Devil’s Tongue (Amorphophallus konjac)

by David McDaniel

A mass of compound-seeming leaves atop squishy stalks pouring out of a large pot in the central circle of the theme garden at the National Herb Garden was labeled “Devil’s Tongue.” Replanting was simple enough, and I did not think much about the plant after that. I figured it was a non-woody shrub of sorts. I recognize that the inability to categorize the plant into defined botanical terms should have tipped me off that it has an interesting life cycle, but it was not until I was making labels that I discovered just how interesting it is.

Amorphophallus konjac is a perennial corm in the Araceae family that grows a single, highly divided leaf, and once the corm reaches maturity it sends out a single inflorescence (Mahr, n.d.). The single leaf divides into the form of a small tree that serves to gather energy for the corm to either further maturity or regenerate after production of an inflorescence. The inflorescence has thousands of flowers at the base of the spadix within the spathe. The spathe is the part of A. konjac that wraps around the central spadix almost like a collar. The spadix is home to the inflorescence at its base and protrudes from the center of the spathe. The flowers are pollinated by carrion flies that are attracted to the smell of dead animals that emanates from the inflorescence (Mahr, n.d.). This plant is native to the Yunnan Province in China, but has become popular around the world for its unique culinary uses (Flora of China, n.d.). 

The corm is an engorged stem base, shaped almost like a donut, that stores energy collected by the single leaf it sends up every year. The corm of the plant is edible, but cannot be consumed raw due to the formation of calcium oxalate crystals that cause intense discomfort in the mouth and digestive system (North Carolina Extension Toolbox, n.d.). The calcium oxalate crystals are broken down at baking temperatures; therefore, the peeled and sliced corm must be baked and then ground into a fine powder before it can be used (Fern, 2010). 

The powder, when combined with water, makes a jelly. The jelly is traditionally formulated with seaweed to give it a pleasant brine flavor. It is gray when seaweed is used in preparation but is white when prepared without. In Japan, the finished jelly product is called konnyaku, konjac (NC State Extension, n.d.). The English form of the word is pronounced like the liquor, cognac. The jelly takes on the flavor and color of any additional ingredients. Modern uses still have both traditional options, but fruit and vegetables are sometimes added for flavors used in candies and the bubbles in bubble tea. In bubble tea it is used as a replacement for tapioca when a sweet flavor, as opposed to a savory flavor, is desired. More generally, the jelly can be used as a vegan replacement for anywhere gelatin is used. It can also be used as a replacement for seafood. The seaweed preparation of konjac lends a fish flavor to dishes and is used as a vegan substitute for fish. 

Another preparation of konjac is in the form of noodles. The noodles are translucent and are known as shirataki. Shirataki noodles are low calorie, gluten free, and light on carbs (Spritzler, 2018). Keto diet circles hail them as a “miracle food” since they are like wheat noodles, but are not as carbohydrate heavy or high in calories since they are 97% water and only 3% flour (Spritzler, 2018). The noodles can be substituted in recipes that have wheat noodles, provided some limitations are considered (Spritzler, 2018). The primary limitation is the lack of flavor when prepared on their own; however, the noodles will absorb a lot of flavor in the dish when cooked with other ingredients. 

The medicinal properties of konjac come from the glucomannan in the flour, as it is a source of good carbs for gut microbiota while not being available for uptake by humans (Spritzler, 2018). Feeding gut microbiota gives konjac prebiotic properties (Spritzler, 2018). The lack of bioavailability of the glucomannan is another reason konjac is popular in keto diets (Spritzler, 2018). The glucomannan also relieves constipation and symptoms of irritable bowel syndrome (Fern, 2010; Spritzler, 2018). The mechanism that allows glucomannan to work as such a good source of dietary fiber is that it has a high rate of water absorption by weight, which allows for a higher water content in bowel movements (Devaraj, 2019). The prebiotic properties are due to the preference of healthy bacteria native to the gut for glucomannan over other available sugars (Devaraj, 2019). 

The konjac at the National Herb Garden did not flower this year, but the leaves were large enough we had to plant it in the ground since it was bursting out of the pot. There’s a good chance in the upcoming years that it will flower brilliantly and I hope to see it. After reading about all of the uses of konjac I will be on the lookout for konjac foods and candies on my grocery trips! 

