Curcuma

Turmeric is used as a spice as well as a colouring agent in food preparations. It is also one of the main constituents of curry, a mixture of spices particularly used in Indian cuisine. Few studies have yet evaluated the effects of turmeric consumption. In addition, most of them used turmeric (or its active ingredients) in quantities higher than what could be commonly consumed, thus falling more under the supplement than the usual spice (on this subject, see the Turmeric sheet (psn)).

Turmeric: understand everything in 2 minutes

Active ingredients and properties

Curcumin absorption : At the time of turmeric ingestion, only a small proportion of curcumin is absorbed into the body30. On the other hand, the simultaneous consumption of pepper greatly increases the bioavailability of curcumin31. For example, adding pepper to a dish containing turmeric is a simple way to increase the therapeutic potential of curcumin.

Antioxidants : Antioxidants are compounds that protect the body’s cells from damage caused by free radicals. The latter are highly reactive molecules that are believed to be involved in the development of cardiovascular diseases, certain cancers and other age-related diseases1. In one study, turmeric ranked fifth in antioxidant content among more than 1,000 foods analyzed2 (calculated from 100 g of food). Since a usual serving of turmeric is more like 2 g (5 ml), it still contributes less to our daily intake of antioxidants than other foods. Turmeric contains flavonoids and phenolic compounds3, but it is curcumin that is considered to be its main antioxidant compound.

Curcumin : Curcumin is a compound of the curcuminoid family4. It has various properties that have been mainly demonstrated in in vitro and animal studies5. Among other things, the antioxidant effect of curcumin suggests a protective effect against diseases related to oxidative stress (such as cardiovascular disease and Alzheimer’s disease)5. Curcumin also has anti-inflammatory properties and may be involved in cancer prevention at several stages of its development5. Not all of these beneficial effects have been studied in humans and the amounts of turmeric needed to observe them are not always specified.

Cancer : Turmeric is an important part of the diet of the people of India, who consume up to 2 g per day6. Although no studies directly demonstrate this, there appears to be a link between the particularly high consumption of turmeric and the low incidence of some cancers (such as colorectal cancer) in India and other Asian countries6. In smokers, a clinical trial showed that daily consumption of 1.5 g of turmeric for 30 days reduced the carcinogenic compounds present in the body7. Other preliminary studies show a potential anticancer activity of curcumin when consumed in quantities often higher than what could be consumed daily as turmeric4,8. Several animal and in vitro studies support this protective effect of curcumin, particularly against gastrointestinal and colorectal cancers9,10. Although the mechanisms of action have yet to be elucidated9, it is through its antioxidant and anti-inflammatory properties that curcumin may exert its anti-cancer effects11. Some authors hypothesize that consuming 1 teaspoon (5 ml) of turmeric per day could provide the amount of curcumin needed to have a preventive effect against cancer6.

Gastrointestinal disorders : Turmeric is traditionally used to treat various gastrointestinal disorders, such as inflammation and stomach ulcers. In this sense, it has been shown that turmeric extract inhibits gastric acid secretion in animals, which may reduce ulcer formation12. As curcumin does not appear to be responsible for these effects, further studies will need to be carried out to discover which active ingredients contribute to these effects12. In addition, the daily consumption of 3 g of turmeric for 12 weeks resulted in a complete regression of stomach ulcers in 75% of subjects13. However, this study did not use a control group (placebo) and other animal studies have shown opposite effects14. Thus, better controlled clinical studies will have to be carried out before encouraging the consumption of turmeric for the treatment of stomach ulcers.

Cardiovascular system : A few studies have shown the efficacy of turmeric extract in preventing oxidation of LDL cholesterol (“bad” cholesterol)15 and in reducing total cholesterol in animals15,16. It is increasingly clear that curcumin and its metabolites (obtained during the conversion of curcumin to other compounds in the body) are believed to be partly responsible for these effects15,17,18. These results suggest that turmeric could prevent the development of atherosclerosis and other risk factors for cardiovascular disease, but more studies in humans are needed15.

