Basic Introduction to Gaobo Water Chestnut
The Gaobo water chestnut is listed alongside the red water chestnuts of Taihu Lake and the wind water chestnuts of Jiaxing as one of the three famous water chestnuts in Jiangsu and Zhejiang provinces. The Gaobo water chestnut has four horns, with the top and bottom ones slightly longer and sharp, curling at the sides, giving it a shape akin to a goat's horn. Hence, the Gaobo water chestnut is commonly known as “Goat Horn Green.” In March 2018, the original General Administration of Quality Supervision, Inspection and Quarantine of China approved geographical indication product protection for “Gaobo Water Chestnut.”
Compared to other water chestnuts, the Gaobo variety has a thinner shell. Freshly picked, they are light green, turning orange-yellow when cooked. Young water chestnuts make for excellent fruit, characterized by their freshness, sweetness, crispness, and tenderness. Compared to pears and apples, they have a unique flavor. They can help dispel cold and heat, quench thirst, and refresh the palate; when cooked, the mature water chestnuts, eaten hot, are fragrant, sweet, soft, and starchy, comparable to Liangxiang chestnuts. The raw water chestnut kernels, shaped like ingots, can be braised with chicken or duck, providing a refreshing and not overly greasy dish, loved by all during gatherings with friends and family on Mid-Autumn Festival. Sliced or diced, the kernels can be stir-fried with meat or vegetables, all equally delicious. Chopped finely and made into a soup, they are nourishing, sweet, and an excellent restorative.
On the night of the Mid-Autumn Festival, there is a custom of moon worship in my hometown, and water chestnuts are an indispensable offering. Under the soft moonlight, a table is set with mooncakes, water chestnuts, lotus roots, pomegranates, incense lit, and a cup of fine wine poured. The scene and atmosphere are poetic and picturesque, evoking yearning.
The city of Yangzhou belongs to the transitional zone between a subtropical monsoon humid climate and a temperate monsoon climate. The main characteristics of the climate are distinct seasons, abundant sunshine, plentiful rainfall, and prevailing winds that change markedly with the seasons. Cold, dry northerly winds prevail in winter, mostly northeast and northwest; in summer, moist, warm southeast to east winds predominate, mainly southeast; spring sees more southeast winds; autumn, more northeast winds. Winter is relatively long, lasting over four months; summer comes second, about three months; spring and autumn are shorter, each around two months, making it suitable for growing Gaobo water chestnuts.
Geographical Scope
The Gaobo water chestnut is the only water chestnut in the four major types named after its place of origin, thriving in the area around Gaobo Town, Jiangdu District, Jiangsu Province. It is listed alongside Baoying lotus roots and Gaoyou double-yolk eggs as the Three Treasures of the Canal. Currently, the planting area of Gaobo water chestnuts almost covers seven towns in the northern part of Jiangdu District, bordering Gaoyou to the north, Taizhou to the east, Hanjiang to the west, and Tongyang Canal to the south. The geographical scope includes the entire town of Gaobo in Jiangdu District, Jiangsu Province, and extends to towns such as Fanchuan, Zhenwu, Wujian, Dinghuo, Dinggou, and Xiaoji. The geographical coordinates are 119°27′-54′30″E and 32°18′32″-48′N, with an average altitude of 3.8 meters. The protected area covers 525 square kilometers, with a production area of 1,200 hectares and an annual total output of 6,500 tons.
Product Characteristics
1. Sensory Features: The Gaobo water chestnut belongs to the four-horned type, shaped like a dumpling, with the front and back horns large, flat, and slightly drooping; the left and right horns are smaller, curving inward, with the tips of the four horns relatively blunt. The abdomen is asymmetrical, with one side concave and the other convex, and the shell is relatively thin. On average, the length of the water chestnut is 5.5 cm, width 4 cm, and weight around 15 grams. Fresh water chestnuts are light green, with a white tinge, and are crisp and sweet when eaten raw; cooked mature water chestnuts turn egg yellow and have a tender, starchy, and sweet taste.
2. Quality Indicators: The Gaobo water chestnut is characterized by its size, fleshy texture, high starch content, and high protein content. Testing shows that fresh water chestnuts are light green and turn pale yellow when cooked. Cooked water chestnuts have a nutty aroma similar to walnuts and a taste resembling chestnuts. The starch content of Gaobo water chestnuts is 21.9%, 1 percentage point higher than average; water content is 73%; protein content is 3.8%; the ratio of fruit to flesh is 1.3:1, compared to 1.5:1 for average water chestnuts. Levels of inorganic arsenic, lead, cadmium, and total mercury do not exceed standards; pesticides such as phenthoate, dichlorvos, deltamethrin, cypermethrin, fenvalerate, parathion, chlorpyrifos, triadimefon, carbendazim, and nitrite were not detected.
3. Quality and Safety Requirements: The production of Gaobo water chestnuts follows the local standard of Yangzhou City, Jiangsu Province, “Technical Regulations for Pollution-Free Gaobo Water Chestnut Production” (DB3210/T 037—2003). The product complies with the standard for “Pollution-Free Food Aquatic Vegetables” (NY5238-2005).
Historical Folklore
The history of the Gaobo water chestnut is long and renowned. Legend has it that when Emperor Qianlong traveled to the south, passing through Gaobo, he tasted the Gaobo water chestnuts and praised them highly. Every year before the Mid-Autumn Festival, the finest water chestnuts would be selected and sent overnight to Beijing to be enjoyed within the palace. According to town records, after the founding of New China, the State Council specifically sent a letter requesting that some water chestnut seeds be sent to Beijing, where they were cultivated in Zhongnanhai for viewing and tasting by officials and guests.