Photo Credits: 1) The tree-like single compound leaf of Amorphophallus konjac (Sebastian Stabinger, via Wikimedia); 2) A group of A. konjac inflorescences, showing the collar-like spathe round the central spadix (James Steakley, via Wikimedia); 3) Close-up of the winged compound leaf (David McDaniel); 4) A packet of mango flavored konjac jelly (Open Food Facts); 5) Konjac noodles (Alpha, via Flicker)

Medicinal Disclaimer: It is the policy of The Herb Society of America, Inc. not to advise or recommend herbs for medicinal or health use. This information is intended for educational purposes only and should not be considered as a recommendation or an endorsement of any particular medical or health treatment. Please consult a health care provider before pursuing any herbal treatments.

References 

Devaraj, R. D., C. K. Reddy, & B. Xu. 2019. Health-promoting effects of konjac glucomannan and its practical applications: A critical review. International Journal of Biological Macromolecules. 126: 273-281. Accessed November 6, 2022. Available from: https://pubmed.ncbi.nlm.nih.gov/30586587/ 

Flora of China (Internet). n.d. Amorphophallus konjac K. Koch, Wochenschr. Gärtnerei Pflanzenk. 1: 262. 1858. Flora of China. Accessed November 6, 2022. Available from: http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=242302696

Fern, K. n.d. Amorphophallus konjac. Tropical Plants Database. Accessed November 6, 2022. Available from: https://tropical.theferns.info/viewtropical.php?id=Amorphophallus+konjac 

Mahr, S. n.d. Voodoo lily, Amorphophallus konjac. Wisconsin Horticulture. Accessed November 6, 2022. Available from: https://hort.extension.wisc.edu/articles/voodoo-lily-amorphophallus-konjac/

North Carolina Extension Toolbox (Internet). n.d. Amorphophallus konjac. NC State Extension. Accessed November 6, 2022. Available from: https://plants.ces.ncsu.edu/plants/amorphophallus-konjac/#poison

Spritzler, F. 2018. Shirataki noodles 101. Healthline. Accessed November 6, 2022. Available from: https://www.healthline.com/nutrition/shirataki-noodles-101 

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David McDaniel is the National Herb Garden intern for the 2022-2023 season where he’s digging into the herbal uses of plants, as well as learning the ins and outs of public gardening.

The Other Quince

by Matt Millage

After a brief email exchange with a colleague last fall around this same time, I set off to collect some fallen treasures from the forest floor from a tree I had never collected from before. The fruit was large and aromatic, but I was unfamiliar with its culinary use. Suddenly the sweet scent of ripening flesh let me know that the bounty was close, and true to smell, the six-inch long, bright yellow fruits of the Chinese quince (Pseudocydonia sinensis) were scattered beneath a tree. Much larger than its cousin, the common quince (Cydonia oblonga), which is used often in fruit production and tree grafting, the Chinese quince has a reputation for being rather astringent, and I had never thought of cooking with it. 

After informing my colleague that the harvest was complete, I inquired as to how he planned on using the crop. He explained that quince made a lavish addition to an apple pie, among other seasonal dishes. From there, I dug in further to the culinary and ethnobotanical history of the Chinese quince and was pleasantly surprised to discover the versatility and medicinal properties of this interesting plant.

A monotypic species in the Rosaceae family, this tree alone could be an ornamental addition to most temperate gardens. They grow easily in USDA hardiness zones 6a-8b and in a variety of soil types.  Standing 10’ – 20’ at maturity with exquisite exfoliating bark and wonderfully scented pink-white flowers in the spring, it adds multiple layers of interest year-round. Autumn, though, is when it gives up its true prize—the large fruits which have been used historically for medicines, as an edible for jams, jellies, pie fillings, liqueurs, candies, and eaten as a sweet meat (Facciola, 1990).

Korea, Japan, and China have used the fruits medicinally for centuries as an antitussive, and for  asthma, the common cold, sore throats, mastitis, and tuberculosis. Descriptions of these efficacies have been found dating back to the 18th century in Japan. It contains several medicinally active constituents including organic acids, plus the flavonoids rutin and quercetin (World Health Organization, 1998).  Recent research has shown that extracts of Chinese quince fruit have various biological functions, such as antibacterial, antihemolytic (Osawa et al., 1997), anti-inflammatory (Osawa et al., 1999), antitumor (Chun et al., 2012), anti-influenza (Hamauzu et al., 2005, Sawai et al., 2008, Sawai-Kuroda et al., 2013), antioxidant (Hamauzu et al., 2006, Hamauzu et al., 2010), and gastroprotective (anti-ulcerogenic) (Hamauzu et al., 2008) activities. 