Alzheimer’s disease : Epidemiological studies have shown that the prevalence of Alzheimer’s disease is lower in some populations in India compared to other countries19,20. One of the reasons given for this observation was the higher consumption of turmeric in India, but this explanation is still not supported by scientific data. It has been shown in animals that the consumption of curcumin improves cognitive deficits related to Alzheimer’s disease, through mechanisms that are still poorly understood21,22. Probably the different properties of curcumin (such as antioxidant, anti-inflammatory and cholesterol-lowering properties) could be associated with this effect23. A study is underway in subjects with Alzheimer’s disease to evaluate the effectiveness of curcumin in slowing the disease23.

Other effects :  Turmeric is traditionally used to protect the liver against various aggressions24. Some studies have shown a hepatoprotective effect of turmeric in vitro and in animals, but no human data are currently available25. In addition, turmeric extracts have demonstrated antimicrobial properties against a variety of pathogenic bacteria, parasites and fungi, in vitro and in animals24,26.

Other properties

Is turmeric an antioxidant?

Strongly: the TAC index of turmeric is 1,593 umol.

Is turmeric acidifying?

Data not available

Does turmeric have a high glycemic load?

Data not available

Most important nutrients

See the meaning of the nutrient source classification symbols

Source Iron. Ground turmeric is a source of iron. Every cell in the body contains iron. This mineral is essential for oxygen transport and the formation of red blood cells. It also plays a role in the production of new cells, hormones and neurotransmitters (messengers in nerve impulses). It should be noted that iron in foods of plant origin (such as turmeric) is less well absorbed by the body than iron in foods of animal origin. However, the absorption of iron from plants is promoted when it is consumed with certain nutrients, such as vitamin C.

Source Manganese. Ground turmeric is a source of manganese. Manganese acts as a cofactor of several enzymes that facilitate a dozen different metabolic processes. It also helps to prevent damage caused by free radicals.

What is a “portion” of turmeric worth?

  • Weight/volume
    • Ground turmeric 2 g (5 ml)
  • Calories
    • 8
  • Proteins
    • 0,2 g
  • Carbohydrates
    • 1,5 g
  • Lipids
    • 0,2 g
  • Dietary fibres
    • 0,5 g

Source: Health Canada. Canadian Nutrient File, 2005.

Precautions

It has been well demonstrated that some compounds contained in turmeric have an antiplatelet effect in vitro27. Thus, although not evaluated in humans, the consumption of large amounts of turmeric with blood medications (such as heparin, coumadin or aspirin) may have an additional anticoagulant effect and increase the risk of bleeding28,29. People on anticoagulation therapy are strongly advised to consult a health care professional about possible interactions between their medications and certain spices.

In general, the usual consumption of turmeric does not produce any adverse effects. On the other hand, turmeric supplements are contraindicated in some cases (pregnancy, stomach ulcers). On this subject, see the Turmeric sheet (psn).

Turmeric over time

The term “turmeric” comes from Spanish, which itself borrowed it from Kurkum Arabic, which originally meant saffron. It appeared in the French language in 1559.

A spice that has merit

In English, turmeric is translated as turmeric, a word derived from the French “terre-mérite”; this is what this plant was once called, probably by allusion to yellow powder, which recalls mineral pigments.

Turmeric is a spice that has been traded for so long that its centre of origin cannot be determined with certainty. But it is thought to have originated in South or Southeast Asia, perhaps more specifically India, from where it spread throughout Asia, as well as in the Near and Middle East thousands of years ago. Its use in India dates back to Vedic times, i.e. 4,000 years or more. It was used in cooking, medicine and religious ceremonies. The Chinese and Arabs have also used it for a long time. On the other hand, in the West, apart from its medicinal and dyeing uses, its use has never been widespread. In medieval Europe, there were almost only Spaniards to appreciate it, perhaps under the influence of the Arabs who occupied their country for several centuries. Today, it is more popular, although generally limited to Indian or Arabic cuisine.

India is the world’s largest producer and consumer of turmeric. China, Bengal, Taiwan, Peru, Java, Australia, the West Indies, Indonesia, the Philippines also grow them.

Other turmeric species are grown in Southeast Asia for their young shoots, leaves, inflorescence or rhizome, which are used for cooking or herbalism.

