There's soy sauce ... And then there's real soy sauce.
Tsang Heh Kwan, 74, makes real soy sauce, the dark, viscous kind the great Chinese chefs used thousands of years ago, known as "black gold" when Dutch merchants brought it to the kitchens of Sun King Louis XIV in late 17th century Versailles.
In a small factory in Hong Kong's rural outskirts, she is one of the last people preparing the sauce to the ancient formula. When she dies, she says, perhaps it will die with her. She is unwilling to see it simply commercialized without respect.
A biochemist from China, Tsang learnt the secret art from one of the last soy sauce masters in the 1950s, before Mao Zedong's (
"When I die, this will get lost," she said at her company factory, I-Ho-Yuan Food Product Ltd. "There is nobody interested enough in soy sauce with the necessary scientific knowledge."
Her thick sweetish sauce is known to bring out the best tastes from food, particularly when used for boiling meat. It has been served at banquets for Chinese Communist leaders and found favor among gourmets in places as far away as Japan, and France.
The best soy sauce is used in moderation. It has similar culinary pedigrees to such ancient condiments as the famed fish sauce of the Roman Mediterranean world, the detailed recipes for which were lost.
Outside her office, the ground is lined with round ceramic jugs and square concrete boxes in which soybeans, the base ingredient, ferment for up to a year and more.
Tsang says the secret lies in the fine chemical balance of the fermentation and in spotting selected beans with the right micro-organisms in a room where humidity and temperature are under strict control.
Dipping her fingers to test the sticky mixture of soybeans, salt and wheat, the tall old woman said: "I am good at technology, though I am not strong in business development."
With the help of two assistants, Tsang produces about 20 tonnes of sauce each month. After fermentation, it is cooked on a slow wood fire before being funnelled manually into bottles.
Historians believe the Chinese invented soy sauce some 2,500 years ago, making the liquid seasoning from the salty paste of fermented grain. It was developed by Buddhists, who were vegetarians and shunned meat-based sauces.
But Tsang said that during the Cultural Revolution, China lost most of the recipes which soy masters had passed down through the generations. Some recipes were recovered afterwards from Japan, which had taken them from China in the 13th century, but they had been modified to suit Japanese tastes.
Even the best Japanese soy sauce is not as thick, being more suited to raw fish than meats.
Born the fourth of seven children to a chemistry professor, Tsang studied biology, chemistry and physiology in Xiamen, a coastal city in the southern province of Fujian.
In the 1950s, she joined Amoy Corp in Hong Kong, a food giant specializing in Chinese products.
She said she acquired the soy formula from Yung Da San, the soy master at Amoy whom the company had brought from Xiamen.
As a young woman, she became friends with Yung, a proud man in his 80s who turned away other high-paid scientists or apprentices.
"He let me stay with him and watch him making the sauce because I respected him, treated him with good tea and listened to his stories," she said. "I treated him with my true heart."