Medicinal plants are often boiled to extract functional ingredients, suggesting a decoction of Chinese quince fruit may be rich in various phytochemicals. Decoctions have been used for medicinal purposes but can also be used for manufacturing processed foods, such as fruit jelly. These traditional methods offer both positive and negative effects on the medicinal properties, as some research shows that the thermal effects can have a reductive effect on the polyphenols (Hamauzu et al., 2018).  

So, in addition to being a delicious addition to the fall harvest, it also has an increasing number of positive side effects attributed to its consumption. Which, I believe, begs the question, when are you going to add some quince to your apple pie? There are lots of fantastic recipes on the Internet, but here is one that I tried last year after my colleague piqued my interest enough to see how they taste during fall pie season. I hope that you enjoy it as much as I did as it truly does add a lavishness and texture that I had never experienced before with a typical apple pie. I used the Chinese quince but am sure that the common quince could be used as an easy replacement. Even if you just keep a bowl of them on the counter for a sweet fragrance, I hope that you can find a way to enjoy the Chinese quince in your home this fall, too! 

 

Apple Quince Pie

Ingredients

• 3 cups thinly sliced peeled quinces (about 2 medium)
• 1 can (5-1/2 ounces) unsweetened apple juice
• 1 teaspoon whole cloves
• Pastry for single-crust pie (9 inches)
• 5 cups thinly sliced peeled tart apples (about 5 medium)
• 1/2 cup sugar
• 3 tablespoons all-purpose flour
• 1/2 teaspoon ground cinnamon
• 1/4 teaspoon salt
• 1/4 teaspoon ground nutmeg

Topping:

• 1/3 cup quick-cooking oats
• 2 tablespoons all-purpose flour
• 2 tablespoons brown sugar
• 1/4 teaspoon ground cinnamon
• 1 tablespoon cold butter

1. In a large saucepan, combine the quince and apple juice. Place cloves on a double thickness of cheesecloth; bring up corners of cloth and tie with string to form a bag. Add to the saucepan. Bring to a boil. Reduce heat; cover and simmer for 12-15 minutes or until quince are crisp-tender.
2. Uncover; simmer 8-12 minutes longer or until liquid is reduced to 2 tablespoons. Discard spice bag. Cool for 5 minutes.
3. Line a 9-inch pie plate with pastry. Trim to a 1/2 inch beyond edge of plate; flute edges. In a large bowl, combine the apples, sugar, flour, cinnamon, salt, and nutmeg. Gently stir in quince mixture. Spoon into the crust.
4. For topping, in a small bowl, combine the oats, flour, brown sugar, and cinnamon; cut in butter until crumbly. Sprinkle over filling.
5. Bake at 375° for 50 – 60 minutes or until the apples are tender and crust is golden brown. Cool on a wire rack.

Photo Credits: 1) Chinese quince flower; 2) Exfoliating bark; 3) Chinese quince hanging from branches; 3) A large, fully ripe fruit. All photos courtesy of the author.

Medicinal Disclaimer: It is the policy of The Herb Society of America, Inc. not to advise or recommend herbs for medicinal or health use. This information is intended for educational purposes only and should not be considered as a recommendation or an endorsement of any particular medical or health treatment. Please consult a health care provider before pursuing any herbal treatments.

References

Chun, J.M., K.J. Nho, A.Y. Lee, et al. (2012). A methanol fraction from Chaenomeles sinensis inhibits hepatocellular carcinoma growth in vitro and in vivo. Journal of the Korean Society for Applied Biological Chemistry. 55: 345-351.

Facciola, S. (1990). Cornucopia: A Source Book of Edible Plants. Vista, California: Kampong Publications.

Hamauzu, Y., T. Inno, C. Kume, M. Irie, and K. Hiramatsu. (2006). Antioxidant and antiulcerative properties of phenolics from Chinese quince, quince, and apple fruits. Journal of Agricultural and Food Chemistry. 54: 765-772.

Hamauzu, Y., M. Irie, M. Kondo, and T. Fujita (2008). Antiulcerative properties of crude polyphenols and juice of apple, and Chinese quince extracts. Food Chemistry. 108: 488-495.

Hamauzu, Y., H. Kishida, and N. Yamazaki. (2018). Gastroprotective property of Pseudocydonia sinensis fruit jelly on the ethanol-induced gastric lesions in rats. Journal of Functional Foods. 48: 275-282.

Hamauzu, Y., H. Yasui, T. Inno, C. Kume and M. Omanyuda. (2005). Phenolic profile, antioxidant property, and anti-influenza viral activity of Chinese quince (Pseudocydonia sinensis Schneid.), quince (Cydonia oblonga Mill.), and apple (Malus domestica Mill.) fruits. Journal of Agricultural and Food Chemistry. 53: 928-934.

