Rich Flavor of Cu Da Soy Sauce

Cu Da village in Cu Khe commune, Thanh Oai district, Hanoi, is an ancient village with a 500-year history, famous for two traditional crafts: glutinous rice soy sauce and glass noodle production. The villagers take pride in their centuries-old soy sauce craft, honored in the well-known saying: “Cu Da soy sauce, Dam pickled eggplant.” Today, Cu Da soy sauce holds a 3-star OCOP (One Commune One Product) certification and is steadily growing its presence in markets nationwide.

According to local artisans, Cu Da soy sauce is known for its uniquely sweet aroma and flavor. It is slightly brown, naturally sweet, mellow and savory as it is made with meticulous traditional techniques passed down through generations, from selecting premium glutinous rice, steaming the rice, roasting soybeans and mixing fermented liquids, to taking care of fermentation and mold cultivation stages. Cu Da soy sauce is well-known in Vietnamese culture through a popular folk verse “Wherever I go, I long for home/For morning glory soup, for eggplants soaked in soy sauce/Though rivers and waters may keep us apart/ Our hearts long for Cu Da soy sauce.” Cu Da soy sauce has become a culinary specialty that enriches the cuisine of Hanoi and Vietnam at large.

Walking through Cu Da, you are enveloped by the fragrant aroma of ground soybeans and freshly made batches of soy sauce. According to village elders, the soy sauce making trade is as old as the village itself, spanning over 500 years. For generations, this traditional trade has been a precious legacy passed on by predecessors. Artisans emphasize that the distinction of Cu Da soy sauce lies in its natural sweetness and fragrance. Achieving this requires meticulous, labor-intensive processes. The Cu Da soy sauce is made from two primary ingredients: sticky rice and soybeans. The rice must be the first-class Nep Cai Hoa Vang variety (a Vietnamese traditional variety of glutinous round grain rice), and cannot be mixed with regular rice, while the soybeans are selected from climbing varieties with small, pale yellow grains.

The production process includes two major stages: cultivating mold and processing the soybeans. The rice must be harvested fresh from Hai Hau district (Nam Dinh province), carefully sifted and dried in the sun. Premium soybeans are sourced from remote rural markets where a specific variety with large, even-sized, golden grains is cultivated. They are meticulously sorted to remove any damaged or flat seeds.

Cu Da soy sauce is renowned for its distinctive sweet aroma and flavor

Roasting the well-done soybeans is a delicate step requiring skills. The beans must be roasted slowly with low heat and persistently stirred to prevent burning. After roasting, they are hulled, simmered over a wood fire until they get soft, then soaked in ceramic jars until they float. Meanwhile, the glutinous rice is thoroughly rinsed, steamed until it becomes tender, and left to ferment. Once the fermented rice becomes slightly yellow, it is combined with the soybeans and fermented soybean water in sealed jars. The sauce ferments for 15 to 25 days to be attractively aromatic, depending on the weather. Intense summertime temperature is ideal for speeding up fermentation. The sauce is stored in ceramic jars covered with cloth to prevent contamination and left under the summer sun for several months until fully matured. Then, the sauce is put into ceramic containers for distribution.

Although modern equipment is available, every step in Cu Da soy sauce production remains entirely manual and free from additives. The dedication to traditional methods and the distinctive taste enabled Cu Da soy sauce to earn the 3-star OCOP certification and nationwide recognition.

OCOP is a vital program aimed at stimulating important rural economic development by boosting local strengths and increasing product value; a task and solution to carrying out the National Target Program on New Rural Development. This effort has helped restructure agriculture, restructure the economy and improve incomes and living standards for local people. According to Vice Chairman of Thanh Oai District People's Committee Nguyen Trong Khien, the OCOP Program shows the strong support of the government for rural production and business activities of people, especially those in the countryside. This program encourages local producers to recognize the potential and strength of their products, adopt sustainable and safe production standards, and improve product quality, value and designs.

“In their development efforts, Cu Da villagers have improved production processes to make sure that their soy sauce meets the increasingly demanding market requirements today and competes with larger brands. Besides, Thanh Oai is focusing on developing the city’s official OCOP sales points in the district to introduce certified products, assess product quality and ensure product quality. These efforts include strengthening production-consumption cooperation and enlarging the presence of local products inside and outside the district,” he stressed.

By Ngoc Dan, Vietnam Business Forum