Sweet Potato
Overview
Sweet potato (scientific name: Ipomoea batatas) is a perennial tuberous root crop belonging to the morning glory genus in the family Convolvulaceae (메꽃과). It is native to the Andes region of Central and South America and to Central America, and its starch-rich roots are mainly eaten. Along with the potato, it is counted among the representative famine-relief crops and one of the world's seven major food crops, and in recent years its range of uses has been expanding as a raw material for functional foods, processed foods, and bio-materials.
Main Content
Botanical Characteristics
The sweet potato is a very close relative of the morning glory, and its flowers resemble those of the morning glory. Its stem is a creeping vine that trails along the ground, and its leaves are heart-shaped and alternate. Some of the roots extending underground become enlarged to form tuberous roots (storage roots), and this is the part we eat. Unlike the potato, the sweet potato is not a 'tuber' formed from a modified stem but a 'tuberous root' formed from a modified root, so there is no toxicity problem even when the sprouted portion (sweet potato shoots) is cut and eaten as a seasoned vegetable. However, raw sweet potatoes contain protein-digesting enzyme inhibitors and astringent-tasting compounds, so it is common to eat them cooked rather than raw.
Origin and Spread
The origin of the sweet potato is known to be the Andes region, including Peru and Ecuador, as well as Central America, where indigenous peoples cultivated it for thousands of years before the Common Era. After Columbus's voyages to the New World, it was transmitted to Europe, and then spread to Asia and Africa via Spain and Portugal. It is believed to have been introduced to East Asia through China and Japan between the late 16th and early 17th centuries. In Korea, it is said that in 1763, during the reign of King Yeongjo of the Joseon Dynasty, the envoy Jo Eom brought seeds and cultivation methods from Tsushima, Japan; records also remain that during the reign of King Sunjo, Kim Chang-je promoted sweet potato cultivation on Ulleung Island. As a famine-relief crop that prevented starvation during years of poor harvest, it holds an important place in Korean agricultural history.
Varieties
Varieties are largely divided by flesh texture and color.
- Pumpkin sweet potato: The inside is orange, rich in beta-carotene, and sweet due to its high moisture content.
- Chestnut sweet potato: High in starch, crumbly, and tasting of chestnuts.
- Watery sweet potato: Extremely high in moisture, so it becomes very watery when cooked.
- Purple sweet potato: Contains large amounts of anthocyanin pigments, making it rich in antioxidant compounds.
- Beniharuka, Hayato, Sin-yulmi, Yeonhwangmi, and others are representative cultivated varieties that were introduced from Japan or bred domestically.
Nutrition and Benefits
Sweet potatoes are high in carbohydrates but also contain dietary fiber, vitamin A (beta-carotene), vitamin C, potassium, calcium, magnesium, and more. The vitamin C in sweet potatoes is wrapped in starch and thus relatively resistant to heat, so it is not easily destroyed even when steamed or roasted. Steamed sweet potatoes have a relatively low glycemic index (GI), but roasted sweet potatoes lose moisture and gain sweetness, raising their GI, so people who need to manage blood sugar should consider their cooking method. Dietary fiber aids intestinal movement and contributes to preventing constipation, and the anthocyanins in purple sweet potatoes and the beta-carotene in pumpkin sweet potatoes are noted for their antioxidant effects.
Cooking and Uses
Sweet potatoes go well with almost all cooking methods, including steaming, boiling, roasting, frying, and braising. Representative examples include roasted sweet potatoes, sweet potato candied sticks (matang), sweet potato fries, seasoned sweet potato shoots, and sweet potato leaf wraps. Processed foods include sweet potato starch, glucose syrup, glass noodles (dangmyeon), sweet potato sticks, dried sweet potato snacks, sweet potato bread, sweet potato latte, and sweet potato beer, and recently they are also used as materials for protein- and fiber-fortified products. Beyond food, the starch is also studied as an industrial material for bioplastics, fermentation feedstock, and the like.
Cultivation and Production
Sweet potatoes grow well even in poor soil and are resistant to pests and diseases, making them highly valuable in terms of food security. Cultivation uses the method of planting seedlings (shoots), and technology to increase yields by producing virus-free 'disease-free plantlets' through tissue culture has become widespread. The world's largest producer is China, which accounts for more than half of global production, followed by African countries such as Malawi, Nigeria, Tanzania, and Uganda. In Korea, the main producing areas are Haenam in Jeollanam-do, Yeoju in Gyeonggi-do, and Dangjin in Chungcheongnam-do, and Haenam is famous as the largest sweet potato producing area in the country.
Latest Trends
In 2024–2025, the sweet potato industry is being shaped by two axes: climate change and changing consumption trends. As summer heat waves, torrential rains, and droughts repeat, crop variability has increased, and disease management—including low-temperature damage during storage and soft rot—has emerged as a major task. Accordingly, research on heat-tolerant and disease-resistant varieties and varieties dedicated to processing is active. On the consumption side, as sweet potatoes are re-examined as a 'K-dessert' ingredient, the processed market—such as sweet potato latte, sweet potato tart, sweet potato beer, and sweet potato snacks—is growing rapidly, and demand for functional foods using purple sweet potatoes and beta-carotene-fortified varieties is also increasing. Internationally, programs to distribute orange-fleshed sweet potato (OFSP) to reduce vitamin A deficiency in Africa are expanding, and the standing of the sweet potato as a crop for food security and climate response is on the rise again. Domestically, the production of plantlets using smart farms and vertical farms, standardized shipment, and the expanded distribution of disease-free plantlets continue.
Related Topics
- [[Potato]]
- [[Convolvulaceae]]
- [[Famine-relief crop]]
- [[Food security]]
- [[Beta-carotene]]
- [[Haenam County]]