NC State Extension. Pseudocydonia sinensis Fact Sheet. Accessed on Oct 5, 2021 from NC State Extension https://plants.ces.ncsu.edu/plants/pseudocydonia-sinensis/

Osawa, K., K. Miyazaki, H. Imai, and K. Takeya. (1999). Inhibitory effects of Chinese quince (Chaenomeles sinensis) on hyaluronidase and histamine release from rat mast cells (in Japanese with English summary). Natural Medicines. 53: 188-193.

Osawa, K., H. Yasuda, H. Morita, K. Takeya, and H. Itokawa.  (1997). Antibacterial and antihemolytic activity of triterpenes and β-sitosterol isolated from Chinese quince (Chaenomeles sinensis) (in Japanese with English summary). Natural Medicines. 51: 365-367.

Sawai, R., K. Kuroda, T. Shibata, R. Gomyou, K. Osawa, and K. Shimizu. 2008. Anti-influenza virus activity of Chaenomeles sinensis. Journal of Ethnopharmacology.118:108-112.

Sawai-Kuroda, R., S. Kikuchi, Y.K. Shimizu, Y. Sasaki, K. Kuroda, T. Tanaka, and T. Yamamoto, et al. 2013. A polyphenol-rich extract from Chaenomeles sinensis (Chinese quince) inhibits influenza A virus infection by preventing primary transcription in vitro. Journal of Ethnopharmacology. 146: 866-872.

World Health Organization, R. O. (1998). Medicinal plants in the Republic of Korea : information on 150 commonly used medicinal plants. Manila: WHO Regional Publications: Regional Office for the Western Pacific.

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Matt has worked in public gardening for a little over six years and is currently the horticulturist in the Asian Collections at the U.S. National Arboretum. He previously worked at Smithsonian Gardens in a variety of capacities. Matt is an ISA-certified arborist and an IPM manager certified with both Virginia and DC.

Camellia sinensis – Herb of the Month

By Maryann Readal

Tea is the most widely consumed beverage in the world, after water. Countless books have been written about tea, which is the leaf product of this herbal shrub, Camellia sinensis. The history of C. sinensis and its product goes back almost 5,000 years, and it is believed to be one of the oldest plants cultivated by humans. C. sinensis is truly a plant that has been responsible for wars, influenced social customs worldwide, inspired religious practices, and, of course, has lifted many troubled and tired spirits with its medicinal properties. 

Camellia sinensis is an evergreen shrub or small tree that is usually trimmed to about six feet when cultivated for its leaves. It thrives in acidic, rich soil where rainfall is adequate throughout the year, and grows in dappled shade to full sun. It is winter hardy in zones 7-9 when grown as a landscape shrub, but it can also be grown in a pot and moved indoors or grown in a greenhouse where winter temperatures fall below freezing. The fragrant white flowers have  yellow stamens and bloom in the fall to early winter and are attractive to pollinators.

Radiocarbon dating has placed some ancient C. sinensis shrubs growing in regions of China at up to 3,200 years old. Some of these old shrubs have been cut down to make way for growing rubber trees.

The new leaves of Camellia sinensis are harvested for tea. All types of tea come from two C. sinensis varieties: Camellia sinensis var. sinensis (Chinese tea) and Camellia sinensis var. assamica (India tea). Six true teas come from C. sinensis: black, white, oolong, green, pu-erh, and a rare yellow tea (all other “teas” are infusions of flowers, herbs, roots, or bark, and are properly called tisanes). The differences in taste, color, and aroma of these teas depend on where they were grown, their variety, and the processing of the leaves. The small white flowers of C. sinensis are edible and are used to brew a sweet, rich drink. China is the number one producer of tea, producing two million tons annually. India, Kenya, and Sri Lanka follow China in tea production in that order. Interestingly, Turkey is the largest consumer of tea per capita.

The tea plant contains over 500 compounds that contribute to its flavor and health benefits. Green tea’s first recorded use in ancient China was for medicinal purposes, where it was used as a preventive drink for many health problems. Even today, green tea is used to boost the immune system, and researchers have found it to be an effective ingredient in cosmetic products to block UV rays and to reduce cellulite tissue. Though all teas have medicinal benefits, black tea contains antioxidants and other compounds that are particularly good for heart and gut health. Researchers have found that older C. sinensis shrubs grown at higher elevations have the most medicinal compounds.

