Real Food Right Now and How to Cook It: Turmeric

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Try to imagine Japanese curry without a rich, golden sauce. Or a tagine of chicken that hadn't absorbed a warm yellow tint. That ingredient responsible for dyeing everything from cauliflower to your fingertips yellow-orange is turmeric, a quintessential seasoning in many cuisines. But so often found as a powder in the spice cabinet, turmeric is less understood than, say, ground mustard or cinnamon. Where does it come from? And how does it affect food, beyond its tint?

Turmeric powder comes from a rhizome, or underground stem of a plant that resembles a root. The plant is a perennial herb in the zingiberaceae family, which also includes ginger. With striking flowers and tall, broad leaves, it may seem a surprise that turmeric plants are mostly cultivated for the gnarly bit hidden in the soil. But it has been for thousands of years, to serve many purposes.

A Brief History of Tumeric

Turmeric has been a player in traditional Chinese and Indian medicines (such as Ayurvedic) since ancient times. With a variety of health benefits, it has been used to help treat digestive problems, liver conditions and pain. It can be applied topically to treat wounds or skin conditions like eczema, or prevent the spread of infection. Turmeric can be used as a scrub to alleviate acne and scars, or combined with aloe vera to make a paste used to heal burns. Turmeric also contains curcumin, a chemical compound with powerful anti-inflammatory and antioxidant properties. It also contains omega-3 and omega-6 fatty acids, which can help lower bad cholesterol levels, so its use to season meats and other rich foods, beyond flavor, helps balance their effects, too.

While turmeric had already been employed in medicine and culinary arts in Asia and Africa for centuries, it was only brought to the Western World by Arab traders in the 13th century. But culinary or medicinal uses of turmeric didn't catch on so readily in Europe. Instead, Europeans used turmeric as a dye for textiles, and it was cheaper and easier to produce than saffron, which imparts a similar orange-yellow hue (turmeric is sometimes called "Indian saffron"). Marco Polo had noted turmeric as an excellent substitute for saffron. Unlike ginger, which was adopted by European and early American herbalists, turmeric didn't play a significant role in Western medicines until relatively recently.

In India, where it is believed that turmeric originated over 5,000 years ago, there are numerous ceremonies and rituals involving turmeric. The spice is often associated with prosperity and fertility, so weddings make good use of turmeric. In traditional Bengali weddings, for example, turmeric paste is applied to the bride's skin by female friends to give it a glow. Turmeric-colored clothing is often worn by bridesmaids.

Factual Tidbits

  • Try a little turmeric in the bathtub. In India, women often apply turmeric as an everyday ointment before taking a bath, and turmeric baths are found in several Indian rituals, such as the Tamil Manjal Neerattu, a coming of age ceremony. 
  • Black pepper can aid the absorption of curcumin in turmeric. It's no coincidence the two spices are often found together in blends.
  • It's believed that Hawaii also has a long history with turmeric, and ancient Hawaiians used the root for medicinal purposes such as treating infections and ulcers.
  • The word "turmeric" derives from its Latin name, terra merita, or "meritorious earth." But in Sanskrit, turmeric has at least 53 different names.
  • The Hindu god Khandoba is often depicted covered in turmeric, and when worshipping Khandoba, turmeric is sometimes offered or dusted over the worshippers.

Tumeric Cultivation

As a perennial, turmeric typically matures around August, when its flower is in full bloom. The rhizome is usually harvested once its leaves start browning and falling off the plant in autumn. These finger-shaped rhizomes can be extracted from the soil without disturbing the entire root to prevent the need for re-planting. In commercial production, the plants are dug up and the "mother" rhizomes are retained for replanting in the spring, while the "finger" rhizomes are harvested for use. These mother rhizomes produce higher yields than the fingers.

After harvesting, turmeric may be used fresh, much like ginger root. But more commonly, the rhizomes are processed into more shelf-stable dried or ground turmeric. This is done by boiling the rhizomes for about 45 minutes or until soft, which reduces its bitterness and spreads its color uniformly throughout. Afterward, it is dried thoroughly, before being ground finely.

