper as a natural preservative opens another avenue to increase its economic value.

6. Pepper as a Natural Skincare Sunscreen

Pepper has widespread applications in cosmetics. In Germany, Oshadhi black pepper essential oil is used for skin purification and easing muscle fatigue; in Greece, rose-pepper tightening body oil is marketed for firming and body sculpting. Common products include peppermint-pepper essential oil, black pepper essential oil soaps, etc. Importantly, piperine absorbs strongly in the UV range of 230–400 nm and has a high molar extinction coefficient—making it a promising candidate for sunscreen cosmetics.

With the continuous advancement of deep-processing technologies, the diversified applications of pepper are being steadily unlocked - bringing new opportunities for innovation across the food, pharmaceutical, and personal care industries.