Cloves are a pungent spice found in savory dishes, desserts, and drinks. Ground or whole cloves often flavor sauces and rice dishes. Cloves are used along with cinnamon and nutmeg in sweet dishes and in drinks such as mulled wine, cider, or chai.
Cloves are a spice made from the flower buds of an evergreen tree called the clove tree (Syzygium aromaticum). Clove flower buds are harvested in their immature state and then dried. Whole cloves are shaped like a small, reddish-brown spike, usually around 1 centimeter in length, with a bulbous top. Cloves can be used whole or ground, and they have a very strong, pungent flavor and aroma.
Cloves are grown in India and Madagascar, but Indonesia is most closely associated with the production of cloves. The clove trade was so lucrative that an island chain once known as the Spice Islands (now part of Indonesia), was ceded by the British to the Dutch in exchange for a faraway settlement then known as New Amsterdam. The Dutch swapped Manhattan for cloves!
The flavor of cloves comes from the compound eugenol. A test-tube study found that eugenol stopped oxidative damage caused by free radicals five times more effectively than vitamin E, another potent antioxidant.
Cloves have been shown to have antimicrobial properties, meaning they can help stop the growth of microorganisms like bacteria. One test-tube study showed that clove essential oil killed three common types of bacteria, including E. coli, which is a strain of bacteria that can cause food poisoning.
The antibacterial properties of cloves could help promote oral health. In one test-tube study, the compounds extracted from cloves were found to stop the growth of two types of bacteria that contribute to gum disease. Another study in 40 people tested the effects of an herbal mouthwash consisting of tea tree oil, cloves, and basil. After using the herbal mouthwash for 21 days, they showed improvements in gum health, as well as the amount of plaque and bacteria in the mouth.
Cloves contain fiber, vitamins, and minerals. One teaspoon of ground cloves contains:
- Calories: 6
- Carbs: 1 gram
- Fiber: 1 gram
- Manganese: 55% of the Daily Value (DV)
- Vitamin K: 2% of the DV
Manganese is an essential mineral for maintaining brain function and building strong bones.
The eugenol found in cloves has also been shown to have anticancer properties. One test-tube study found that clove extract helped stop the growth of tumors and promoted cell death in cancer cells. Another test-tube study observed similar results, showing that concentrated amounts of clove oil caused cell death in 80% of esophageal cancer cells. A test-tube study found that eugenol promoted cell death in cervical cancer cells. An animal study showed that the eugenol found in cloves also helped reverse signs of liver cirrhosis, or scarring of the liver.
Cloves are also high in antioxidants, which may help prevent liver disease due to their ability to help decrease oxidative stress.
Research shows that the compounds found in cloves may help keep blood sugar under control. An animal study found that clove extract helped moderate blood sugar increases in mice with diabetes. Another animal study looked at the effects of clove extract and nigericin, a compound found in cloves, both on human muscle cells and in mice with diabetes. Cloves and nigericin were found to increase the uptake of sugar from the blood into cells, increase the secretion of insulin, and improve the function of cells that produce insulin.
Some of the compounds in cloves have been shown to help preserve bone mass in animal studies. An animal study found that clove extract high in eugenol improved several markers of osteoporosis and increased bone density and strength. Manganese is a mineral that’s involved in the formation of bone and incredibly important to bone health.
Some research indicates that the compounds found in cloves could help treat stomach ulcers. Also known as peptic ulcers, stomach ulcers are painful sores that form in the lining of the stomach, duodenum, or esophagus. They’re most commonly caused by reductions in the protective lining of the stomach, which are due to factors like stress, infection, and genetics. In one animal study, essential oil from cloves was shown to increase the production of gastric mucus. Gastric mucus functions as a barrier and helps prevent erosion of the stomach lining from digestive acids. Another animal study found that clove extract has effects similar to those of several anti-ulcer medications.
How to Buy
Cloves can be found in small jars in the spice section of the supermarket. You will see both the whole cloves and ground cloves. But you might be able to find them offered for a lower cost in the Hispanic food section, where they are labeled as clavos de olor, or simply clavos. International grocery stores also often sell cloves for far less than you will them in the supermarket. Some specialty markets offer Penang cloves, which are gourmet cloves that are individually selected by hand to ensure that each one is flawlessly shaped.
How to Store
Cloves should be stored in an airtight container, preferably in a cool and dark place. Whole cloves will retain their potency longer than ground cloves, remaining fresh for about a year compared to three months for ground cloves.
How to Cook
Whole or ground cloves are used to flavor sauces, soups and rice dishes, notably a number of traditional Indian dishes, and it’s one of the components of garam masala. Whole cloves are either removed before serving or picked out of the dish. Even when cooked, whole cloves have a very hard, woody texture.
Cloves can be used whole or ground.