India produces about 80 percent of the world's turmeric, while other major producers include Pakistan, China, Haiti, Jamaica, Peru, Taiwan and Thailand. Throughout India, there are regional and distinctions in turmeric, especially just after harvest and before grinding. Fresher rhizomes arrive starting in January, and turmeric is often traded fresh and intact rather than ground before meeting its final destination. This way, customers can observe the quality and freshness of the spice, whereas after grinding, the flavor and aroma of turmeric begins to fade.

Tumeric Seasonality

In commercial production, turmeric is planted in the spring and harvested 7-9 months after planting. After it's harvested and processed, turmeric rhizomes are relatively stable, and can be stored for up to one year without refrigeration. However, they're considered best when purchased freshest, just after harvest in the winter. If not processed by curing and drying first, fresh turmeric can last a few weeks, much like fresh ginger root.

Environmental Impact of Growing Turmeric 

It may be difficult to identify the exact origin of turmeric once it lands in a US grocery store, but the spice is most certainly imported from a country with a much warmer climate. Whereas US farmers have taken up growing some exotic spices like ginger, little has been heard of for its cousin turmeric. Besides ethnic groceries or specialty spice shops, turmeric is seldom found in whole form, either as fresh or dried rhizomes. Ground turmeric that dominates at the shelves in US markets has typically traveled a long way from its origin, increasing the carbon footprint of this ingredient (but compared to water-heavy produce like melons, dried spices' impact is minimal).

Turmeric can be grown in a home garden during the summer, if only for its attractive flowers. When planted as soon as frost has passed, it can grow in containers or yards outdoors wherever sunshine is abundant. It's a hardy plant, known to withstand drought and flooding, but it cannot withstand temperatures much lower than 65 degrees Fahrenheit. Turmeric prefers moist, loamy soil so watering frequently during summer months is key. In areas where turmeric is produced commercially, this may require intensive watering and irrigation. But South Asia, with its rainy monsoon season, is ideal for growing a water-intensive plant like turmeric.

Tumeric Nutrition and Effects on the Body 

Turmeric is linked to so many health benefits, from Ayurvedic traditions to the latest nutrition crazes. In addition to the antioxidant and anti-inflammatory effects known from ancient times, turmeric contains numerous essential minerals and phytonutrients. These include fiber, calcium, potassium, iron, manganese, copper and zinc. It's also rich in Vitamin B6 and Vitamin C, especially if eaten as a fresh root. Even dried, however, turmeric is among one of the top spices in terms of antioxidant strength.

Because antioxidants boost the immune system and prevent against ailments, some even suggest taking turmeric supplements. Scientists have studied turmeric's role in preventing cancers, such as breast cancer, while other studies indicate that curcumin (found naturally in turmeric) can help treat forms of cancer. Further, the anti-inflammatory effects of turmeric can provide relief against chronic pains and conditions such as arthritis.

In traditional medicines, turmeric is associated with a warming and stimulating effect on the body. Like ginger, it's believed to be especially helpful in winter, or for those who are feeling a bit weak. Instead of an elaborate curry, a simple turmeric milk can be made for quick absorption at nighttime, to aid digestion and warm the body before sleep.

More About Tumeric

Fresh turmeric rhizomes have a finger-shaped appearance, with irregular knobs that fan from a central base that's usually around an inch in diameter. It has a thin tan skin, similar to ginger, and a vivid yellow-orange interior. When processed by boiling and drying, the skin has been stripped and the flesh has shrunk significantly. These wrinkled-looking roots are evenly yellow-orange and usually cut down to shorter pieces about 1-2 inches long. Both fresh and dried turmeric can be grated into a paste or powder.

When used to season foods, turmeric has a slightly peppery, spicy flavor that can border on bitterness. However it's used often used in combination with other spices such as cumin, cinnamon and chilies, offering balance and complexity to the overall flavor and aroma of the blend. Its most recognizable trait may be its color; turmeric stains nearly everything it comes into contact with vibrant yellow. This is aided with fats, which carry the color (as well as flavor) throughout an entire dish.