The history of tea is a long one. In one popular Chinese legend, Emperor Shen Nung, known as the Father of Chinese medicine, in 2737 BCE was drinking a bowl of hot water when the leaves of the tree he was sitting under dropped into his water. After taking a drink of the water, he observed a nice flavor and felt restored. He encouraged people to cultivate the tea plant. And with that, tea as an important commodity and drink was born.  

Tea was introduced into Japan and Korea by Buddhist monks in the 6th century, where it became a drink of the religious classes. The tea ceremony, developed by Buddhist monks, became an important social custom. Tea was considered a medicinal drink at that time. Portuguese priests and traders brought tea to the west in the early 16th century. Drinking tea became popular in Britain in the 17th century, and tea became a worldwide industry with huge demand. 

An interesting tea story reveals that the British introduced tea cultivation in India to compete with the Chinese monopoly of tea. As tea consumption grew around the world, the British became the major supplier of the product. Tea had to be paid for in silver bullion, and some British feared damage to their economy as a result of the loss of so much bullion. As a way to generate more bullion, Britain began exporting opium to the Chinese and increased imports fivefold between 1821 and 1837. Seeing the effects of opium on their people, the Qing government banned the import of opium into China. The banning of opium created financial exchange problems for the British and was one of the causes of the First Opium War. It was at this time that the British brought the tea plant to their colony in India and began growing it to fill worldwide demand for the leaves. 

The British Tea Act ignited the American Revolution with the Boston Tea Party when 342 tea chests were dumped into the harbor. Americans switched from drinking tea to drinking coffee and teas made with other plants. But the American’s love of the true tea continued even after the war. Fast American clipper ships began sailing to China to bring home the product. It’s interesting to note that the first three American millionaires—T.H. Perkins of Boston, Stephen Girard of Philadelphia, and Jacob Astor of New York—all made some of their fortune in the tea trade.

It is a long and interesting history for this simple drink brewed from the leaves of the C. sinensis plant. The story continues with iced tea, tea bags, matcha tea, chai, and now bubble tea and tea-infused cocktails. While old tea leaves from the ancient trees have become a valuable investment for some, tea connoisseurs believe that artisanal teas produced in the ancient art of tea processing are a promise for the future. 

As we drink our cup of tea, we should remember that every tea leaf is touched by human hands. An interesting, well-researched fiction book about the tea plant is Lisa See’s The Tea Girl of Hummingbird Lane. It is a fascinating story of the history of tea and tea making in China.

For more information about Camellia sinensis, recipes, and a screen saver, go to the Herb Society of America’s webpage https://www.herbsociety.org/hsa-learn/herb-of-the-month.html. 

(Editor’s Note: Check out our recent post by Matt Millage for info on other Camellia species: https://herbsocietyblog.wordpress.com/2020/11/16/not-just-for-teatime-the-herbal-significance-of-camellias/)

Photo Credits: 1) Camellia sinensis leaf and flower (Pancrat via Wikipedia Commons); 2) Different teas and their colors (Wikimedia Commons); 3) Japanese tea ceremony (Wikimedia Commons); 4) Picking tea in China (Wikimedia Commons)

References

Koch, W., Zagórska, J., Marzec, Z., & Kukula-Koch, W. (2019). Applications of Tea (Camellia sinensis) and its Active Constituents in Cosmetics. Molecules (Basel, Switzerland), 24(23), 4277. https://doi.org/10.3390/molecules24234277  Accessed 5/3/21.

Not Just Tea Panel: The Untold History and Future of Tea. (2020) https://www.youtube.com/watch?v=vMsZGkG1Myc. Accessed  5/17/21.

Reich, Anna. (2010). Coffee and Tea History in a Cup. The Herbarist. 76, 8-15.

See, Lisa. (2017). The Tea Girl of Hummingbird Lane. New York, Scribner.

Tea Crossing. Where Does Tea Come From? Complete Guide: Camellia Sinensis. (2021). https://teacrossing.com/where-does-tea-come-from-complete-guide-camellia-sinensis/ Accessed 5/3/21.

Wikipedia. History of Tea. (2021) https://en.wikipedia.org/wiki/History_of_tea  Accessed 5/3/21.

Medicinal Disclaimer: It is the policy of The Herb Society of America, Inc. not to advise or recommend herbs for medicinal or health use. This information is intended for educational purposes only and should not be considered as a recommendation or an endorsement of any particular medical or health treatment. Please consult a health care provider before pursuing any herbal treatments.

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Maryann is the Secretary of The Herb Society of America and a Master Gardener. She is a member of The Society’s Texas Thyme Unit in Huntsville, TX. She gardens among the pines in the Piney Woods of East Texas.