Oregano is the spice of life
Henry Tillman
Oregano originated in Europe and was first cultivated by the ancient Greeks. The name, “oregano” comes from the Greek “oros,” meaning “mountain,” and “ganos,” meaning “joy.” The ancient Greeks considered it a gift from Aphrodite. In addition to its culinary uses, oregano was commonly used to treat various maladies from toothaches to rheumatism. In China, it was used to ease gastrointestinal upset and fever.
In modern times, oregano is most commonly used in Italian and Greek cuisines, adding a sweet sharpness to tomato sauces and meats. The herb is also being studied for its antiinflammatory, antibacterial, and antioxidant properties.
Overall Health Benefits of Oregano
Oregano is an excellent source of antioxidants including carvacrol, thymol, and rosmarinic acid. It has been shown in vitro to be effective against various bacteria including Escherichia coli and Pseudomonas aeruginosa. Carvarcrol and thymol have been found to protect against some viruses in vitro, including norovirus and herpes simplex, and carvacrol has been shown in animal studies to be effective in reducing inflammation.
Oregano and Cancer
The anticancer potential of oregano essential oil has shown promise in multiple in vitro and a few animal studies.
Breast Cancer
Oregano has been shown to suppress tumor growth in a rat model of breast cancer and another study found it has the potential to modulate breast cancer growth and metastasis in vitro and in a chick embryo tumor growth assay.
Colon Cancer
A 2015 study of the effects of carvacrol on 2 human colon cancer cell lines found that the it inhibited proliferation and migration of the cancer cells in a concentration-dependent manner.
Lung Cancer
Carvacrol was shown to inhibit human non-small cell lung cancer cell growth in vitro.
Liver Cancer
In 2012, a Chinese study found that carvacrol induced apoptosis in HepG2 cells, and in another study of its effect on N-nitrosodiethylamine-induced liver injury in rats carvacrol was shown to protect against oxidative stress and therefore protect against the kind of liver damage that can result in cirrhosis, hepatitis, and cancer.
Prostate Cancer
Carvacrol has been found to suppress prostate cancer cell proliferation, migration, and invasion in vitro.
While the bulk of the current research is preliminary (animal- and cell-based), the results suggest that oregano in general and its component, carvacrol in particular, are worthy subjects of further study.
Selection, Use, and Storage
Dried oregano is readily available in supermarkets and grocery stores. Generally, you will find 2 options, Greek (Origanum vulgare), which is a member of the mint family and the subject of this article, and Mexican (Lippia graveolens), which, while also delicious, is not “true” oregano, but rather a member of the verbena family. Fresh oregano is also easy to come by in supermarkets or at the farmers market, and it is exceptionally hardy and easy to grow. Dried oregano should be stored in glass, ceramic, or plastic containers and kept in a cool, dark place. Kept this way, it will retain its flavor for up to 6 months. Fresh oregano, once harvested, will keep in the refrigerator in a plastic bag for up to a week.
Precautions
Unless you are allergic to plants in the Lamiaceae family, oregano is safe to use as a seasoning though in larger (“medicinal”) amounts it can cause stomach upset and may not be safe to use during pregnancy and breastfeeding or for people with bleeding disorders or diabetes.
The Recipes
During the month of September, we have put our spotlight on oregano, exploring its place in the substantial recipe catalog of CCSA’s resident chef, Dr. Linda Doody. We have devoured delicious Greek Lemon Herbed Potatoes, EZ-style Pork Ribs, and Chimichurri Sauce. We’ll close out this month with a stunning Swordfish Kebab recipe from The Olive and the Caper, by Susanna Hoffman (2004).
One cannot think well, love well, sleep well, if one has not dined well
Virginia Woolf
Spotlight on Oregano: Swordfish Kebab with Bay Leaf and Olive Tapenade
Ingredients
- Swordfish Skewers
- 2½ pounds swordfish, cut into 1½-inch chunks (shark can be substituted)
- 8–10 bay leaves, cut into 1-inch pieces (fresh is best)
- 1 large onion, quartered, layers separated
- 1 cup Lemon and Oil Marinade (see below)
- 2 cups Olive and Caper Tapenade (see below)
- Lemon and Oil Marinade
- ½ cup fresh lemon juice
- ½ cup olive oil
- 1 teaspoon salt
- 1 teaspoon chopped fresh oregano
- Olive and Caper Tapenade
- ¼ cup pitted Kalamata or other Greek black olives
- 4 large garlic cloves
- 4 anchovy fillets, preferably salt-packed
- ¾ cup capers, drained (The author recommends salt-packed, which are available in jars or pouches. Depending on taste and the amount of salt covering the capers, they may be rinsed before use. Bottled capers in vinegar brine are more commonly available but are more astringent than the salt-packed ones. Their flavor can be enhanced by soaking in several changes of fresh water to reduce the vinegar flavor)
- ½ cup packed fresh basil leaves
- ⅔ cup olive oil
- 2 Tbsp fresh lemon juice
- Tzatziki
- ¾ teaspoon salt
- 2–4 garlic cloves
- 1½ cups plain yogurt
- 1 small cucumber
- 1 Tbsp chopped fresh dill
- ¼ teaspoon freshly ground black pepper
- 1 Tbsp red wine vinegar
Instructions
- Swordfish Skewers
- Place the Lemon and Oil Marinade and bay leaves in a dish that is large enough to hold all the fish chunks in one layer. Add the fish and onion and turn to coat in the marinade. Marinate for 20–30 minutes at room temperature or cover and refrigerate for up to 2 hours. Turn the fish once or twice while marinating. If using, soak wooden skewers in water at the same time.
- When ready to cook, heat a grill to medium hot. String an onion, a piece of bay leaf, and then a fish chunk on a skewer (wood or metal). Repeat, in that order, until the skewer is filled, ending with a piece of onion. Fill all skewers in this fashion. Place the skewers on the grill and cook, turning once, just until white curd forms on top of the fish and the centers are a bit pink, 7–8 minutes. Let the skewers sit to allow the juices to settle, about 5 minutes. Serve accompanied by Olive and Caper Tapenade, and pass tzatziki.
- Lemon and Oil Marinade
- Stir all ingredients together in a small bowl. Use the marinade right away or set aside for several hours. Use the same day, as the lemon loses its punch over time. The recipe makes enough to marinate 2–3 pounds of fish.
- Olive and Caper Tapenade
- Place all ingredients in the bowl of a food processor and process until chopped as fine as possible. (Or use a chef’s knife to finely chop the olives, garlic, anchovies, capers, and basil. Transfer to a small bowl, add the oil and lemon juice, and mix well.) Use right away or store in the refrigerator for up to 3 weeks.
- Tzatziki
- Spread the salt on a chopping board and finely chop the garlic on top of the salt. Transfer the garlic and salt to a medium-size bowl, add the yogurt, and stir until creamy. Peel the cucumber and remove seeds, if large. Finely chop the cucumber and squeeze it to remove some of the liquid. Add the yogurt mixture to the cucumber, then stir in the dill, pepper, and vinegar. Cover and refrigerate for up to 2 days.
Notes
Notes from Dr. Doody:
In the past, I did not like swordfish at all since it always seemed dry and overcooked. To avoid this, check the internal temperature with an instant read thermometer; the target is 125°F.
The tapenade can also be served as an hors d’oeuvre on crostini (sliced and toasted baguette).