How to Store Tumeric

Keep dried turmeric (either powdered or whole) in an airtight container in a dark place. Exposure to sunlight will weaken turmeric's flavor as well as its hallmark color. It's advised to use ground spices within a few months or up to one year for best flavor; if older, turmeric will still impart a bold yellow hue, but you may need to use more of the spice to achieve the same flavor. Fresh turmeric root can be stored in an airy, dry place at room temperature for about two weeks before it begins to dry and decompose; the fresh roots can also be frozen for months and thawed before use.

How to Cook with Tumeric

Because of its slight bitterness, turmeric is often paired with a subtle sweetening agent, such as honey, in cooking. To see if you like the flavor of turmeric, just try it simply in warm milk (or soymilk, almond milk or coconut milk) with a little honey stirred in. Or try this Anti-Inflammatory Tumeric Tea. And instead of buying pre-blended spice mixes, stock up on individual canisters of spices like turmeric, cinnamon, ground mustard, cumin, etc. and making your own blend, adjusting the amounts of each to taste. If you're looking for a bit more color in baked goods like cakes, cookies or breads, just add a pinch of turmeric to the dough to give it a sunny glow. This is sometimes done in pastries, like in the recipe for Jamaican patties below. Or this this recipe for Caulflower Steaks with Ginger and Tumeric

Recipe: Vegetarian Jamaican Patties With Tumeric Dough

(from Not Eating Out In New York]

(makes 6 )

Ingredients:
for the pastry:
1 cup all-purpose flour
12 teaspoon turmeric
12 teaspoon salt
4 tablespoons cold unsalted butter, cubed
about 1 tablespoon cold water

for the filling:
1 lb calabra squash (or substitute acorn or butternut), which should yield 1 cup roasted flesh
1 medium-large red pepper, diced
1 small Scotch bonnet pepper, carefully seeded and diced
12 cup shredded zucchini
14 cup diced onion
1 large scallion (or two small), finely chopped
1 large garlic clove, minced
2 teaspoons fresh ginger, grated
2 teaspoons fresh thyme
12 teaspoon cumin
12 teaspoon turmeric
14 teaspoon cinnamon
14 teaspoon nutmeg
about 112 teaspoons salt
14 teaspoon black pepper
1 teaspoon Worcestershire sauce
1-2 tablespoons vegetable oil

Method: 

  1. Sift dry ingredients together and cut in butter in a food processor or with a pastry cutter until mixture resembles coarse crumbs no larger than a pea. Add cold water a small spoonful at a time just until moist enough to form a ball. Cover with plastic wrap and chill while making the filling.
  2. Preheat oven to 375 degrees. Remove seeds from squash, and coat exposed surface of the squash's flesh with vegetable oil. Place flesh side-down on a baking tray and roast for about 40 minutes (depending on the size/shape of your squash -- mine was a clean half). Squash should be very soft to the touch when cooked through. Flip it over so the steam evaporates as the squash cools. Once it's cool enough to handle, the flesh should slip away easily from the thick skin. Transfer to a bowl and keep uncovered as to let as much liquid evaporate while you prepare the rest of the filling.
  3. Heat a large saucepan with oil. Add the onions, red pepper, Scotch bonnet, garlic, ginger, thyme and dry spices and sauté 5-6 minutes, until onions are soft. In a large bowl, combine the shredded zucchini and squash, and add the pepper sauté to the mixture. Add the Worcestershire sauce and salt to taste.
  4. Divide the chilled pastry dough into 6 equal pieces. Roll each one out on a lightly floured surface to about 6″ ; ovals. (If the edges are crackly, even them out a little with your fingers.) Divide the filling into 6 equal parts.
  5. Preheat oven to 400 degrees. Fill one side of each oval with filling, leaving at least 12″ ; on the edges. Moisten one edge with water with your fingertip and fold the other side over. Crimp edges with a fork. Place each filled and crimped patty on an ungreased baking sheet. Bake for about 25 minutes, or until tops are just lightly browner. Let cool 5 minutes before serving.

This post was originally published in January 2015.