Taro soup is one of the foods that has long been savored by the residents of Seoul and the Gyeonggi-do Province area during the Chuseok holiday, which is often called a Korean version of Thanksgiving Day. Because taro helps to promote proper digestive function, dishes featuring taro have become a regular fixture on the meal table during Chuseok, when people are more prone to stuffing themselves with the abundance of delectable food on hand at gatherings with family and friends. While taro is a common soup ingredient for the residents of the Jeolla region, in various areas of the Yeongnam region (Gyeongsang-do provinces) torantang is a requisite dish for ancestral rituals.
Although tang is generally regarded as being a more formal or respectful term of Korean cuisine than guk, when referring to a soup dish, there are those who make a different distinction. In this regard, a tang soup would tend to be a main course or stand-alone meal, whereas a guk is a dish that is prepared for a meal, which is served together with various side dishes.

Background of Toran
Toran, or taro, which is regularly grown in tropical and temperate regions, will thrive in low-lying, humid areas, reaching a height of 80-120 centimeters. It is the plant’s bulbous root that is harvested and used for cooking. Its broad, round-shaped leaves, which can be 30-50 centimeters in length and 25-30 centimeters in width, are large enough to provide makeshift protection for anyone caught in a sudden downpour while out in the fields.
Although the plant’s scientific name is Colocasia, it is more commonly referred to as taro, or cocoyam. The scientific name is a compound term consisting of “colon” and “casein,” from the Arabic language. The name reflects the fact that the plant’s root is a source of food, while its flower can be used for decorative purposes.
The taro plant is believed to have originated in the tropical regions of Southeast Asia, including eastern India, Myanmar, the Malay Peninsula, and southern China. In Korea, taro has long been grown in the southern regions of Korea, centered around the Jinju area. However, in more recent times, it is also found in such areas of Gyeonggi-do Province as Gwangju, Icheon, and Gimpo, as well as in Gwangju of Jeollanam-do Province.
There are no records which detail when the taro plant was introduced to Korea or when Koreans first started to consume it. However, based on references to toran found in Goryeo-era documents, such as Hyangyak gugeupbang (鄕藥救急方, Compilation of Folk Medicine and Emergency Remedies, 1236), it has been concluded that toran was being commonly used and eaten during the time of the Goryeo era (918-1392).

Medicinal Properties
Taro has long been prized for its medicinal properties that include an ability to lower a fever, aid digestion, soothe inflammation, and relieve pain. An alkaline food, it is helpful for balancing out a meat-oriented diet. In addition, it is also an effective diuretic, along with being a natural source of the somnolent melatonin, which can provide relief for people who suffer from insomnia.
The gooey extract of taro is a type of mucin, a combination of sugar and protein. Mucin helps to promote healthy functioning of the liver and kidneys, along with providing anti-aging benefits and encouraging cell growth by facilitating the absorption of proteins. Furthermore, since mucin slows down the processing of carbohydrates, it helps to prevent an accumulation of excess fat. It is effective for treating stomach disorders and bouts of diarrhea due to excessive drinking or eating.
Although dextrin and sugar contribute to the natural sweetness of taro, its primary component is starch. It is also a source of protein, fat, fiber, carbohydrates, phosphorus, salt, calcium, potassium, and vitamins C, B1, and B2. When combined with kelp, the medicinal efficacy of taro is further enhanced. In particular, the algin and iodine found in kelp help to prevent absorption of calcium oxalate and the other harmful elements of taro, in addition to offsetting its odor, which people can find objectionable. The taste of kelp is also said to complement the taro flavor.

Stems and Leaves
Taro is a hardy and adaptable plant. When planted in the spring, it can generally be harvested by the time the cool breezes of autumn arrive. It can be stored for a long time as long as the peel is not removed. However, after harvesting the plant, people will typically remove, dry, and use the stems and leaves as a food ingredient during the winter season. The dried stems can be made into a side dish by soaking them in water, adding various seasonings, and then searing in oil, or used as an ingredient for yukgaejang (spicy beef and vegetable soup) or chueotang (spicy soup with loach or mudfish). Fresh stems can also be served as a tasty side dish. The broad, thick leaves can be eaten after being cut into slices and seared in oil. The leaves are also used as a wrap for rice or meat.

Preparation
When handling or peeling raw taro roots, people are strongly advised to wear rubber gloves, because it is possible to develop an itchy rash if your skin comes into contact with taro extract. If you do have a reaction, wash off the affected area with salt water to relieve any discomfort.
The acidity of taro is related to its presence of calcium oxalate. It is thus recommended that you boil the peeled taro roots in water, in which rice has been washed, because the phospholipids and proteins contained in this rice-rinsed water help to reduce the calcium oxalate and other components that contribute to the taro’s acidity. Peeled taro roots can also be boiled with onions, shallots, and garlic, to help reduce its odor.
Of particular note, tang dishes are known for the diversity of their ingredients, which create a delectable medley of flavors. Torantang is typically made by boiling taro roots with perilla seeds to make a thick broth. The scent of the perilla seeds helps to eliminate the unpleasant smell of the taro. A popular version of torantang is made with a variety of seafood ingredients.

Torantang
Ingredients
300 grams taro, 3 medium- or large-size shrimp, 1 sea cucumber, 1 abalone, ¼ bamboo shoot, 5 jujubes, 5 chestnuts, 2 shiitake mushrooms, 2 green chili peppers, onions, shallot, garlic, traditional Korean soy sauce, soy sauce, broth (made of kelp, dried shrimp, anchovy), sesame oil

Instructions
1 Boil the peeled taro roots, along with the onions, shallots, and garlic, in water and then rinse with cold water. Slice the boiled roots and sear with 1 tablespoon traditional Korean soy sauce, 1 tablespoon soy sauce, ½ cup broth, and ¼ tablespoon sesame oil.
2 Parboil the shrimp, and then peel and slice. Soak the sea cucumber in water and then slice. Slice the abalone into large pieces. Sear these ingredients in oil, adding soy sauce, salt, chopped onion, and garlic.
3 Cut the bamboo shoot into 4-centimeter-long pieces and slice thinly. Slice the shiitake mushroom and cut the green chili pepper into four pieces. Sear slightly in oil and then add the onion and garlic juice.
4 Boil and then peel the chestnuts. Remove seeds from the jujubes and cut into halves.
5 Boil the broth. Add all the ingredients and boil briefly, before seasoning with refined rice wine, salt, and soy sauce.