Thursday, May 17, 2012

Rhubarb in Season!


The Rhubarb

Rhubarb is a perennial plant belonging to the genus Rheum in the family Polygonaceae. It is related to buckwheat and has a slightly earthy and sour taste. Rhubarb thrives in cold climates. It originated in the regions of Western China, Tibet, Mongolia, and Siberia.

The Chinese cultivated rhubarb for medicinal purposes for thousands of years. The plant was mentioned in the Chinese materia medica compendium "The Divine Farmer's Herb-Root Classic" as early as 2700 BC. The dried root was a popular remedy for a wide range of illnesses. It has been used to cure fevers, to cure constipation and as a blood purifier. The stalks are edible, but the leaves are highly poisonous.

The word rhubarb derives from the Greek words "Rha" and "barbaron." "Rha" is a Scythian name of the Volga River in present-day Ukraine. Rhubarb grew abundantly along its banks. "Barbaron" means "foreign" or "barbarian." Together, the word "rhabarbaron" meant roughly, "A plant of the barbarians from the banks of the Volga River."

During the Middle Ages rhubarb was considered an exotic luxury in Europe. The plant had to be transported from Asia via the Silk Road and its price reflected the hazards of this trade route. Rhubarb was several times more expensive than precious herbs and spices such as cinnamon, opium and saffron. The chroniclers reported in 1542 that rhubarb sold in France for ten times the price of cinnamon. In 1657 rhubarb fetched over twice the price of opium in England.

Cultivation in Europe began in Italy around 1608 where it was used as a sweet filling for pies and tarts. By 1778 rhubarb was considered an edible plant in other parts of Europe, but it wasn't until early 1800s that the plant became widely popular. Those who ate the oxalate containing leaves got sick. This must have discouraged people from cultivation of this very interesting plant.

Health Benefits of Rhubarb

Rhubarb has many health benefits. The roots and stems are rich in anthraquinones, such as emodin and rhein. These substances are cathartic and laxative, which may explain the sporadic use of rhubarb as a weight loss aid.

The rhizomes contain stilbenoid compounds, such as rhaponticin, which seem to lower blood glucose levels in diabetic mice, however, more research has to be conducted before these compounds can be safely used in humans.

Rhubarb is very low in calories (about 25 calories per cup). It is rich in fiber (about two grams of fiber per cup) and is absolutely fat free. It also contains significant amounts of Vitamins A, C and K, and small amounts of B Vitamins. Rhubarb is rich in calcium (about 350 milligrams of calcium per cup of cooked plant) and potassium (230 mg per cup). It also provides some magnesium, manganese, iron, phosphorus, selenium, and copper.

Rhubarb is a good source of the sight and skin preserving carotenoid lutein. It contains 207 mcg lutein per cup.

Rhubarb contains such antioxidant compounds as lycopene and anthocyanins. This antioxidants fight free radicals and promote the health of your heart, eyes and immune system. They can also help prevent cancer. Cooked rhubarb delivers a good dose of lycopene, but raw rhubarb has practically none.


Rhubarb Vanilla Jam Recipe

Ingredients:
  • 8 cups diced rhubarb stalks 
  • 1 cup brown sugar
  • 2 vanilla beans
  • 4-5 Tbsp of water 
Method:
  • Place rhubarb and sugar in a heavy saucepan. Mix well.
  • Cut vanilla beans lengthwise and scrape the seeds out. Place the seeds and the split vanilla beans in the saucepan. 
  • Cook the rhubarb on a very low heat for 5-6 minutes. Stir gently from time to time. Add a little water to prevent burning. Stir again.
  • Cook for another 4-5 minutes stirring constantly until rhubarb is well cooked and has a smooth, jam-like consistency.  
  • Remove vanilla beans and discard.
  • Gently scoop the hot jam and place in clean, small jars. Let the jars open to cool off.
  • When the jam is cool enough, screw on the lids and refrigerate.
Enjoy in good company on fresh toast or croissant! 

*This jam will remain fresh in a fridge for about one week. To make it last longer you will have to pasteurize it by cooking the sealed jars in a water bath. 

By Dominique Teng

Creative Commons License
Rhubarb in Season! by Dominique Teng is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

Images by Foodista & by Howard Shooter