Culinary uses

Turmeric is ideal to accompany your dishes, as for example with this recipe for broccoli and turmeric soup.

How to choose the right one

The fresh rhizome is much tastier than powder, but it is rarely found in the West. Look for Asian grocery stores. Buy the powder in small quantities only, as its aroma dissipates quickly.

Like many spices, turmeric is increasingly irradiated to increase its shelf life and limit insect or disease infestations during storage. People who oppose this process can buy turmeric from organic farming in health food stores or in the organic products section of grocery stores.

Culinary preparations

In India, it is used liberally in rice, potatoes, lentils and vegetables, and is used in almost all curry dishes and chutneys.
In Reunion Island, it is used to bind sauces and correct the acidity of certain dishes.
Nasi kuning (yellow rice): this festive Indonesian dish is made with long grain rice, coconut milk, chicken broth (which can be replaced by vegetable broth), turmeric, lemongrass, cinnamon, cloves, pandanus leaves (sold in Asian grocery stores), salam leaves (a plant of the myrtle family, which can be replaced by bay leaf) and galanga rhizome (fresh or canned in Asian grocery stores). Put all the ingredients in a saucepan or rice cooker. Remove the leaves before serving. Rice is usually presented in the form of a large cone surrounded by vegetables and meat, fish or seafood.

It can colour various preparations, such as pancake or waffle batter, or cauliflower, which is first cooked for a few minutes in boiling water and then browned with onions. Add a little water, chopped hot pepper, grated coconut, turmeric, salt, pepper and cook until tender. At the end of cooking, drizzle with lemon juice.
Or we can colour the vinaigrettes and, why not, the ice cream or sorbets.

Piccalilli: This marinade created by the English during their occupation of India includes various vegetables (small onions, cucumbers, cauliflower, green beans, green tomatoes) which are macerated for 24 hours with salt and then drained. They are then cooked with vinegar, flour, sugar (or honey) and turmeric, then put in jars.

It will also be used in cucumber marinades, with dill leaves and seeds.

Moroccan-style chicken: mix 1 tablespoon flour with 1 teaspoon cinnamon, cumin and turmeric. Coat chicken pieces with it and fry them for five minutes on each side in a little oil. Dilute 1 tbsp. flour in broth, add to chicken with dates and almonds, cover and cook for about 10 minutes or until chicken is cooked through.

Indonesian Rendang: This dish made with thin slices of beef is prepared by marinating the meat for 30 minutes in a mixture of soy sauce, onion, garlic, ginger, galanga, turmeric and water. Put all the ingredients in a blender. Use only half of the sauce to marinate the meat. The other half will be mixed with coconut milk and lemongrass, then heated over low heat until reduced by half. Then mix the two preparations and cook for about 50 minutes. Serve over rice.

It can be used to season soups, creams or velveties, such as zucchini or squash creams. To give it a little consistency, cook rice in it before mixing it in the blender, and to give it a slightly acidic note, add a dash of lemon juice at the end of the cooking.

Pilaf: add it to the pilaf of boulghour, quinoa, amaranth, wild rice, etc.

Conservation

Store the powder in an airtight container in a cool, dry and dark place. The fresh rhizome will keep for one or two weeks in the refrigerator in a perforated plastic bag.

Organic Gardening

All year round!
Turmeric can be grown in pots outdoors throughout the summer and brought in when frost threatens.

Although it is a tropical plant, you can grow a few turmeric plants at home if you start them indoors in January or February and put them in the ground once the risk of frost has been eliminated.

A piece of fresh rhizome will be planted or a plant will be obtained from a specialized nursery.

For the production of this product, use a large flower pot (at least 30 cm in diameter), filled with a very rich soil, turmeric being very demanding. Make sure to keep the soil moist but not soaked.

Harvesting takes place nine to ten months after planting. For storage, the rhizome is boiled, then peeled and dried in a dehydrator or oven set at a very low temperature until it has lost about 75% of its volume.

Ecology and environment

Indian researchers have discovered that turmeric powder can inhibit various seed-borne rice diseases. This plant, renowned for its antioxidant properties, could therefore reduce or even eliminate chemical fungicides and bactericides in rice plantations.